WO2018148721A1

WO2018148721A1 - Highly selective akr1c3 inhibitors and methods of use thereof

Info

Publication number: WO2018148721A1
Application number: PCT/US2018/017986
Authority: WO
Inventors: Paul TRIPPIER; Kshitij VERMA; Trevor M. PENNING; Tianzhu Zhang
Original assignee: Texas Tech University System; The Trustees Of The University Of Pennsylvania
Priority date: 2017-02-13
Filing date: 2018-02-13
Publication date: 2018-08-16

Abstract

The present invention includes methods and compositions that inhibit AKR1C3 enzymatic activity and consequently reduces androgen receptor (AR) transactivation, AR and prostate specific antigen (PSA) expression levels in, for example, prostate cancer, castration-resistant prostate cancer, breast cancer, acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (T-ALL), or a leukemia.

Description

HIGHLY SELECTIVE AKR1C3 INHIBITORS AND METHODS OF USE THEREOF

TECHNICAL FIELD OF THE INVENTION

The present invention relates generally to methods and compositions used for inhibiting the biological activity of an aldo-keto reductase family 1, member C3 (AKR1C3) polypeptide.

BACKGROUND OF THE INVENTION

Without limiting the scope of the invention, its background is described in connection with compositions and methods of using the same as Aldo-keto reductase 1C3 (AKR1C3) specific inhibitors to modulate cellular or tissue proliferation, e.g., prostate cancer and/or castrate-resistant prostate cancer. Prostate cancer is the second most common cancer in men, and twenty -percent of all cases develop into castrate- resistant prostate cancer, which often presents with metastatic bone disease and is always fatal. These tumors are synthesized androgens, independently of the testes and there exists a great need in the art for such treatments. All prior AKR1C3 inhibitors have had poor selectivity between AKR1C isozymes resulting in undesirable side effects. As a result no AKR1C3 inhibitor has reached clinical trial, in part, due to lack of selectivity.

U.S. Patent Application Publication No. 2014/0371261, entitled, "Indomethacin analogs for the treatment of castrate-resistant prostate cancer," discloses compositions for inhibiting a biological activity of an aldo-keto reductase family 1, member C3 (AKR1C3) polypeptide. The compositions are indomethacin (2-[l-(4-chlorobenzoyl)-5-methoxy-2-methylindol-3-yl]acetic acid) derivatives that are AKR1 C3- specific inhibitors. Although the compositions showed a selective interaction with AKR1C3, they also interacted with AKR1C1 and AKR1C2. AKR1C1 and AKR1C2 are involved in hormonal levels and balance and blocking of these affects those levels.

SUMMARY OF THE INVENTION

Aldo-keto reductase 1C3, also known as type 5 17 β-hydroxy steroid dehydrogenase, is responsible for intratumoral androgen biosynthesis and contributes to the development of castration resistant prostate cancer (CRPC) phenotype and an eventual therapeutic failure. Significant upregulation of AKR1C3 is observed in CRPC patient samples and derived cell lines. Being a downstream catalytic enzyme for the synthesis of testosterone and 5-dihydrotestosterone (DHT), AKR1C3 represents a potential therapeutic target to manage CRPC and combat the emergence of resistance to clinically employed first line therapeutics. The present invention provides novel, potent, isoform selective and hydrolytically stable small-molecule AKR1C3 inhibitor compounds that reduces prostate cancer cell growth in vitro and sensitizes CRPC cell lines towards enzalutamide cytotoxicity. The present invention demonstrates that treatment with these inhibitors selectively induce cytotoxicity in a wide variety of cancer cells. Moreover, these inhibitors cause inhibition of AKR1C3 enzymatic activity and consequently reduces androgen receptor (AR) transactivation, AR and prostate specific antigen (PSA) expression levels in CRPC cell lines. Combination studies of the inhibitors with enzalutamide and other chemotherapies reveal a synergistic drug interaction that induces cytotoxicity of cancer cells via apoptosis. Taken together, the results demonstrate a novel therapeutic strategy for the treatment of, e.g., prostate cancer, castration-resistant prostate cancer, breast cancer, acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (T-ALL), or a leukemia. In the case of a castration-resistant prostate cancer disease phenotype, it invariably develops in prostate cancer patients following initial treatment with AR antagonists such as enzalutamide.

In one embodiment, the present invention includes an aldo-keto reductase family 1, member C3 (AKR1C3) inhibitor having one of the following structures:

derivatives thereof. In one aspect, the inhibitor is Class I or IA and

, wherein Rl is:

In another aspect, the inhibitor is

In another aspect, the inhibitor is:

In another aspect, the inhibitor is

; or , wherein R2 is:

In another aspect, the inhibitor is:

wherein R is:

In another aspect, the inhibitor is:

, wherein R3 is ; or

, wherein Rl is

, and wherein R2 is:

In another aspect, the inhibitor is:

, w ere n Rl s:

In another aspect, the inhibitor is formulated into a therapeutic effective amount sufficient to reduce or eliminate cancer cells. In another aspect, the inhibitor further comprises a chemotherapeutic agent, wherein the inhibitor and the chemotherapeutic have a synergistic effect against cancer cells. In another aspect, the inhibitor further comprises providing the inhibitor in an amount that is therapeutically effective to inhibit or reduce cellular or tissue proliferation selected from prostate cancer, castration- resistant prostate cancer, breast cancer, acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (T-ALL), or a leukemia.

In another embodiment, the present invention includes a method of modulating cellular or tissue proliferation comprising the steps of providing a therapeutic effective amount of an inhibitor that is selective for the enzyme AKR1C3 over its isoforms wherein the compound has the formula:

derivatives thereof.

In another aspect, the inhibitor is

In another aspect, the inhibitor is:

In another aspect, the inhibitor is: , wherein R2 is:

In another aspect, the inhibitor is:

, wherein R is:

In another aspect, the inhibitor is:

, wherein R3 is ; or

, wherein Rl is

In another aspect, the inhibitor is:

, w ere n Rl s:

In another aspect, the inhibitor is formulated into a therapeutic effective amount sufficient to reduce or eliminate cancer cells. In another aspect, the inhibitor further comprises a chemotherapeutic agent, wherein the inhibitor and the chemotherapeutic have a synergistic effect against cancer cells. In another aspect, the inhibitor further comprises providing the inhibitor in an amount that is therapeutically effective to inhibit or reduce cellular or tissue proliferation selected from prostate cancer, castration- resistant prostate cancer, breast cancer, acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (T-ALL), or a leukemia. In another aspect, the prostate cancer and/or castrate-resistant prostate cancer, breast cancer, leukemia is resistant to chemotherapeutic agents. In another aspect, the AKR1C3 inhibitor is synergistic with a chemotherapeutic. The present invention provides a composition that selectively inhibits an aldo-keto reductase family 1 enzyme family in a selective manner that selects the AKR1C3 isoform comprising a therapeutic effective amount of a compound or derivatives thereof.

The present invention provides a method of modulating cellular or tissue proliferation comprising the steps of: providing a therapeutic effective amount of an inhibitor that is selective for the enzyme AKR1C3 over its isoforms wherein the compound is one or more Class I, II, III, or IV baccharin derivatives. The cellular or tissue proliferation comprises prostate cancer and/or castrate-resistant prostate cancer, breast cancer, leukemia, ovarian cancer, endometrial cancer, or a combination thereof.

The present invention provides a method of preventing the development of chemotherapeutic resistant cancers comprising the steps of: providing a therapeutic effective amount of a compound that possess selectivity for the enzyme AKR1C3 over its isoforms wherein the compound is one or more Class I, II, III, or IV baccharin derivatives.

A method of treating, ameliorating or preventing cancer in a subject in need thereof, said method comprising administering to said subject a composition comprising a pharmaceutically acceptable carrier and a therapeutically effective amount of at least one Class I, II, III, or IV baccharin derivative.

BRIEF DESCRIPTION OF THE DRAWINGS

For a more complete understanding of the features and advantages of the present invention, reference is now made to the detailed description of the invention along with the accompanying figures and in which:

FIGS. 1A-1D show images of some embodiments of the compounds of the present invention.

FIGS. 2A-2C are tables showing prostate cancer cell viability was observed upon treatment with baccahrin.

FIGS. 3A-3F are graphs showing KV-37 induces potent cytotoxic activity in multiple CaP cell lines.

FIGS. 4A-4F show pre-treatment with KV-37 sensitizes LNCap and 22Rvl cells to ENZ cytotoxicity.

FIGS. 5A-5E are images showing KV-37 induces apoptosis in 22Rvl cells.

FIG. 6 is an image showing downstream molecular changes after KV-37 treatment in 22Rvl cells.

FIG. 7 is an image showing KV-37 treatment of 22Rvl cells downregulated AKR1C3.

FIGS. 8A-8B are images showing molecular changes following a combination treatment of KV-37 and ENZ in 22Rvl cells after 72 hour incubation.

FIG. 9 is a graph of the compound KV-60-5(l) showing no cytotoxicity to LNCaP cells cultured in charcoal stripped serum (CSS) after 72 hour exposure at 1 μΜ concentration. IC50 value of KV-60-5(l) was determined to be 100 μΜ. FIG. 10 is a graph of the compound KV-60-5(l) showing significant potentiation effect of the clinical antineoplastic enzalutamide in LNCaP cells cultured in charcoal stripped serum (CSS) after 72 hours.

FIG. 11 in an image of the modelling of KV-60-5a docked into the AKR1C3 enzyme.

FIG. 12 shows a synthetic scheme for the inhibitor.

FIG. 13 shows representative derivative compounds with a modification of phenyl (6).

FIG. 14 shows representative derivative compounds with a modification of Dihydrocinnamyloxy (6).

FIG. 15 shows representative derivative compounds with a Conversion of Ester to Amide Group (5).

FIG. 16 shows representative derivative compounds with a Positional Switch of Prenyl & Dihydrocinnamyloxy Group (15).

FIG. 17 shows representative derivative compounds with a Positional Switch of Dihydrocinnamoyloxy Group Analogs (3).

FIG. 18 shows representative derivative compounds a Switch of Amide Bond Direction-Reverse Amides (10).

FIG. 19 shows representative derivative compounds with a Modification of Carboxylate Group (2). FIGS. 20A to 20K show that KV-37 induces potent cytotoxic activity in multiple prostate cancer cell lines. (FIG. 20 A) Structure of KV-37. Percentage cell viability of 22Rvl cells cultured in (FIG. 20B) normal media (FIG. 20C) CSS media (FIG. 20D) normal media supplemented with 10 nM Δ4- androstenedione and (FIG. 20E) CSS media supplemented with 10 nM A4-androstenedione. Percentage cell viability of LNCaP cells cultured in (FIG. 20F) normal media and (FIG. 20G) CSS media (FIG. 20H). FIG. 201 shows the IC50 values of KV-37 determined in 22Rvl and LNaCP cells. Data shown as mean ± SD of at least three independent experiments, n=6. The competitive inhibition of NADPH dependent reduction of A4-androstene-3,17-dione mediated by AKR1C3 by KV-37. (A) KV-37 acts as a competitive Inhibitor in the conversion of [3H]A4-androstene-3,17-dione to testosterone. Increasing concentrations of KV-37 (0-10 μΜ) were used to inhibit the NADPH dependent conversion of fixed concentrations of [3H]A4-androstene-3,17-dione to testosterone catalyzed by recombinant AKR1C3 as measured by radiochromatography.

FIGS. 20J to 220K show that 22Rvl and LNCaPlC3 cells overexpress AKR1C3 whereas LNCaP and WPMY-1 exhibit low AKR1C3 levels. (FIG. 20J) Relative expression of AKR1C3 across prostate cancer cell lines. (FIG. 20K) Culture of 22Rvl cells in CSS media upregulates AKR1C3 expression levels. (NM, normal media; CSS, charcoal stripped serum media)

FIGS. 21A to 21C shows that KV-37 inhibits conversion of [3H]A4-androstene-3,17-dione to testosterone in LNCaP-lC3 cells. LNCaP-lC3 cells (1.5 x 106 cells per well) platted in phenol red-free RPMI, 5% CSS-FBS, 2 mM L-glutamine, 1% P/S and were with DMSO or 10 μΜ KV-37 for 30 min at 37 °C. After the preincubation, 100 nM [3H]A4-androstene-3,17-dione final concentration was added to the wells and cells were incubated for 24 h. FIG. 21A is solvent control; (FIG. 21B) contains 10 μΜ KV- 37 and (FIG. 21C) are LNCaP control cells treated with DMSO. The peak at 90 mm is androsterone and the peak at 120 mm is testosterone liberated after β-glucronidase treatment. The data reveal almost complete inhibition of AKR1C3 mediated testosterone production.

FIGS. 22A to 22C shows the metabolic instability of (FIG. 22A) Baccharin and (FIG. 22B) ester derivative KV-32 on incubation with mouse S9 fractions. (FIG. 22C) Half-life of baccharin and derivative AKR1C3 inhibitors upon incubation with human S9 liver fractions.

FIGS. 23A to 23C show that Baccharin does not exert cytotoxicity on prostate cancer cell lines. Percentage cell viability of (FIG. 23A) LNCaP, (FIG. 23B) 22Rvl and (FIG. 23C) LNCaPlC3 cells cultured in CSS media after baccharin treatment at indicated concentration and time points. Data shown as mean ± SD of at least three independent experiments, n=6.

FIGS. 24A to 24D Percentage cell viability of ENZ at indicated time points in (A) LNCaP cells cultured in indicated growth media (B) 22Rvl cells cultured in CSS media (C) 22Rvl cells cultured in CSS media supplemented with 10 nM A4-androstene-3,17-dione (D) 22Rvl cells cultured in normal media supplemented with 10 nM A4-androstene-3,17-dione. Data shown as mean ± SD of at least three independent experiments, n=6.

FIGS. 25A to 251 show that pre-treatment with KV-37 sensitizes prostate cancer cell lines to ENZ cytotoxicity. Percentage cell viability of prostate cancer cells when pre-treated with KV-37 for 24 h followed by ENZ treatment at indicated concentrations and time points in (FIG. 25A) 22Rvl cells cultured in normal media (FIG. 25B) and (FIG. 25C) 22Rvl cells cultured in CSS media (FIG. 25D) 22Rvl cells cultured in normal media supplemented with 10 nM A4-androstenedione (FIG. 25E) and (FIG. 25F) 22Rvl cells cultured in CSS media supplemented with 10 nM A4-androstenedione (FIG. 25G) LNCaP cells cultured in normal media and (FIG. 25H) LNCaP cells cultured in CSS media. (FIG. 251) Quantification of the degree of synergism. Combination index (CI) and dose reduction index (DRI) values for KV-37 and ENZ combination treatments in prostate cancer cells. CI and DRI indices generated using CompuSyn software. Data shown as mean ± SD of at least three independent experiments, n=6.

FIGS. 26A to 26H show that co-treatments of KV-37 with ENZ do not exert synergistic cytotoxic effects in LNCaP and 22Rvl cells. Percentage cell viability of prostate cancer cells after combination treatment with KV-37 and ENZ in (FIG. 26A- FIG. 26C) LNCaP cells at indicated time points cultured in indicated growth media (FIG. 26D- FIG. 26E) 22Rvl cells cultured in indicated growth media at 72 h and (FIG. 26F- FIG. 26H) 22Rvl cells at indicated time points cultured in indicated growth media supplemented with 10 nM A4-androstene-3,17-dione. Data shown as mean ± SD of at least three independent experiments, n=6. FIGS. 27A to 27D shows that AKR1C3 overexpression in LNCaP cells (LNCaPlC3) increases the cytotoxic activity of KV-37 and induces resistance to ENZ that is overcome by pre-treatment with KV- 37. Percentage cell viability of LNCaPlC3 cultured in CSS media after (FIG. 27A) KV-37 treatment at indicated time points and concentrations (table insert showing the IC50 values) (FIG. 27B) ENZ treatment at indicated time points and concentrations (FIG. 27C) co-treatment with KV-37 and ENZ for 72 h and (FIG. 27D) pre-treatment with KV-37 followed by ENZ exposure for 72 h. Table insert showing the parameters for quantifying the degree of synergism. Data shown as mean ± SD of at least three independent experiments, n=6.

FIGS. 28A to 28D show that KV-37 induces apoptosis in prostate cancer cells alone and potentiates the degree of apoptosis when combined with ENZ. (FIG. 28A) Dose and time-dependent increase in apoptotic cell population after treatment with KV-37 in indicated cell lines as analyzed by AnnexinV/PI co-staining. (FIG. 28B) Increase in apoptotic cell population after treatment with indicated concentrations of KV-37, ENZ and a 24 h pre-treatment combination of KV-37 and ENZ in indicated cell lines analyzed 72 h post ENZ exposure by AnnexinV/PI co- staining. (FIG. 28C) Western blot showing an increase in C-caspase3 and C-PARP levels after treatment with KV-37 at indicated concentration and time points in prostate cancer cells. (FIG. 28D) Western blot showing a greater increase in C-caspase3 and C-PARP levels with a 24 h pre-treatment combination of KV-37 and ENZ in prostate cancer cells analyzed 72 h post ENZ exposure. Data shown as mean ± SD of at least three independent experiments, n=3. *, p<0.05; **, pO.01; ****, pO.0001; ns, non-significant.

FIGS. 29 A to 29D show that Molecular changes following KV-37 treatment. Treatment with KV-37 alone at indicated concentration and time points in (FIG. 29 A) 22Rvl and (FIG. 29B) LNCaPlC3 cells cultured in CSS media. Treatment with indicated concentrations of KV-37, ENZ and a 24 h pre-treatment combination of KV-37 and ENZ in (FIG. 29C) 22Rvl cells and (FIG. 29D) LNCaPlC3 cells cultured in CSS media analyzed 72 h-post ENZ exposure.

FIGS. 30A to 30E show that KV-37 induces tumor growth inhibition in prostate cancer xenografts. Reduction in (FIG. 30A) prostate tumor volume and (FIG. 30B) prostate tumor weight in 22Rvl murine xenografts after treatment with 20 mg/Kg KV-37. (FIG. 30C) Representative images showing a reduction in tumor size after treatment with 20 mg/Kg KV-37. FIG. 30D shows the mice body weight versus days post implantation. FIG. 30E shows the pharmacokinetic parameters determined in plasma after treatment with 20 mg/Kg KV-37.

FIGS. 31A to 3 ID Indomethacin exerts a weak synergistic drug effect in LNCaPlC3 cells and KV-37 does not induce cytotoxicity alone or in combination with ENZ in WPMY-1 cells. Percentage cell viability of LNCaPlC3 cells after (FIG. 31 A) treatment with indicated concentrations of indomethacin for 96 h and (FIG. 3 IB) 24 h pre-treatment with indomethacin followed by ENZ treatment for 72 h. Percentage cell viability of WPMY-1 cells after (FIG. 31C) treatment with indicated concentrations of KV-37 for 96 h and (FIG. 3 ID) 24 h pre-treatment with KV-37 followed by ENZ treatment for 72 h. Table insert showing the quantification of the degree of synergism. Data shown as mean ± SD of at least three independent experiments, n=6.

FIG. 32 shows the SAR strategy map for the design of Baccharin derivatives.

FIGS. 33A to 33D show co-treatment of AKR1C3 inhibitors with daunorubicin in HL-60 cells. Percentage cell viability after 72 h co-treatment of daunorubicin with (33A) 1 (33B) 26a (33C) 49a (33D) 49g at indicated concentrations.

FIGS. 34A to 34D show Co-treatment of AKR1C3 inhibitors with daunorubicin in KGla cells. Percentage cell viability after 72 h co-treatment of daunorubicin with (34A) 1 (34B) 26a (34C) 49a (34D) 49g at indicated concentrations.

FIGS. 35A to 35D show Co-treatment of AKR1C3 inhibitors with daunorubicin in THP-1 cells. Percentage cell viability after 72 h co-treatment of daunorubicin with (35A) 1 (35B) 26a (35C) 49a (35D) 49g at indicated concentrations.

FIGS. 36A to 36D show 24 h Pre-treatment of AKR1C3 inhibitors with daunorubicin in HL-60 cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of (36A) 1 (36B) 26a (36C) 49a (36D) 49g at indicated concentrations.

FIGS. 37A to 37D show 24 h Pre-treatment of AKR1C3 inhibitors with daunorubicin in KGla cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of (37 A) 1 (37B) 26a (37C) 49a (37D) 49g at indicated concentrations.

FIGS. 38A to 38D show 24 h Pre-treatment of AKR1C3 inhibitors with daunorubicin in THP-1 cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of (38A) 1 (38B) 26a (38C) 49a (38D) 49g at indicated concentrations.

FIGS. 38E to 38F show Treatment of AML cells with chemotherapeutics. Percentage cell viability after 72 h treatment of AML cells with (38E) daunorubicin and (38F) AraC at indicated concentrations.

FIGS. 39A to 39D show that co-treatment of AKR1C3 inhibitors with AraC in HL-60 cells. Percentage cell viability after 72 h co-treatment of AraC with (39A) 1 (39B) 26a (39C) 49a (39D) 49g at indicated concentrations.

FIGS. 40A to 40D show that co-treatment of AKR1C3 inhibitors with AraC in KGla cells. Percentage cell viability after 72 h co-treatment of AraC with (40A) 1 (40B) 4 (40C) 6 (40D) 7 at indicated concentrations.

FIGS. 41A to 41D show that co-treatment of AKR1C3 inhibitors with AraC in THP-1 cells. Percentage cell viability after 72 h co-treatment of AraC with (41 A) 1 (4 IB) 4 (41C) 6 (4 ID) 7 at indicated concentrations. FIGS. 42A to 42D show the effect of 24 h Pre-treatment of AKR1C3 inhibitors with AraC in HL-60 cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of (42A) 1 (42B) 26a (42C) 49a (42D) 49g at indicated concentrations.

FIGS. 43 A to 43D show the effect of 24 h Pre-treatment of AKR1C3 inhibitors with AraC in KGla cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of (43A) 1 (43B) 26a (43C) 49a (43D) 49g at indicated concentrations.

FIGS. 44A to 44D show the effect of 24 h Pre-treatment of AKR1C3 inhibitors with AraC in THP-1 cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of (44A) 1 (44B) 26a (44C) 49a (44D) 49g at indicated concentrations.

FIGS. 45A to 45D show the synergistic effect of compound 49a with daunorubicin in primary T-ALL cells. Percentage cell viability after 72 h co-treatment of 49a and daunorubicin in (45 A) COG-317 (45B) COG-329 cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of 49a in (45C) COG-317 (45D) COG-329 cells.

FIGS. 45E to 45G shows treatment of COG T-ALL cells with 49a and chemotherapeutics. Percentage cell viability after 72 h treatment of AML cells with (45E) 49a (45 G) daunorubicin and (45H) AraC at indicated concentration and time points.

FIGS. 46A to 46D show the synergistic effect of compound 49a with AraC in primary T-ALL cells. Percentage cell viability after 72 h co-treatment of 49a and AraC in (46 A) COG-317 (46B) COG-329 cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of 49a in (46C) COG- 317 (46D) COG-329 cells.

FIGS. 46E and 46F Combination treatment of BMMNC cells with 49a and chemotherapeutics. Percentage cell viability of BMMNC cells after pre-treatment with 49a followed by 72 h incubation with (46E) AraC and (46F) daunorubicin at indicated concentrations.

FIG. 47 shows a Baccharin SAR map

FIGS. 48A to 48D show the treatment of HL-60 cells with AKR1C3 inhibitors. Percentage cell viability after 72 h treatment of HL-60 cells with (48A) 1 (48B) 26a (48C) 49a (48D) 49g at indicated concentrations and time points.

FIGS. 49A to 49D show the treatment of KGla cells with AKR1C3 inhibitors. Percentage cell viability after 72 h treatment of KGla cells with (49 A) 1 (49B) 26a (49C) 49a (49D) 49g at indicated concentrations and time points.

FIGS. 50A to 50D shows the treatment of THP-1 cells with AKR1C3 inhibitors. Percentage cell viability after 72 h treatment of THP-1 cells with (50A) 1 (50B) 26a (50C) 49a (50D) 49g at indicated concentrations and time points. DETAILED DESCRIPTION OF THE INVENTION

While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.

To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as "a", "an" and "the" are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the invention, except as outlined in the claims.

As used herein, the term AKR1C3 is an acronym for aldo-keto reductase family 1, member C3 polypeptide, Aldo-keto reductase 1C3, and is also referred to as type 5 17 -hydroxysteroid dehydrogenase.

Prostate cancer is the second leading cause of mortality among American men with the highest incidence rate of all cancers reported in the United States. Surgical removal of prostate by radical prostatectomy and radiation therapy are applied to resect localized tumor. However, the treatment of advanced and metastatic forms of prostate cancer relies heavily on androgen deprivation therapy (ADT) that involves surgical (orchiectomy) and/or chemical castration. Chemical agents such as GnRH agonists (Lupreolide, goserelin, buserelin) and antiandrogens (bicalutamide, enzalutamide) reduce the levels of circulating androgens that consequently retard prostate cancer cell proliferation. After an initial response to ADT via castration, invariably in all prostate cancer patients the tumor adapts, giving rise to a more aggressive and fatal phenotype known as Castration Resistant Prostate Cancer (CRPC). CRPC is marked by molecular changes that involve an increase in the expression of androgen synthesizing enzymes, androgen receptor mutation and/or its reactivation. Such adaptations can lead to an increase in intratumoral androgen biosynthesis along with an increase in tumor responsiveness to circulating castrate levels of androgens.

Based on the prior art, it is well known that AKR1C3 plays a role in cancer development and chemotherapy resistance, and that this enzyme is a target for treating castrate resistant prostate cancer. Although inhibitors are available that can block AKRlC3's enzymatic activity, they also block AKR1C1 and AKRlC2's activities, which affects healthy hormonal levels and balance.

The aldo-keto reductase family 1-member C (AKR1C) enzymes are oxidoreductases that catalyze NADPH-dependent reductions of aldehydes and ketones in a range of steroids, carbohydrates, and prostaglandins. The isoform AKR1C3 specifically catalyzes the conversion of androgen precursors to potent androgen receptor (AR) ligands, testosterone and a-dihydrotestosterone. AKR1C3 is also known as prostaglandin F synthase and as it catalyzes the conversion of prostaglandin D2 to 11 ^-prostaglandin F2^a and its prostanoids, which affects the growth and spread of myeloblasts and myelocytes, it is therefore an important regulator of myeloid cell proliferation and differentiation.

The dual capabilities of AKR1C3 make it responsible for both the pathogenesis and progression of hormone dependent and independent cancers, including castration resistant prostate cancer (CRPC) and acute myeloid leukemia (AML). Additionally, AKR1C3 can lead to clinical chemotherapeutic resistance, as it reduces the effectiveness of first line of defense drugs for CRPC and AML.

Previous AKR1C3 inhibition research has found compounds with some degree of selectivity, but further improvements can be made to reduce the inhibition of the other AKR1C isoforms. The strategy behind these mechanisms has been taking known AKR1C3 inhibitors, and altering their functional groups through meta and para-directing to increase the inhibitor's level of selectivity. Due to the lack of high selectivity in previous research, no AKR1C3 inhibitor has been approved for clinical testing.

The present invention provides a series of compounds that possess the greatest selectivity for the enzyme AKR1C3 over its isoforms ever reported. The AKR1C3 enzyme is a therapeutic target for prostate and breast cancer and leukemia.

Abiraterone acetate (AA) acts by inhibiting CYP17A1, an upstream enzyme in the steroid biosynthetic pathway, which was approved by the FDA for CRPC treatment in 2011 and is effective in treating state 2 of CRPC. However, a majority of patients experience hypertensive crisis due to accumulation of desoxycorticosterone (DOC) and hence, co-administration with prednisone is imperative. Enzalutamide (ENZ) is another clinically used therapeutic that exerts potent androgen receptor (AR) antagonistic activity by inhibiting AR nuclear translocation, co-activator recruitment and AR binding to androgen response elements (ARE's) and henceforth, it could be effective up to state 3 CRPC. Albeit initial response, resistance to both AA and ENZ still develops by either an increase in intratumoral CYP17A1 expression or AR overexpression along with AR mutation that impairs inhibitor binding. Furthermore, due to the tumor heterogeneity and complex dynamics of androgen biosynthesis via various compensating pathways along with frequent mutations in AR and androgen biosynthetic enzymes the prognosis for patients that have advanced to CRPC still remains bleak. A need for novel therapeutics that can delay or reverse the emergence of resistance is inevitable.

Aldo-keto reductase 1C3 (AKR1C3) is a downstream enzyme in the steroid biosynthetic pathway and plays a pivotal role in the pathogenesis and progression of CRPC by catalyzing the conversion of weak androgen precursors to the potent androgen receptor (AR) ligands: testosterone (T) and 5a- dihydrotestosterone (5a-DHT). Also known as prostaglandin (PG) F synthase, AKR1C3 catalyzes the conversion of PGD2 to l ip-PGF2a and PGF2a prostanoids and hence acts as an important regulator of myeloid cell proliferation and differentiation. This dual enzymatic action makes AKR1C3 responsible for the pathogenesis and progression of both hormone dependent and independent cancers. A considerable interest has been developed in investigating the role of AKR1C3 in a variety of cancers of the breast, lungs and colon. Prior studies have already validated the role of AKR1C3 in the pathogenesis and progression of prostate cancer. Clinically, AKR1C3 has been shown to be the most upregulated enzyme isoform among CRPC patients. Apart from inducing a CRPC phenotype, AKR1C3 is also responsible to mediate resistance to ENZ by providing a source of intratumoral androgens. As the enzyme acts at the final steps of androgen synthesis pathway, it eliminates the risk of DOC accumulation and eventually development of life threatening hypertension. Such activities make AKR1C3 an attractive target for managing CRPC disease progression as well as therapeutic resistance. Related isoforms AKR1C1 and AKR1C2 share high homology with AKR1C3 and are responsible for normal steroid metabolism. Hence, design of a potent yet isoform selective AKR1C3 inhibitor is a major challenge in the drug discovery process.

EXAMPLE 1. Novel compounds with higher selectivity for the enzyme AKR1C3 using a structure- activity relationship (SAR) optimization approach.

The present invention provides a series of compounds that possess the greatest selectivity for the enzyme AKR1C3 over its isoforms ever reported by adopting a structure-activity relationship (SAR) optimization approach based on a structurally novel natural product scaffold 'baccharin' isolated from Brazilian green propolis exhibiting potent AKR1C3 inhibition activity (IC50 = 100 nM) and crucially, exquisite selectivity for the AKR1C3 isoform. Because of the metabolic instability of the ester side chain hydrolytically stable analogues were synthesized that displayed superior AKR1C3 inhibitory activity than baccharin with retention of isoform selectivity. In our previous studies the inventors have shown that derivative AKR1C3 inhibitors display a very potent synergistic effect in combination with clinical chemotherapeutic agents in a panel of leukemia cell lines. In this report, the inventors demonstrate the activity of a hydrolytically stable amide analogue of baccharin to exert a cytotoxic effect in a panel of prostate cancer cell lines and a very high degree of synergistic drug interaction with ENZ. Mechanistic studies demonstrate apoptotic cell death in sensitive and ENZ resistant prostate cancer cell lines with a consequent reduction in AR and PSA levels.

FIGS. 1A-1D show examples of AKR1C3 inhibitors synthesized based on baccharin structural scaffold. KV-37 was chosen for further studies as it demonstrated a very potent AKR1C3 inhibitory IC50 of 66 nM. Androgen dependent 22Rvl and LNCaP cell lines were chosen to evaluate the activity of KV-37. 22Rvl cells were found to be high expressors of AKR1C3 as compared to LNCaP. Moreover, 22Rvl cell line, being intrinsically resistant to ENZ was an apt model for conducting CRPC studies.

Human liver stability of Baccharin and derivative AKR1C3 inhibitors: Baccharin and derivative AKR1C3 inhibitors were subjected to incubation with human S9 fractions in the presence of phase I co- factors from 0-240 minutes. Aliquots were withdrawn and analyzed by LC-MS method at various time points. The half-life of the inhibitor compounds is summarized in table 1. Table 1

As expected, baccharin and the ester analogue were readily hydrolyzed. The amide inhibitor KV-37 displayed a remarkable stability and half-life of >240 min. The AKR1C3 inhibitory activity of baccharin was completely abrogated when, upon hydrolysis it yielded the known phenol drupanin, exhibiting AKR1C3 inhibition at IC50 of 15 μΜ and 7 fold selectivity over AKR1C2.

FIGS. 2A-2C are tables showing prostate cancer cell viability observed upon treatment with baccahrin. No reduction in prostate cancer cell viability was observed upon treatment with baccahrin. (FIG. 2A, 2B, 2C) very low levels of cytotoxicity were observed in DU-145, LNCaP and VCaP cells cultured in normal media when treated with baccharin at concentrations up to 100 μΜ. Effect of AKR1C3 inhibitors on CaP cell viability: Baccharin and derivative AKR1C3 inhibitors were screened for cytotoxic effects in a panel of prostate cancer cell lines (DU-145, LNCaP, 22Rvl, VCaP). Baccharin consistently displayed a lack of toxicity among all the cell lines tested up to concentrations as high as 100 μΜ (FIG. 2A, 2B, 2C). This is in agreement with previous studies demonstrating little or no toxicity for baccharin in various cancer cell lines, as assayed in the NCI-60 panel. KV-37 however, demonstrated a potent cytotoxic effect, which was time dependent in androgen dependent LNCaP, VCaP and 22Rvl cell lines.

FIGS. 3A-3F are graphs showing KV-37 induces potent cytotoxic activity in multiple CaP cell lines. Dose and time dependent reduction in cell viability after inhibitor treatment: (FIGS. 3A and 3B) LNCaP cells cultured in normal media and CSS media respectively. (FIG. 3C) VCaP cells cultured in normal media. (FIGS. 3D, 3E, 3F) 22Rvl cells cultured in normal media, CSS media and CSS media supplemented with 10 nM AD respectively. A further enhancement in cytotoxic activity was observed when the cells were cultured in charcoal stripped serum (CSS) media. The IC50 of KV-37 decreased from 45 μΜ to 25 μΜ in LNCaP cells and from 50 μΜ to 25 μΜ in 22Rvl cells upon incubation in CSS media as against hormone replete media. In the next set of experiments KV-37 was incubated with 22Rvl cells in CSS media supplemented with 10 nM A4-androstenedione (AD). Similar dose and time dependent reduction in cell viability was observed: IC50 being 25 μΜ at 72 hours. At higher inhibitor concentrations of 75 μΜ complete abrogation of cell viability was observed in LNCaP and 22Rvl cells when cultured in CSS media.

An increase in cytotoxic activity of KV-37 among CaP cells cultured in CSS media is attributable to the overexpression of AKR1C3 when cells are grown in media devoid of androgens. This drives the cellular phenotype to more closely resemble clinical castrate conditions where the cancer cells are dependent on AKR1C3 for survival and proliferation. A4-AD is a weak AR ligand and a substrate for AKR1C3. The enzyme converts A4-AD to more potent AR ligand testosterone that drives cell proliferation. The addition of 10 nM A4-AD to CSS culture further mimics the clinical CRPC phenotype when only castrate levels of circulating androgens are available.

Compound KV-37 sensitizes CaP cells to enzalutamide cytotoxicity and exerts a synergistic drug effect: The dose response curve of ENZ in LNCaP and 22Rvl cells displays an increase in resistance upon culture in CSS media. In order to restore the sensitivity of these cell lines to ENZ cytotoxicity, LNCaP and 22Rvl cells were pre-treated with KV-37 for 24 hours followed by exposure to ENZ. The combination demonstrated a remarkable synergistic effect at both the time points of 48 and 72 hours post ENZ exposure in normal as well as CSS media. Among CSS cultures, concentrations as low as 1 μΜ of KV-37 were capable of sensitizing both 22Rvl and LNCaP cell lines to reduce cell viability by 50% upon treatment with only 1 μΜ ENZ when either agent alone did not exert any toxic behavior.

FIGS. 4A-4F show pre-treatment with KV-37 sensitizes LNCap and 22Rvl cells to ENZ cytotoxicity. (FIG. 4A, 4B) 24 hour pre-treatment of LNCaP cells in normal and CSS media followed by treatment with various concentrations of ENZ for 72 hours (FIG. 4C, 4D, 4E) 24 hour pre-treatment of 22Rvl cells in normal and CSS media followed by treatment with various concentrations of ENZ at indicated time points. (FIG. 4F) Quantification of the degree of synergism. Combination and dose reduction indices (CI, DRI) generated using compusyn software. However, co-treatment experiments did not show any adjuvant effect between both cell lines. Quantification of degree of synergism was made using the Chou- Talalay method. Up to a 100-fold reduction in ENZ dosing was achieved in 22Rvl cells while in LNCaP cells 40 fold reduction was observed.

FIGS. 5A-5D are images showing KV-37 induces apoptosis in 22Rvl cells. (FIG. 5A, 5B) Dose dependent Increase in apoptotic cell population in 22Rvl cells at indicated time points. (FIG. 5C) Graph quantifying the percentage of apoptotic cells after KV-37 treatment. (FIG. 5E) Western blots showing a dose dependent increase in c-caspase and C-PARP after treatment with KV-37 at indicated time points in CSS media. KV-37 induces cell death in 22Rvl cells via apoptosis: 22Rvl cells cultured in CSS media were treated with increasing doses KV-37 for 48 and 72 hours and stained with AnnexinV/PI to measure the apoptotic cell percentage following treatment. FIG. 5 outlines the increase in the percentage of apoptotic cells with increase in concentration of KV-37 as analyzed by flow cytometry. Compound incubation for 72 hours (FIG. 5B) demonstrates a further increase in apoptotic cell percentage as compared to the 48 hour time point (FIG. 5A). FIGS. 5C and 5D outline the percent increase in apoptosis as compared to the control. In order to further corroborate these findings, western blot analysis was conducted after inhibitor treatment following a similar dosing schedule. The results, in agreement with flow cytometry data consistently show a dose dependent increase in the levels of c-caspase and c- PARP with an even higher expression at 72 hours as compared to 48 hours incubation time (FIGS. 5E and 5F). Taken together, the data strongly suggests apoptosis as the primary mechanism of cytotoxicity for compound KV-37. FIG. 6 is an image showing downstream molecular changes after KV-37 treatment in 22Rvl cells. Western blot showing a decline in AKR1C3, AR and PSA levels. Treatment of 22Rvl cells with KV-37 downregulates AKR1C3, AR and PSA expression: To evaluate molecular changes following inhibitor treatment in 22Rvl cells, western blot analysis was conducted to measure the expression levels of AKR1C3, AR and PSA. As expected, AKR1C3 expression levels decline after treatment with KV-37 and the downregulation is even stronger at a longer incubation time of 72 hours (FIG. 6). Since, a functional correlation exists between AKR1C3 and AR, it was prudent to measure AR levels after treatment. The inventors observed that the decline in AR levels complement AKR1C3 downregulation and could be the reason for sensitizing the cells to ENZ cytotoxicity to exert a synergistic drug interaction. PSA is widely used as a biomarker for prostate cancer and governs the disease progression. The inventors probed PSA levels after inhibitor treatment that shows a dose dependent reduction in PSA expression signifying a beneficial therapeutic outcome. To further confirm a reduction in the expression of AKR1C3, 22Rvl cells were treated with KV-37 at 1 and 10 μΜ concentration for 48 hours followed by immunostaining against AKR1C3.

FIG. 7 is an image showing KV-37 treatment of 22Rvl cells downregulated AKR1C3. Immunocytochemical analysis showing a concentration dependent decline in AKR1C3 levels after 48 hours incubation. The data clearly indicates a reduction in AKR1C3 levels as denoted by the green stain. Counterstaining with DAPI shows no morphological changes in the nucleus. Combination of KV-37 with ENZ synergistically downregulates AKR1C3, AR and PSA expression and upregulates c-caspase and c-PARP levels:

FIGS. 8A-8B are images showing molecular changes following a combination treatment of KV-37 and ENZ in 22Rvl cells after 72 hours incubation. To determine the mechanism of synergistic interaction between KV-37 and ENZ, western blot analysis was carried out to measure molecular changes in the combination treatments. As outlined in FIG. 8A, the combination of 25 μΜ KV-37 with 25 μΜ ENZ completely abrogates PSA expression with a concomitant decrease in AKR1C3 and AR levels at 72 hours (FIG. 8B). A predominant increase in c-caspase and c-PARP levels was also observed at both time points. Taken together the data indicate apoptotic cell death as a primary mechanism of synergistic cytotoxic effect as a consequence of reduction in the activity of AKR1C3 and AR.

The disclosed compositions are AKR1C3 inhibitors with >1800-fold selectivity for AKR1C3 over its other isoforms. It provides a composition for the treatment of cancer and contributes to the effectiveness of chemotherapeutic drugs that are otherwise reduced in effect by AKR1C3.

The aldo-keto reductase family 1 member C (AKR1C) enzymes are oxidoreductases, which catalyze the NADPH-dependent reduction of aldehyde and ketone functionalities on a range of steroids, carbohydrates, and prostaglandins. The AKR1C3 enzyme isoform catalyzes the downstream conversion of androgen precursors to the potent androgen receptor (AR) ligands: testosterone and 5a- dihydrotestosterone (5a-DHT). Also known as prostaglandin (PG) F synthase, AKR1C3 catalyzes the conversion of PGD2 to l ip-PGF2a and PGF2a prostanoids and hence acts as an important regulator of myeloid cell proliferation and differentiation. This dual enzymatic action makes AKR1C3 responsible for the pathogenesis and progression of both hormone dependent and independent cancers such as Castration Resistant Prostate Cancer (CRPC) and Acute Myeloid Leukemia (AML). AKR1C3 is not only responsible for the pathogenesis of the aforementioned malignancies but also mediates resistance to clinical chemotherapeutics. It reduces the effectiveness of enzalutamide (first line therapy for CRPC) by providing a source of intratumoral androgens and transforms anthracycline antibiotics (first line therapy for AML) to inactive hydroxy metabolites. Related isoform AKR1C2 share high homology with AKR1C3 and transforms potent androgen 5a-DHT to an inactive metabolite. Hence, inhibition of 1C2 isoform is undesirable and the discovery of a potent yet isoform selective AKR1C3 inhibitor is paramount to manage cancer progression and obliterate the therapeutic resistance. Based on a natural product scaffold the inventors have synthesized and characterized a novel, potent and extremely selective AKR1C3 inhibitor that exhibits >1800- fold selectivity towards the AKR1C3 isoform.

Based on a natural product scaffold we have synthesized and characterized a novel, potent and extremely selective AKR1C3 inhibitors (KV-60-5a) and derivatives, that exhibits >1800-fold selectivity towards the AKR1C3 isoform. This is the most selective AKR1C3 inhibitor that has ever been discovered.

KV-60-5a, the most selective AKR1C3 inhibitor yet identified, is shown to be non-toxic to LNCaP prostate cancer cells (when grown in charcoal stripped serum (CSS), which serves to upregulate AKR1C3 expression) at 1 μΜ concentration.

FIG. 9 is a graph of the compound KV-60-5a showing no cytotoxicity to LNCaP cells cultured in charcoal stripped serum (CSS) after 72 hours exposure at 1 μΜ concentration. IC50 value of KV-60-5a was determined to be 100 μΜ. Note that although AKR1C3 expression is enhanced in LNCaP cells grown in CSS media the relative expression of the enzyme target is still low. Clinical samples of castration resistant prostate cancer and other cell lines express much greater levels of AKR1C3. In such cell lines both direct toxicity and potentiation effect are expected to be much greater. These experiments are currently ongoing.

FIG. 10 is a graph of the compound KV-60-5a showing significant potentiation effect of the clinical antineoplastic enzalutamide in LNCaP cells cultured in charcoal stripped serum (CSS) after 72 hours. Synergistic treatment of 1 μΜ of KV-60-5a with 1 μΜ of the clinical antineoplastic enzalutamide results in 42% cell viability compared with 1 μΜ of enzalutamide alone which results in 82% cell viability (FIG. 10). A potentiation effect of approximately 100% for LNCaP cells grown in CSS.

FIG. 11 in an image of the modelling of KV-60-5a docked into the AKR1C3 enzyme. Enabled by the synthesized library of AKR1C3 inhibitors the inventors have conducted quantitative structure -activity relationship (QSAR) computer modelling that has identified compounds with retained selectivity and predicted picomolar affinity. Modelling predictions show that the structure of the highly selective inhibitor KV-60-5a changes the pose of the compound when bound with AKR1C3. This results in pi-pi stacking interactions between aromatic amino acids TYR216, TRP227 and PHE311, and aromatic constituents of the inhibitors, which accounts for the enhanced affinity.

FIG. 12 shows a synthetic scheme for the inhibitor. As seen in 1, 3-bromo-5-iodo-N-(2- phenylethyl)benzamide (2): To a solution of 3-bromo-5-iodo benzoic acid (500 mg, 1.5 mmol) in dry toluene (10 mL) was added SOC12 (290 μΕ, 4 mmol) and the mixture was refluxed overnight. The reaction vessel was cooled to room temperature and the solvent was evaporated in vacuo. The resultant brown oil was used further without purification. To a solution of 3-bromo-5-iodo benzoyl chloride in DCM (10 mL) was added DMAP (26 mg, 0.2 mmol) and the flask was purged with nitrogen. 2- phenylethylamine (250 μΕ, 2 mmol) and NEt3 (420 μΕ, 3 mmol) were added to the flask and the mixture was stirred at 70° C overnight. The reaction mixture was cooled to room temperature, diluted with DCM, washed with a saturated aqueous NaHC03, water and extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4: 1) provided the title compound as a white solid ( 645 mg, 1.5 mmol, 98%). tert-butyl (2E)-3-{3-bromo-5-[(2- phenylethyl)carbamoyl]phenyl}prop-2-enoate (3): To a solution of (2) (645 mg, 1.5 mmol) in dry toluene (15 mL), was added PPh3 (40 mg, 0.15 mmol), Pd(OAc)2 (17 mg, 0.07 mmol) and the flask was purged with nitrogen. tert-Butylacrylate (300 μΐ., 2.0 mmol) and NEt3 (560 μΐ., 4.0 mmol) were added and the mixture was stirred at reflux overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried ( a2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a brown oil (288 mg, 0.67 mmol, 45%). tert-butyl (2E)-3-[3-(3-methylbut-2-en-l-yl)-5-[(2- phenylethyl)carbamoyl]phenyl] prop-2-enoate (4): To a solution of (3) (80 mg, 0.18 mmol) in dry DMF (2 mL) was added Cs2C03 (130 mg, 0.4 mmol), Pd(dppf)C12 (8.5 mg, 0.01 mmol) and the flask was purged with nitrogen. Prenyl boronic acid pinacol ester (70 μΐ., 0.3 mmol) was added and the mixture was stirred at 90° C overnight. The reaction was allowed to cool and was filtered through a CELITE® pad with EtOAc. The solvent was evaporated in vacuo, re-dissolved in DCM and the residual DMF removed by washing with copious amounts of water in DCM, dried ( a2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4: 1, 2: 1) provided the title compound as a transparent oil (50 mg, 0.12 mmol, 66%). (2E)-3-[3-(3-methylbut-2-en-l-yl)-5-[(2- phenylethyl)carbamoyl]phenyl]prop-2-enoic acid (5): To a solution of (4) (50 mg, 0.12 mmol) in dry toluene (10 mL) was added silica gel (5 mL) and the suspension was stirred at reflux overnight. The reaction was allowed to cool and the mixture was filtered after diluting with 20% MeOH in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (DCM:MeOH = 20: 1) provided the title compound as a white solid (21.7 mg, 0.06 mmol, 50%).

FIG. 13 shows representative derivative compounds with a modification of phenyl (6). FIG. 14 shows representative derivative compounds with a modification of Dihydrocinnamyloxy (6). FIG. 15 shows representative derivative compounds with a Conversion of Ester to Amide Group (5). FIG. 16 shows representative derivative compounds with a Positional Switch of Prenyl & Dihydrocinnamyloxy Group (15). FIG. 17 shows representative derivative compounds with a Positional Switch of Dihydrocinnamoyloxy Group Analogs (3). FIG. 18 shows representative derivative compounds a Switch of Amide Bond Direction-Reverse Amides (10). FIG. 19 shows representative derivative compounds with a Modification of Carboxylate Group (2).

EXAMPLE 2. A Highly Potent AKR1C3 Inhibitor Exhibits Single Agent Cytotoxicity and Significantly Potentiates Enzalutamide in Combination Therapy Across Prostate Cancer Models.

Aldo-keto reductase 1C3 (AKR1C3) also known as type 5 17 β-hydroxysteroid dehydrogenase is responsible for intratumoral androgen biosynthesis, contributing to the development of castration- resistant prostate cancer (CRPC) and eventual chemotherapeutic failure. Significant upregulation of AKR1C3 is observed in CRPC patient samples and derived CRPC cell lines. As AKR1C3 is a downstream steroidogenic enzyme synthesizing intratumoral testosterone (T) and 5a-dihydrotestosterone (DHT), the enzyme represents a promising therapeutic target to manage CRPC and combat the emergence of resistance to clinically employed androgen deprivation therapy. Herein, the inventors demonstrate the antineoplastic activity of a potent, isoform selective and hydrolytically stable AKR1C3 inhibitor (E)-3-(4-(3-methylbut-2-en-l-yl)-3-(3- phenylpropanamido)phenyl)acrylic acid (KV-37) which reduces prostate cancer cell growth in vitro and in vivo, and sensitizes CRPC cell lines (22Rvl and LNCaPlC3) towards enzalutamide cytotoxicity. Crucially, KV-37 does not induce cytotoxicity in non- malignant WPMY-1 prostate cells nor does it induce weight loss in mouse xenografts. Moreover, KV-37 reduces androgen receptor (AR) transactivation and prostate specific antigen (PSA) expression levels in CRPC cells lines indicating a therapeutic drug effect in prostate cancer. Combination studies of KV-37 with enzalutamide reveal a very high degree of synergistic drug interaction that induces significant cytotoxicity in prostate cancer cells via apoptosis, resulting in >200-fold potentiation of enzalutamide cytotoxicity in drug resistant 22Rvl cells. These results demonstrate a promising therapeutic strategy for the treatment of drug resistant CRPC that invariably develops in prostate cancer patients following initial treatment with AR antagonists such as enzalutamide.

Prostate cancer is the third (1) leading cause of mortality among American men and has the highest incidence of all cancers reported in the US (2). Surgical removal of the prostate by radical prostatectomy and radiation therapy to resect the localized tumor are standard therapeutic interventions (3). The treatment of advanced and metastatic forms of prostate cancer relies heavily on androgen deprivation therapy (ADT) that involves surgical (orchiectomy) and/or chemical castration (4). Chemical agents such as gonadotropin releasing hormone (GnRH) agonists (Lupreolide, (5) goserelin, (6) buserelin (7)) and antiandrogens (bicalutamide (8)) retard prostate cancer cell proliferation and lead to remission. After an initial response to ADT that results in castrate levels of circulating androgens, the tumor adapts, giving rise to a more aggressive and fatal disease known as castration-resistant prostate cancer (CRPC) which is characterized by molecular changes that include an increase in the expression of androgen synthesizing enzymes and reactivation of androgen signaling (9,10). Such adaptations can lead to relapse despite the presence of circulating castrate levels of androgens (11,12).

Abiraterone acetate (AA) was approved by the US Food and Drug Administration for CRPC treatment in 2011 and acts by inhibiting P450cl7 (13), an upstream enzyme in the steroid biosynthetic pathway and is effective in CRPC where tumor progression is dependent on intracrine androgen synthesis that consequently activates AR signaling (14,15). However, to prevent hypertensive crisis due to accumulation of desoxycorticosterone (DOC) in the adrenal gland, co-administration with prednisone is imperative (16). Enzalutamide (ENZ) is another clinically used therapeutic that exerts potent androgen receptor (AR) antagonistic activity by inhibiting AR nuclear translocation, co-activator recruitment and AR binding to androgen response elements (ARE's) (17). The chemotherapeutic is effective up to stage 3 CRPC where proliferation is dependent on AR activation that occurs even in the absence of an androgen ligand (15). After an initial response to AA or ENZ, resistance develops rapidly due to increase in intratumoral androgen biosynthesis (18), AR overexpression, AR mutation, that makes the receptor ligand promiscuous, or the appearance of AR splice variants that make the AR constitutively active in the absence of the ligand binding domain (15,19,20). Due to tumor heterogeneity and the emergence of adaptive pathways of androgen biosynthesis (21), combined with frequent mutations in AR and androgen biosynthetic enzymes (10,22), the prognosis for patients that have advanced to CRPC remains bleak. Thus, there is an urgent need for novel therapeutics that can delay or reverse the inevitable emergence of resistance.

Type 5 17 -hydroxy steroid dehydrogenase, also known as aldo-keto reductase 1C3 (AKR1C3) acts downstream in the steroidogenesis pathway and plays a pivotal role in the pathogenesis and progression of CRPC by catalyzing the conversion of weak androgen precursors to the potent AR ligands: testosterone (T) and 5a-dihydrotestosterone (5a-DHT) (23). Also known as prostaglandin (PG) F synthase, AKR1C3 catalyzes the conversion of PGD2 to l ip-PGF2a and PGF2a prostanoids (24). An increase in PGF2a leads to activation of the FP receptor and consequently induces proliferation and radiation resistance in prostate cancer cells (25).

Clinically, AKR1C3 has been shown to be the most upregulated steroidogenic enzyme in CRPC patients (26). Apart from inducing a CRPC phenotype, AKR1C3 also mediates resistance to ENZ and AA by providing a source of intratumoral androgens and this resistance can be surmounted by indomethacin (INDO) a specific AKR1C3 inhibitor that also inhibits COX isozymes (27,28). As the enzyme acts at the final steps of the androgen synthesis pathway in the prostate (16), AKR1C3 inhibitors would not cause the accumulation of DOC in the adrenal gland and would not have to be co-administered with prednisone. These properties make AKR1C3 an attractive target for managing CRPC disease progression as well as countering therapeutic drug resistance. The related isoforms AKR1C1 and AKR1C2 share high homology with AKR1C3, function to eliminate DHT, and should not be inhibited (29). Numerous AKR1C3 inhibitors with diverse scaffolds are known however, none have made their way into the clinic (30-32), Considerable interest has developed in the role of AKR1C3 in a variety of cancers of the breast (33), lungs (34) and colon (35).

Herein, the inventors report on the actions of a novel, potent, isoform selective and metabolically stable AKR1C3 inhibitor, KV-37 (FIG. 20A) (36-38), in a range of prostate cancer cell lines and a xenograft model. The inventors have previously reported AKR1C3 inhibitors that act synergistically with etoposide and daunorubicin as chemotherapeutic agents in a panel of leukemia cell lines (38). The AKR1C3 inhibitor KV-37 exerts high synergistic drug interaction in combination with ENZ, which is superior to that seen with INDO. Mechanistic studies reveal that KV-37 causes apoptotic cell death in ENZ-resistant prostate cancer cell lines with a consequent reduction in PSA levels and in vivo studies demonstrate a >50% reduction in tumor growth without observable toxicity. Cell Culture and Reagents. 22Rvl and LNCaP cells were purchased from American Type Culture Collection (ATCC, Manassas, VA) and cultured in RPMI 1640 supplemented with 10% FBS, 100 U/mL penicillin and 0.1 mg/mL streptomycin (39). LNCaPlC3 cells overexpressing AKR1C3 were generated by stable transfection of AKR1C3 plasmid as previously described (12). WPMY-1 cells were purchased from ATCC and maintained in DMEM media supplemented with 5% FBS, 100 U/mL penicillin and 0.1 mg/mL streptomycin. Where indicated, cells were also cultured in charcoal stripped (CSS) media prepared by supplementing RPMI 1640 without phenol red with charcoal stripped FBS. All cells were maintained at 37oC in a humidified incubator with 5% carbon dioxide. Enzalutamide (ENZ) or MDV3100 (catalog no. 50-101-3979) and indomethacin (INDO) (catalog no. AAA1991006) were purchased from Fisher Scientific. Stock solutions of ENZ, INDO and KV-37 were prepared in DMSO and were serially diluted for cell culture treatments maintaining the final DMSO concentration at less than 1%.

Inhibition of Testosterone Production by AKR1C3 Inhibitors. Systems (200 μΕ) containing 100 mM potassium phosphate pH 7.0, 0.9 mM NADPH, 1.2 - 40 μΜ 4-androstene-3,17-dione (A4-AD) (containing 2.6 nM [3H]-4-androstene-3,17-dione), KV-37 (0 -10 μΜ), and 0.3 - 10 μΜ inhibitor plus 1.65 μΜ AKR1C3 were incubated at 37 oC, and samples were prepared as previously reported (40).

Stability Testing of AKR1C3 Inhibitors. Baccharin, KV-37 and a related ester analogue KV-32 (2 μΜ solution in DMSO) were incubated with male CD-I murine liver S9 fractions containing a NADPH generating system for 0 - 240 minutes. Reactions were quenched with 0.5 mL (1 : 1) of acetonitrile (ACN) containing 0.2% formic acid and 100 ng/mL Internal Standard (IS) (final cone. = 50 ng/mL). Samples were vortexed for 15 seconds, incubated at RT for 10 minutes and spun for 5 minutes at 2400 rpm. Supernatant (0.9 mL) was then transferred to an eppendorf tube, chilled and centrifuged for 5 minutes at 13,200 rpm. Supernatant (800 μί) was transferred to a HPLC vial and was then analyzed by Qtrap 4000 mass spectrometer using the following parameters: Ion Source/Gas Parameters: curtain gas (CUR) = 35, collisionally activated dissociation (CAD) = Medium, ionspray voltage (IS) = 4500, temperature (TEM) = 600, nebulizing gas GS1 = 70, drying gas GS2 = 70. Buffer A: dH20 + 0.1% formic acid; Buffer B: ACN + 0.1% formic acid; flow rate 1.5 ml/min; column Agilent C18 XDB column, 5 micron packing 50 X 4.6 mm size; 0 - 1 min 97% A, 1 - 2.5 min gradient to 99% B, 2.5 - 3.5 min 99% B, 4 - 4.1 min gradient to 97% A, 4.1 - 4.5 min 97% A; IS: Warfarin (in MeOH, transition 307.3 to 160.9). Ion transitions followed were 363.1 [M-H] to 186.9 for baccharin and KV-32, and 362.1 [M-H] to 318.1 for KV-37.

Cell Viability Assays. Cells were seeded at a density of 10,000 cells/well in 96-well plates and were incubated in either normal media (24 h) or charcoal stripped serum (CSS) media (48 h). Treatments with ENZ, INDO, KV-37 or combinations of ENZ and KV-37 were made with or without 10 nM A4-AD (AKR1C3 substrate) and incubated at the indicated time points (24, 48, 72 and 96 h). For pretreatment experiments, cells were treated with KV-37 for 24 h followed by the addition of ENZ and incubated for further 72 h. Cell viability was determined by the MTS tetrazolium dye assay as described previously (38).

Inhibition of Testosterone Production in LNCaP-AKRlC3 Cells. LNCaPlC3 cells (1.5 x 106 cells per well) were placed in 2 mL phenol red-free RPMI, 5% CD-FBS, 2 mM L-glu, 1% P/S. Cells were incubated with DMSO, or 10 μΜ or 30 μΜ KV-37 for 30 min at 37 °C. After the pre -incubation, 100 nM 3H A4-AD final concentration was added to the wells and cells were incubated for 24 h. Cell media was transferred into labeled borosilicate glass tubes after 48 h and extracted with 2 mL ethyl acetate. Samples were vortexed for 30 s and placed in a -20 °C freezer for 1 h to separate the phases. The frozen samples were allowed to thaw at room temperature for 10 min and centrifuged for 20 min before the organic phase was extracted and the process repeated. The 4 mL organic layer extract was then dried under vacuum for radiochromatography. The aqueous fractions were dried under vacuum for 30 min to evaporate any leftover organic solvent residue. 1% glacial acetic acid aqueous solution (25 μΚ) was added to the samples to adjust the pH to 6.5, followed by addition of 18 μL of 25 U^L E.Coli β- glucuronidase. Samples were placed in a water bath at 37 °C for 24 hr. Samples were then extracted as before. All samples were resuspended in 100 μΐ. of ethyl acetate and vortexed for 30 s to mix. Using 10 μΐ. of capillary tubes, each sample was spotted onto a multi-channel UNIPLATE 20 x 20 cm TLC plate and analyzed as described before.

Apoptosis Assay. AnnexinV/FITC apoptosis assay was performed using a kit and according to the manufacturer's instructions (BD Biosciences, catalog no. 556547). Cells were seeded at a density of 0.2 x 106 cells/well in 24- well plates and incubated in CSS media for 48 h followed by treatment with KV-37 for 48 and 72 h. For pretreatment experiments, cells were treated with KV-37 for 24 h followed by the addition of ENZ and incubated for a further 72 h. After appropriate treatments, the samples were analyzed by flow cytometery (Accuri C6, Ann Arbor, MI, USA).

Western Blotting. Whole cell lysates were prepared using 4% (w/v) CHAPS in urea-tris buffer. Protein was quantified and electrophoresed as described previously (41). The membranes were probed with primary antibodies against AR (Cell Signaling #5153P, rabbit mAb), PSA (Cell Signaling #5877S, rabbit mAb), AKR1C3 (Sigma #A6229, mouse mAb), C-PARP (Cell Signaling #5625S, Rabbit mAb), C- caspase3 (Cell Signaling #9661S, rabbit mAb) and Actin (Sigma #A5441, mouse mb). All the antibodies from Cell Signaling were diluted 1 : 1000, AKR1C3 (1:500) and actin (1:2000).

Tumor Xenograft and Pharmacokinetic Study. All animal experiments were carried out according to approved Institutional Animal Care and Use Committee protocols at the University of Texas Southwestern Medical Center (Dallas, TX). Eighteen 6-8 week old female NOD-SCID mice (low circulating testosterone) were implanted with 4 x 106 22Rvl cells in a volume of 0.1 mL in the left flank. When tumor volume reached -100 mm3 (day 13), mice were randomly divided into two groups. One group was administered 20 mg/kg KV-37 QD intra peritoneal and the other group was given vehicle control (10% DMSO, 20% PEG400, 0,5% tween 80, 69.5% carbonate buffer pH = 9.2). Tumor volumes were measured twice a week with Vernier calipers and tumor volume was calculated as (L*W2)*3.14)/6. On day 34, mice were humanely euthanized and tumors were collected, weighed and frozen in liquid nitrogen after taking pictures. Whole blood was collected in an eppendorf tube with ACD anti-coagulant for plasma separation for pharmacokinetic evaluation of KV-37.

Pharmacokinetic Evaluation of KV-37: For Standards, 98 μΐ. of blank plasma was added to an eppendorf and spiked with 2 μΐ. of IS (Warfarin). For QCs, 98.8 μΐ. blank plasma was added to an eppendorf and spiked with 1.2 μΐ. of IS. 100 μΐ. of plasma was mixed with 200 μΐ. of methanol containing 0.15% formic acid and 37.5 ng/mL IS (IS final cone. = 25 ng/mL). The samples were vortexed for 15 s, incubated at room temperature for 10 min and spun at 13,200 rpm in a standard microcentrifuge. The supernatant was then analyzed by LC- MS/MS as described earlier.

Statistical Analyses and Quantification of Degree of Synergism. Experiments were repeated at least thrice and the statistical significance was calculated using the Student's t test. A p value of < 0.05 was considered statistically significant. IC50 values were calculated by GraphPad prism software. Combination of KV-37 with ENZ was analyzed by CompuSyn software (Biosoft) based on the Chou- Talalay method. Combination Index (CI) and Dose Reduction Index (DRI) values were generated to evaluate the degree of synergistic drug interaction.

It was found that inhibitors of AKR1C3 from various structural classes (flavones (30), jasmonates (31) and NSAID's (23,33)) have previously been described. The inventors adopted a cinnamic acid derivative 'baccharin' and conducted structure-activity relationship (SAR) studies to identify lead AKR1C3 inhibitors (37,38). The cinnamic acid derivative KV-37 (FIG. 1A) was chosen for further studies as it demonstrated potent AKR1C3 inhibition (IC50 = 66 nM) and selectivity (109-fold over AKR1C2) (38). In order to delineate the preliminary mechanism of action, the inventors tested its mode of AKR1C3 inhibition. The inventors found that KV-37 displayed competitive enzyme inhibition versus AKR1C3 when μ4-Αϋ was used as substrate, yielding a Ki value of 3.0 μΜ for the E.NADPH.KV-37 complex. The difference between this Ki value and the IC50 value seen in the preliminary inhibitor screen is consistent with the lower Ki value for the E.NADP+. inhibitor complex which is seen with other AKR1C3 inhibitors when they are screened in the oxidation direction (FIG. 201) (40). The inventors also examined the mode-of-action of KV-37 in androgen-dependent 22Rvl cells (high AKR1C3 expression) and LNCaP cells (low AKR1C3 expression). The 22Rvl cell line shows increased expression of AKR1C3 when grown in CSS media and possesses intrinsic resistance to ENZ and AA (27). LNCaP cells stably overexpressing AKR1C3 (LNCaP 1C3) were used to further validate the effect of KV-37 on the target (12). Further, WPMY-1 cells, a non-malignant prostate stromal cell line, devoid of AKR1C3 expression (FIG. 20J, 20K), were employed to evaluate the selective cytotoxicity of KV-37.

FIG. 201 shows Competitive inhibition of NADPH dependent reduction of A4-androstene-3,17-dione mediated by AKR1C3 by KV-37. KV-37 acts as a competitive Inhibitor in the conversion of [3Η]Δ4- androstene-3,17-dione to testosterone. Increasing concentrations of KV-37 (0-10 μΜ) were used to inhibit the NADPH dependent conversion of fixed concentrations of [3H]A4-androstene-3,17-dione to testosterone catalyzed by recombinant AKR1C3 as measured by radiochromatography.

FIG. 20J. 22Rvl and LNCaPlC3 cells overexpress AKR1C3 whereas LNCaP and WPMY-1 exhibit low AKR1C3 levels. (FIG. 20J) Relative expression of AKR1C3 across prostate cancer cell lines. (FIG. 20K) Culture of 22Rvl cells in CSS media upregulates AKR1C3 expression levels. (NM, normal media; CSS, charcoal stripped serum media).

KV-37 inhibits AKR1C3 activity in prostate cancer cell lines by inhibiting the conversion of A4-AD to testosterone. KV-37 was used to inhibit the production of testosterone in LNCaPlC3 cells following β- glucuronidase treatment of the aqueous phase. At a concentration of 10 μΜ, >80% inhibition of testosterone production is blocked and the residual testosterone produced is that seen in untransfected LNCaP cells (FIG. 21A to 21C).

FIG. 21A to 21C. KV-37 inhibits conversion of [3H]A4-androstene-3,17-dione to testosterone in LNCaP- 1C3 cells. LNCaP-lC3 cells (1.5 x 106 cells per well) platted in phenol red-free RPMI, 5% CSS-FBS, 2 mM L-glutamine, 1% P/S and were with DMSO or 10 μΜ KV-37 for 30 min at 37 °C. After the preincubation, 100 nM [3H]A4-androstene-3,17-dione final concentration was added to the wells and cells were incubated for 24 h. FIG. 21A is solvent control; FIG. 21B contains 10 μΜ KV-37 and FIG. 21C are LNCaP control cells treated with DMSO. The peak at 90 mm is androsterone and the peak at 120 mm is testosterone liberated after β-glucronidase treatment. The data reveal almost complete inhibition of AKR1C3 mediated testosterone production.

KV-37 exhibits excellent plasma stability above that of the parent and other derivatives. Baccharin undergoes rapid hydrolysis to yield the inactive phenol drupanin (AKR1C3 IC50 = 15 μΜ) (37). In order to compare the hydrolytic stability of lead compounds, baccharin and its derivatives were subjected to incubation with mouse S9 fractions in the presence of phase I co-factors from 0-240 min. Aliquots were withdrawn and analyzed by LC-MS at various time points. As expected, baccharin and a related ester analogue (KV-32) were readily hydrolyzed (FIG. 22A to 22C). The amide-based inhibitor KV-37 displayed remarkable stability (tl/2 = >240 min).

FIG. 22A-22C: Metabolic instability of (FIG. 22 A) Baccharin and (FIG. 22B) ester derivative KV-32 on incubation with mouse S9 fractions. FIG. 22C shows the half-life of baccharin and derivative AKR1C3 inhibitors upon incubation with human S9 liver fractions.

AKR1C3 inhibitor KV-37 exhibits greater cytotoxicity to prostate cancer cell lines compared to baccharin. Baccharin and its analog KV-37 were screened for cytotoxic effects in a panel of human prostate cancer cell lines (LNCaP, 22Rvl and LNCaPlC3). Baccharin consistently displayed no toxicity among all the cell lines tested, up to concentrations as high as 100 μΜ (FIG. 23A to 23C). This is in agreement with previous studies (38). However, treatment with KV-37 demonstrated greater cytotoxicity in a dose and time- dependent manner in androgen dependent 22Rvl and LNCaP cell lines. The cytotoxic effect was greater in 22Rvl cells due to the higher expression of AKR1C3 as compared to the LNCaP cell line (FIG. 20A-H). For 22Rvl cells, a significant decline in IC50 values (p = 0.0015, O.0001, <0.0001 at 24, 48 and 72 h respectively) was observed after KV-37 treatment when the cells were cultured in CSS media as compared to normal media (FIG. 20B, 20C, 20H). This is attributable to the overexpression of AKR1C3 when cells are grown in media devoid of androgens (supplementary FIG. S2). This drives the cellular phenotype to more closely resemble clinical castrate conditions, where the cancer cells are dependent on AKR1C3 for survival and proliferation. Culture in CSS media supplemented with an AKR1C3 substrate 10 nM A4-AD lead to a slight reduction in cytotoxic effect and a significant increase in IC50 values (p = O.0001, <0.0009, <0.0001 at 24, 48 and 72 h respectively) as compared to those observed in non-supplemented CSS media (FIG. 20C, 20E, 20H). Addition of 10 nM A4-AD to CSS culture mimics the serum level of this androgen in CRPC patients (12,42,43). As A4-AD is a substrate for AKR1C3, this observation suggests that the reduced cytotoxic activity of KV-37 is due to the enzymatic formation of T and DHT and corroborates AKR1C3 as the inhibitor target. Cytotoxic activity of KV-37 was also evaluated in normal media supplemented with 10 nM A4-AD as a control experiment to directly measure the difference in dose responses in normal and CSS media (FIG. 20D, 20H).

FIGS. 23A to 23C: Baccharin does not exert cytotoxicity on prostate cancer cell lines. Percentage cell viability of (FIG. 23A) LNCaP, (FIG. 23B) 22Rvl and (FIG. 23C) LNCaPlC3 cells cultured in CSS media after baccharin treatment at indicated concentration and time points. Data shown as mean ± SD of at least three independent experiments, n=6.

AKR1C3 inhibitor KV-37 sensitizes ENZ resistant prostate cancer cells to ENZ by exerting a synergistic drug effect. The 22Rvl cell line is intrinsically resistant to ENZ (27). The dose-response curve of ENZ in 22Rvl cells displays increasing resistance upon culture in CSS media (supplementary FIG. S6), which is accompanied by an increase in AKR1C3 expression (FIGS. 20J and 20K). LNCaP cells that are sensitive to ENZ-induced cytotoxicity were used as controls to compare the effect of KV-37 in combination with ENZ. To test whether the sensitivity of 22Rvl cells to ENZ could be restored with KV- 37, 22Rvl and LNCaP cells were pre-treated with KV-37 for 24 h followed by exposure to ENZ. The combination demonstrated a remarkable synergistic effect in 22Rvl cells at both 48 and 72 h post ENZ exposure in normal, as well as CSS media (CI = 0.19 and 0.07 respectively) (FIG. 25A-25C, I). Concentrations as low as 1 μΜ of KV-37 were capable of sensitizing 22Rvl cells to only 1 μΜ of ENZ and reduced viability by more than 50%. Either agent employed alone, did not exert any cytotoxic effect. Among cultures supplemented with 10 nM A4-AD in normal and CSS media, the synergistic drug interaction was maintained (CI = 0.33 and 0.10 respectively) (FIG. 25D-25F, 251). Quantification of degree of synergism was made using the Chou-Talalay method (44). Up to a 200-fold reduction in ENZ dosing was achieved in 22Rvl cells (FIG. 21), LNCaP cells however, due to their meager expression of AKR1C3, displayed a lack of synergistic drug effect at the concentrations tested, among both normal and CSS media, and the interaction was merely additive (CI = 1.12 and 1.14 respectively) (FIG. 2G-I). On the contrary, co-treatment experiments did not show any adjuvant effect in either cell line cultured in normal or CSS media, with or without A4-AD supplementation (FIGS. 26A-26H). This observation suggests that the activity of AKR1C3 needs to be inhibited prior to ENZ treatment in 22Rvl cells for the therapeutic drug effect.

FIGS. 24A to 24D: Percentage cell viability of ENZ at indicated time points in (FIG. 24A) LNCaP cells cultured in indicated growth media (FIG. 24B) 22Rvl cells cultured in CSS media (FIG. 24C) 22Rvl cells cultured in CSS media supplemented with 10 nM A4-androstene-3,17-dione (FIG. 24D) 22Rvl cells cultured in normal media supplemented with 10 nM A4-androstene-3,17-dione. Data shown as mean ± SD of at least three independent experiments, n=6.

FIGS. 26A to 26H: Co-treatments of KV-37 with ENZ do not exert synergistic cytotoxic effects in LNCaP and 22Rvl cells. Percentage cell viability of prostate cancer cells after combination treatment with KV-37 and ENZ in (FIGS. 26A-26C) LNCaP cells at indicated time points cultured in indicated growth media (FIGS. 26D-26E) 22Rvl cells cultured in indicated growth media at 72 h and (FIGS. 26F- 26H) 22Rvl cells at indicated time points cultured in indicated growth media supplemented with 10 nM A4-androstene-3,17-dione. Data shown as mean ± SD of at least three independent experiments, n=6.

FIGS. 25A to 251. Pre-treatment with KV-37 sensitizes prostate cancer cell lines to ENZ cytotoxicity. Percentage cell viability of prostate cancer cells when pre-treated with KV-37 for 24 h followed by ENZ treatment at indicated concentrations and time points in (FIG. 25 A) 22Rvl cells cultured in normal media (FIG. 25B) and (FIG. 25C) 22Rvl cells cultured in CSS media (FIG. 25D) 22Rvl cells cultured in normal media supplemented with 10 nM A4-androstenedione (FIG. 25E) and (FIG. 25F) 22Rvl cells cultured in CSS media supplemented with 10 nM A4-androstenedione (FIG. 25G) LNCaP cells cultured in normal media and (FIG. 25H) LNCaP cells cultured in CSS media. (I) Quantification of the degree of synergism. Combination index (CI) and dose reduction index (DRI) values for KV-37 and ENZ combination treatments in prostate cancer cells. CI and DRI indices generated using CompuSyn software. Data shown as mean ± SD of at least three independent experiments, n=6.

AKR1C3 overexpression in LNCaP cells confers resistance to ENZ cytotoxicity that is reversed upon KV-37 treatment. The LNCaP 1C3 cell line, stably overexpressing AKR1C3, was employed to evaluate the activity of KV- 37 alone and in combination with ENZ to further validate AKR1C3 as the target. KV- 37 induced a dose- and time -dependent reduction in cell viability of LNCaPlC3 cells (FIG. 27A and table insert). The cytotoxic drug effect increased further as compared to 22Rvl and low AKR1C3 expressing LNCaP cells at all time points tested. These observations demonstrate that the bioactivity of KV-37 is AKRlC3-dependent and further corroborates AKR1C3 as the compound's target. Next, a dose- response curve of ENZ was evaluated in LNCaP 1C3 cells that revealed the generation of a resistant phenotype as observed in previous findings.(27) The 72 h IC50 of ENZ increased to 150 μΜ in LNCaPlC3 cells as compared to 50 μΜ in sensitive LNCaP cells (FIG. 27B and FIGS. 24A to 24D). To overcome this drug resistance, cells were treated with a combination of KV-37 and ENZ as co-treatments for 72 h or as 24 h pre-treatments with KV-37 followed by ENZ exposure for a further 72 h. Co- treatment experiments showed a moderate degree of drug synergism (CI = 0.54) (FIG. 27C and table insert). Among the pre-treatment experiments, a very high degree of synergistic dug interaction was observed (CI = 0.14) and concentrations as low as 1 μΜ of KV-37 were able to sensitize the cells to ENZ- induced cytotoxicity. As a result, the effective ENZ concentration to induce cytotoxicity was reduced by 25-fold and yielding an IC50 of 8.19 μΜ for the drug combination (FIG. 27D and table insert). These findings strongly suggest that KV-37, by virtue of its AKR1C3 inhibiting properties, is able to re-sensitize ENZ-resistant prostate cancer cells that are high expressers of AKR1C3 towards ENZ cytotoxicity.

FIGS. 27A to 27D. AKR1C3 overexpression in LNCaP cells (LNCaPlC3) increases the cytotoxic activity of KV-37 and induces resistance to ENZ that is overcome by pre-treatment with KV-37. Percentage cell viability of LNCaPlC3 cultured in CSS media after (FIG. 27A) KV-37 treatment at indicated time points and concentrations (table insert showing the IC50 values) (FIG. 27B) ENZ treatment at indicated time points and concentrations (FIG. 27C) co-treatment with KV-37 and ENZ for 72 h and (FIG. 27D) pre-treatment with KV-37 followed by ENZ exposure for 72 h. Table insert showing the parameters for quantifying the degree of synergism. Data shown as mean ± SD of at least three independent experiments, n=6.

KV-37 induces cell death in prostate cancer cells via apoptosis. To elucidate the primary mechanism of cell death, 22Rvl and LNCaPlC3 cells cultured in CSS media were treated with increasing doses of KV- 37. After 48 and 72 h time periods post treatment, the cells were harvested and stained with AnnexinV/PI to measure apoptotic cell percentage. The percentage of the apoptotic cell population increased with KV- 37 concentration in a dose- and time -dependent manner (FIG. 28A). Consistent with the results from the cytotoxicity screening, the effect was significantly greater in the LNCaPlC3 cell line as compared to the 22Rvl cells at both time points (p = <0.05 at 25 μΜ KV-37 and <0.003 at 50 μΜ KV-37), underscoring the significance of AKR1C3 overexpression in prostate cancer. In order to further corroborate these findings, Western blot analysis was conducted after inhibitor treatment following an identical dosing schedule. The results, in agreement with AnnexinV/PI assay consistently show a dose-dependent increase in the levels of C-caspase3 and C-PARP with higher expression at 72 h as compared to 48 h incubation time, among both 22Rvl and LNCaPlC3 cell lines (FIG. 28C). Taken together, this data strongly suggests apoptosis as the primary mechanism of cytotoxicity for KV-37.

Combination of KV-37 with ENZ potentiates the degree of apoptosis in prostate cancer cells. To determine whether the effect of KV-37 to induce apoptosis in 22Rvl cells persists in the presence of ENZ, cells were pretreated with KV-37 followed by ENZ incubation for 72 h. The cells were subjected to apoptosis analysis by AnnexinV/PI co-staining. In 22Rvl cells, a combination of 10 μΜ KV-37 with 25 μΜ ENZ displayed a significant increase (p = <0.05) in apoptotic cell percentage as compared to 25 μΜ ENZ treatment alone, whereas a combination of 25 μΜ KV-37 with 25 μΜ ENZ displayed a highly significant (p = <0.0001) increase in apoptotic cell percentage as compared to either treatments alone (FIG. 28B, left panel). Percent apoptosis was also increased in LNCaPlC3 cells wherein both 10 μΜ and 25 μΜ KV-37 plus 25 μΜ ENZ demonstrated a significant (p = <0.05 and <0.01 respectively) increase in percent apoptosis levels than with either treatment alone (FIG. 28B, right panel). These findings were further confirmed by Western blot analysis showing a greater increase in C-caspase3 and C-PARP levels in drug combination experiments performed with 10 μΜ KV-37 and 25 μΜ ENZ in 22Rvl (FIG. 28D, left panel) and LNCaPlC3 cells (FIG. 28D, right panel). These observations complement the cytotoxicity studies of the drug combinations and further strengthen the hypothesis of apoptotic cell death induced by KV-37 in prostate cancer cells.

FIGS. 28A to 28D. KV-37 induces apoptosis in prostate cancer cells alone and potentiates the degree of apoptosis when combined with ENZ. (FIG. 28A) Dose and time-dependent increase in apoptotic cell population after treatment with KV-37 in indicated cell lines as analyzed by AnnexinV/PI co-staining. (FIG. 28B) Increase in apoptotic cell population after treatment with indicated concentrations of KV-37, ENZ and a 24 h pre-treatment combination of KV-37 and ENZ in indicated cell lines analyzed 72 h post ENZ exposure by AnnexinV/PI co- staining. (FIG. 28C) Western blot showing an increase in C-caspase3 and C-PARP levels after treatment with KV-37 at indicated concentration and time points in prostate cancer cells. (FIG. 28D) Western blot showing a greater increase in C-caspase3 and C-PARP levels with a 24 h pre-treatment combination of KV-37 and ENZ in prostate cancer cells analyzed 72 h post ENZ exposure. Data shown as mean ± SD of at least three independent experiments, n=3. *, p<0.05; **, p<0.01; ****, p<0.0001; ns, non-significant.

Molecular changes following KV-37 treatment in prostate cancer cells. Western blot analysis was conducted to measure the expression levels of AKR1C3, AR and PSA. A slight decrease in the expression level of AKR1C3 was noted in 22Rvl cells at 48 h, whereas, 72 h treatment increased AKR1C3 expression, both changes were observed at 25 μΜ and 50 μΜ KV-37 concentrations (FIG. 29A). In LNCaPlC3 cells a decrease in AKR1C3 expression was noted at only 50 μΜ concentration at 48 h. On the contrary, no change in AKR1C3 expression was observed in the LNCaPlC3 cell line at all concentrations tested at 72 h post KV-37 exposure (FIG. 29B). Since, AKR1C3 serves as a co-activator for AR (45), it was prudent to measure AR levels after treatment. The inventors observed that expression of AR complements AKR1C3 levels and was found to be decreased after 48 h of treatment, while at 72 h, no change in AR levels was observed in both 22Rvl and LNCaPlC3 cell lines. A consistent decline in PSA levels in a concentration- dependent manner was observed in both cell lines at 48 and 72 h treatments. Such findings signify a beneficial therapeutic outcome in prostate cancer after treatment with KV-37 (FIG. 29A and 29B).

Combination of KV-37 with ENZ downregulates AR expression that increases after ENZ treatment. To determine the mechanism of synergistic interaction between KV-37 and ENZ, Western blot analysis was performed. In contrast to previous reports that indicate AR degradation in 22Rvl cells (46), treatment of 25 μΜ ENZ alone increased AR expression in both 22Rvl and LNCaPlC3 cells signifying drug resistance, which in combination with 10 μΜ KV-37 reduced the expression to less than control levels (FIG. 29C and 29D). Consistent with inhibitor treatment alone, the combination produced no change in AKR1C3 expression levels. However, the combination of 10 μΜ KV-37 with 25 μΜ ENZ completely abrogates PSA expression in 22Rvl cells and reduced PSA to control levels in LNCaPlC3 cells. This data suggests apoptotic cell death as a primary mechanism of synergistic cytotoxic effect as a consequence of reduction in the activity of AKR1C3 and expression of AR.

FIGS. 29A to 29D. Molecular changes following KV-37 treatment. Treatment with KV-37 alone at indicated concentration and time points in (FIG. 29 A) 22Rvl and (FIG. 29B) LNCaPlC3 cells cultured in CSS media. Treatment with indicated concentrations of KV-37, ENZ and a 24 h pre-treatment combination of KV-37 and ENZ in (FIG. 29C) 22Rvl cells and (FIG. 29D) LNCaPlC3 cells cultured in CSS media analyzed 72 h-post ENZ exposure.

Treatment of prostate cancer cells with KV-37 does not affect AR transactivation and AR nuclear localization. KV-37 does not displace [3H]-R1881 from the AR in cell binding assays suggesting that it has no affinity for the AR. Similarly, in AR luciferase reporter gene assays no effect was seen with 10 μΜ KV-37, where 1 nM DHT is the EC50 value. The HeLa cell line which contains HeLa- AR3 A-P S A- (ARE)4-Lucl3) also expresses AKR1C3. Using an AKR1C3 substrate, 4- DAD, a blunted response is observed when compared with DHT, likely due to the conversion to T. Unfortunately, inclusion of KV- 37 in the assay resulted in interference, preventing conclusive data from being obtained.

Antitumor effect and pharmacokinetics of KV-37 in a 22Rvl xenograft model. Treatment with KV-37 at 20 mg/Kg per day in mice harboring 22Rvl xenografts significantly (p =0.0003) inhibited tumor volume by greater than 50% and tumor weight by 35% (p = 0.0179) (FIGS. 30A-30C) as compared to vehicle treated controls. No significant change in body weight was observed (FIG. 30D), indicative of a non- toxic effect. On day 34, mice were euthanized and blood collected at 10 min, 120 min and 360 min post KV-37 administration at 20 mg/Kg and pharmacokinetic parameters analyzed. The peak plasma concentration (Cmax) was determined to be 86.5 μg/mL, and Tmax, AUC, Vz/F and CL/F calculated (FIG. 30E).

FIG. 30A to 30E. KV-37 induces tumor growth inhibition in prostate cancer xenografts. Reduction in (FIG. 30A) prostate tumor volume and (FIG. 30B) prostate tumor weight in 22Rvl murine xenografts after treatment with 20 mg/Kg KV-37. (FIG. 30C) Representative images showing a reduction in tumor size after treatment with 20 mg/Kg KV-37. (FIG. 30E) Pharmacokinetic parameters determined in plasma after treatment with 20 mg/Kg KV-37.

FIGS. 31A to 31D: Indomethacin exerts a weak synergistic drug effect in LNCaPlC3 cells and KV-37 does not induce cytotoxicity alone or in combination with ENZ in WPMY-1 cells. Percentage cell viability of LNCaPlC3 cells after (FIG. 31A) treatment with indicated concentrations of indomethacin for 96 h and (FIG. 3 IB) 24 h pre-treatment with indomethacin followed by ENZ treatment for 72 h. Percentage cell viability of WPMY-1 cells after (FIG. 31C) treatment with indicated concentrations of KV-37 for 96 h and (FIG. 3 ID) 24 h pre-treatment with KV-37 followed by ENZ treatment for 72 h. Table insert showing the quantification of the degree of synergism. Data shown as mean ± SD of at least three independent experiments, n=6.

Indomethacin displays diminished cytotoxic effect and weak synergistic drug action compared to the more potent inhibitor KV-37. Indomethacin (INDO) (AKR1C3 Ki = 8 μΜ for the E.NADPH.Indomethacin complex) has been shown to reverse ENZ resistance in prostate cancer models (27). The dose-response curve of INDO showed a weak inhibition of cell viability at 96 h incubation, IC50 = 112.8 μΜ (FIG. 31 A). Further, the inventors also administered INDO as a 24 h pre-treatment to LNCaPlC3 cells followed by ENZ exposure for 72 h. A moderate synergistic drug action was observed (CI = 0.32, DRI = 6.4) (FIG. 3 IB) as compared to the very high degree of synergism with KV-37 under identical conditions (CI = 0.14, DRI = 24.8). These findings further bolster the concept that AKR1C3 inhibition by KV-37 sensitizes ENZ-resistant prostate cancer cells to the chemotherapeutic, and is superior to indomethacin

KV-37 exhibits no cytotoxicity alone, or in combination with ENZ, in WPMY-1 prostate cells. The non- malignant prostate stromal cell line WPMY-1 was chosen to evaluate the cytotoxic activity of KV-37. Consistent with the observation that WPMY-1 cells are low expressers of AKR1C3, the reduction of cell viability induced by KV-37 was minimal with 96 h IC50 = 80 μΜ. At concentrations of 1, 10 and 25 μΜ of KV-37, those used in the study of prostate cancer cells, no reduction in WPMY-1 cell viability was observed. An observation consistent with no loss of body weight in mice xenografts upon 20 mg/Kg daily dosing. Further, pre-treatment with KV-37 for 24 h followed by ENZ exposure for 72 h resulted in no loss of cell viability (FIG. 31C and 3 ID).

Prostate tumors resistant to AA and ENZ, are characterized by overexpression of steroidogenic enzymes where AKR1C3 is the most overexpressed (26,47,48). Thus, in situ or intratumoral androgen biosynthesis is a predominant factor of therapeutic failure with AR antagonists (13,49). Overexpression of AKR1C3 by stable transfection in prostate cancer cells imparted ENZ resistance which was overcome by AKR1C3 knockdown by shRNA. Indomethacin, a weak AKR1C3 inhibitor, was also able to rescue xenografts from ENZ and AA resistance (27,28). Continuing the efforts to identify potent and selective AKR1C3 inhibitors the inventors synthesized and characterized KV-37, a nanomolar inhibitor of AKR1C3 with > 100-fold isoform selectivity and metabolic stability (38). The inventors demonstrate the synergistic effects of KV-37 with ENZ on prostate cancer cell cytotoxicity is much greater than that seen with INDO, and that the effects of KV-37 are mediated by AKR1C3 inhibition.

The inventors demonstrate that KV-37 inhibits the activity of AKR1C3 in prostate cancer cells by inhibiting the conversion of A4-androstenedione to testosterone. Crucially, KV-37 exerts a preferential cytotoxic effect in AKR1C3 overexpressing 22Rvl and LNCaPlC3 cells as compared to the low expressing LNCaP cell line and non-malignant WPMY-1 cells. Furthermore, culture of 22Rvl cells in CSS media, that is devoid of androgens, upregulates AKR1C3 expression further and results in greater susceptibility to KV-37-induced cytotoxicity. Since the physiological androgen level in clinical castrate conditions is of the order of 1-10 nM, CSS was supplemented with 10 nM A4-androstenedione to further mimic the CRPC phenotype (43). KV-37 displayed an equally robust inhibition of cell viability in such cultures. The 22Rvl cell line is inherently resistant to ENZ, whereas LNCaP cells became resistant to ENZ when AKR1C3 was stably expressed in this cell line. Pre- treatment with KV-37 restored the sensitivity of 22Rvl cells to ENZ and provided strong synergistic effect resulting in a 200-fold reduction in chemotherapeutic dosing under conditions that mimic the CRPC disease phenotype. The strong synergistic effect was maintained in LNCaP 1C3 cells upon pre -treatment with KV-37. A moderate synergistic effect was also observed in these cells if KV-37 was co-administered with ENZ. By contrast, as LNCaP cells are low expressers of AKR1C3, only an additive effect was observed, an observation that may be ascribed to the general cytotoxicity of KV-37 towards cancer cells as evidenced previously in leukemic cell lines (38).

Insights into the mechanism of apoptosis mediated by KV-37 were obtained by measuring an increase in the apoptotic markers C-caspase3 and C-PARP, as well as a dose-dependent increase in annexinV/PI after KV-37 treatment. The observation that percent apoptotic cells were greater in LNCaPlC3 cells at any given concentration, compared to 22Rvl cells, corroborates AKR1C3 as the target of KV-37. In combination drug treatments, 25 μΜ ENZ was employed, as this corresponds to the minimum steady state plasma concentration of 12 μg/mL of the drug; the physiological concentration achieved clinically in prostate cancer patients at 150 mg/day dosing regimen (17). A sub-therapeutic concentration of KV-37 (10 μΜ), that exerts no more than 20% reduction in prostate cancer cell viability, was chosen for the drug combination treatments. In combination drug treatments, annexinV/PI staining demonstrated a significant increase in the percentage of apoptotic cells compared to either treatment alone, and was confirmed by an increase in C-caspase3 and C-PARP levels.

These data indicate that apoptotic cell death is a primary mechanism of the synergistic cytotoxic drug effect. Androgen-dependent gene expression was analyzed post KV-37 treatment and a dose-dependent reduction in PSA levels was observed. Although the activity of AKR1C3 was inhibited by KV-37, the protein expression levels either remained unchanged, or slightly increased in 22Rvl cells, post treatment, indicating a feed-back increase in AKR1C3 expression. Interestingly, the inventors observed an increase in the AR expression levels after treatment with ENZ alone in both 22Rvl and LNCaP 1C3 cell lines, which is one of the signatures of drug resistance. Combination of ENZ with KV-37 reduced AR expression to control levels or less. Further, treatment with KV-37 alone in 22Rvl murine xenografts reduced tumor volume by more than 50%, whereas no change in mouse body weight was observed. In order to compare the degree of synergistic drug interaction exhibited by the weak AKR1C3 inhibitor indomethacin (Ki = 8 μΜ) with KV-37 (Ki = 3.0 uM), pre-treatment experiments with indomethacin were conducted in LNCaPlC3 cells followed by ENZ treatment that revealed a moderate degree of drug synergism, much lower than that achieved with KV-37. This study serves as proof-of-concept that AKR1C3 inhibition has the potential to overcome ENZ resistance and corroborates previous findings (27). Further, the inventors also analyzed the activity of KV-37 alone and in combination with ENZ in the non-malignant human prostate stromal cell line WPMY-1. No reduction in cell viability up to 25 μΜ was observed, whereas no cell viability reduction in combination experiments was noted, indicating selectivity to cells overexpressing AKR1C3.

In example 2, the inventors show that KV-37 can be used as a monotherapy for castration-resistant prostate cancer since it retards ENZ resistant prostate cancer cell growth and induces apoptosis. The structurally novel AKR1C3 inhibitor KV-37 synergizes with ENZ and re-sensitizes ENZ-resistant prostate cancer cells to the action of a chemotherapeutic agent.

Example 3. Potent and Highly Selective AKR1C3 Inhibitors with Chemotherapeutic Potentiation Effect in Acute Myeloid Leukemia (AML) and T-cell Acute Lymphoblastic Leukemia (T-ALL)

Aldo-keto reductase 1C3 (AKR1C3) catalyzes the synthesis of 9a,l i -prostaglandin (PG) F2a and PGF2a prostanoids that sustain the growth of myeloid precursors in the bone marrow. Moreover, AKR1C3 confers chemotherapeutic resistance to the anthracyclines: first-line agents for the treatment of leukemias. The enzyme is overexpressed in Acute Myeloid Leukemia (AML) and T-cell acute lymphoblastic leukemia (T ALL). Highly homologous isoforms AKR1C1 and AKR1C2 are required for normal steroid metabolism, inhibition of which is undesirable. The inventors report herein, the identification of novel AKR1C3 inhibitors that demonstrate exquisite isoform selectivity for AKR1C3 over the other closely related isoforms in the order of >2800. Biological evaluation of the inventors' isoform selective inhibitors revealed a high degree of synergistic drug action in combination with the clinical leukemia therapeutics daunorubicin and cytarabine in in vitro cell models of AML and primary patient-derived T-ALL. The developed compounds exhibited a > 100-fold dose reduction index that resulted in complete resensitization of a daunorubicin-resistant AML cell line to the chemotherapeutic and reduction of the IC50 of cytarabine from 40 nM to <1 nM.

The natural product Baccharin, extracted from honeybee propolis has been shown to potently and selectively inhibit AKR1C3 with an IC50 of 0.11 μΜ and a fold selectivity of 500 over AKR1C2.23 The inventors adopted this natural structural scaffold and have previously reported the synthesis and a preliminary structure-activity relationship (SAR) for AKR1C3 inhibition.24 The dihydrocinnamoyloxy moiety of the hit scaffold is reported as a structural prerequisite for AKR1C3 inhibition,26 and other groups have synthesized potent AR1C3 inhibitors based on this scaffold.25 However, the presence of an ester linkage provides for the hydrolytic lability of baccharin making these analogues unsuitable leads for drug discovery. Hydrolysis of the ester results in formation of the known phenol drupanin, with complete abrogation of AKR1C3 inhibitory activity (unpublished data). Theprior studies have reported the design, synthesis and evaluation of potent AKR1C3 inhibitors bearing a more stable amide bioisostere. These AKR1C3 inhibitors exhibit a six-fold potentiation of etoposide and a ten-fold potentiation of daunorubicin in AML cell lines.27 However, the selectivity, while significantly improved above that of MPA (0.66-fold), remained relatively low (109-fold). Continuing theefforts to identify highly isoform selective AKR1C3 inhibitors the inventors herein report the discovery of a library of optimized compounds possessing >2800-fold selectivity for AKR1C3 inhibition, with retention of inhibitory potency in the nanomolar range. Further, the inventors demonstrate that the highly isoform selective AKR1C3 inhibitors provide potentiation up to 100-fold of the clinical chemotherapeutics daunorubicin and cytarabine across a panel of AML cell lines and in primary patient-derived T-ALL cells.

Chemistry. Based on the baccharin structural scaffold, four different classes of analogues were synthesized and evaluated for AKR1C3 inhibition activity and fold selectivity towards the other highly homologous AKR isoforms (Figure 1). To explore modifications of the dihydrocinnamoyloxy moiety, Class I compounds, bearing an ester or amide link to the phenyl ring with changes in the carbon spacer length were synthesized. Class I-A compounds contained methoxy or flourine substituents on the B ring. The substitution pattern of the carboxylic acid containing side chain was changed to the meta position relative to the side chain amide in Class II analogues. Similar to Class I-A compounds, class II-A analogues contained alcohol, methoxy, tosyl or flourine substitution on the B ring. In order to explore the significance of the carboxylic acid side chain, class III analogues bearing boronic acid bioisosteres were synthesized. Further, the side chain substitution pattern on the A ring was modified in Class III compounds. Finally, class IV compounds bearing a 1,3,5-all meta side chain substituent pattern on the A ring were synthesized. Class IVA compounds featured changes in spacer length and substituents on the B ring.

Figure 32 shows a SAR strategy map for the design of Baccharin derivatives of the present invention. Baccharin (1), compounds 8b-n (class I and I-A) and 7-7a (class III) were synthesized using a modified literature procedure.35 Nucleophilic substitution of commercially available 4-iodophenol (2) with prenyl bromide yielded the alkylated intermediate 3,36 which was subsequently esterified with an appropriately substituted acid chloride (4a-n) to yield ester intermediates (5a-n). Mizoroki-Heck37, 38 coupling of the aryl iodide intermediates (5a-n) with tert-butyl acrylate or vinyl boronic acid pinacol ester using Pd(OAc)2 and PPh3 as a catalyst-ligand complex produced α,β-unsaturated olefins 6a-n and 7 respectively. Chemoselective hydrolysis of the tert-butyl ester,39 of 6a-n afforded baccharin (1) and derivatives 8b-n, whereas hydrolysis of the pinacol ester afforded boronic acid 7a (Scheme 1).

Scheme 1: Synthesis of baccharin (1), substituted ester derivatives of class I, I-A and boronic acid derivatives of class III. The reaction sequence was then modified where p-iodoaniline (9) was regioselectviely brominated using a modified literature procedure that afforded 10.40 Exploiting the greater reactivity of iodide over bromide in Mizoroki-Heck38 couplings, 10 was selectively coupled with tert-butylacrylate yielding the intermediate aniline 11. Coupling with the corresponding acid chloride (12a-e) gave amide intermediates (13a-e). A palladium-catalyzed Suzuki-Miyaura41 cross-coupling reaction installed the prenyl side chain that yielded intermediates42 (14a-e) which were underwent chemoselective hydrolysis of the tert-butyl ester to afford the final compounds (15a-e) of class III (Scheme 2).

Scheme 2: Synthesis of amide bioisosteres of class I ester derivatives. The substitution pattern of the side chains on the baccharin A ring was modified in class II compounds in which the ester chain was substituted to the meta-position relative to the carboxylic acid side chain. Commercially available m- coumaric acid (16) was protected as the methyl ester and subsequently brominated, with column chromatography providing access to the desired regioselectivity in 35% yield. The brominated intermediate (17) was deprotected under basic conditions to yield compound 17a which was followed by esterification of the phenol moiety using phenylpropionyl acid chloride to yield ester derivative 18. Suzuki-Miyaura41 reaction with the appropriately substituted boronic acid pinacol ester afforded prenyl and allyl derivatives (19a, b) of class II (Scheme 3).

Scheme 3: Synthesis of meta-substituted ester derivatives of class II. The amide bioisosteres 26a-l, 28 (class II, II-A) and 24 (class III) were accessed through Mizoroki-Heck38 reaction of commercially available 4-bromo-2-iodoaniline (20) with tert-butyl acrylate or vinyl boronic acid pinacol ester to afford 21a and 21b respectively. Amide formation with the appropriate acid chloride as previously described yielded amides 23a-23j and 24. Subsequent Suzuki-Miyaura41 cross-coupling afforded intermediates 25a-25j and 27 which were chemoselectively hydrolyzed to yield final compounds 26a-26j and 28. Further, hydrolysis of the tosyl moieties in 26i and 26j, afforded 26k and 261 respectively (Scheme 4).

Scheme 4: Synthesis of meta-substituted amide derivatives of class II, II -A and boronic ester derivative 24 of class III. Commercially available 4-bromo-2-iodoaniline (29) was used as a starting material for the synthesis of compounds 33a and 33b of class III analogues. After installation of the amide chain by reaction with acid chloride as previously described, Mizoroki-Heck cross-coupling regioselectively afforded intermediate 31 due to the increased reactivity of iodide over bromide for the reaction.38 Suzuki-Miyaura41 cross coupling with substituted pinacol boronate followed by tert-butyl ester deprotection yielded compounds 33a and 33b (Scheme 5).

Scheme 5: Synthesis of 33a and 33b as amide derivatives of class III.

Further, to modify the side chain substitution pattern of the baccharin scaffold A ring to the 1,3,5 all meta-substituted pattern, 3-bromo-5-iodobenzoic acid (34) was used as the common starting material for the synthesis of amide and retroinverse amide or ester analogues. Conversion of 34 to 3-bromo-5- iodoaniline (35) was achieved by modified Curtius rearrangement, 43 followed by Boc deprotection. A reaction sequence of amide synthesis using acid chloride, followed by Pd-catalyzed cross-couplings in the order of Mizoroki-Heck reaction followed by Suzuki-Miyaura reaction afforded tert-butyl protected intermediates that were subsequently hydrolyzed to afford compounds 39a and 39b. Conversion of 34 to its acid chloride followed by esterification or amide formation using phenylethyl alcohol, or substituted primary amine, yielded the ester and amide intermediates (42, 41a-h) respectively. The reaction sequence of Mizoroki-Heck, Suzuki-Miyaura and tert-butyl ester hydrolysis was used to obtain compounds 49a-h and 50-52 of class IV and IV-A (Scheme 6).

Scheme 6: Synthesis of 1,3,5-meta-substituted derivatives (39a and 39b, 49a-h and 50-52) of class IV and IV-A. Ether analogues 58a and 58b were synthesized using 3-bromo-4-hydroxybenzoic acid (53) as the starting material which was reacted with benzyl bromide or 3-methoxy benzyl bromide to install the ether side chain. After activating the carboxylic acid to an acid chloride, a reaction sequence of amide formation followed by Mizoroki-Heck reaction and tert-butyl ester hydrolysis afforded final compounds (58a and 58b) of class IV (Scheme 7).

Scheme 7: Synthesis of 1,3,5-meta-substituted derivatives (58a and 58b) of class IV. Structure-activity relationship. Class I and I-A analogues: Consistent with the previous findings, baccharin exhibited an IC50 of 0.1 μΜ for AKR1C3 inhibition with 420-fold selectivity over AKR1C2. Removal of the dihydrocinnamoyloxy group in la (drupanin) resulted in complete abrogation of AKR1C3 inhibition activity and selectivity. Replacement of the dihydrocinnamoyloxy group (compounds 8b-h) resulted in low or sub-micromolar inhibition potency for AKR1C3, without any significant loss in selectivity. Introduction of an acetoxy group (8b) and a cyclohexylacetoxy group (8d), decreased AKR1C3 inhibitory activity and selectivity by four-fold. As compared to 1 an increase in the carbon spacer in 8c decreased AKR1C3 inhibitory activity and selectivity by two-fold and four-fold respectively. Excision of the ethyl linker to afford the benzoyloxy moiety (8f) reduced inhibition activity by three-fold and isoform selectivity to AKR1C3 by seven-fold. Replacement of the side chain ester phenyl moiety of 1 with a bulky napthyl (8e) or straight chain hexanoyloxy substituent (8h) exhibited similar inhibition profiles; decreasing the inhibition activity by three-fold with eight-fold loss of selectivity as compared to 1. Replacement of the phenethyl ring in 1 with a pyridine ring (8g) significantly reduced activity and selectivity. Comparison with the phenyl derivative (8f) indicates the pyridine ring is solely responsible, potentially due to its ability to ionize under the assay conditions, resulting in repulsive interactions in the enzyme active site. Interestingly, the corresponding amide derivatives (15a-e) were less active inhibitors than their bioisosteric counterparts (1, 8b-e). Activity ranges varied from three-fold reduction of AKR1C3 inhibitory activity (compare 1 to 15a and 8c to 15c) to eight-fold reduction (compare 8b to 15b) between ester and amide bond derivatives. Likewise, the amide derivatives, with the exception of 15a were also significantly more promiscuous between AKR1C isoforms with only moderate to minimal selectivity for the AKR1C3 isoform over the AKR1C2 variant. Fortuitously the amide derivative of baccharin (15a) retained potency and high selectivity, IC50 = 0.326 μΜ with 172-fold selectivity for AKR1C3 over the closely related AKR1C2 isozyme (Table 1).

Table 1. Inhibitory properties of class I analogues on AKR1C3 and AKR1C2.

Introduction of electron-withdrawing fluorine substituents on the B-ring at any position (8i-j) exhibited very similar inhibition profiles to 1 and only marginally decreased the fold-selectivity. When an electron- donating methoxy group is installed on the B-ring inhibition activity is equipotent with the parent scaffold across all substitution positions. However, a clear correlation between selectivity and substitution position is observed. When substitution occurs at the para (81) or ortho (8n) positions a twofold loss of selectivity is apparent. When substitution occurs at the meta position (8m) an inhibitor of equal selectivity to the parent compound is obtained (Table 2).

Table 2. Inhibitory properties of class I-A analogues on AKR1C3 and AKR1C2.

Class II and II-A analogues: The meta-substituted derivatives 19a, 26a and 26b showed enhanced AKR1C3 inhibitory activity. The meta-ester derivative (19a) represents the best combination of potent inhibitor (IC50 = 0.088 μΜ) with selectivity from all of the derivatives discussed thus far, with 261-fold selectivity for AKR1C3. The meta-amide derivative (26a) is the most potent AKR1C3 inhibitor identified among all the baccharin derivatives synthesized to date (IC50 = 0.066 μΜ), equipotent with the most active reported AKR1C3 enzyme inhibitors.44 Selectivity is diminished over the parent scaffold, but the compound still retains a 109-fold affinity for AKR1C3. Introduction of structural rigidity in the side chain amide via formation of a trans alkene (26b) decreased the inhibition activity for AKR1C3 (IC50 = 0.098 μΜ) as compared to 26a but resulted in increased selectivity by 1.5 fold. In comparison with the parent scaffold 26b retained equipotency with 1 but suffered a three-fold loss of selectivity. This data suggests that free rotation on this side chain is essential for high selectivity. Replacement of the prenyl chain with a 3-hydroymethylphenyl group (27) took a toll on both inhibition activity (5-fold reduction over 1) and selectivity (50-fold loss over to 1). Removal of the two methyls of the prenyl chain, to provide terminal alkene 19b, also diminished activity and selectivity suggesting that the methyls extend into an open pocket in the active site of AKR1C3 acting to confer selectivity and inhibition activity . Removal of the prenyl and ester side chains (17a) completely abrogated the bioactivity (Table 3).

Table 3. Inhibitory properties of class II analogues on AKR1C3 and AKR1C2.

Based on the enhanced potency of 26a the inventors next sought to investigate the effect of substituents on the B-ring of the parent scaffold. Such derivatives exhibited a range of activities from compounds more active than 1 (26c-h) to a reduction of approximately 1.5-fold in AKR1C3 inhibition potency (26i- 1). Introduction of fluorine displayed fairly similar potencies, comparable to 26a, with the meta substitution (26d) showing a slight advantage over ortho and para. However, the inhibition selectivity decreased by approximately 1.5-fold (26c-e). Interestingly, methoxy substition at the para positions (26f) increased isoform selectivity as compared to 26a and all substitution patterns conserved the inhibition activity (26f-26h). The inhibition profiles of tosyl (26i and 26j) and hydroxyl (26k and 261) substituted analogues were comparable to 1 with only a marginal decrease in activity, however the selectivity decreased by 5-10 fold (Table 4).

Table 4. Inhibitory properties of class II-A analogues on AKR1C3 and AKR1C2.

Class III analogues: Boronic acid bioisosteres of carboxylic acids may be expected to demonstrate increased binding affinity to their molecular targets on account of their ability to covalently interact with side chain amino acid residues in the binding pocket, as compared to hydrogen bonding interactions provided by their carboxylic acid counterparts.45 Bioisosteric replacement of the carboxylic acid of theparent scaffold with a pinacol boronate (7) or a boronic acid (7a) decreased AKR1C3 inhibition activity by 66- and 23-fold respectively compared to 1, with a concurrent 500-fold decrease in selectivity. Removal of the prenyl moiety (24) abrogated bioactivity in agreement with theprevious findings. Surprisingly, when the amide chain was placed ortho to the carboxylic acid group (33a) a 1.4-fold increase in activity was observed compared to 15a with comparable selectivity. Replacement of the prenyl moiety in 33a with a 3-hydroymethylphenyl moiety (33b) diminished activity and selectivity by five-fold and 12-fold respectively in comparison to 33a (Table 5).

Table 5. Inhibitory properties of class III analogues on AKR1C3 and AKR1C2.

Class IV and IV-A analogues: Arrangement of the side chains on the central ring in a 1,3,5 substitution pattern, greatly enhanced the selectivity for AKR1C3 inhibition over the homologus AKR1C1, 1C2 and 1C4 isoforms, as compared to 1. With the exception of 39b all compounds possessing this substitution pattern showed inhibitory potency in the low sub-micromolar range, with the majority exhibiting activity greater than 1 (39a and 39b, 49a-h) (Tables 6 and 7). The meta-amide 39a displayed inhibitory activity similar to 1 with a 1.5-fold increase in selectivity over the closest isoform AKR1C2, while the selectivity over other AKR isoforms was also increased. Consistent with previous observations, replacement of the prenyl moiety with 3-hydroymethylphenyl (39b) diminished activity and selectivity over 1C2 by 100-fold and 21-fold respectively. When the amide was reteroinverted (49a), the inventors gratifyingly observed an isoform selectivity >2857-fold over AKR1C2, an increase of seven-fold as compared to 1. Selectivity over the other isozymes AKR1C1 and AKR1C4 increased by 1.5 and 7-fold respectively when compared to 1. Moreover, 49a demonstrated an IC50 of 0.07 μΜ for AKR1C3, which is a 1.5-fold increase from 1. Replacement of the prenyl moiety with an allyl group (50) resulted in a seven-fold reduction in isoform selectivity and four-fold reduction in selectivity in agreement with prior data (19b). Although compound 50 did exhibit similar selectivity over AKR1C2 with a two-fold reduction in potency as compared to thehit scaffold. Replacement of the prenyl chain with a 3-hydroymethylphenyl moiety (51) again reduced AKR1C3 inhibitory activity (three-fold from 1) as well as selectivity (1.3-fold from 1), although to a lesser extent than 39b. The meta-ester analogue (52) decreased AKR1C3 inhibitory activity by 1.7-fold and selectivity over 1C2 by five-fold from its amide counterpart (49a), while still maintaining an increase in selectivity (1C2) of 1.25-fold from 1 and an equipotent inhibition activity for 1C3. The ether analogues (59a-59b) suffered great loss (18-46 fold) in inhibition selectivity over 1C2 and a decrease in inhibition activity (two - four-fold) when compared to 49a (Table 6).

Table 6. Inhibitory properties of class IV analogues on AKR1C1-AKR1C4.

AKR1C3 IC50 and fold selectivity over AKR1C2 highlighted in red. Substitutions on the B-ring were coupled with homologation of the amide chain in class IV-A analogues. Generally, all the substitutions were very well tolerated increasing the selectivity for AKR1C3 inhibition by three - seven-fold in comparison to 1 and maintaining the inhibition potency equivalent to or greater than 1 (49b-f). The 4- fluoro (49b) and 4-methoxy (49c) substitutions on the phenethyl side chain exhibited similar inhibition activity to 1, increasing the selectivity over 1C2 by three-fold. Reduction of the carbon spacer length, along with substitution with N,N-dimethyl (49h), methoxy (49d) or methyl (49g) groups at the 4-position on the benzyl side chain further increased the inhibitory activity as compared to 1. Compounds 49h and 49d were three-fold more selective than 1, whereas 49g exhibited the best combination of potency (IC50 = 0.071 μΜ) as well as selectivity (>2800, a seven-fold increase from 1). The 4-trifuoromethoxy benzyl containing analogue (49e) exhibited similar inhibition and selectivity profile as 49b. However, movement of the -OCF3 group to the meta position (49f) diminished inhibition activity by 1.3-fold and selectivity to AKR1C2 by 1.5-fold compared to 1 (Table 7).

Table 7. Inhibitory properties of class IV-A analogues on AKR1C1-AKR1C4.

Synergistic effect of AKR1C3 inhibition with daunorubicin in AML cell lines. The hit compound baccharin (1), m-amide analogue (26a) and 1,3,5 trisubstituted analogues 49a and 49g were selected for further studies on AML cell models as they represent a collection of the most active and selective AKR1C3 inhibitors. Consistent with the inventors' previous findings27 the inhibitors did not induce any cytotoxicity in AML cell lines up to concentrations as high as 100 uM (Figs. 48A-48D, 49A-49D, and 50A-50D). Low inhibitor concentrations of 0.1, 1 and 10 μΜ were chosen to evaluate the adjuvant effect with chemotherapeutic agents. Daunorubicin, an anthracycline used as front-line treatment for AML, experiences highest susceptibility to be metabolized by AKR1C3 among all of the anthracycline class of antitumor antibiotics.46 In order to evaluate if combination of AKR1C3 inhibitors with daunorubicin provides a synergistic effect, AKR1C3 inhibitors were dosed with daunorubicin in a fixed ratio of 100: 1 (inhibitondaunorubicin). Cell viability reduction in combination treatments of AKR1C3 inhibitors 1, 26a, 49a and 49g with daunorubicin was not detected to a level beyond what was observed with daunorubicin treatment alone (Fig. 33A-33D). The combination, when analyzed by the Chou-Talalay method, showed slight antagonistic, to merely an additive effect, in HL-60 cells with all the inhibitors tested (CI = 1.2 - 2.3), except 49a which was weakly synergistic (CI = 0.8) (Fig. 33C, Table 8).

FIGS. 33A-33D show the co-treatment of AKR1C3 inhibitors with daunorubicin in HL-60 cells. Percentage cell viability after 72 h co-treatment of daunorubicin with (33A) 1 (33B) 26a (33C) 49a (33D) 49g at indicated concentrations. In KGla cells which are daunorubicin-resistant, none of the combinations with AKR1C3 inhibitors were able to reduce the cell viability by more than 50% (Fig. 34A-34D) whereas only the concentrations of 0.1-10 μΜ AKR1C3 inhibitor with 0.01 μΜ daunorubicin were able to reduce the cell viability to >50 % in THP-1 cells which are derived from a pediatric patient with M5 sub-type AML (Fig. 35A-35D). FIGS. 34A-34D shows the co-treatment of AKR1C3 inhibitors with daunorubicin in KGla cells. Percentage cell viability after 72 h co-treatment of daunorubicin with (34A) 1 (34B) 26a (34C) 49a (34D) 49g at indicated concentrations. FIGS. 35A to 35D shows the co- treatment of AKR1C3 inhibitors with daunorubicin in THP-1 cells. Percentage cell viability after 72 h co-treatment of daunorubicin with (35A) 1 (35B) 26a (35C) 49a (35D) 49g at indicated concentrations.

Combination experiments as co-treatments in KGla (daunorubicin-resistant) and THP-1 cells demonstrated a weak synergistic effect with all tested inhibitors (CI = 0.2-0.8) with the exception of 1 which was additive (Table 8). Such discrepancies can be rationalized to a hydrolytic instability of 1.

Table 8. Quantification of drug interactions in AML cells after co-treatment with AKR1C3 inhibitors and daunorubicin.

Pre-treatment of AKR1C3 inhibitors for 24 h followed by daunorubicin exposure for a further 72 h enhanced cytotoxicity in HL-60 cells. A near complete cell viability reduction was seen in combinations of AKR1C3 inhibitor compounds with 0.1 μΜ daunorubicin (Fig. 5 A-D). When the effect was quantified, a weak to moderate drug synergism was noted (CI = 0.2 - 0.7) (Table 9).

FIGS. 36A to 36D shows the 24 h Pre-treatment of AKR1C3 inhibitors with daunorubicin in HL-60 cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of (36A) 1 (36B) 26a (36C) 49a (36D) 49g at indicated concentrations. The high AKR1C3 expressing KGla cells displayed a complete abrogation of cell viability at all inhibitor combinations with daunorubicin that reached as low as 0.1 μΜ inhibitor and 0.001 μΜ daunorubicin (Fig. 37A-37D). A very strong degree of synergistic drug effect with all inhibitors was seen (CI = >0.01), providing a chemotherapeutic dose reduction of > 100-fold (DRI >100) and reducing the combination IC50 to <0.01 μΜ, indicating complete reversal of duanorubcin-resistance (Table 9).

FIGS. 37A to 37D shows the 24 h Pre-treatment of AKR1C3 inhibitors with daunorubicin in KGla cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of (37 A) 1 (37B) 26a (37C) 49a (37D) 49g at indicated concentrations. A complete cell viability reduction was also noted in THP-1 cells at 0.01 and 0.1 μΜ daunorubicin combination with all AKR1C3 inhibitors tested and a cell viability reduction of >50% was seen at 0.001 μΜ daunorubicin combination as compared to no cell viability reduction at 0.001 μΜ daunorubicin alone (Fig. 38A-38D). A strong synergism was established in THP-1 cells (CI = 0.06 - 0.1) where the reduction in IC50 value of daunorubicin was greater than seven-fold. The more potent and selective compounds 49a and 49g provided a greater reduction (DRI = 16) in chemotherapeutic dosing as compared to 1 and 26a (DRI = 6.6 - 8.3) (Table 9). Such high degree of drug synergism can be attributed to the inhibition of AKR1C3 activity using compounds 1, 26a, 49a and 49g for 24 h prior to daunorubicin exposure in pre-treatment experiments as compared to the co- treatments where only an additive to moderate synergism was observed.

FIGS. 38A to 38D shows the 24 h Pre-treatment of AKR1C3 inhibitors with daunorubicin in THP-1 cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of (38A) 1 (38B) 26a (38C) 49a (38D) 49g at indicated concentrations.

Table 9. Quantification of drug interactions in AML cells after 24 h pre-treatment with AKR1C3 inhibitors followed by daunorubicin exposure.

Synergistic effect of AKR1C3 inhibition with cytarabine in AML cell lines. Further, the first line AML chemotherapeutic cytarabine (AraC) was combined with AKR1C3 inhibitors under a similar dosing regimen as previously described. Until now, no relationship has been established between the enzymatic activity of AKR1C3 and sensitivity of leukemic cells to AraC. The inventors hypothesized that inhibition of AKR1C3 enzymatic activity will drive the production of PGJ2 series prostanoids that will eventually activate pro-apoptotic signaling and will be instrumental in providing a synergistic drug effect with the chemotherapeutic AraC.Upon co-treatment of AKR1C3 inhibitors with AraC in HL-60 cells the trend of cell viability reduction closely matched to that of AraC alone (Fig. 39A-39D). Effects ranged from moderate synergism (1, 7) (CI = 0.5) to slight antagonism (4) (CI = 3.4) and addition (6) (CI = 1) (Table 10).

FIGS. 39A to 39D shows the Co-treatment of AKR1C3 inhibitors with AraC in HL-60 cells. Percentage cell viability after 72 h co-treatment of AraC with (39A) 1 (39B) 26a (39C) 49a (39D) 49g at indicated concentrations. Similarly, KGla and THP-1 cell lines displayed nearly identical dose inhibition profiles for all AKR1C3 inhibitors that were similar to AraC treatment alone (Fig. 40A-40D and Fig. 41 A-41D). Only an additive drug combination effect was noted that was consistent among all tested inhibitors (CI = 0.9 - 1.4) (Table 10). FIGS. 40A to 40D shows the co-treatment of AKR1C3 inhibitors with AraC in KGla cells. Percentage cell viability after 72 h co-treatment of AraC with (40 A) 1 (40B) 4 (40C) 6 (40D) 7 at indicated concentrations. FIGS. 41A to 41D shows the co-treatment of AKR1C3 inhibitors with AraC in THP-1 cells. Percentage cell viability after 72 h co-treatment of AraC with (41A) 1 (41B) 4 (41C) 6 (4 ID) 7 at indicated concentrations.

Table 10. Quantification of drug interactions in AML cells after co-treatment with AKR1C3 inhibitors and AraC.

The 24 h pre-treatment experiments with AKR1C3 inhibitors and AraC provided strong synergistic effects in HL-60 cells (Fig. 42A^t2D). Combination index values ranged from 0.02-0.09 that provided a dose reduction in AraC ranging from 10-33-fold (Table 11).

FIGS. 42A to 42D shows the 24 h Pre-treatment of AKR1C3 inhibitors with AraC in HL-60 cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of (42A) 1 (42B) 26a (42C) 49a (42D) 49g at indicated concentrations. Similar to the observations made with pre-treatment of daunorubicin, AKR1C3 inhibitor pre-treatments followed by AraC exposure, also abrogated the cell viability at all compound concentrations, displaying a very strong degree of synergistic drug effect with all inhibitors (CI = <0.01) in the high AKR1C3 expressing KGla cells. A chemotherapeutic DRI of >100-fold was noted that reduced the combination IC50 to <0.01 μΜ (Fig. 43A-43D and Table 11). FIGS. 43A to 43D shows the 24 h Pre-treatment of AKR1C3 inhibitors with AraC in KGla cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of (43 A) 1 (43B) 26a (43C) 49a (43D) 49g at indicated concentrations.

Similarly, a strong synergism was observed in THP-1 cells (CI = 0.05-0.07) where the reduction in IC50 value of AraC was greater than 13-fold (Fig. 44A- 4D and Table 11). FIGS. 44A to 44D shows the 24 h Pre-treatment of AKR1C3 inhibitors with AraC in THP-1 cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of (44A) 1 (44B) 26a (44C) 49a (44D) 49g at indicated concentrations.

Table 11. Quantification of drug interactions in AML cells after 24 h pre-treatment with AKR1C3 inhibitors followed by AraC exposure.

Synergistic effect of AKR1C3 inhibition in primary patient-derived T-ALL cells. For further evaluation of the adjuvant effects of AKR1C3 inhibitors, primary patient-derived T-ALL cells were chosen. The children's oncology group COG-317 cell line represents a cell line derived from samples of pediatric patients who relapsed after chemotherapy, whereas COG-329 cells were derived from samples of pediatric patients prior to chemotherapy treatment. Compound 49a, with the best combination of AKR1C3 inhibition activity and isoform selectivity, demonstrated a very strong synergistic drug effect in both COG-317 and COG-329 cell lines when co-treated with daunorubicin (DRI = 19.8-13.0 respectively) (Figs. 45 A, 45B and table insert). The DRI was greater in the relapsed T-ALL cells (COG- 317) which have been shown to overexpress the AKR1C3 target that imparts drug-resistant properties at relapse. The degree of drug synergism increased even further among pre-treatment experiments (DRI > 100) and a near complete abrogation of cell viability was noted in COG-317 cells (Fig. 45C, 45D and table insert). Both co-treatment and pre-treatments of 49a with AraC showed a very strong synergism in COG-317 cells (DRI > 100) (Fig. 45A, 45C and table insert). Among COG-329 cells the effect increased from DRI of 15.7 among co-treatments to >100 in pre-treatment experiments (Fig. 45B, 45D and table insert).

FIGS. 45A to 45D shows the synergistic effect of compound 49a with daunorubicin in primary T-ALL cells. Percentage cell viability after 72 h co-treatment of 49a and daunorubicin in (45A) COG-317 (45B) COG-329 cells. Percentage cell viability after 72 h exposure of daunorubicin with 24 h pre-treatment of 49a in (45C) COG-317 (45D) COG-329 cells. FIGS. 45E to 45G shows the treatment of COG T-ALL cells with 49a and chemotherapeutics. Percentage cell viability after 72 h treatment of AML cells with (45E) 49a (45F) daunorubicin and (46G) AraC at indicated concentration and time points.

FIGS. 46A to 46D shows the synergistic effect of compound 49a with AraC in primary T-ALL cells. Percentage cell viability after 72 h co-treatment of 49a and AraC in (A) COG-317 (B) COG-329 cells. Percentage cell viability after 72 h exposure of AraC with 24 h pre-treatment of 49a in (C) COG-317 (D) COG-329 cells. FIGS. 46E and 46F shows the combination treatment of BMMNC cells with 49a and chemotherapeutics. Percentage cell viability of BMMNC cells after pre-treatment with 49a followed by 72 h incubation with (46E) AraC and (46F) daunorubicin at indicated concentrations. Synergistic effect of AKR1C3 inhibition in primary bone marrow mononuclear cells (BMMNC). In order to evaluate the selective chemotherapeutic potentiation of AKR1C3 inhibitor 49a towards leukemic cells, 24 h pre-treatment experiments with 49a followed by incubation with AraC and daunorubicin were performed in primary bone marrow mononuclear cells. No chemotherapeutic potentiation was noted with both AraC and daunorubicin treatments (FIGS. 46E and 46F).

Other groups have studied different classes of inhibitors for AKR1C3 in order to develop new therapeutics for the treatment of CRPC based on NSAID scaffolds. 23, 29-31, 47-53 Although inhibitors with nanomolar potency and high selectivity to AKR1C3 have been identified from these studies, the discovery of new compounds for preclinical development is still required. Among these compounds, baccharin, a natural component extracted from Brazilian propolis, displays a high potency and inhibitory selectivity against AKR1C3.23 This discovery has made baccharin a promising hit to develop a new series of potent and specific inhibitors against AKR1C3.

In this study, the inhibitory potency and selectivity of several baccharin analogs against AKR1C3 were investigated and compared to unmodified baccharin (1). Compound 26a showed the most potent inhibition (IC50: 66 nM) whereas compound 49a displayed the highest selectivity for AKR1C3 over AKR1C2 (IC50 ratio: >2857). Analysis of crystal structures of AKR1C3.NADP+- inhibitor complexes have revealed that the ligand binding site can be dissected into five subsites: oxyanion site (consisting of catalytic residues Tyr55, Hisl l7 and cofactor NADP+), the steroid channel for the binding of steroid ligands, and three sub-pockets (SPs: SP1, SP2 and SP3 to accommodate other ligands).47, 54 In the AKR1C3.NADP+. Baccharin complex model (Fig. 2.4), 23 the carboxylate group on cinnamic acid was predicted to be bound in the SP1 pocket and could form hydrogen bonds with the side chain of Serl l8, which contributes to strong binding affinity for 1. In addition, several polar amino acids (e.g. Ser308 and Tyr319) also reside in the SP1 pocket of AKR1C3 which provide hydroxyl groups that can interact with the polar groups of these inhibitors. As such, these polar interactions also increase the selectivity of baccharin for AKR1C3 over the other AKR1C isoforms where the amino acids in the corresponding positions are Phel l8, Leu308 and Phe319 in the SP1 pocket.30, 54 The docked model predicted that the benzyl moiety of the 4-dihydrocinnamoyloxy group was located in the SP3 pocket and could form hydrophobic interactions with the side chain of Gln222 or Phe306 to provide the high binding affinity .23 In addition, recent studies have shown that polar substitutions (e.g. hydroxyl and carboxylate group) on the phenyl ring of cinnamic acid or the phenyl ring of the 4-dihydroxycinnamoyloxy group decreased the inhibition for AKR1C3 23, 55, 56. For example, the displacement of 4-dihydrocinnamoyloxy group by a hydroxyl group to form drupanin (la) resulted in a loss of inhibitory potency (IC50: 15 μΜ) and only a 7-fold selectivity for AKR1C3 versus AKR1C2. Increase or decrease of carbon spacer along with a replacement of the B-ring in class I analogues exhibited low or sub-micromolar inhibition activities (8b- 8h) but still exhibited >50-fold isoform selectivity. In order to impart hydrolytic stability to the compounds, replacement of the ester functional group with an amide was performed. The corresponding amide bioisosteres displayed diminished activity and selectivity (15a-15e) suggesting that the rigidity of the side chain amide is not beneficial at the para-position (class I analogues). The B-ring substitutions on the dihydrocinnamoyloxy moiety were very well tolerated and only a marginal reduction of activity and selectivity was observed (8i-8n, class I-A analogues).

When the substitution pattern of the dihydrocinnamoyloxy side chain was changed to the meta-position (class II analogues 19a and 26a and 26b) the inhibitory potency increased in comparison to 1. The presence of either a carbonyl or carboxylate group is required to anchor many ligands to the oxyanion site, because it can form a strong hydrogen-bond with Tyr55 and Hisl 17 and bring the ligands into close proximity of the nicotinamide head group of the cofactor.54 Based on the model of baccharin-docked into the AKR1C3-NADP+ complex structure, the carbonyl group on the 4-dihydrocinnamoyloxy group of baccharin was found to be close to the oxyanion site and could form a H-bond interaction with Tyr55 and Hisl 17, which could contribute to the high inhibitory activity of baccharin. Thus, it seems plausible that in class II analogues the carbonyl group was now positioned in close proximity to the oxyanion site imparting enhanced potency. The presence of a side chain amide increased activity even further (compound 26a) along with exhibiting a good tolerability of B-ring substituents (class II-A analogues). Further modifying the side chain substitution pattern did not increase activity or selectivity (33a-33b). Contrary to expectation, the boronic acid analogue (7a) lost inhibition potency by more than ten-fold and abrogated isoform-selectivity (class III analogues). Similar to class II analogues, the retroinverted amide group of compounds of class IV (49a-f, 51 and 52) could maintain a stronger Hydrogen bond interaction in comparison to the straight amide analogues (39a and 39b) in the oxyanion site to provide an even superior inhibitory potency. In addition, substituting the side chains in a 1,3,5 arrangement at the A-ring places the prenyl ring in close proximity to the hydrophobic amino acid residues of the SP2 subpocket that imparts exquisite selectivity (FIG. 47). FIG. 47 shows a Baccharin SAR map.

FIGS. 50A to 50D shows the treatment of THP-1 cells with AKR1C3 inhibitors. Percentage cell viability after 72 h treatment of THP-1 cells with (50A) 1 (50B) 26a (50C) 49a (50D) 49g at indicated concentrations and time points.

In conclusion, the current study revealed a detailed SAR map of baccharin derivatives for inhibition of AKR1C3 and identified new classes of inhibitors (FIG. 47). The 1,3,5 meta-substituted retro-inversion amides of class IV and IV-A are disclosed as the most selective inhibitors of AKR1C3 across all known inhibitor classes reported thus far. A first of their kind to exhibit >2857-fold selectivity for AKR1C3 inhibition with a retention of inhibitory potency in the nanomolar range. These agents carry a potential to be further developed into clinical drug candidates and span applicability across a diverse variety of malignancies that are AKR1C3 dependent.

AKR1C3 inhibitors derived from modification of a natural product have enhanced biological stability and exhibit extremely selective and potent activity. Proof-of-concept that AKR1C3 inhibitors derived from baccharin have a synergistic effect sensitizing AML and T-ALL cells to the chemotherapeutic effects of daunorubicin and AraC is demonstrated. Treatment of the non-toxic AKR1C3 inhibitors in in vitro models of acute myeloid leukemia representing various French-American-British (FAB) sub-types of AML (MO, M3 and M5), along with co-administration of a range of clinical chemotherapeutics, results in a synergistic drug action, potentiating cytotoxicity and reducing the IC50 value. This is contrary to recent reports detailing selective AKR1C3 inhibitors do not perform an adjuvant role as compared to pan- AKR1C isoform inhibitors.57 This observation is further extended to the primary patient-derived T-ALL cells where a very strong potentiation of the effects of daunorubicin and AraC was established.

These results demonstrate that a strategy developing small molecule AKR1C3 inhibitors may yield powerful adjuvant agents for the synergistic treatment of leukemia with chemotherapeutic drugs, especially since favorable toxicity and pharmacokinetic properties can exist within the baccharin structure. In contrast to previously reported studies, potent and selective inhibition of AKR1C3 results in potentiation of the clinical chemotherapeutics: etoposide, daunorubicin and AraC in multiple AML cell lines. The identified highly potent and selective derivatives represent valuable lead compounds to understand the structural features required for AKR1C3 inhibitory activity and selectivity, and how these properties interrelate to further theunderstanding of the role which AKR1C3 plays to enable potentiation of chemotherapeutic effect within AML pathophysiology. Further development of the inhibitors describe herein represents a significant drug discovery opportunity for the identification of potent adjuvants to enhance the therapeutic index of chemotherapeutics, in the hope of availing this treatment regime to pediatric and geriatric AML patients.

Enzyme Inhibition Assay: A detailed account of the chemistry procedures and characterizations (1H, 13C NMR, and HRMS) was performed. The enzyme inhibition screen for all compounds was perfbmed in collaboration with the Penning lab at the University of Pennsylvania. (S)-(+)- 1,2,3, 4-tetrahydro-l- naphthol (S-tetralol) was purchased from Sigma-Aldrich (St. Louis, MO). Nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+) were purchased from Roche Diagnostics (Indianapolis, IN). Homogeneous recombinant enzymes AKR1C3 and AKR1C2 were prepared and purified as previously described.28 The specific activities of AKR1C3 and AKR1C2 for the oxidation of S-tetralol are 2.0 and 1.5 μιηοΐ min-1 mg-1, respectively.

Assay of enzyme activity: The dehydrogenase activities of AKR1C3 and AKR1C2 were determined by measuring the UV absorption of NADH formation at 340 nm using Beckman DU640 spectrophotometer. A typical assay solution contained 100 mM potassium phosphate pH 7.0, 2.3 mM NAD+, 3.0 mM (S)- (+)-l,2,3,4-tetrahydro-l-naphthol (S-tetralol), 4% acetonitrile (v/v). The mixtures were incubated at 37 °C for 3 min followed by adding a serial dilution of AKR1C3 or AKR1C2 solution to a final volume of 1 mL to initiate the reaction. After continuously monitoring for 5 min, the increase in UV absorption using different concentrations of enzyme were recorded to calculate the initial velocity and determine enzyme specific activity.

IC50 value determination: The inhibitory potency for each compound was represented by IC50 value and measured as described before 29-31. The IC50 value of baccharin and baccharin analogs was determined by measuring their inhibition on the NADP+ dependent oxidation of S-tetralol catalyzed by AKR1C3 or AKR1C2. The concentration of S-tetralol used in this assay for AKR1C3 and AKR1C2 was 165 μΜ and 15 μΜ respectively, which was equal to the Km value for each enzyme isoform in order to make a direct comparison of IC50 values. The IC50 value of each compound was acquired from a single experiment with each inhibitor concentration run in quadruplicate and directly calculated by fitting the inhibition data to an equation [y = (range) / [1 + (I/IC50)S] + background] using Grafit 5.0 software. In this equation, "range" is the fitted uninhibited value minus the "background", and "S" is a slope factor. "I" is the concentration of inhibitor. The equation assumes that y falls with increasing "I".

Adjuvant assay: HL-60 (ATCC® CCL-240TM), KGla (ATCC® CCL-246.1TM) and THP-1 (ATCC® TIB-202™) cells were procured from ATCC. Isocove's Modified Dulbecco's Media (IMDM) supplemented with 20% fetal bovine serum (FBS) and penicillin/streptomycin (1%) was used to culture HL-60 and KGla cells whereas THP-1 cells were cultured using Roswell Park Memorial Institute (RPMI)-1640 medium, supplemented with 20% fetal bovine serum (FBS), 0.05 mM 2-mercaptoethanol and penicillin/streptomycin (1%). Cells were maintained at a density of 0.1-1 x 106 cells/mL under 5% C02 at 37 oC. To screen the test compounds, cells were seeded at a density of 0.1 x 106 cells/mL in 96- well plates containing 100 μL cell suspension per well. Stock solutions of the test compounds, etoposide, daunorubicin and cytarabine (AraC) were prepared in DMSO. Cells were treated at the indicated concentrations of test compounds with or without the chemotherapeutic agents, limiting the final DMSO concentration to less than 1%. After incubation at 37 OC, 5% C02 for 24, 48, 72 or 96 h, 20 μL of MTS reagent (CellTiter 96® AQueous One Solution Reagent) was added to each well and incubated at the above mentioned conditions for 2-3 h. Plates were read at OD 490 nm on a plate reader and the viability of cells were plotted as percentage of controls.

Quantification of the degree of synergism: To quantify the degree of synergism, the results of the co- treatment and pre-treatment experiments were analyzed by CompuSyn software (Paramus, NJ) based on the median effect principle or 'Chou-Talalay' method.32 The method is based on the median-effect equation that encompasses the Michaelis-Menten, Hill, Henderson-Hasselbach, and Scatchard equations to provide combination and dose reduction indices.33 The combination index (CI) and dose reduction index (DRI) values were calculated at a constant ratio of chemotherapeutic to AKR1C3 inhibitor at 50% cytotoxic effect (Fa = 0.5). CompuSyn software was used to generate the CI and DRI values. CK1, synergism; CI> 1.1, antagonism; CI=1.1, additive.34

Western blotting: HL-60 and KGla cells were treated with compound (4) over a period of 48 and 72 h at indicated concentrations after which they were harvested and pelleted. The whole cell lysates were prepared in radioimmunoprecipitation assay RIPA buffer containing protease and phosphatase inhibitors (1 mM PMSF, 38 μg/mL aprotinin, 2.5 mM Na3V04). Samples were incubated on ice for 30 min after which they were sonicated, centrifuged (16000 x g) and supernatant collected. Protein concentration in each sample was estimated following bicinchoninic acid BCA assay protocol by comparing with the BSA standards (PierceTM BCA protein kit). Protein samples (40 μg ) containing loading dye (7 μΐ.) were loaded onto 12% SDS polyacrylamide gel and electrophoresed (80 V, 2 hr). Transferred onto a PVDF membrane overnight (25 V, 4 oC). The membrane was blocked with 5 % non-fat milk (1 h) and probed with human anti-AKRlC3 mouse monoclonal antibody (1:500, R&D Systems, MAB7678) and corresponding horseradish peroxidase (HRP) conjugated anti-mouse secondary antibody followed by immunodetection using VersaDocTM (MP 5000). Membrane was stripped and re-probed for β-actin (1 :5000, Sigma-Aldrich, A5441). Quantity One® software was used to analyze the band intensities and fold change in AKR1C3 enzyme expression was determined based on β-actin controls.

General Chemistry Procedures.

All reactions were carried out in oven- or flame-dried glassware under positive nitrogen pressure unless otherwise noted. Reaction progress was monitored by thin-layer chromatography (TLC) carried out on silica gel plates (2.5 cm x 7.5 cm, 200 μιη thick, 60 F254) and visualized by using UV (254 nm) or by potassium permanganate and/or phosphomolybdic acid solution as indictor. Flash column chromatography was performed with silica gel (40-63 μιη, 60 A) using the mobile phase indicated or on a Teledyne Isco (CombiFlash Rf 200 UV/Vis). Commercial grade solvents and reagents and solvents were purchased from Fisher Scientific (Houston, TX), Sigma Aldrich (Milwaukee, WI) or for Prenyl boronic acid pinacol ester, Santa Cruz Biotechnology (Dallas, TX) and were used without further purification except as indicated. Anhydrous solvents were purchased from Across Organics and stored under and atmosphere of dry nitrogen over molecular sieves.

1H, 13C, COSY, HMQC and DEPT NMR spectra were recorded in the indicated solvent on a Bruker 400 MHz Advance III HD spectrometer at 400 and 100 MHz for 1H and 13C respectively with TMS as an internal standard. Multiplicities are indicated by s (single), d (doublet), dd (doublet of doublets), t (triplet), q (quartet), m (multiplet), br (broad). Chemical shifts (δ) are reported in parts per million (ppm), and coupling constants (J), in hertz. High resolution mass spectroscopy was performed on a LC/MS IT- TOF (Shimadzu) using an ESI source conducted at the University of Texas at Arlington, Shimadzu Center for Advanced Analytical Chemistry. High-pressure liquid chromatography was performed on a Dynamax HPLC system installed with a Varian pro star UV detector with a Phenomenex® Luna (CI 8 100 A, 250x4.6 mm) column. All samples were assessed to be of >96% purity. General procedure A: Synthesis of ester intermediates:

To a solution of 4-iodo-2-(3-methylbut-2-en-l-yl)phenol (7) (1 equiv) in DCM (5 mL) was added DMAP (0.1 equiv) followed by addition of substituted acid chloride and NEt3 (1.5 equiv). The mixture was stirred overnight at RT. Saturated NaHC03 was added and the layers seperated. The organic layer was washed with H20, dried (Na2S04), filtered and concentrated. The crude product was purified by column chromatography using Hexane/EtOAc gradient (10: 1, 4: 1, 2: 1) and solvent evaporated in vacuo to provide pure esterified compounds.

General procedure B: t-Bu ester hydrolysis:

To a solution of substituted tert-butyl intermediates in toluene was added chromatography grade silica gel and the mixture was refluxed with vigorous agitation overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over celite pad using 10% methanol in DCM as the solvent. The crude product was purified by column chromatography using DCM/MeOH gradient (20: 1, 10: 1) and solvent evaporated in vacuo to provide the final componds.

4-iodo-2-(3-methylbut-2-en-l-yl)phenol (3): To a solution of p-iodophenol (2 g, 9.08 mmol) in toluene (20 ml) was added NaH (60% disopersion in mineral oil, 540 mg, 13.62 mmol) when the effervescence ceased 3,3-dimethylallyl bromide (1.1 ml, 9.5 mmol) was added and the reaction was stirred at room temperature overnight. The reaction mixture was acidified to pH 1 with AcOH, washed with H20, extracted with DCM, dried ( a2S04), filtered and concentrated. Purified by column chromatography (5- 10% Et20:hexane) and solvent evaporated in vacuo to provide the title compound as a yellow oil (1.43 g, 4.96 mmol, 55%).

Rf: 0.5 (Hexane:EtOAc = 4: 1). 1H NMR (400 MHz; CDC13): δ 1.8 (6H, d, J = 8.0 Hz, CH3), 3.33 (2H, d, J = 6.88 Hz, CH2), 5.31 (1H, t, J = 6.6 Hz, CH), 5.46 (1H, s, -OH), 6.59 (1H, d, J = 8.2 Hz, Ar-H), 7.41 (2H, s, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.8, 25.8, 29.3, 82.7, 117.9, 120.69, 129.7, 135.4, 136.1. 138.3, 154.2.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl-3-phenylpropanoate (5a): Title compound was obtained following genral procedure A using 3-phenyl propionyl chloride (495 mg, 2.93 mmol) as a white solid (490 mg, 1.16 mmol, 60%).

1H NMR (400 MHz; CDC13): δ 1.66 (3H, s, CH3), δ 1.76 (3H, s, CH3), δ 2.91 (2H, t, J = 7.5 Hz, CH2) δ 3.09 (4H, t, J = 6.0 Hz, CH2CH2), δ 5.16 (1H, t, J = 7.1 Hz, CH), δ 6.69 (1H, d, J = 8.3 Hz, ArCH), δ 7.21-7.36 (6H, m, ArCH), δ 7.53 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 17.76, 25.85, 28.30, 30.24, 30.93, 35.68, 36.38, 90.49, 120.70, 124.40, 126.68, 128.44, 128.78, 133.86, 135.94, 136.32, 138.80, 140.03, 148.64, 170.95

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl acetate (5b): Title compound was obtained following genral procedure A using acetyl chloride (0.122 ml, 1.7 mmol) ) as a white solid (350 mg, 1.06 mmol, 92%).

1H NMR (400 MHz; CDC13): δ 1.70 (3H, s, CH3), δ 1.76 (3H, s, CH3), δ 2.31 (3H, s, OCH3), δ 3.19 (2H, d, J = 7.1 Hz, CH2), δ 5.19 (1H, t, J = 7.1 Hz, CH), δ 6.79 (1H, d, J = 8.0 Hz, ArCH), δ 7.55 (2H, d, J = 9.4 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 18.6, 20.9, 25.8, 28.4, 90.5, 120.6, 123.8, 124.3, 133.8, 135.9, 139.0, 148.8, 168.4

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl-4-phenylbutanoate (5c): Title compound was obtained following genral procedure A using 4-phenyl butanoyl chloride (190 mg, 1.1 mmol) as a yellow oil (591 mg, 1.3 mmol, 85%).

1H NMR (400 MHz; CDC13): δ 1.67 (3H, s, CH3), 1.73 (3H, s, CH3), 2.05 - 2.14 (2H, m, CH2), 2.59 (2H, t, J = 7.5 Hz, CH2), 2.77 (2H, t, J = 7.6 Hz, CH2), 3.18 (2H, d, J = 7.1 Hz, CH2), 5.18 (1H, t, J = 7.1 Hz, CH), 6.76 (1H, d, J = 7.9 Hz, Ar-H), 7.22 - 7.25 (3H, m, Ar-H), 7.31 - 7.35 (2H, m, Ar-H), 7.52 - 7.54 (2H, m, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 26.4, 28.4, 33.4, 35.0, 90.4, 120.6, 124.2,125.2, 126.1, 128.2, 128.4, 129.0, 134.0, 135.9, 136.1, 138.8, 141.0, 148.7, 171.5.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 2-cyclohexylacetate (5d): Title compound was obtained following genral procedure A using cyclohexylacetyl chloride (240 mg, 1.5 mmol) as a yellow oil (390 mg, 0.9 mmol, 99%).

1H NMR (400 MHz; CDC13): δ 0.97-1.36 (7H, m, cyc-H), 1.69 (3H, s, CH3), δ 1.74 (3H, s, CH3), 1.81- 1.95 (4H, m, cyc-H), 2.47 (2H, d, J = 7 Hz, CH2), 3.24 (2H, d, J = 7.1 Hz, CH2), 5.23 (1H, t, J = 7.1 Hz, CH), 6.77 (1H, d J = 8.2 Hz, Ar-H), 7.51 - 7.54 (2H, m, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 25.9, 26.0, 28.3, 33.0, 34.9, 41.9, 90.3, 120.7, 124.3, 134.0, 135.8, 136.1, 138.7, 148.8, 171.1.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 2-(naphthalen-l-yl)acetate (5e): Title compound was obtained following genral procedure A using naphthylacetyl chloride (210 mg, 1.1 mmol) as a yellow oil (256 mg, 0.6 mmol, 78%).

Rf: 0.84 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (3H, s, CH3), 1.68 (3H, s, CH3), 2.92 (2H, d, J = 7.2 Hz, CH2), 4.33 (2H, s, CH2), 4.98 (1H, t, J = 7.2 Hz, CH), 6.73 (1H, d, J = 11.3 Hz, Ar-H), 7.35 - 7.60 (6H, m, Ar-H), 7.83 - 7.92 (2H, m, Ar-H), 8.12 (1H, d, J = 11.7 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 28.1, 39.3, 90.9, 120.5, 123.6, 124.1, 125.5, 126.0, 126.6, 128.3, 128.5, 128.9, 129.7, 132.0, 133.8, 133.9, 135.8, 136.2, 138.7, 148.7, 169.6.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl benzoate (5f): Title compound was obtained following genral procedure A using benzoyl chloride as a yellow oil (270 mg, 0.6 mmol, 71%).

Rf: 0.71 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.56 (3H, s, CH3), 1.69 (3H, s, CH3), 3.25 (2H, d, J = 7.2 Hz, CH2), 5.20 (1H, t, J = 7.2 Hz, CH), 6.92 (1H, d, J = 8.0 Hz, ArCH), 7.52 - 7.69 (6H, m, ArCH), 8.21 (1H, d, J = 8.2 Hz, ArCH).

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl pyridine-4-carboxylate (5g): Title compound was obtained following genral procedure A using THF (7 mL) and isonicotinic acid chloride (425 mg, 3 mmol) as a brown oil (650 mg, 1.6 mmol, 73 %).

1H NMR (400 MHz; CDC13): δ 1.53 (3H, s, CH3), 1.64 (3H, s, CH3), 3.22 (2H, d, J = 6.6 Hz, CH2), 5.18 (1H, t, J = 6.5 Hz, CH), 6.88 (1H, d, J = 8.3 Hz, Ar-H), 7.55 (1H, d, J = 8.4 Hz, Ar-H), 7.59 (1H, s, Ar-H), 7.96 (2H, d, J = 4.0 Hz, Ar-H), 8.84 (2H, d, J = 3.4 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.8, 25.6, 28.8, 67.9, 65.8, 91.1, 120.5, 123.1, 124.1, 134.0, 136.0, 136.2, 136.3, 139.1, 148.6, 150.8, 163.2.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl hexanoate (5h): Title compound was obtained following general procedure A using hexanoyl chloride (135 mg, 1.0 mmol) as a yellow oil.

1H NMR (400 MHz; CDC13): δ 1.36 - 1.43 (7H, m, CH3 and CH2), 1.50 - 1.62 (2H, m, CH2), 1.69 (3H, s, CH3), 1.76 (3H, s, CH3), 2.57 (2H, d, J = 7.4 Hz, CH2), 3.18 (2H, d, J = 7.0 Hz, CH2), 5.19 (1H, t, J = 7.2 Hz, CH), 6.77 (1H, d, J = 8.3 Hz, ArCH), 7.52 - 7.54 (2H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 13.9, 22.3, 23.5, 24.6, 28.3, 31.3, 3.1, 90.3, 120.7, 124.2, 133.9, 135.9, 136.1, 138.7, 148.8, 171.8

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 3-(4-fluorophenyl)propanoate (5i): Title compound was obtained following genral procedure A using 3-(2-fluorophenyl)propanoyl chloride (260 mg, 1.4 mmol) as a yellow oil (280 mg, 0.63 mmol, 65 %).

Rf: 0.69 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.66 (3H, s, CH3), 1.75 (3H, s, CH3), 2.89 (2H, t, J = 7.5 Hz, CH2), 3.06 (4H, t, J = 7.2 Hz, CH2), 5.14 (1H, t, J = 7.2 Hz, CH), 6.69 (1H, d, J = 8.6 Hz, ArCH), 7.02 (2H, d, J = 8.7 Hz, ArCH), 7.22-7.26 (2H, m, ArCH), 7.50 - 7.53 (2H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 28.2, 30.0, 35.8, 90.6, 115.2, 115.5, 120.5, 124.2, 129.8, 135.9, 138.8, 138.9, 148.6, 160.4, 162.8, 170.8.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 3-(3-fluorophenyl)propanoate (5j): Title compound was obtained following genral procedure A using 3-(3-fluorophenyl)propanoyl chloride (260 mg, 1.4 mmol) as a yellow oil (430 mg, 1 mmol, 99 %).

1H NMR (400 MHz; CDC13): δ 1.66 (3H, s, CH3), 1.75 (3H, s, CH3), 2.90 (2H, t, J = 7.7 Hz, CH2), 3.0 (4H, t, J = 7.4 Hz, CH2), 5.15 (1H, t, J = 7.2 Hz, CH), 6.70 (1H, d, J = 7.6 Hz, ArCH), 6.92 - 7.0 (2H, m, ArCH), 7.05 (1H, d, J = 7.6 Hz, ArCH), 7.27 - 7.32 (1H, m, ArCH), 7.51 - 7.53 (2H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 28.2, 30.5, 35.3, 90.6, 115.2, 115.4, 120.5, 124.1, 130.0, 134.0, 135.0, 138.8, 142.4, 148.6, 160.4, 161.7, 170.7.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 3-(2-fluorophenyl)propanoate (5k): Title compound was obtained following genral procedure A using 3-(2-fluorophenyl)propanoyl chloride (260 mg, 1.4 mmol) as a yellow oil (430 mg, 1 mmol, 99 %).

1H NMR (400 MHz; CDC13): δ 1.70 (3H, s, CH3), 1.79 (3H, s, CH3), 2.94 (2H, t, J = 7.9 Hz, CH2), 3.08 - 3.14 (4H, m, CH2), 5.19 (1H, t, J = 7.2 Hz, CH), 6.74 (1H, d, J = 8.3 Hz, ArCH), 6.81 - 6.91 (3H, m, ArCH), 7.28 (1H, t, J = 7.8 Hz, ArCH), 7.53 - 7.57 (2H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.8, 28.3, 30.9, 35.7, 90.6, 111.8, 114.2, 120.7, 124.2, 129.6, 133.9, 136.0, 136.2, 138.8, 141.5, 148.7, 159.8, 170.9.

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 3-(4-methoxyphenyl)propanoate (51): Title compound was obtained following genral procedure A using 3-(4-methoxyphenyl)propanoyl chloride (200 mg, 1 mmol) as a yellow oil (420 mg, 0.9 mmol, 93 %). Rf: 0.75 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.69 (3H, s, CH3), 1.78 (3H, s, CH3), 2.90 (2H, t, J = 7.5 Hz, CH2), 3.03 - 3.11 (4H, m, CH2), 3.82 (3H, s, CH3), 5.18 (1H, t, J = 7.2 Hz, CH), 6.72 (1H, d, J = 8.3 Hz, ArCH), 6.90 (2H, d, J = 8.6 Hz, ArCH), 7.22 (2H, d, J = 8.6 Hz, ArCH), 7.52 - 7.56 (2H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.8, 28.2, 30.1, 36.0, 55.2, 90.6, 114.0, 120.7, 124.3, 129.3, 132.0, 133.9, 135.9, 136.2, 138.7, 148.7, 158.2, 171.0

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 3-(3-methoxyphenyl)propanoate (5m): Title compound was obtained following genral procedure A using 3-(3-methoxyphenyl)propanoyl chloride (300 mg, 1.5 mmol) as a yellow oil (280 mg, 0.62 mmol, 62 %).

Rf: 0.71 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.70 (3H, s, CH3), 1.79 (3H, s, CH3), 2.94 (2H, t, J = 7.5 Hz, CH2), 3.00 - 3.14 (4H, m, CH2), 3.84 (3H, s, CH3), 5.20 (1H, t, J = 7.2 Hz, CH), 6.74 (1H, d, J = 8.3 Hz, ArCH), 6.81 - 6.91 (3H, m, ArCH), 7.28 (1H, d, J = 8.0 Hz, ArCH), 7.53 - 7.57 (2H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.8, 28.3, 30.9, 35.7, 55.1, 90.6, 111.8, 114.2, 120.7, 124.2, 129.6, 133.9, 136.0, 136.2, 138.8, 141.5, 148.7, 159.8, 170.9

4-iodo-2-(3-methylbut-2-en-l-yl)phenyl 3-(2-methoxyphenyl)propanoate (5n): Title compound was obtained following genral procedure A using 3-(2-methoxyphenyl)propanoyl chloride (300 mg, 1.5 mmol) as a yellow oil (320 mg, 0.71 mmol, 71%).

1H NMR (400 MHz; CDC13): δ 1.73 (3H, s, CH3), 1.80 (3H, s, CH3), 2.94 (2H, t, J = 7.5 Hz, CH2), 3.11 - 3.18 (4H, m, CH2), 3.90 (3H, s, CH3), 5.22 (1H, t, J = 7.2 Hz, CH), 6.76 (1H, d, J = 8.3 Hz, ArCH), 6.92 - 7.00 (3H, m, ArCH), 7.29 - 7.31 (1H, m, ArCH), 7.54 - 7.58 (2H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.8, 26.2, 28.4, 34.1 55.2, 90.4, 110.3, 120.5, 120.8, 124.4, 127.9, 128.2, 133.8, 135.9, 136.2, 138.8, 148.9, 157.5, 171.4

tert-butyl(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-[(3-phenylpropanoyl)oxy]phenyl]prop-2-enoate (6a): To a solution of 5a (490 mg, 1.16 mmol) in anhydrous toluene (7 ml) was added PPh3 (46 mg, 0.175 mmol), Pd(OAc)2 (47 mg, 0.09 mmol) and NEt3 (0.245 ml, 1.75 mmol) the mixture was sitirred and t-Bu acrylate (0.275 ml, 1.75 mmol) was added to the flask which was refluxed overnight. The reaction mixture was washed with a saturated solution of NH4C1, water and extracted over DCM, dried over Na2S04 and filtered. Purified with silica gel flash chromatography using eluent system as Hexane:EtOAc = 60: 1, 30: 1, 20: 1 and solvent evaporated in vacuo to provide the title compound (280 mg, 0.66 mmol, 57%).

Rf : 0.6 (Hexane:EtOAc = 4: 1). 1H NMR (400 MHz, CDC13): δ 1.55 (9H, s, C02t-Bu), 1.69 (3H, s, CH3), 1.76 (3H, s, CH3), 2.93 (2H, t, J = 7.4 Hz, CH2), 3.10 (2H, t, J = 7.6 Hz, CH2), 3.16 (2H, d, J = 7 Hz, CH2), 5.20 (1H, t, J = 7 Hz, CH), 6.31 (1H, d, J = 15.9 Hz, CH), 6.96 (1H, d, J = 8.7 Hz, ArCH) 7.24-7.36 (7H, m, ArCH) 7.55(1H, d, J = 16 Hz, CH). 13C NMR (100 MHz, CDC13): δ 17.8, 25.7, 28.2, 28.5, 29.7, 30.9, 35.8, 80.5, 120.0, 120.35, 121.0, 121.9, 122.6, 126.5, 128.3, 128.6, 129.0, 129.7, 132.6, 133.7, 134.0, 139.9, 142.3, 142.8, 150.0, 166.2, 171.0. M/Z ESI: 443.2 [M+Na]+ (100%), 444.3(35%)

tert-butyl (2E)-3-[4-(acetyloxy)-3-(3-methylbut-2-en-l-yl)phenyl]prop-2-enoate (6b): To a solution of 5b (350 mg, 1.0 mmol) in dry toluene (6.5 mL) was added PPh3 (42 mg, 0.2 mmol), Pd(OAc)2 (47.5 %, 47 mg, 0.1 mmol) and NEt3 (0.2 mL, 1.6 mmol) the mixture was sitirred for 10 mins and tert-butyl acrylate (0.2 mL, 1.6 mmol) was added to the flask which was refluxed overnight. The reaction was allowed to cool and was washed with saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 30: 1, 20: 1) provided the title compound as a transparent oil (100 mg, 0.3 mmol, 29 %).

Rf: 0.90 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.77 (3H, s, CH3), 2.33 (3H, s, C02CH3), 3.25 (2H, d, J = 7.1 Hz, CH2), 5.23 (1H, t, J = 7 Hz, CH), 6.31 (1H, d, J = 15.9 Hz, CH), 7.05 (1H, d, J = 8.8 Hz, Ar-H), 7.37 (2H, s, Ar-H), 7.56 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 20.8, 25.7, 28.7, 60.3, 80.5, 120.1, 121.0, 122.7, 126.5, 129.7, 132.6, 133.7, 134.0, 142.8, 150.1, 166.2, 169.1. M/Z ESI: 215 (100%), 353.1 0 [M+Na]+ (50%)

4-[(lE)-3-(tert-butoxy)-3-oxoprop-l-en-l-yl]-2-(3-methylbut-2-en-l-yl)phenyl 4-phenylbutanoate (6c): To a solution of 5c (591 mg, 1.3 mmol) in dry toluene (6.5 mL) was added PPh3 (42 mg, 0.2 mmol), Pd(OAc)2 (47.5 %, 47 mg, 0.1 mmol) and NEt3 (0.2 mL, 1.6 mmol) the mixture was sitirred for 10 mins and tert-butyl acrylate (0.3 mL, 2.0 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 20: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (260 mg, 0.6 mmol, 44 %).

Rf: 0.88 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.67 (3H, s, CH3), 1.76 (3H, s, CH3), 2.05 - 2.14 (2H, m, CH2), 2.59 (2H, t, J = 7.5 Hz, CH2), 2.77 (2H, t, J = 7.6 Hz, CH2), 3.24 (2H, d, J = 7.1 Hz, CH2), 5.22 (1H, t, J = 7.1 Hz, CH), 6.31 (1H, d, J = 15.9 Hz, CH), 7.02 (1H, d, J = 8.9 Hz, Ar-H), 7.22 - 7.25 (3H, m, Ar-H), 7.31 - 7.39 (4H, m, Ar-H), 7.56 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 26.4, 28.2, 28.6, 33.4, 35.0, 80.4, 120.0, 121.0, 122.7, 126.1, 126.5, 128.4, 129.7, 132.5, 133.8, 134.0, 141.0, 142.8, 150.1, 166.3, 171.6.

tert-butyl (2E)-3-{4-[(2-cyclohexylacetyl)oxy]-3-(3-methylbut-2-en-l-yl)phenyl}prop-2-enoate (6d): To a solution of 5d (390 mg, 0.9 mmol) in dry toluene (4 mL) was added PPh3 (26 mg, 0.1 mmol), Pd(OAc)2 (47.5 %, 25 mg, 0.05 mmol) and NEt3 (0.21 mL, 1.5 mmol) the mixture was sitirred for 10 mins and tert-Butyl acrylate (0.21 mL, 1.4 mmol) was added and the reaction refluxed overnight. The reaction was allowed to cool, washed with saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a transpaent oil (370 mg, 0.85 mmol, 95 %).

1H NMR (400 MHz; CDC13): δ 0.90-1.46 (7H, m, cyc-H), 1.55 (9H, s, C(CH3)3), 1.84 (3H, s, CH3), 1.96 (3H, s, CH3), 1.84-1.96 (4H, m, cyc-H), 2.47 (2H, d, J = 7 Hz, CH), 3.24 (2H, d, J = 7.1 Hz, CH2), 5.23 (1H, t, J = 7.1 Hz, CH), 6.31 (1H, d, J = 15.9, CH), 7.04 (1H, d J = 8.8 Hz, Ar-H), 7.39-7.36 (2H, m, Ar-H), 7.55 (1H, d, J = 15.9, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 26.0, 26.1, 28.2, 28.5, 33.0, 34.9, 42.0, 80.5, 119.9, 121.0, 122.7, 126.4, 129.7, 132.4, 133.7, 134.0, 142.9, 150.1, 166.3, 171.2.

tert-but l(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-{[2-(naphthalen-l-yl)acetyl]oxy}phenyl^

(6e): To a solution of 5e (256 mg, 0.6 mmol) in dry toluene (6.5 mL) was added PPh3 (42 mg, 0.2 mmol), Pd(OAc)2 (47.5 %, 47 mg, 0.1 mmol) and NEt3 (0.2 mL, 1.6 mmol) the mixture was sitirred for 10 mins and tert-Butyl aery late (0.1 mL, 0.8 mmol) was added to the flask and the reaction refluxed overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, water, extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a transparent oil (66.1 mg, 0.1 mmol, 17

%).

1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.56 (3H, s, CH3), 1.69 (3H, s, CH3), 2.99 (2H, d, J = 7.1 Hz, CH2), 4.35 (2H, s, CH2), 5.02 (1H, t, J = 7.2 Hz, CH), 6.29 (1H, d, J = 15.9 Hz, CH), 6.99 (1H, d, J = 8.1 Hz, Ar-H), 7.31 - 7.33 (2H, m, Ar-H), 7.47 - 7.61 (5H, m, Ar-H and CH), 7.85 - 7.92 (2H, m, Ar-H), 8.14 (1H, d, J = 8.6 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.7, 25.6, 28.2, 28.3, 39.3, 80.5, 120.0, 120.7, 122.5, 123.6, 125.5, 125.9, 126.3, 126.5, 128.3, 128.4, 128.8, 129.5, 129.8, 132.0, 132.5, 133.5, 133.9, 134.1, 142.8, 150.0, 166.2, 169.6.

(E)-4-(3-(tert-butoxy)-3-oxoprop-l-en-l-yl)-2-(3-methylbut-2-en-l-yl)phenyl benzoate (6f): To a sitirred solution of 5f (270 mg, 0.6 mmol) in dry toluene (12 mL) was added PPh3 (20 mg, 0.07 mmol), Pd(OAc)2 (47.5 %, 17 mg, 0.03 mmol), NEt3 (0.1 mL, 1 mmol) and tert-Butyl acrylate (0.2 mL, 1.3 mmol) and the mixture was refluxed overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, water, extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 20: 1, 10: 1, 5: 1) provided the title compound as a transparent oil (72 mg, 0.2 mmol, 16 %).

1H NMR (400 MHz; CDC13): δ 1.56 (9H, s, C(CH3)3), 1.60 (3H, s, CH3), 1.70 (3H, s, CH3), 3.32 (2H, d, J = 7.0 Hz, CH2), 5.25 (1H, t, J = 7.5 Hz, CH), 6.35 (1H, d, J = 15.9 Hz, CH), 7.18 (1H, d, J = 8.7 Hz, ArCH), 7.43 (2H, s, ArCH), 7.52 - 7.69 (4H, m, ArCH and CH), 8.22 (2H, d, J = 7.7 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.6, 28.2, 28.9, 80.5, 120.1, 121.1, 122.9, 126.6, 128.6, 129.2, 129.8, 130.2, 133.7, 134.3, 138.9, 142.8, 150.4, 164.8, 166.2.

4-[(lE)-3-(tert-butoxy)-3-oxoprop-l-en-l-yl]-2-(3-methylbut-2-en-l-yl)phenyl pyridine-4-carboxylate (6g): To a solution of 5g (650 mg, 1.6 mmol) in dry toluene (10 mL) was added PPh3 (42 mg, 0.2 mmol), Pd(OAc)2 (47.5 %, 40 mg, 0.1 mmol) and NEt3 (0.4 mL, 2.7 mmol) the mixture was sitirred for 10 min and tert-butyl acrylate (0.4 mL, 2.8 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 4: 1, 2: 1, 0: 1) provided the title compound as a yellow oil (350 mg, 0.88 mmol, 54 %).

Rf: 0.31 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.51 (9H, s, C(CH3)3), 1.51 (3H, s,

CH3), 1.64 (3H, s, CH3), 3.26 (2H, d, J = 6.6 Hz, CH2), 5.17 (1H, t, J = 6.2 Hz, CH), 6.32 (1H, d, J = 15.9 Hz, CH), 7.14 (1H, d, J = 8.5 Hz, Ar-H), 7.40 (2H, s Ar-H), 7.55 (1H, d, J = 15.9 Hz, CH), 7.96 (2H, d, J = 4.2 Hz, Ar-H), 8.84 (2H, d, J = 4.2 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.8, 25.6, 28.1, 29.0, 60.3, 80.5, 120.5, 120.8, 122.5, 123.1, 126.7, 130.0, 133.1, 133.9, 134.0, 136.4, 142.5, 149.8, 150.8, 163.3, 166.1.

(E)-4-(3-(tert-butoxy)-3-oxoprop-l-en-l-yl)-2-(3-methylbut-2-en-l-yl)phenyl hexanoate (6h): Following the procedure as described for 6a the title compound was obtained as a white soild (150 mg, 0.4 mmol, 40%).

1H NMR (400 MHz; CDC13): δ 0.89 - 0.96 (3H, m, CH3), 1.28 - 1.41 (6H, m, CH2), 1.55 (9H, s, (CH3)3), 1.71 (3H, s, CH3), 1.77 (3H, s, CH3), 2.58 (2H, t, J = 7.2 Hz, CH2), 3.24 (2H, d, J = 6.8 Hz, CH2), 5.23 (1H, t, J = 7.2 Hz, CH), 6.31 (1H, d, J = 15.9 Hz, CH), 7.04 (1H, d, J = 8.9 Hz, ArCH), 7.37 - 7.40 (2H, m, ArCH), 7.56 (1H, d, J = 16.0 Hz, CH). 13C NMR (100 MHz; CDC13): δ 13.9, 17.8, 22.3, 24.6, 25.7, 28.2, 28.6, 31.3, 34.2, 80.4, 120.0, 121.0, 122.7, 126.4, 129.7, 132.5, 133.7, 134.1, 142.8, 150.2, 166.2, 171.9

tert-butyl (E)-3-(4-((3-(4-fluorophenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylate (6i): To a solution of 5i (250 mg, 0.6 mmol) in dry toluene (6 mL) was added PPh3 (52 mg, 0.2 mmol), Pd(OAc)2 (47.5 %, 48 mg, 0.1 mmol) and NEt3 (0.4 mL, 3.0 mmol) the mixture was sitirred for 10 min and tert- butyl acrylate (0.2 mL, 1.4 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 4: 1, 2: 1, 0: 1) provided the title compound as a yellow oil (160 mg, 0.36 mmol, 60%).

Rf: 0.85 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.56 (9H, s, CH3), 1.68 (3H, s, CH3), 1.76 (3H, s, CH3), 2.91 (2H, t, J = 7.3 Hz, CH2), 3.06 (2H, t, J = 7.4 Hz, CH2), 3.13 (2H, d, J = 7.1 Hz, CH2), 5.18 (1H, t, J = 7.2 Hz, CH), 6.33 (1H, d, J = 15.6 Hz, CH), 6.95 - 7.04 (3H, m, ArCH), 7.23 - 7.28 (2H, m, ArCH), 7.35 - 7.37 (2H, m, ArCH), 7.57 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 28.2, 28.5, 30.0, 35.8, 80.5, 115.2, 115.4, 120.1, 120.9, 122.6, 126.5, 129.7, 129.8, 129.9, 132.6, 133.7, 134.0, 142.8, 150.0, 166.2, 170.9

tert-butyl (E)-3-(4-((3-(3-fluorophenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylate (6j): To a solution of 5j (430 mg, 1.3 mmol) in dry toluene (6 mL) was added PPh3 (78 mg, 0.3 mmol), Pd(OAc)2 (47.5 %, 70 mg, 0.15 mmol) and NEt3 (0.4 mL, 3.0 mmol) the mixture was sitirred for 10 min and tert- butyl acrylate (0.4 mL, 2.8 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (260 mg, 0.6 mmol, 45%).

Rf: 0.51 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.56 (9H, s, CH3), 1.69 (3H, s, CH3), 1.76 (3H, s, CH3), 2.93 (2H, t, J = 7.5 Hz, CH2), 3.09 (2H, t, J = 7.5 Hz, CH2), 3.15 (2H, d, J = 7.1 Hz, CH2), 5.19 (1H, t, J = 7.2 Hz, CH), 6.32 (1H, d, J = 15.9 Hz, CH), 6.93 - 7.01 (3H, m, ArCH), 7.07 (1H, d, J = 7.6 Hz, ArCH), 7.27 - 7.32 (1H, m, ArCH), 7.35 - 7.38 (2H, m, ArCH), 7.56 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 28.2, 28.5, 35.4, 80.5, 113.3, 113.5, 115.2, 115.4, 120.1, 120.9, 122.6, 124.0, 126.5, 129.7, 132.6, 133.7, 134.0, 142.5 142.8, 150.0, 161.7, 166.2, 170.8.

tert-butyl(E)-3-(4-((3-(2-fluorophenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylate (6k): To a solution of 5k (430 mg, 1 mmol) in dry toluene (6 mL) was added PPh3 (78 mg, 0.3 mmol), Pd(OAc)2 (47.5 %, 70 mg, 0.15 mmol) and NEt3 (0.4 mL, 3.0 mmol) the mixture was sitirred for 10 min and tert- butyl acrylate (0.4 mL, 2.8 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (250 mg, 0.6 mmol, 57%).

Rf: 0.73 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.56 (9H, s, CH3), 1.69 (3H, s, CH3), 1.77 (3H, s, CH3), 2.94 (2H, t, J = 7.5 Hz, CH2), 3.13 (2H, t, J = 7.5 Hz, CH2), 3.17 (2H, d, J = 7.1 Hz, CH2), 5.19 (1H, t, J = 7.2 Hz, CH), 6.32 (1H, d, J = 15.9 Hz, CH), 6.99 (1H, d, J = 8.8 Hz, ArCH), 7.03 - 7.12 (2H, m, ArCH), 7.19 - 7.32 (2H, m, ArCH), 7.35 - 7.37 (2H, m, ArCH), 7.56 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 24.6, 25.7, 28.2, 28.6, 34.2, 80.5, 115.3, 120.0, 121.0, 122.6, 124.2, 126.5, 128.3, 129.7, 130.7, 132.6, 133.7, 134.0, 142.8, 150.0, 162.4, 166.2, 170.8.

tert-butyl(E)-3-(4-((3-(4-methoxyphenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylate (61): To a solution of 51 (320 mg, 0.7 mmol) in dry toluene (8 mL) was added PPh3 (53 mg, 0.2 mmol), Pd(OAc)2 (23 mg, 0.1 mmol) and NEt3 (0.2 mL, 1.5 mmol) the mixture was sitirred for 10 min and tert- butyl acrylate (0.2 mL, 1.5 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (200 mg, 0.4 mmol, 47%).

Rf: 0.69 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, CH3), 1.68 (3H, s, CH3), 1.76 (3H, s, CH3), 2.89 (2H, t, J = 7.8 Hz, CH2), 3.04 (2H, t, J = 7.6 Hz, CH2), 3.14 (2H, d, J = 7.2 Hz, CH2), 3.80 (3H, s, CH3), 5.19 (1H, t, J = 7.2 Hz, CH), 6.31 (1H, d, J = 15.9 Hz, CH), 6.88 (2H, d, J = 8.6 Hz, ArCH), 6.97 (1H, d, J = 8.9 Hz, ArCH), 7.21 (2H, d, J = 8.6 Hz, ArCH), 7.35 - 7.37 (2H, m, ArCH), 7.55 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 28.2, 28.4, 30.0, 36.1, 55.2, 80.5, 114.0, 120.0, 121.0, 122.6, 126.4, 129.3, 129.6, 132.0, 132.6, 133.7, 134.0, 142.8, 150.1, 158.2, 166.2, 171.1.

tert-butyl(E)-3-(4-((3-(3-methoxyphenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acty (6m): To a solution of 5m (280 mg, 0.6 mmol) in dry toluene (8 mL) was added PPh3 (39 mg, 0.15 mmol), Pd(OAc)2 (47.5%, 35 mg, 0.08 mmol) and NEt3 (0.2 mL, 1.5 mmol) the mixture was sitirred for 10 min and tert-butyl acrylate (0.2 mL, 1.5 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2:1) provided the title compound as a yellow oil (220 mg, 0.4 mmol, 77%).

Rf: 0.55 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.56 (9H, s, CH3), 1.70 (3H, s, CH3), 1.77 (3H, s, CH3), 2.93 (2H, t, J = 7.8 Hz, CH2), 3.08 (2H, t, J = 7.6 Hz, CH2), 3.17 (2H, d, J = 7.2 Hz, CH2), 3.82 (3H, s, CH3), 5.20 (1H, t, J = 7.2 Hz, CH), 6.33 (1H, d, J = 15.9 Hz, CH), 6.81 (1H, dd, Jl = 2.4 Hz, J2 = 8.6 Hz, ArCH), 6.84 (1H, t, J = 1.8 Hz, ArCH), 6.88 (1H, d, J = 7.6 Hz, ArCH), 6.99 (1H, d, J = 8.8 Hz, ArCH), 7.26 (1H, t, J = 7.8 Hz, ArCH), 7.36 - 7.38 (2H, m, ArCH), 7.57 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 28.2, 30.9, 35.7, 55.1, 80.5, 111.8, 114.2, 120.0, 120.6, 121.0, 122.7, 126.5, 129.6, 129.7, 133.7, 134.1, 141.5, 142.8, 150.1, 150.8, 166.2, 171.0.

tert-butyl(E)-3-(4-((3-(2-methoxyphenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylate (6n): To a solution of 5n (320 mg, 0.7 mmol) in dry toluene (8 mL) was added PPh3 (78 mg, 0.3 mmol), Pd(OAc)2 (34 mg, 0.15 mmol) and NEt3 (0.4 mL, 3 mmol) the mixture was sitirred for 10 min and tert- butyl acrylate (0.4 mL, 2 mmol) added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (150 mg, 0.3 mmol, 47%). Rf: 0.70 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.57 (9H, s, CH3), 1.71 (3H, s, CH3), 1.78 (3H, s, CH3), 2.91 (2H, t, J = 7.8 Hz, CH2), 3.10 (2H, t, J = 7.6 Hz, CH2), 3.19 (2H, d, J = 7.2 Hz, CH2), 3.88 (3H, s, CH3), 5.22 (1H, t, J = 7.2 Hz, CH), 6.33 (1H, d, J = 15.9 Hz, CH), 6.92 (2H, q, J = 7.4 Hz, ArCH), 7.00 (1H, d, J = 8.8 Hz, ArCH), 7.23 - 7.26 (2H, m, ArCH), 7.36 - 7.38 (2H, m, ArCH), 7.57 (1H, d, J = 15.9 Hz, CH).

(E)-2-(3-methylbut-2-en-l-yl)-4-(2-(4,4_^ 3- phenylpropanoate (7): To a solution of 5a (350 mg, 0.8 mmol) in dry toluene (8 mL) was added PPh3 (27 mg, 0.1 mmol), Pd(OAc)2 (12 mg, 0.05 mmol) and NEt3 (0.3 mL, 2 mmol) the mixture was sitirred for 10 min and 4,4,5, 5-tetramethyl-2-vinyl-l,3,2-dioxaborolane (0.2 mL, 1 mmol) was added and the reaction refluxed overnight. The reaction was allowed to cool and was washed with a saturated aqueous NH4C1, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4: 1) provided the title compound as a yellow oil (70 mg, 0.15 mmol, 20%).

Rf: 0.74 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.34 (12H, s, CH3), 1.68 (3H, s, CH3), 1.76 (3H, s, CH3), 2.92 (2H, t, J = 7.1 Hz, CH2), 3.11 (2H, t, J = 7.8 Hz, CH2), 3.14 (2H, d, J = 7.8 Hz, CH2), 5.20 (1H, t, J = 7.8 Hz, CH), 6.12 (1H, d, J = 18.4 Hz, CH), 6.93 (1H, d, J = 8.6 Hz, ArCH), 7.23 - 7.39 (8H, m, ArCH and CH). 13C NMR (100 MHz; CDC13): δ 17.8, 24.8, 25.7, 28.4, 30.9, 35.8, 83.3, 121.1, 122.2, 125.5, 128.3, 128.3, 128.5, 128.6, 128.7, 133.5, 133.5, 135.4, 140.0, 148.7, 149.2, 171.1.

(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-[(3-phenylpropanoyl)oxy]phenyl]prop-2-enoic acid (1): To a solution of 6a in toluene (10 ml) was added chromatography grade silica gel (3.3 g) and the mixture was reflued with vigorous agitation overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over celite pad using 10% methanol in DCM as the solvent. Purified with silica gel flash chromatography using eluent system as Hexane:EtOAc = 2: 1, 1: 1, 0: 1 and solvent evaporated in vacuo to provide the title compound (139.5 mg, 0.38 mmol, 58%). Rf: 0.1 (Hexane:EtOAc = 4: 1). 1H NMR (400 MHz, CDC13): δ 1.69 (3H, s, CH3), 1.77 (3H, s, CH3), 2.94 (2H, t, J = 7.7 Hz, CH2), 3.11 (2H, t, J = 7.6 Hz, CH2), 3.17 (2H, d, J=7.4Hz, H-l"), 5.20 (1H, t, J = 7.3 Hz, CH), 6.40 (1H, d, J = 16 Hz, CH), 7.00 (1H, d, J = 8.3 Hz, ArCH) 7.24-7.42 (7H, m, ArCH), 7.75 (1H, d, J = 16 Hz, CH). 13C NMR (100 MHz, CDC13): δ 17.8, 25.7, 28.4, 30.8, 35.8, 116.7, 120.8, 122.8, 126.5, 126.8, 128.6, 130.1, 131.9, 133.9, 134.3, 139.9, 146.3, 150.6, 170.6, 171.0 M/Z ESI: 363.1 [M-, 100%], 364.2(25%)

(2E)-3-[4-(acetyloxy)-3-(3-methylbut-2-en-l-yl)phenyl]prop-2-enoic acid (8b): To a solution of 6b (100 mg, 0.3 mmol) in dry toluene (5 mL) was added silica gel (3 mL) and the mixture was refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad and the solution concentrated. Purification by column chromatography (Hexane:EtOAc = 4: 1, 2: 1, 1: 1, 0: 1) provided the title compound as a white solid (86 mg, 0.3 mmol, 99 %).

Rf: 0.11 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.73 (3H, s, CH3), 1.78 (3H, s, CH3), 2.34 (3H, s, C02CH3), 3.27 (2H, d, J = 7.7 Hz, CH2), 5.24 (1H, t, J = 7.1 Hz, CH), 6.41 (1H, d, J = 15.9 Hz, CH), 7.09 (1H, d, J = 8.4 Hz, Ar-H), 7.43 (2H, s, Ar-H), 7.75 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.8, 20.8, 25.7, 28.6, 117.1 120.8, 122.9, 126.9, 130.2, 132.0, 134.0, 146.3, 150.7, 169.0, 172.1. m/z (ESI): 273.0 [M - H]- (100%).

(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-[(4-phenylbutanoyl)oxy]phenyl]prop-2-enoic acid (8c): To a solution of 6c (230 mg, 0.5 mmol) in dry toluene (5 mL) was added silica gel (3 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad using 10% methanol in DCM as the solvent. The solvent was evaporated in vacuo and purified by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1 : 1) to provide the title compound as a white solid (12.2 mg, 0.03 mmol, 6 %).

Rf: 0.10 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.68 (3H, s, CH3), 1.76 (3H, s, CH3), 2.12 (2H, q, J = 7.5 Hz, CH2), 2.62 (2H, t, J = 7.5 Hz, CH2), 2.78 (2H, t, J = 7.5 Hz, CH2), 3.25 (2H, d, J =7.1 Hz, CH2), 5.23 (1H, t, J = 7.2 Hz, CH), 6.40 (1H, d, J = 15.0, CH), 7.06 (1H, d, J = 8.5 Hz, Ar-H), 7.23 - 7.26 (3H, m, Ar-H), 7.31 - 7.35 (2H, m, Ar-H), 7.42 - 7.44 (2H, m, Ar-H), 7.76 (1H, d, J = 15.95 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.8, 25.7, 26.2, 26.4, 28.6, 33.4, 35.1, 117.0, 120.8, 122.9, 126.1, 126.9, 128.5, 130.2, 131.9, 134.1, 134.3, 141.0, 146.3, 150.7, 171.6, 171.9. m/z (ESI): 377.1 [M - H]- (100%).

(2E)-3-{4-[(2-cyclohexylacetyl)oxy]--(3-methylbut-2-en-l-yl)phenyl}prop-2-enoic acid (8d): To a solution of 6d (370 mg, 0.85 mmol) in dry toluene (10 mL) was added silica gel (5 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad using 10% methanol in DCM as the solvent which was concentrated in vacuo. Purification by column chromatography (Hexane:EtOAc = 4: 1, 1: 1) provided the title compound as a white solid (130 mg, 0.3 mmol, 40 %).

Rf: 0.14 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.05 - 1.39 (7H, m, cyc-H), 1.72 (3H, s, CH3), 1.79 (3H, s, CH3), 1.84-1.96 (3H, m, cyc-H), 2.47 (2H, d, J = 7 Hz, CH), 3.24 (2H, d, J = 7.1 Hz, CH2), 5.23 (1H, t, J = 7.1 Hz, CH), 6.39 (1H, d J = 15.9, CH), 7.04 (1H, d, J = 8.8 Hz, Ar-H), 7.39-7.36 (2H, m, Ar-H), 7.75 (1H, d, J = 15.9, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 26.0, 28.5, 33.0, 34.9, 41.9, 117.0, 120.8, 122.9, 126.8, 128.3, 128.5, 128.9, 130.1, 131.8, 134.0, 134.3, 146.4, 150.8, 171.1, 172.3. m/z (ESI): 355.1 [M - H]- (100%)

(2E)-3- [3-(3-methylbut-2-en- 1 -yl)-4- { [2-(naphthalen- 1 -yl)acetyl]oxy }phenyl]prop-2-enoic acid (8e) : To a solution of 6e (66.1 mg, 0.15 mmol) in toluene (5 mL) was added silica gel (3 mL) and the mixture was refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite pad® using 10% methanol in DCM as the solvent. The solvent was evaporated in vacuo to provide the title compound as a white solid (34 mg, 0.1 mmol, 60 %).

Rf: 0.20 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.57 (3H, s, CH3), 1.70 (3H, s, CH3), 3.00 (2H, d, J = 7.3 Hz, CH2), 4.36 (2H, s, CH2), 5.03 (1H, t, J = 7.2 Hz, CH), 6.37 (1H, d, J = 15.9 Hz, CH), 7.03 (1H, d, J = 8.2 Hz, Ar-H), 7.34 - 7.38 (2H, m, Ar-H), 7.48 - 7.62 (4H, m, Ar-H) 7.72 (1H, d, J = 15.9 Hz, CH), 7.87 (1H, d, J = 8.1 Hz, Ar-H), 7.89 (1H, dd, Jl = 8.7 Hz, J2 = 21.7 Hz, Ar-H), 8.14 (1H, d, J = 8.5 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.7, 25.6, 28.2, 29.7, 39.3, 117.0, 120.5, 122.7, 123.6, 125.5, 125.9, 126.6, 126.8, 128.3, 128.4, 128.8, 129.7, 130.0, 131.9, 132.0, 133.8, 133.9, 134.3, 146.3, 150.6, 169.6. m/z: (ESI): 399.0 [M - H]- (75 %).

(E)-3-(4-(benzoyloxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (8f): To a solution of 6f (72 mg, 0.2 mmol) in toluene (6 mL) was added silica gel (2 mL) and the mixture was refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite pad® using 10% methanol in DCM as the solvent. The solvent was evaporated in vacuo to provide the title compound as a white solid (32 mg, 0.09 mmol, 50 %).

1H NMR (400 MHz; MeOD): δ 1.61 (3H, s, CH3), 1.72 (3H, s, CH3), 3.35 (2H, d, J = 7.0 Hz, CH2), 5.26 (1H, t, J = 7.5 Hz, CH), 6.45 (1H, d, J = 16.0 Hz, CH), 7.23 (1H, d, J = 8.2 Hz, ArCH), 7.49 - 7.57 (4H, m, ArCH), 7.68 (1H, t, J = 7.0 Hz, ArCH), 7.81 (1H, d, J = 15.9 Hz, CH), 8.23 (2H, d, J = 7.3 Hz, ArCH). 13C NMR (100 MHz; MeOD): δ 17.8, 25.6, 28.8, 117.0, 120.8, 123.0, 127.0, 128.6, 130.2, 130.3, 132.0, 133.7, 134.0, 134.6, 146.3, 151.0, 164.7, 171.1, 171.5.

(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-(pyridine-4-carbonyloxy)phenyl]prop-2-enoic acid (8g): To a solution of 6g (350 mg, 0.9 mmol) in dry toluene (25 mL) was added silica gel (20 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad. Purified by column chromatography (DCM:Mehanol = 10: 1, 5: 1) and solvent was evaporated in vacuo to provide the title compound as a yellow solid (150 mg, 0.4 mmol, 50 %)

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.55 (3H, s, CH3), 1.62 (3H, s, CH3), 3.36 (2H, d, J = 7.0 Hz, CH2), 5.19 (1H, t, J = 7.0 Hz, CH), 6.50 (1H, d, J = 16.0 Hz, CH), 7.26 (1H, d, J = 8.0 Hz, Ar-H), 7.57 (1H, s Ar-H), 7.59 (1H, d, J = 2.1 Hz, Ar-H), 7.69 (1H, d, J = 15.9 Hz, CH), 8.12 (2H, d, J = 6.1 Hz, Ar-H), 8.86 (2H, d, J = 5.1 Hz, Ar-H). 13C NMR (100 MHz; MeOD): δ 16.5, 24.3, 28.9, 60.1, 118.4, 121.2, 122.8, 123.3, 126.6, 129.9, 133.0, 134.2, 143.7, 150.1, 150.3, 163.1, 168.8. m/z (ESI): 338.1 [M + H]+ (100 %)

(E)-3-(4-(hexanoyloxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (8h): Following the procedure as described for 1 the title compound was obtained as a white soild (50 mg, 0.15 mmol, 37%).

1H NMR (400 MHz; MeOD): δ 1.36 - 1.43 (7H, m, CH3 and CH2), 1.50 - 1.62 (2H, m, CH2), 1.69 (3H, s, CH3), 1.76 (3H, s, CH3), 2.57 (2H, t, J = 7.4 Hz, CH2), 3.18 (2H, d, J = 7.0 Hz, CH2), 5.19 (1H, t, J = 7.2 Hz, CH), 6.45 (1H, d, J = 15.7 Hz, CH), 7.01 (1H, d, J = 8.3 Hz, ArCH), 7.52 - 7.54 (2H, m, ArCH), 7.46 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; MeOD): δ 12.8, 16.5, 22.0, 24.2, 24.4, 28.3, 31.0, 33.5, 121.2, 122.6, 126.1, 129.3, 132.8, 132.9, 134.1, 142.3, 150.2, 172.2

(E)-3-(4-((3-(4-fluorophenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (8i): To a solution of 8i (160 mg, 0.36 mmol) in dry toluene (8 mL) was added silica gel (3 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad. Purified by column chromatography (DCM:Mehanol = 10: 1, 5: 1) and solvent was evaporated in vacuo to provide the title compound as a white solid (72 mg, 0.2 mmol, 52%).

Rf: 0.16 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz, MeOD): δ 1.65 (3H, s, CH3), 1.72 (3H, s, CH3), 2.92 (2H, t, J = 7.2 Hz, CH2), 3.08 (2H, t, J = 7.0 Hz, CH2), 3.17 (2H, d, J=7.4Hz, CH2), 5.13 (1H, t, J = 7.0 Hz, CH), 6.40 (1H, d, J = 15.9 Hz, CH), 7.02 (2H, t, J = 8.6 Hz, ArCH), 7.29 (2H, t, J = 8.1 Hz, ArCH), 7.40-7.44 (2H, m, ArCH), 7.62 (1H, d, J = 15.9 Hz, CH) 13C NMR (100 MHz, MeOD): δ 16.5, 24.4, 28.1, 29.5, 35.1, 114.6, 117.9, 121.0, 122.6, 129.7, 132.3, 133.0, 134.2, 136.1, 144.0, 150.4, 160.4, 162.8, 168.8, 171.1,

(E)-3-(4-((3-(3-fluorophenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (8j): To a solution of 8j (260 mg, 0.6 mmol) in dry toluene (8 mL) was added silica gel (5 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad. Purified by column chromatography (DCM:Mehanol = 10: 1, 5: 1) and solvent was evaporated in vacuo to provide the title compound as a white solid (103 mg, 0.3 mmol, 45%). Rf: 0.18 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz, MeOD): δ 1.67 (3H, s, CH3), 1.73 (3H, s, CH3), 2.98 (2H, t, J = 7.0 Hz, CH2), 3.07 (2H, t, J = 7.7 Hz, CH2), 3.12 (2H, d, J=7.1 Hz, CH2), 5.15 (1H, t, J = 7.2 Hz, CH), 6.42 (1H, d, J = 15.9 Hz, CH), 6.93 - 6.99 (2H, m, ArCH), 7.06 (1H, d, J = 8.4 Hz, ArCH), 7.12 (1H, d, J = 7.6 Hz, ArCH), 7.32 (1H, q, Jl = 6.1 Hz, J2 = 7.9 Hz, ArCH), 7.43 (1H, s, ArCH), 7.46 (1H, dd, Jl = 2.1 Hz, J2 = 8.3 Hz, ArCH), 7.63 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz, MeOD): δ 16.5, 24.4, 28.1, 29.9, 30.0, 34.7, 112.8, 114.9, 117.9, 121.0, 122.6, 123.9, 126.3, 129.5, 129.8, 132.3, 133.0, 134.2, 143.0, 144.0, 150.4, 161.7, 168.8, 171.1.

(E)-3-(4-((3-(2-fluorophenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (8k): To a solution of 8k (250 mg, 0.6 mmol) in dry toluene (6 mL) was added silica gel (3 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad. Purified by column chromatography (DCM:Mehanol = 10: 1, 5: 1) and solvent was evaporated in vacuo to provide the title compound as a white solid (78 mg, 0.2 mmol, 35%).

Rf: 0.16 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz, MeOD): δ 1.67 (3H, s, CH3), 1.72 (3H, s, CH3), 2.93 (2H, t, J = 7.3 Hz, CH2), 3.13 (2H, t, J = 7.1 Hz, CH2), 3.12 (2H, d, J = 7.1 Hz, CH2), 5.14 (1H, t, J = 7.1 Hz, CH), 6.41 (1H, d, J = 15.9 Hz, CH), 6.98 (1H, d, J = 8.2 Hz, ArCH), 7.05 - 7.13 (2H, m, ArCH), 7.23 - 7.28 (1H, m, ArCH), 7.33 (1H, t, J = 7.6 Hz, ArCH), 7.41 - 7.45 (2H, m, ArCH), 7.62 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz, MeOD): δ 16.5, 23.9, 24.4, 28.2, 33.6, 114.7, 114.9, 117.9, 121.1, 122.7, 124.0, 126.3, 128.1, 129.5, 130.5, 132.2, 133.0, 134.2, 144.0, 150.4, 168.8, 171.0.

(E)-3-(4-((3-(4-methoxyphenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (81): To a solution of 81 (200 mg, 0.4 mmol) in dry toluene (12 mL) was added silica gel (6 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad. Purified by column chromatography (DCM:Mehanol = 10: 1, 5: 1) and solvent was evaporated in vacuo to provide the title compound as a white solid (73 mg, 0.2 mmol, 42%).

Rf: 0.07 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz, MeOD): δ 1.66 (3H, s, CH3), 1.74 (3H, s, CH3), 2.90 (2H, t, J = 7.1 Hz, CH2), 2.98 (2H, t, J = 7.0 Hz, CH2), 3.07 (2H, d, J = 7.2 Hz, CH2), 3.77 (3H, s, CH3), 5.14 (1H, t, J = 7.2 Hz, CH), 6.41 (1H, d, J = 15.9 Hz, CH), 6.86 (2H, d, J = 8.7 Hz, ArCH), 6.96 (1H, d, J = 8.2 Hz, ArCH), 7.20 (2H, d, J = 8.7 Hz, ArCH), 7.41 (1H, s, ArCH), 7.45 (1H, dd, Jl = 2.1 Hz, J2 = 8.3 Hz, ArCH), 7.62 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz, MeOD): δ 16.5, 24.4, 28.0, 29.6, 35.4, 54.2, 133.5, 117.9, 121.0, 122.7, 126.2, 129.0, 129.4, 132.0, 132.3, 133.0, 134.2, 144.0, 150.5, 158.3, 168.8, 171.4.

(E)-3-(4-((3-(3-methoxyphenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (8m): To a solution of 8m (220 mg, 0.5 mmol) in dry toluene (8 mL) was added silica gel (5 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad. Purified by column chromatography (DCM:Mehanol = 10: 1, 5: 1) and solvent was evaporated in vacuo to provide the title compound as a white solid (60 mg, 0.15 mmol, 32%).

Rf: 0.09 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz, MeOD): δ 1.65 (3H, s, CH3), 1.72 (3H, s, CH3), 2.91 (2H, t, J = 7.1 Hz, CH2), 3.00 (2H, t, J = 7.2 Hz, CH2), 3.09 (2H, d, J = 7.1 Hz, CH2), 3.76 (3H, s, CH3), 5.14 (1H, t, J = 7.2 Hz, CH), 6.40 (1H, d, J = 15.9 Hz, CH), 6.76 - 6.78 (1H, m, ArCH), 6.84 (2H, s, ArCH), 6.95 (1H, d, J = 8.2 Hz, ArCH), 7.21 (1H, t, J = 8.2 Hz, ArCH), 7.39 - 7.43 (2H, m, ArCH), 7.62 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz, MeOD): δ 16.6, 24.5, 28.1, 30.4, 35.1, 54.1, 111.4, 113.8, 117.9, 120.3, 121.1, 122.7, 126.3, 129.1, 129.5, 132.3, 133.0, 134.2, 141.7, 144.0, 150.5, 159.9, 168.8, 171.3.

(E)-3-(4-((3-(2-methoxyphenyl)propanoyl)oxy)-3-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (8n): To a solution of 8n (150 mg, 0.3 mmol) in dry toluene (8 mL) was added silica gel (5 mL) and the mixture refluxed overnight. Upon cooling the reaction mixture was diluted with 10% methanol in DCM and filtered over a celite® pad. Purified by column chromatography (DCM:Mehanol = 10: 1, 5: 1) and solvent was evaporated in vacuo to provide the title compound as a white solid (73 mg, 0.2 mmol, 56%).

Rf: 0.1 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz, MeOD): δ 1.71 (3H, s, CH3), 1.78 (3H, s, CH3), 2.93 (2H, t, J = 7.1 Hz, CH2), 3.10 (2H, t, J = 7.5 Hz, CH2), 3.20 (2H, d, J = 7.2 Hz, CH2), 3.88 (3H, s, CH3), 5.23 (1H, t, J = 7.2 Hz, CH), 6.41 (1H, d, J = 15.9 Hz, CH), 6.92 (2H, q, J = 6.4 Hz ArCH), 7.03 (1H, d, J = 8.9 Hz, ArCH), 7.23 - 7.28 (2H, m, ArCH), 7.42 (2H, s, ArCH), 7.678 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz, MeOD): δ 17.8, 25.7, 26.2, 28.5, 34.1, 55.2, 110.2, 117.0, 120.5, 120.9, 122.9, 126.9, 127.9, 128.2, 130.1, 130.2, 131.8, 133.9, 134.3, 146.4, 150.8, 157.5, 171.5, 172.3.

(E)-(3-(3-methylbut-2-en-l-yl)-4-((3-phenylpropanoyl)oxy)st ryl)boronic acid (7a): The solution of 7 (20 mg, 0.05 mmol) in 1: 1 MeOH/H20 was stirred at 80oC overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a white solid (5 mg, 0.01 mmol, 20%).

Rf: 0.1 (Hexane:EtOAc, 4: 1) 1H NMR (400 MHz; CDC13): δ 1.68 (3H, s, CH3), 1.73 (3H, s, CH3), 2.94 (2H, t, J = 7.2 Hz, CH2), 3.06 (2H, t, J = 7.5 Hz, CH2), 3.11 (2H, d, J = 7.4 Hz, CH2), 5.16 (1H, t, J = 7.2 Hz, CH), 6.31 (1H, d, J = 18.0 Hz, CH), 6.90 (1H, d, J = 8.2 Hz, ArCH), 7.20 - 7.34 (7H, m, ArCH and CH), 7.39 (1H, dd, Jl = 2.1 Hz, J2 = 8.3 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 16.5, 24.4, 28.2, 30.4, 35.2, 121.4, 122.2, 124.9, 126.0, 128.0, 128.1, 128.3, 132.6, 133.6, 135.8, 140.2, 147.1, 149.2,

171.5.

2-bromo-4-iodoaniline (10): To a solution of 4-iodo aniline (1.1 g, 5.0 mmol), in 6 mL of HO Ac, was added a solution of Br2 (250 μΐ., 4.8 mmol) and the mixture stirred overnight at room temperature. The reaction mixture was washed with brine, saturated aqueous NaHC03 and extracted with Et20, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a brown oil (570 mg, 1.9 mmol, 44 %)

Rf: 0.46 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 6.54 (1H, d, J = 8.2 Hz, ArCH), 7.37 (1H, d, J = 8.4 Hz, ArCH), 7.70 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 110.0, 117.3, 131.1, 134.4, 136.9, 139.9, 143.8.

tert-butyl (2E)-3-(4-amino-3-bromophenyl)prop-2-enoate (11): To a solution of (10) (570 mg, 1.9 mmol) in dry toluene (8 mL), was added PPh3 (65.5 mg, 0.2 mmol) and Pd(OAc)2 (47.5 %, 60 mg, 0.1 mmol). tert-Butyl Acrylate (370 μΐ., 2.5 mmol) and NEt3 (420 μΐ., 3.0 mmol) were added and the flask was stirred at reflux overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1) provided the title compound as a brown oil (238.5 mg, 0.8 mmol, 64 %)

Rf : 0.23 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13,): δ 1.51 (9H, s, C(CH3)3), 6.15 (1H, d, J = 15.8 Hz, CH), 6.69 (1H, d, J = 8.1 Hz, ArCH), 7.23 (1H, d, J = 8.2 Hz, ArCH), 7.40 (1H, d, J = 15.8 Hz, CH), 7.55 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.2, 80.2, 109.0, 115.3, 117.0, 126.0, 128.4, 132.4, 142.3, 145.7, 166.6.

tert-butyl (2E)-3-[3-bromo-4-(3-phenylpropanamido)phenyl]prop-2-enoate (13a): To a solution of (11) (290 mg, 1.0 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol). A solution of PhCH2CH2COCl (255 mg, 1.5 mmol) in DCM (2 mL) was added to the mixture followed by addition NEt3 (420 μΕ, 3.0 mmol). The solution was heated to 700C and stirred overnight. The reaction was allowed to cool and washed with a saturated aqueous NaHC03, water and extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a brown oil (40 mg, 0.1 mmol, 10 %).

Rf: 0.51 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 2.78 (2H, t, J = 7.6 Hz, CH2), 3.09 (2H, t, J = 7.6 Hz, CH2), 6.31 (1H, d, J = 15.9 Hz, CH), 7.24 - 7.34 (5H, m, ArCH), 7.44 - 7.48 (2H, m, CH and ArCH), 7.67 (1H, d, J = 1.8 Hz, ArCH), 8.41 (1H, d, J = 8.5 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 31.3, 39.6, 80.6, 120.4, 126.5, 128.0, 128.3, 128.7, 131.4, 136.7, 140.1, 141.2, 165.9, 170.3.

tert-butyl (2E)-3-(3-bromo-4-acetamidophenyl)prop-2-enoate (13b): To a solution of 11 (181 mg, 0.6 mmol) in dry DCM (3 mL) was added DMAP (13 mg, 0.1 mmol) and a solution of CH3COC1 (80 mg, 1 mmol) in DCM (1 mL) followed by the addition of NEt3 (210 μΐ., 1.5 mmol). The solution was heated to 400C and stirred overnight. The reaction was allowed to cool and washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 4: 1, 2: 1, 1: 1) provided the title compound as a yellow oil (140 mg, 0.4 mmol, 68 %)

Rf: 0.20 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 2.26 (3H, s, CH3), 6.30 (1H, d, J = 15.9 Hz, CH), 7.44 (1H, s, NH), 7.47 (1H, d, J = 5.7 Hz, ArCH), 7.62 (2H, d, ArCH and CH), 8.39 (1H, d, J = 7.9 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 24.9, 28.1, 80.6, 113.1, 120.5, 121.4, 128.0, 131.4, 131.6, 136.8, 141.2, 165.9, 168.2.

(2E)-3-[3-bromo-4-(4-phenylbutanamido)phenyl]prop-2-enoic acid (13c): To a solution of 11 (150 mg, 0.5 mmol ) in dry DCM (3 mL) was added DMAP (13 mg, 0.1 mmol) and a solution of PhCH2CH2CH2COCl (185 mg, 1 mmol) in DCM (1 mL) followed by the addition of NEt3 (140 μΕ, 1 mmol). The reaction was heated to 400C and stirred overnight. The reaction was allowed to cool and washed with saturated aqueous NaHC03 and water, extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1, 1 : 1) provided the title compound as a yellow oil (20 mg, 0.05 mmol, 10 %).

Rf: 0.4 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 2.11 (2H, d, J = 7.4 Hz, CH2), 2.46 (2H, d, J = 7.1 Hz, CH2), 2.75 (2H, d, J = 7.4 Hz, CH2), 6.32 (1H, d, J = 15.8 Hz, CH), 7.23 - 7.34 (5H, m, ArCH), 7.46 - 7.49 (2H, m, ArCH and CH), 7.68 (1H, s, ArCH), 8.24 (1H, d, J = 8.5 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 26.7, 28.2, 34.9, 37.0, 80.7, 113.2, 120.4, 121.4, 125.3, 126.1, 128.0, 128.2, 128.3, 128.5, 128.5, 129.0, 131.4, 131.6, 136.8, 141.1, 141.2, 165.9, 170.9.

tert-butyl (2E)-3-[3-bromo-4-(2-cyclohexylacetamido)phenyl]prop-2-enoate (13d): To a solution of 11 (150 mg, 0.5 mmol) in dry DCM (3 mL) was added DMAP (13 mg, 0.1 mmol) and a solution of cyclohexylacetyl chloride (160 mg, 1 mmol) in DCM (1 mL), followed by the addition of NEt3 (140 μΐ_^, 1 mmol). The reaction was heated to 400C and stirred overnight. The reaction was allowed to cool and washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a yellow oil (100 mg, 0.2 mmol, 46 %).

Rf: 0.54 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 0.9-1.37 (7H, m, CH2), 1.53 (9H, s, C(CH3)3), 1.67-1.90 (4H, m, CH2), 2.31 (2H, d, J = 6.8 Hz, CH2), 6.30 (1H, d, J = 15.8 Hz, CH), 7.44 - 7.47 (2H, m, ArCH and CH), 7.69 (1H, s, ArCH), 8.42 (1H, d, J = 8.2 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 26.0, 26.1, 26.2, 28.1, 33.1, 33.1, 35.5, 46.1, 80.6, 113.2, 120.3, 121.4, 128.0, 131.4, 131.5, 136.8, 141.2, 165.9, 170.7, 174.2.

tert-butyl (2E)-3-{3-bromo-4-[2-(naphthalen-l-yl)acetamido]phenyl}prop-2-enoate (13e): To a solution of 11 (183.1 mg, 0.6 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol) and a solution of naphthacetyl chloride (205 mg, 1 mmol) in DCM (1 mL), followed by addition of NEt3 (210 μΕ, 1.5 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a brown oil (210 mg, 0.4 mmol, 75 %).

Rf: 0.52 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 4.24 (2H, s, CH2), 6.24 (1H, d, J = 15.9 Hz, CH), 7.37 - 7.58 (7H, m, Ar-H and CH), 7.72 (1H, s, Ar-H), 7.90 - 7.92 (1H, m, Ar-H), 8.02 (1H, d, J = 7.7 Hz, Ar-H), 8.40 (1H, d, J = 8.4 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 28.2, 43.0, 80.6, 113.1, 120.3, 120.8, 123.6, 125.7, 126.4, 127.2, 127.8, 128.8, 128.9, 129.1, 130.0, 131.2, 131.6, 132.0, 134.1, 136.6, 141.2, 165.9, 169.1

tert-butyl (2E)-3-[3-(3-methylbut-2-en-l-yl)-4-(3-phenylpropanamido)phenyl]prop-2-enoate (14a): To a solution of 13a (40 mg, 0.1 mmol) in dry DMF (2 mL) was added CsC03 (65 mg, 0.2 mmol) and Pd(dppf)C12 (16 mg, 0.02 mmol). Prenyl boronic acid pinacol ester (44 μΐ., 0.2 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was filtered through a celite® pad with EtOAc. The solvent was evaporated in vaccuo, re-dissolved in DCM and the residual DMF removed by washing with copious amounts of water in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (20 mg, 0.04 mmol, 44 %)

Rf: 0.30 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.74 (3H, s, CH3), 1.77 (3H, s, CH3), 2.63 (2H, t, J = 7.3 Hz, CH2), 3.06 (2H, t, J = 7.1 Hz, CH2), 3.20 (2H, d, J = 6.2 Hz, CH2), 5.14 (1H, t, J = 6.4 Hz, CH), 6.31 (1H, d, J = 16.1 Hz, CH), 7.23 - 7.33 (6H, m, Ar-H), 7.39 (1H, d, J = 8.3 Hz, Ar-H), 7.53 (1H, d, J = 16.0 Hz, CH), 8.04 (1H, d, J = 7.6 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 18.0, 25.7, 28.2, 31.3, 31.6, 39.7, 80.4, 119.2, 121.3, 122.4, 126.4, 126.8, 128.3, 128.6, 129.4, 134.8, 137.6, 140.5, 143.0, 166.4, 170.1.

tert-butyl (2E)-3-[4-acetamido-3-(3-methylbut-2-en-l-yl)phenyl]prop-2-enoate (14b): To a solution of 13b (140 mg, 0.4 mmol) in dry DMF (2 mL) was added CsC03 (230 mg, 0.7 mmol) and Pd(dppf)C12 (40 mg, 0.05 mmol) and the flask was flushed with nitrogen again. Prenyl boronic acid pinacol ester (140 μΐ., 0.6 mmol) was added and the reaction was heated at 900C overnight. The reaction was allowed to cool and was extracted over a celite® pad with EtOAc. The solvent was evaporated in vaccuo and residual DMF was removed by washing with copious amounts of water in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1, 1 :2, 1:5, 0: 1) to provide the title compound as a transparent oil (51 mg, 0.5 mmol, 38 %)

Rf: 0.09 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.81 (3H, s, CH3), 1.83 (3H, s, CH3), 2.10 (3H, s, CH3), 3.33 (2H, d, J = 6.3 Hz, CH2), 5.21 (1H, t, J = 5.2 Hz, CH), 6.30 (1H, d, J = 15.8 Hz, CH), 7.29 (1H, d, J = 8.2 Hz, Ar-H), 7.41 (1H, s, Ar-H), 7.52 (1H, d, J = 15.9 Hz, CH), 8.01 (1H, d, J = 7.8 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 24.8, 25.7, 28.2, 31.6, 80.4, 119.2, 121.4, 122.5, 126.8, 128.8, 129.4, 130.9, 134.7, 137.8, 143.0, 166.4, 168.0.

tert-butyl (2E)-3-[3-(3-methylbut-2-en-l-yl)-4-(4-phenylbutanamido)phenyl]prop-2-enoate (14c): To a solution of 13c (20 mg, 0.05 mmol) in dry DMF (3 mL) was added Cs2C03 (230 mg, 0.8 mmol) and Pd(dppf)C12 (80 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (140 μΐ., 0.6 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a celite® pad with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4:1, 2: 1, 1: 1, 0: 1) provided the title compound as a transparent oil (17 mg, 0.04 mmol, 80 %).

1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.73 (3H, s, CH3), 1.74 (3H, s, CH3), 2.06 (2H, d, J = 7.4 Hz, CH2), 2.32 (2H, d, J = 7.1 Hz, CH2), 2.73 (2H, d, J = 7.4 Hz, CH2), 3.31 (2H, d, J = 6.5 Hz, CH2), 5.18 (1H, t, J = 7.2 Hz, CH), 6.31 (1H, d, J = 16.8 Hz, CH), 7.20 - 7.42 (7H, m, Ar-H), 7.53 (1H, d, J = 16.2 Hz, CH), 8.10 (1H, d, J = 8.2 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 17.9, 25.6, 26.9, 28.2, 31.7, 35.1, 36.9, 37.0, 80.3, 119.1, 121.4, 122.1, 126.1, 126.9, 128.4, 128.5, 129.5, 130.7, 134.9, 137.9, 141.2, 143.0, 166.5, 170.7.

tert-butyl (2E)-3-[4-(2-cyclohexylacetamido)-3-(3-methylbut-2-en-l-yl)phenyl]prop-2-enoate (14d): To a solution of 13d (100 mg, 0.2 mmol) in dry DMF (3 mL) under was added CsC03 (230 mg, 0.8 mmol) and Pd(dppf)C12 (80 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (140 μΐ., 0.6 mmol) was added and the flask heated at 900C overnight. The reaction was allowed to cool and was extracted over a celite® pad with EtOAc and concentrated in vacuo. Residual DMF was removed by washing with copious amounts of water in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1 : 1, 0: 1) provided the title compound as a transparent oil (20 mg, 0.05 mmol, 21 %).

Rf: 0.42 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 0.99 - 1.32 (7H, m, CH2), 1.54 (9H, s, C(CH3)3), 1.71 (4H, m, CH2), 1.82 (3H, s, CH3), 1.84 (3H, s, CH3), 2.18 (2H, d, J = 6.4 Hz, CH2), 3.34 (2H, d, J = 6.3 Hz, CH2), 5.22 (1H, t, J = 6.8 Hz, CH), 6.31 (1H, d, J = 15.8 Hz, CH), 7.31 (1H, d, J = 14.0 Hz, CH), 7.40 (1H, s, CH), 7.53 (1H, d, J = 16.5 Hz, CH), 8.14 (1H, d, J = 8.7 Hz, Ar-H). 13C NMR (100 MHz; CDC13): δ 18.1, 25.7, 26.0, 26.1, 28.2, 31.7, 33.2, 35.6, 46.2, 80.3, 119.0, 121.5, 126.9, 128.2, 129.0, 129.4, 130.3, 130.6, 134.8, 138.0, 143.1, 166.5, 170.5.

tert-butyl (2E)-3-[3-(3-methylbut-2-en -yl)-4-[2-(naphthalen -yl)acetamido]phenyl]prop-2-enoate (14e): To a solution of 13e (210 mg, 0.4 mmol) in dry DMF (2 mL) was added CsC03 (230 mg, 0.8 mmol) and Pd(dppf)C12 (80 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (140 μΐ., 0.6 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and extracted over a celite® pad with EtOAc. The solvent was evaporated and residual DMF was removed by washing with copious amounts of water in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1, 0: 1) to provide the title compound as a transparent oil (50 mg, 0.1 mmol, 24.5 %).

Rf: 0.23 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 1.58 (3H, s, CH3), 1.65 (3H, s, CH3), 3.08 (2H, d, J = 5.0 Hz, CH2), 4.09 - 4.17 (2H, m, CH2), 4.94 (1H, t, J = 7.1 Hz, CH), 6.28 (1H, d, J = 15.9 Hz, CH), 7.25 - 7.57 (7H, m, Ar-H and CH), 7.88 (2H, t, J = 7.9 Hz, Ar- H), 8.09 (1H, d, J = 8.4 Hz, Ar-H), 8.20 (1H, d, J = 7.6 Hz, Ar-H), 8.34 (lH,s, NH). 13C NMR (100 MHz; CDC13): δ 25.6, 28.2, 30.8, 59.3, 60.4, 73.2, 80.4, 119.2, 120.0, 121.9, 123.7, 125.2, 126.1, 126.4, 126.7, 126.9, 128.9, 129.3, 129.8, 131.0, 131.5, 134.2, 134.5, 135.6, 136.8, 143.0, 166.5, 170.7

(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-(3-phenylpropanamido)phenyl]prop-2-enoic acid (15a): To a solution of 14a (20 mg, 0.04 mmol) in dry toluene (10 mL) was added silica gel (3 mL) and the suspension was stirred at reflux overnight. The reaction was allowed to cool and the mixture was filtered after diluting with 20 % MeOH in DCM, dried (Na2S04), filtered and the solvent evaporated in vacuo to provide the title compound as a white solid (9.3 mg, 0.02 mmol, 50 %)

Rf: 0.00 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.70 (3H, s, CH3), 1.77 (3H, s, CH3), 2.72 (2H, t, J = 7.0 Hz, CH2), 3.03 (2H, t, J = 7.3 Hz, CH2), 3.21 (2H, d, J = 6.9 Hz, CH2), 5.19 (1H, t, J = 7.0 Hz, CH), 6.42 (1H, d, J = 15.8 Hz, CH), 7.14 - 7.30 (5H, m, Ar-H), 7.34 - 7.46 (3H, m, Ar-H), 7.61 (1H, d, J = 16.5 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 24.4, 29.4, 31.3, 37.8, 117.7, 121.3, 125.6, 125.9, 126.1, 127.8, 128.1, 128.1, 128.8, 132.3, 133.2, 136.5, 137.0, 140.6, 144.2, 169.0, 172.6. m/z (ESI): 364.2 [M + H] + (47.5 %), 386.3 [M + Na]+ (45 %). HRMS-ESI: (m/z) calculated for C23H25N03, 386.1727; found, 386.1729

(2E)-3-[4-acetamido-3-(3-methylbut-2-en-l-yl)phenyl]prop-2-enoic acid (15b): To a solution of 14b (51.0 mg, 0.5 mmol) in dry toluene (6 mL) was added silica gel (3 mL) and heated at reflux overnight. The reaction was allowed to cool and was filtered with 20 % MeOH in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (DCM:MeOH = 1 :0, 9: 1, 4: 1) provided the title compound as a white solid (20.3 mg, 0.07 mmol, 50 %)

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.75 (3H, s, CH3), 1.78 (3H, s, CH3), 2.16 (3H, s, CH3), 3.37 (2H, d, J = 6.9 Hz, CH2), 5.25 (1H, t, J = 6.4 Hz, CH), 6.43 (1H, d, J = 16.0 Hz, CH), 7.43 - 7.58 (3H, m, Ar-H), 7.63 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz; MeOD): δ 21.7, 24.4, 29.3, 29.6, 31.6, 117.7, 121,3, 125.7, 126.1, 132.3, 133.2, 136.4, 137.2, 144.2, 170.7. m/z (ESI): 296.1 [M + Na] + (100 %), 274.2 [M + H]+ (95 %).

(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-(4-phenylbutanamido)phenyl]prop-2-enoic acid (15c): To a solution of 14c (17 mg, 0.04 mmol) in dry toluene (6 mL) was added silica gel (3 mL) and the reaction refluxed overnight. The reaction was allowed to cool and was filtered with 20% MeOH in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 4: 1, 2: 1, 1: 1) provided the title compound as a white solid (7.3 mg, 0.02 mmol, 50 %).

Rf: 0.00 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.74 (3H, s, CH3), 1.75 (3H, s, CH3), 2.07 (2H, d, J = 7.5 Hz, CH2), 2.33 (2H, d, J = 7.0 Hz, CH2), 2.73 (2H, d, J = 7.1 Hz, CH2), 3.33 (2H, d, J = 6.5 Hz, CH2), 5.19 (1H, t, J = 6.3 Hz, CH), 6.39 (1H, d, J = 16.9 Hz, CH), 7.20 - 7.46 (7H, m, Ar-H), 7.73 (1H, d, J = 16.3 Hz, CH), 8.17 (1H, d, J = 8.6 Hz, Ar-H). 13C NMR (100 MHz; MeOD): δ 13.0, 16.6, 19.4, 24.4, 27.3, 29.8, 34.9, 35.4, 60.1, 119.3, 121.5, 125.6, 126.1, 127.8, 128.1, 128.8, 132.6, 133.2, 136.5, 141.5, 143.0, 173.3. m/z (ESI): 378.3 [M + H]+ (100 %), 400.3 [M + Na]+ (100 %).

(2E)-3-[4-(2-cyclohexylacetamido)-3-(3-methylbut-2-en-l-yl)phenyl]prop-2-enoic acid (15d): To a solution of 14d (20 mg, 0.05 mmol) in dry toluene (6 mL) was added silica gel (3 mL) and heated at reflux overnight. The reaction was allowed to cool and was filtered with 20% MeOH in DCM, dried (Na2S04) filtered and concentrated in vacuo. Purification by column chromatography (Hexane:EtOAC = 4:1, 2: 1, 1 : 1) Provided the title compound as a white solid (13.2 mg, 0.03 mmol, 93 %).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.03 - 1.38 (7H, m, CH2), 1.73 (3H, s, CH3), 1.78 (3H, s, CH3), 1.78 - 1.90 (4H, m, CH2), 2.29 (2H, d, J = 6.9 Hz, CH2), 3.37 (2H, d, J = 6.9 Hz, CH2), 5.27 (1H, t, J = 7.7 Hz, CH), 6.43 (1H, d, J = 15.9 Hz, CH), 7.43 - 7.49 (3H, m, Ar-H), 7.63 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 24.4, 25.8, 25.9, 29.3, 29.6, 32.8, 35.5, 44.0, 117.9, 121.4, 125.7, 126.2, 129.0, 132.3, 133.3, 136.5, 137.1, 144.1, 173.0. m/z (ESI): 356.3 [M + H]+ (100 %), 378.2 [M + Na]+ (75 %).

(2E)-3-[3-(3-methylbut-2-en-l-yl)-4-[2-(naphthalen-l-yl)acetamido]phenyl]prop-2-enoic acid (15e): To a solution of 14e (50 mg, 0.1 mmol) in dry toluene (6 mL) was added silica gel (3 mL) and stirred at reflux overnight. The reaction was allowed to cool and was filtered with 20 % MeOH in DCM, dried (Na2S04) filtered and concentrated in vacuo. Purification by column chromatography (Hexane:EtOAc = 4: 1, 2: 1, 1 : 1) provided the title compound as a white solid (20.7 mg, 0.05 mmol, 51.8 %).

Rf: 0.01 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.80 (6H, s, 2x CH3), 3.36 (2H, s, CH2), 3.45 (2H, d, J = 5.8 Hz, CH2), 5.23 (1H, t, J = 7.7 Hz, CH), 6.43 (1H, d, J = 16.4 Hz, CH), 7.43 - 7.64 (7H, m, Ar-H and CH), 7.88 - 7.95 (3H, m, Ar-H), 8.37 (1H, d, J = 7.9 Hz, Ar-H). 13C NMR (100 MHz; MeOD): δ 24.5, 30.5, 72.7, 120.7, 122.7, 124.0, 124.8, 125.4, 125.7, 125.8, 126.3, 128.3, 128.6, 129.2, 131.3, 131.3, 133.5, 134.2, 134.8, 136.0, 137.1, 144.0, 172.4. m/z (ESI): 397.9 [M - H] - (20 %)

methyl (E)-3-(3-hydroxyphenyl)acrylate (16a): To a solution of m-coumaric acid (1 g, 6 mmol) in methanol (10 mL), was added sulphuric acid (0.6 mL) and the mixture refluxed overnight. The reaction mixture was allowed to cool and washed with brine, water, extracted in DCM, dried (Na2S04), filtered and concentrated to provide the title compound as a white solid. (1 g, 5.6 mmol, 93 %).

Rf: 0.29 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz, CDC13): δ 3.82 (3H, s, -OCH3), 6.42 (1H, d, J = 17 Hz, CH) 6.89 (1H, d, J = 8.13 Hz, Ar-H), 7.02 (1H, s, Ar-H), 7.11 (1H, d J = 7.5 Hz, Ar-H), 7.65 (1H, d, J = 17.0 Hz, CH). 13C NMR (100MHz, CDC13): δ 51.9, 60.5, 114.3, 119.1, 120.3, 134.0, 134.9, 143.4, 167.0, 171.4.

methyl (E)-3-(4-bromo-3-hydroxyphenyl)acrylate (17): To a solution of 16a (1 g, 5.6 mmol), in HOAc (8 mL) was added a solution of Br2 (310 μΐ., 6 mmol) in HOAc (2 mL) and the solution stirred at room temperature for 5 hr. A further solution of Br2 (85 μΕ, 1.6 mmol) in HOAc (0.9 mL) and the mixture stirred overnight at room temperature. The reaction mixture was washed with brine, saturated aqueous NaHC03 and extracted in Et20, dried (Na2S04), filtered and concentrated. Purification by column chromatography (16 % DCM in EtOAc:Hexane = 1 : 1) provided the title compound as a brown oil (610 mg, 2.3 mmol, 35 %).

Rf: 0.23 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 3.83 (3H, s, -OCH3), 6.33 (1H, d, J = 15.0 Hz, CH), 6.79 (1H, d, J = 8.6 Hz, ArCH), 7.12 (1H, s, Ar-H), 7.42 (1H, d, J = 8.5 Hz, Ar-H), 7.99 (1 H, d, J = 15.9 Hz, CH). 13C NMR (100MHz; CDC13): δ 51.9, 114.3, 115.3, 119.2, 120.2, 134.0, 143.5, 155.9, 167.2, 171.7.

(E)-3-(4-bromo-3-hydroxyphenyl)acrylic acid (17a): To a solution of 17 (330 mg, 1.3 mmol) in water (8 mL) and THF (2 mL) was added NaOH (100 mg, 2.5 mmol) and the reaction refluxed overnight. The solution was allowed to cool and was acidified with AcOH, washed with water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purifcation by column chromatography (Hexane:EtOAc = 9:1, 4: 1, 2: 1, 1: 1, 0: 1) provided the title compound as a white solid (150 mg, 0.6 mmol, 45%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 6.39 (1H, d, J = 15.8 Hz, CH), 6.78 (1H, dd, Jl = 2.9 Hz, J2 = 8.7 Hz, ArCH), 7.15 (1H, d, J = 2.9 Hz, ArCH), 7.44 (1H, d, J = 8.7 Hz, ArCH), 7.97 (1 H, d, J = 15.9 Hz, CH). 13C NMR (100MHz; MeOD): δ 113.6, 113.7, 118.9, 120.5, 133.6, 134.6, 142.9, 157.7, 168.3.

(E)-3-(4-bromo-3-((3-phenylpropanoyl)oxy)phenyl)acrylic acid (18): To a solution of (17a) (280 mg, 0.8 mmol) in DCM (8 mL) was added DMAP (12 mg, 0.1 mmol), NEt3 (210 μΐ., 1.5 mmol) and PhCH2CH2COCl (400 mg, 2.5 mmol) in DCM (2 mL) and the reaction stirred overnight at room temperature. The reaction was washed with saturated aqueous NaHC03 and water, dried (Na2S04), filtered and concentrated. Purifcation by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1 : 1, 0:1) provided the title compound as a white solid (110 mg, 0.3mmol, 36%).

Rf: 0.1 (Hex:EtOAc = 4: 1). 1H NMR (CDC13, 400 MHz): δ 2.94 (2H, t, J = 7.5 Hz, CH2), 3.11 (2H, t, J = 7.5 Hz, CH2), 6.37 (1H, d, J = 15.8 Hz, CH), 6.96 (1H, m, ArCH), 7.31 (6H, m, ArCH), 7.62 (1H, d, J = 8.6 Hz, ArCH), 8.12 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz, CDC13): δ 30.9, 35.8, 120.8, 120.9, 121.9, 125.0, 126.6, 128.4, 128.6, 134.2, 135.1, 139.7, 144.4, 150.0, 171.0, 171.3.

(E)-3-(4-(3-methylbut-2-en-l-yl)-3-((3-phenylpropanoyl)oxy)phenyl)acrylic acid (19a): To a solution of (18) (430 mg, 1.1 mmol) in dry DMF (8 mL) was added CsC03 (555 mg, 1.7 mmol) and Pd(dppf)C12 (50 mg, 0.06 mmol). Prenyl boronic acid pinacol ester (330 μΕ, 1.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was filtered through a celite® pad with EtOAc, the solvent was evaporated and the residue re-dissolved in DCM. The residual DMF was removed by washing with copious amounts of water in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAC = 9: 1, 4: 1, 2: 1, 1: 1, 0: 1) provided the title compound as a yellow oil (120 mg, 0.3 mmol, 27%).

Rf: 0.10 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.72 (3H, s, CH3), 1.77 (3H, s, CH3), 2.90 (2H, t, J = 7.2 Hz, CH2), 3.04 (2H, t, J = 7.2 Hz, CH2), 3.43 (2H, d, J = 6.7 Hz, CH2), 5.15 (1H, t, J = 5.9 Hz, CH), 6.29 (2H, d, J = 15.7 Hz, CH), 6.94 (1H, d, J = 7.2 Hz, Ar-H), 7.16 - 7.33 (7H, m, Ar-H), 7.93 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 24.4, 30.5, 31.3, 35.3, 119.0, 119.9, 122.3, 122.9, 126.0, 128.14, 128.18, 130.4, 132.3, 134.0, 138.6, 140.2, 141.5, 149.3, 168.5, 171.7. m/z (ESI): 387.2 [M + Na]+ (100 %), 365.2 [M + H]+ (70 %). HRMS-ESI: (m/z) calculated for C23H2404, 363.1602; found, 363.1609.

(E)-3-(4-allyl-3-((3-phenylpropanoyl)oxy)phenyl)acrylic acid (19b): To a solution of (18) (110 mg, 0.3 mmol) in dry DMF (4 mL) was added CsC03 (75 mg, 0.4 mmol) and Pd(dppf)C12 (13 mg, 0.01 mmol). Allyl boronic acid pinacol ester (70 μΐ., 0.4 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was filtered through a celite® pad with EtOAc, the solvent was evaporated and the residue re-dissolved in DCM. The residual DMF was removed by washing with copious amounts of water in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAC = 9: 1, 4: 1, 2: 1, 1 : 1, 0: 1) provided the title compound as a yellow oil (60 mg, 0.2 mmol, 60%).

Rf: 0.10 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 2.93 (2H, t, J = 7.5 Hz, CH2), 3.11 (2H, t, J = 7.5 Hz, CH2), 3.53 (2H, d, J = 6.1 Hz, CH2), 5.01 (1H, dd, Jl = 1.5 Hz, J2 = 17.0 Hz, CH2), 5.12 (1H, dd, Jl = 1.5 Hz, J2 = 10.1 Hz, CH2), 5.90 - 6.00 (1H, m, CH), 6.33 (2H, d, J = 15.7 Hz, CH), 7.02 (1H, dd, Jl = 2.4 Hz, J2 = 8.3 Hz, ArCH), 7.20 - 7.38 (7H, m, ArCH), 8.03 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 30.9, 35.9, 36.9, 116.7, 119.4, 119.5, 123.6, 126.5, 128.4, 128.6, 131.3, 134.1, 136.1, 137.0, 139.9, 143.4, 149.3 171.3, 171.5.

tert-butyl (2E)-3-(3-amino-4-bromophenyl)prop-2-enoate (21a): To a solution of 2-bromo-5-iodo aniline (250 mg, 0.8 mmol) in dry toluene (6 mL) was added PPh3 (26 mg, 0.1 mmol) and Pd(OAc)2 (47.5 %, 24 mg, 0.05 mmol). tert-butyl acrylate (160 μΐ., 1.1 mmol) and NEt3 (210 μΐ., 1.5 mmol) were added and the reaction was refluxed overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc gradient = 9: 1, 4: 1, 2: 1, 1 : 1, 0: 1) provided the title compound as a white solid (160 mg, 0.5 mmol, 64 %).

Rf: 0.19 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 6.25 (1H, d, J = 15.9 Hz, CH), 6.60 (1H, s, Ar-H), 6.92 (1H, s, Ar-H), 7.34 (1H, d, J = 8.4 Hz, Ar-H), 7.89 (1H, d J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 28.18, 80.7, 113.5, 118.3, 122.4, 131.9, 133.7, 134.9, 142.1, 145.8, 165.8.

(E)-2-bromo-5-(2-(4,4,5,5 etramethyl-l,3,2-dioxaborolan-2-yl)vinyl)aniline (21b): To a solution of 2- bromo-5-iodo aniline (300 mg, 1 mmol) in dry toluene (10 mL) was added PPh3 (26 mg, 0.1 mmol) and Pd(OAc)2 (11 mg, 0.05 mmol). 4,4,5,5-tetramethyl-2-vinyl-l,3,2-dioxaborolane (170 μΐ., 1 mmol) and NEt3 (225 μΐ., 1.5 mmol) were added and the reaction was refluxed overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc gradient = 9: 1, 4: 1, 2: 1, 1: 1, 0: 1) provided the title compound as a brown oil (64 mg, 0.15 mmol, 15%).

Rf: 0.13 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.33 (12H, s, CH3), 6.06 (1H, d, J = 18.2 Hz, CH), 6.56 (1H, dd, Jl = 2.6 Hz, J2 = 8.4 Hz, ArCH), 6.96 (1H, d, J = 2.6 Hz, ArCH), 7.32 (1H, d, J = 8.4 Hz, ArCH), 7.65 (1H, d J = 18.2 Hz, CH). 13C NMR (100 MHz; CDC13): δ 24.8, 83.4, 113.1, 113.6, 117.6, 133.4, 137.7, 145.0, 147.7.

tert-butyl (E)-3-(4-bromo-3-(3-phenylpropanamido)phenyl)acrylate (23a): To a solution of 21a (160 mg, 0.5 mmol) in dry DCM (9 mL) was added DMAP (8 mg, 0.6 mmol), a solution of PhCH2CH2COCl (170 mg, 1 mmol) in DCM (2 mL) and NEt3 (0.1 mL, 1 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1, 1 : 1) provided the title compound as a white solid (200 mg, 0.4 mmol, 88 %).

Rf: 0.32 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 2.68 (2H, t, J = 7.4 Hz, CH2), 3.03 (2H, t, J = 7.4 Hz, CH2), 6.29 (1H, d, J = 15.8 Hz, CH), 7.18 - 7.29 (5H, m, Ar-H), 7.43 (1H, d, J = 8.3, Ar-H), 7.76 (1H, s, Ar-H), 7.84 (1H, s, Ar-H), 7.89 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 28.1, 31.4, 39.2, 80.9, 118.7, 119.5, 123.2, 126.4, 128.3, 128.6, 133.5, 134.9, 137.5, 140.4, 141.6, 165.8, 170.8

tert-butyl (E)-3-(4-bromo-3-cinnamamidophenyl)acrylate (23b): To a solution of 21a (190 mg, 0.6 mmol) in dry DCM (9 mL) was added DMAP (13 mg, 0.1 mmol), a solution of cinnamoyl chloride (166 mg, 1 mmol) in DCM (2 mL) and NEt3 (0.1 mL, 1 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow solid (100 mg, 0.2 mmol, 36%).

Rf: 0.33 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 6.34 (1H, d, J = 15.8 Hz, CH), 6.62 (1H, d, J = 15.5 Hz, CH), 7.31 - 7.37 (3H, m, ArCH), 7.46 - 7.49 (4H, m, ArCH), 7.76 (1H, d, J = 15.9 Hz, CH) 7.91 (1H, d, J = 15.9 Hz, CH), 8.04 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 14.2, 21.1, 28.1, 60.4, 81.0, 123.2, 127.9, 128.9, 130.1, 133.6, 134.3, 134.9, 137.8, 141.6, 142.9, 164.4, 165.8, 171.3.

tert-butyl (E)-3-(4-bromo-3-(3-(4-fluorophenyl)propanamido)phenyl)acrylate (23c): To a solution of 21a (140 mg, 0.5 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-(4- fluorophenyl)propanoyl chloride (223 mg, 1.2 mmol) in DCM (2 mL) and NEt3 (0.2 mL, 3 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow solid (150 mg, 0.3 mmol, 70%).

Rf: 0.13 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 2.65 (2H, t, J = 7.4 Hz, CH2), 3.00 (2H, t, J = 7.6 Hz, CH2), 6.29 (1H, d, J = 15.8 Hz, CH), 6.94 (2H, t, J = 8.6 Hz, ArCH), 7.14 (2H, t, J = 8.5 Hz, ArCH), 7.25 - 7.28 (1H, m, ArCH), 7.45 (1H, d, J = 8.6, ArCH), 7.86 - 7.90 (2H, m, ArCH and CH).

tert-butyl (E)-3-(4-bromo-3-(3-(3-fluorophenyl)propanamido)phenyl)acrylate (23d): To a solution of 21a (250 mg, 0.8 mmol) in dry DCM (8 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-(3- fluorophenyl)propanoyl chloride (250 mg, 1.5 mmol) in DCM (2 mL) and NEt3 (0.2 mL, 3 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow solid (400 mg, 0.8 mmol, 94%).

Rf: 0.5 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 2.67 (2H, t, J = 7.4 Hz, CH2), 3.02 (2H, t, J = 7.7 Hz, CH2), 6.29 (1H, d, J = 15.8 Hz, CH), 6.85 - 6.91 (2H, m, ArCH), 6.98 (1H, d, J = 7.6 Hz, ArCH), 7.20 - 7.29 (2H, m, ArCH), 7.46 (1H, d, J = 8.6, ArCH), 7.87 (2H, d, J = 16.0 Hz, ArCH and CH). 13C NMR (100 MHz; CDC13): δ 28.1, 30.9, 38.7, 81.0, 113.2, 113.4, 115.0, 115.2, 118.7, 122.4, 123.2, 124.0, 130.1, 133.5, 134.9, 137.5, 141.6, 143.0, 165.8, 170.4.

tert-butyl (E)-3-(4-bromo-3-(3-(2-fluorophenyl)propanamido)phenyl)acrylate (23e): To a solution of 21a (180 mg, 0.6 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-(2- fluorophenyl)propanoyl chloride (223 mg, 1.2 mmol) in DCM (2 mL) and NEt3 (0.2 mL, 3 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow solid (300 mg, 0.6 mmol, 90%).

Rf: 0.4 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 2.69 (2H, t, J = 7.4 Hz, CH2), 3.07 (2H, t, J = 7.7 Hz, CH2), 6.30 (1H, d, J = 15.8 Hz, CH), 6.99 - 7.07 (2H, m, ArCH), 7.16 - 7.30 (3H, m, ArCH), 7.47 (1H, d, J = 8.6 Hz, ArCH), 7.85 (1H, d, J = 2.4, ArCH), 7.88 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 25.0, 28.1, 37.6, 80.9, 115.2, 115.4, 118.7, 122.4, 123.3, 124.2, 124.2, 128.2, 128.3, 130.8, 130.8, 133.5, 134.9, 141.5, 165.8, 170.5.

tert-butyl (E)-3-(4-bromo-3-(3-(4-methoxyphenyl)propanamido)phenyl)acrylate (23f): To a solution of 21a (100 mg, 0.3 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-(4- methoxyphenyl)propanoyl chloride (200 mg, 1 mmol) in DCM (2 mL) and NEt3 (0.1 mL, 1 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (120 mg, 0.26 mmol, 76%).

Rf: 0.25 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 2.64 (2H, t, J = 7.3 Hz, CH2), 3.00 (2H, t, J = 7.4 Hz, CH2), 3.79 (3H, s, CH3), 6.31 (1H, d, J = 15.8 Hz, CH), 6.84 (2H, d, J = 8.6 Hz, ArCH), 7.14 (2H, d, J = 8.6 Hz, ArCH), 7.25 - 7.28 (1H, m, ArCH), 7.48 (1H, d, J = 8.6 Hz, ArCH), 7.82 (1H, d, J = 2.4, ArCH), 7.80 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 28.1, 30.5, 39.6, 55.2, 80.9, 114.0, 118.5, 119.4, 122.3, 123.3, 129.3, 132.3, 133.5, 134.9, 137.4, 141.5, 158.1, 165.7, 170.7.

(E)-3-(4-bromo-3-(3-(3-methoxyphenyl)propanamido)phenyl)acrylic acid (23g): To a solution of 21a (170 mg, 0.6 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-(3- methoxyphenyl)propanoyl chloride (300 mg, 1.5 mmol) in DCM (2 mL) and NEt3 (0.2 mL, 2 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (260 mg, 0.5 mmol, 90%).

Rf: 0.24 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (9H, s, C(CH3)3), 2.66 (2H, t, J = 7.4 Hz, CH2), 2.98 (2H, t, J = 7.7 Hz, CH2), 3.73 (3H, s, CH3), 6.27 (1H, d, J = 15.8 Hz, CH), 6.71 - 6.78 (3H, m, ArCH), 7.16 (1H, t, J = 8.4 Hz, ArCH), 7.28 (1H, d, J = 8.6 Hz, ArCH), 7.42 (1H, d, J = 8.6 Hz, ArCH), 7.84 (1H, s, ArCH), 7.86 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 28.1, 31.4, 38.9, 55.0, 80.9, 111.5, 114.1, 118.7, 119.4, 120.6, 122.5, 123.1, 129.6, 133.4, 134.7, 137.7, 141.6, 142.0, 159.7, 165.8, 171.0.

tert-butyl (E)-3-(4-bromo-3-(3-(2-methoxyphenyl)propanamido)phenyl)acrylate (23h): To a solution of 21a (230 mg, 0.8 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-(2- methoxyphenyl)propanoyl chloride (300 mg, 1.5 mmol) in DCM (2 mL) and NEt3 (0.2 mL, 2 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (330 mg, 0.7 mmol, 93%).

Rf: 0.22 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 2.67 (2H, t, J = 7.3 Hz, CH2), 3.04 (2H, t, J = 7.7 Hz, CH2), 3.80 (3H, s, CH3), 6.32 (1H, d, J = 15.8 Hz, CH), 6.85 - 6.92 (2H, m, ArCH), 7.16 - 7.28 (3H, m, ArCH), 7.47 (1H, d, J = 8.6 Hz, ArCH), 7.87 (1H, d, J = 2.4 Hz, ArCH), 7.90 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz; CDC13): δ 26.4, 28.1, 37.7, 55.3, 80.8, 110.3, 118.6, 119.2, 120.7, 122.3, 123.2, 127.8, 128.5, 130.1, 133.4, 134.9, 137.7, 141.6, 157.2, 165.7, 171.3.

tert-butyl (E)-3-(4-bromo-3-(3-(4-(tosyloxy)phenyl)propanamido)phenyl)acrylate (23i): To a solution of 21a (516 mg, 1.7 mmol) in dry DCM (10 mL) was added DMAP (26 mg, 0.2 mmol), a solution of 4-(3- chloro-3-oxopropyl)phenyl 4-methylbenzenesulfonate (630 mg, 2 mmol) in DCM (2 mL) and NEt3 (0.6 mL, 4.5 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a brown oil (600 mg, 1 mmol, 58%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.51 (9H, s, C(CH3)3), 2.41 (3H, s, CH3), 2.63 (2H, t, J = 7.6 Hz, CH2), 2.96 (2H, t, J = 7.6 Hz, CH2), 6.29 (1H, d, J = 15.8 Hz, CH), 6.80 (2H, d, J = 8.5 Hz, ArCH), 7.07 (2H, d, J = 8.5 Hz, ArCH), 7.24 - 7.29 (2H, m, ArCH), 7.42 (2H, d, J = 8.6 Hz, ArCH), 7.63 (2H, d, J = 8.3 Hz, ArCH), 7.86 (1H, d, J = 15.8, CH), 7.93 (1H, d, J = 2.4 Hz, ArCH), 8.17 (1H, br-s, NH). 13C NMR (100MHz, CDC13): 5 21.7, 28.1, 30.5, 38.6, 81.0, 115.5, 118.6, 119.3, 122.3, 122.4, 123.1, 128.3, 129.5, 129.8, 132.0, 133.4, 134.7, 137.7, 139.8, 141.6, 145.6, 147.8, 165.9, 170.6.

tert-butyl (E)-3-(4-bromo-3-(3-(3-(tosyloxy)phenyl)propanamido)phenyl)acrylate (23j): To a solution of 21a (490 mg, 1.6 mmol) in dry DCM (10 mL) was added DMAP (26 mg, 0.2 mmol), a solution of 3-(3- chloro-3-oxopropyl)phenyl 4-methylbenzenesulfonate (575 mg, 1.7 mmol) in DCM (2 mL) and NEt3 (0.4 mL, 3 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a brown oil (514 mg, 0.9 mmol, 56%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (9H, s, C(CH3)3), 2.42 (3H, s, CH3), 2.60 (2H, t, J = 7.5 Hz, CH2), 2.97 (2H, t, J = 7.6 Hz, CH2), 6.30 (1H, d, J = 15.8 Hz, CH), 6.70 (1H, d, J = 8.9 Hz, ArCH), 6.94 (1H, s, ArCH), 7.08 - 7.16 (2H, m, ArCH), 7.25 - 7.32 (3H, m, ArCH), 7.45 (1H, d, J = 8.6 Hz, ArCH), 7.63 (2H, d, J = 8.3 Hz, ArCH), 7.64 (1H, d, J = 8.3, CH), 7.87 (1H, d, J = 15.7 Hz, CH), 7.89 (1H, s, ArCH), 8.17 (1H, br-s, NH). 13C NMR (100MHz, CDC13): δ 21.7, 28.1, 30.8, 38.4, 80.9, 118.6, 119.4, 120.0, 122.1, 122.4, 123.2, 127.3, 128.3, 129.6, 129.8, 132.1, 133.5, 134.8, 137.6, 141.5, 142.6, 145.5, 149.6, 165.7, 170.3, 171.2.

(E)-N-(2-bromo-5-(2-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)vinyl)phenyl)-3-phenylpropanamide (24): To a solution of 21a (64 mg, 0.1 mmol) in dry DCM (5 mL) was added DMAP (2 mg, 0.01 mmol), a solution of 3-phenyl propanoyl chloride (50 mg, 0.3 mmol) in DCM (2 mL) and NEt3 (0.1 mL, 0.5 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (40 mg, 0.08 mmol, 87%). Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.33 (12H, s, CH3), 2.67 (2H, t, J = 7.4 Hz, CH2), 3.05 (2H, t, J = 7.6 Hz, CH2), 6.10 (1H, d, J = 18.2 Hz, CH), 7.22 - 7.34 (6H, m, ArCH), 7.47 (1H, d, J = 8.6 Hz, ArCH), 7.59 (1H, d, J = 2.2 Hz, ArCH), 7.65 (1H, d, J = 18.0 Hz, CH). 13C NMR (100 MHz; CDC13): δ 24.8, 31.4, 39.4, 83.5, 118.2, 118.7, 121.6, 126.4, 128.3, 128.6, 133.3, 137.2, 137.8, 140.4, 147.0, 170.3.

tert-butyl (E)-3-(4-(3-methylbut-2-en-l-yl)-3-(3-phenylpropanamido)phenyl)acrylate (25a): To a solution of 23a (200 mg, 0.4 mmol) in dry DMF (2 mL) was added CsC03 (230 mg, 0.7 mmol) and Pd(dppf)C12 (40 mg, 0.05 mmol). Prenyl boronic acid pinacol ester (140 μΐ., 0.62 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (80 mg, 0.2 mmol, 42 %).

Rf: 0.33 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.73 (3H, s, CH3), 1.74 (3H, s, CH3), 2.67 (2H, t, J = 7.4 Hz, CH2), 3.05 (2H, t, J = 7.4 Hz, CH2), 3.38 (2H, d, J = 6.4 Hz, CH2), 5.16 (1H, t, J = 5.6 Hz, CH), 6.27 (1H, d, J = 15.7 Hz, CH), 7.11 (1H, d, J = 8.0 Hz, Ar-H), 7.22 - 7.35 (5H, m, Ar-H), 7.57 (1H, s, Ar-H), 7.71 (1H, s, Ar-H), 7.84 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 28.2, 31.5, 31.5 39.2, 80.5, 117.9, 121.8, 122.4, 126.3, 128.3, 128.6, 130.1, 132.7, 133.8, 136.1, 137.1, 140.6, 140.8, 166.3, 170.6

tert-butyl (E)-3-(3-cinnamamido-4-(3-methylbut-2-en-l-yl)phenyl)acrylate (25b): To a solution of 23b (100 mg, 0.2 mmol) in dry DMF (4 mL) was added Cs2C03 (163 mg, 0.5 mmol) and Pd(dppf)C12 (25 mg, 0.03 mmol). Prenyl boronic acid pinacol ester (111 μΐ., 0.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (80 mg, 0.2 mmol, 83%).

Rf: 0.5 (Hexane:EtOAc, 4:1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.74 (3H, s, CH3), 3.39 (2H, d, J = 6.9 Hz, CH2), 5.16 (1H, t, J = 7.1 Hz, CH), 6.31 (1H, d, J = 15.7 Hz, CH), 6.64 (1H, d, J = 15.5 Hz, CH), 7.15 (1H, d, J = 8.2 Hz, ArCH), 7.31 - 7.38 (3H, m, ArCH), 7.47 - 7.58 (3H, m, ArCH), 7.76 (1H, d, J = 15.5 Hz, CH), 7.86 (1H, d, J = 15.8 Hz, CH), 7.91 (1H, s, ArCH). 13C NMR (100MHz , CDC13): δ 17.9, 25.7, 28.2, 31.6, 80.5, 117.9, 120.8, 121.6, 122.4, 127.9, 128.8, 129.9, 130.2, 132.7, 133.8, 134.5, 136.5, 137.2, 140.8, 142.3, 164.2, 166.4

tert-butyl (E)-3-(3-(3-(4-fluorophenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylate (25c): To a solution of 23c (150 mg, 0.3 mmol) in dry DMF (2 mL) was added Cs2C03 (230 mg, 0.7 mmol) and Pd(dppf)C12 (40 mg, 0.05 mmol). Prenyl boronic acid pinacol ester (100 uL, 0.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (66 mg, 0.15 mmol, 50%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.50 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.74 (3H, s, CH3), 2.63 (2H, t, J = 7.4 Hz, CH2), 3.02 (2H, t, J = 7.4 Hz, CH2), 3.38 (2H, d, J = 7.0 Hz, CH2), 5.14 (1H, t, J = 7.0 Hz, CH), 6.27 (1H, d, J = 15.7 Hz, CH), 6.96 (2H, t, J = 8.6 Hz, ArCH), 7.12 (1H, d, J = 8.1 Hz, ArCH), 7.18 (2H, t, J = 8.4 Hz, ArCH), 7.34 (1H, dd, Jl = 2.1 Hz, J2 = 8.2 Hz, ArCH), 7.45 (1H, s, NH), 7.72 (1H, d, J = 2.0, ArCH), 7.84 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 28.2, 30.6, 31.5, 39.3, 80.5, 115.2, 115.4, 117.9, 121.5, 121.9, 122.4, 129.7, 129.8, 130.1, 132.8, 133.8, 136.0, 136.2, 137.2, 140.7, 166.2, 170.2.

tert-butyl (E)-3-(3-(3-(3-fluorophenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylate (25d): To a solution of 23d (400 mg, 0.9 mmol) in dry DMF (10 mL) was added Cs2C03 (530 mg, 1.8 mmol) and Pd(dppf)C12 (104 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (260 uL, 1.1 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (150 mg, 0.4 mmol, 44%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.74 (3H, s, CH3), 2.66 (2H, t, J = 7.2 Hz, CH2), 3.04 (2H, t, J = 7.4 Hz, CH2), 3.37 (2H, d, J = 6.9 Hz, CH2), 5.15 (1H, t, J = 7.0 Hz, CH), 6.26 (1H, d, J = 15.7 Hz, CH), 6.87 - 6.94 (2H, m, ArCH), 6.99 (1H, d, J = 7.6 Hz, ArCH), 7.21 - 7.28 (1H, m, ArCH), 7.35 (1H, dd, Jl = 1.9 Hz, J2 = 8.2 Hz, ArCH), 7.58 (1H, s, NH), 7.71 (1H, d, J = 1.8, ArCH), 7.83 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 28.2, 31.0, 31.5, 38.7, 80.5, 113.1, 113.3, 115.1, 115.3, 117.9, 121.5, 121.9, 122.4, 124.0, 124.0, 130.0, 130.1, 140.7, 143.1, 161.6, 164.1, 166.3, 170.2.

tert-butyl (E)-3-(3-(3-(2-fluorophenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylate (25e): To a solution of 23e (300 mg, 0.6 mmol) in dry DMF (10 mL) was added Cs2C03 (460 mg, 1.4 mmol) and Pd(dppf)C12 (80 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (200 uL, 0.8 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (200 mg, 0.4 mmol, 69%).

Rf: 0.4 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 1.71 (3H, s, CH3), 1.73 (3H, s, CH3), 2.67 (2H, t, J = 7.4 Hz, CH2), 3.06 (2H, t, J = 7.6 Hz, CH2), 3.36 (2H, d, J = 6.9 Hz, CH2), 5.14 (1H, t, J = 7.0 Hz, CH), 6.25 (1H, d, J = 15.7 Hz, CH), 6.98 - 7.05 (2H, m, ArCH), 7.09 (1H, d, J = 8.9 Hz, ArCH), 7.15 - 7.24 (2H, m, ArCH), 7.35 (1H, dd, Jl = 1.8 Hz, J2 = 8.2 Hz, ArCH), 7.71 (1H, d, J = 1.8, ArCH), 7.79 (1H, s, NH), 7.82 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.1, 25.7, 28.2, 31.5, 37.5, 80.5, 115.1, 115.3, 118.2, 121.8, 122.5, 124.1, 127.3, 128.1, 130.1, 130.8, 132.2, 133.7, 136.2, 137.1, 140.8, 159.8, 162.3, 166.3, 170.4.

tert-butyl (E)-3-(3-(3-(4-methoxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylate (25f): To a solution of 23f (120 mg, 0.3 mmol) in dry DMF (3 mL) was added Cs2C03 (166 mg, 0.5 mmol) and Pd(dppf)C12 (22 mg, 0.03 mmol). Prenyl boronic acid pinacol ester (110 μΐ., 0.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (50 mg, 0.1 mmol, 37%).

Rf: 0.25 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.74 (3H, s, CH3), 2.63 (2H, t, J = 7.4 Hz, CH2), 2.99 (2H, t, J = 7.6 Hz, CH2), 3.38 (2H, d, J = 7.0 Hz, CH2), 3.78 (3H, s, CH3), 5.15 (1H, t, J = 7.0 Hz, CH), 6.26 (1H, d, J = 15.7 Hz, CH), 6.83 (2H, d, J = 8.5 Hz, ArCH), 7.10 - 7.15 (3H, m, ArCH), 7.35 (1H, d, J = 9.4 Hz, ArCH), 7.49 (1H, s, NH), 7.69 (1H, s, ArCH), 7.84 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 28.2, 30.7, 31.5, 39.6, 55.2, 80.5, 114.0, 117.9, 121.5, 121.8, 122.4, 129.3, 130.1, 132.6, 132.7, 133.7, 136.1, 137.1, 140.8, 158.1, 166.3, 170.7.

tert-butyl (E)-3-(3-(3-(3-methoxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylate (25g): To a solution of 23g (200 mg, 0.6 mmol) in dry DMF (10 mL) was added Cs2C03 (460 mg, 1.4 mmol) and Pd(dppf)C12 (80 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (200 μΐ., 0.8 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (240 mg, 0.5 mmol, 81%).

Rf: 0.43 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.74 (3H, s, CH3), 2.66 (2H, t, J = 7.4 Hz, CH2), 3.02 (2H, t, J = 7.6 Hz, CH2), 3.37 (2H, d, J = 6.2 Hz, CH2), 3.76 (3H, s, CH3), 5.15 (1H, t, J = 7.0 Hz, CH), 6.26 (1H, d, J = 15.7 Hz, CH), 6.75 - 6.82 (3H, m, ArCH), 7.11 (1H, d, J = 8.3 Hz, ArCH), 7.20 (1H, t, J = 7.7 Hz, ArCH), 7.36 (1H, dd, Jl = 2.0 Hz, J2 = 8.2 Hz, ArCH), 7.60 (1H, s, NH), 7.69 (1H, d, J = 2.0 Hz, ArCH), 7.83 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 28.2, 31.5, 31.6, 55.1, 80.5, 111.6, 114.1, 117.9, 120.7, 121.6, 121.8, 122.5, 129.6, 130.1, 132.7, 133.7, 136.1, 137.1, 140.8, 142.2, 159.7, 166.3, 170.6.

tert-butyl (E)-3-(3-(3-(2-methoxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylate (25h): To a solution of 23h (330 mg, 0.7 mmol) in dry DMF (10 mL) was added Cs2C03 (460 mg, 1.4 mmol) and Pd(dppf)C12 (80 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (200 μΐ., 0.8 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (290 mg, 0.6 mmol, 89%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.74 (3H, s, CH3), 2.66 (2H, t, J = 7.5 Hz, CH2), 3.04 (2H, t, J = 7.6 Hz, CH2), 3.37 (2H, d, J = 6.9 Hz, CH2), 3.80 (3H, s, CH3), 5.15 (1H, t, J = 7.0 Hz, CH), 6.27 (1H, d, J = 15.8 Hz, CH), 6.86 (2H, q, J = 6.5 Hz, ArCH), 7.09 (1H, d, J = 8.2 Hz, ArCH), 7.15 - 7.22 (2H, m, ArCH), 7.36 (1H, dd, Jl = 1.9 Hz, J2 = 8.2 Hz, ArCH), 7.74 (1H, d, J = 1.8 Hz, ArCH), 7.79 (1H, s, NH), 7.84 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 25.7, 26.5, 28.2, 31.5, 37.6, 55.2, 80.4, 110.3, 117.9, 120.6, 121.5, 121.7, 122.5, 127.6, 128.8, 130.0, 130.0, 132.6, 133.6, 136.4, 136.9, 140.8, 157.3, 166.3, 171.3.

tert-butyl (E)-3 -(4-(3-methy lbut-2-en- 1 -y l)-3 -(3 -(4-(tosy loxy)pheny l)propanamido)pheny l)acry late (25i) : To a solution of 23i (600 mg, 1 mmol) in dry DMF (5 mL) was added Cs2C03 (490 mg, 1.5 mmol) and Pd(dppf)C12 (80 mg, 0.1 mmol). Prenyl boronic acid pinacol ester (340 μΐ., 1.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (400 mg, 0.7 mmol, 68%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (9H, s, C(CH3)3), 1.70 (3H, s, CH3), 1.72 (3H, s, CH3), 2.41 (3H, s, CH3), 2.62 (2H, t, J = 7.5 Hz, CH2), 2.98 (2H, t, J = 7.5 Hz, CH2), 3.36 (2H, d, J = 6.9 Hz, CH2), 5.13 (1H, t, J = 7.0 Hz, CH), 6.26 (1H, d, J = 15.7 Hz, CH), 6.83 (2H, d, J = 8.5 Hz, ArCH), 7.10 (2H, d, J = 8.4 Hz, ArCH), 7.25 (2H, d, J = 8.0 Hz, ArCH), 7.33 (1H, dd, Jl = 8.2 Hz, J2 = 2.1 Hz, ArCH), 7.64 (2H, d, J = 8.3 Hz, ArCH), 7.77 (1H, d, J = 2.0 Hz, ArCH), 7.82 (1H, s, ArCH), 7.83 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; CDC13): δ 17.9, 24.8, 25.6, 28.1, 30.7, 31.5, 38.7, 80.5, 117.8, 121.4, 121.8, 122.3, 122.4, 128.4, 129.5, 129.7, 130.1, 132.2, 133.7, 136.2, 137.1, 139.8, 140.8, 145.4, 147.9, 166.3, 170.3.

tert-buty 1 (E)-3 -(4-(3-methy lbut-2-en- 1 -y l)-3 -(3 -(3-(tosy loxy)pheny l)propanamido)pheny l)acry late (25j) : To a solution of 23j (270 mg, 0.4 mmol) in dry DMF (4 mL) was added Cs2C03 (211 mg, 0.6 mmol) and Pd(dppf)C12 (32 mg, 0.04 mmol). Prenyl boronic acid pinacol ester (110 μΐ., 0.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (290 mg, 0.7 mmol, 50%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.51 (9H, s, C(CH3)3), 1.69 (3H, s, CH3), 1.72 (3H, s, CH3), 2.40 (3H, s, CH3), 2.58 (2H, t, J = 7.5 Hz, CH2), 2.95 (2H, t, J = 7.5 Hz, CH2), 3.37 (2H, d, J = 6.9 Hz, CH2), 5.13 (1H, t, J = 7.0 Hz, CH), 6.24 (1H, d, J = 15.7 Hz, CH), 6.72 (1H, d, J = 7.8 Hz, ArCH), 6.91 (1H, s, ArCH), 7.07 - 7.15 (3H, m, ArCH), 7.24 (2H, d, J = 8.0 Hz, ArCH), 7.36 (1H, dd, Jl = 8.2 Hz, J2 = 2.1 Hz, ArCH), 7.64 (2H, d, J = 8.3 Hz, ArCH), 7.75 (1H, d, J = 2.0 Hz, ArCH), 7.82 (1H, d, J = 15.8 Hz, CH), 7.92 (1H, s, NH). 13C NMR (100 MHz; CDC13): δ 17.9, 21.6, 25.6, 28.1, 30.9, 31.5, 38.4, 80.4, 117.8, 119.9, 121.5, 121.8, 122.1, 122.5, 127.3, 128.3, 129.6, 129.7, 130.1, 132.6, 136.3, 137.0, 140.7, 142.8, 145.4, 149.6, 166.2, 170.2.

(E)-3-(4-(3-methylbut-2-en-l-yl)-3-(3-phenylpropanamido)phenyl)acrylic acid (26a): To a solution of 25a (80 mg, 0.2 mmol) in dry toluene (6 mL) was added silica gel (3 mL) and the suspension stirred at reflux overnight. The reaction was allowed to cool and the mixture filtered, washing with 20 % MeOH in DCM, and the solvent evaporated in vacuo to provide the title compound as a white solid (18.7 mg, 0.05 mmol, 27 %).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz, MeOD): δ 1.72 (3H, s, CH3), 1.79 (3H, s, CH3), 2.66 (2H, t, J = 7.4 Hz, CH2), 3.01 (2H, t, J = 7.4 Hz, CH2), 3.43 (2H, d, J = 6.6 Hz, CH2), 5.16 (1H, t, J = 5.9 Hz, CH), 6.33 (1H, d, J = 15.7 Hz, CH), 7.16 - 7.30 (6H, m, Ar-H), 7.46 (1H, d, J = 8.0 Hz, Ar-H), 7.80 (1H, s, Ar-H), 7.96 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz, MeOD): δ 16.6, 24.4, 31.3, 31.3, 38.4, 117.5, 119.2, 121.7, 122.6, 125.8, 128.1, 129.9, 132.0, 133.2, 136.9, 137.0, 140.7, 142.3, 168.8, 172.2. m/z (ESI): 364.2 [M + H]+ (100%), 386.3 [M + Na]+ (17.5%). HRMS-ESI: (m/z) calculated for C23H25N03, 362.1762; found, 362.1761.

(E)-3-(3-cinnamamido-4-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (26b): Compound 25b (80 mg, 0.2 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1 : 1) provided the title compound as a white soild (20 mg, 0.05 mmol, 30%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz, MeOD): δ 1.74 (3H, s, CH3), 1.80 (3H, s, CH3), 3.47 (2H, d, J = 7.0 Hz, CH2), 5.19 (1H, t, J = 7.1 Hz, CH), 6.39 (1H, d, J = 15.8 Hz, CH), 6.81 (1H, d, J = 15.6 Hz, CH), 7.23 (1H, d, J = 8.3 Hz, ArCH), 7.39 - 7.46 (3H, m, ArCH), 7.61 - 7.64 (3H, m, ArCH), 7.69 (1H, d, J = 15.6 Hz, CH), 8.0 (1H, d, J = 15.7 Hz, CH), 8.0 (1H, d, J = 2.1 Hz, ArCH). 13C NMR (100MHz, MeOD): δ 16.6, 24.5, 31.4, 99.9, 117.4, 119.5, 120.7, 121.6, 122.6, 127.5, 128.6, 129.6, 130.0, 132.1, 133.4, 134.8, 137.1, 137.1, 141.5, 142.2, 165.2

(E)-3-(3-(3-(4-fluorophenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (26c): Compound 25c (66 mg, 0.15 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a white soild (50 mg, 0.13 mmol, 87%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.73 (3H, s, CH3), 1.79 (3H, s, CH3), 2.66 (2H, t, J = 7.4 Hz, CH2), 3.00 (2H, t, J = 7.4 Hz, CH2), 3.4 (2H, d, J = 7.4 Hz, CH2), 5.16 (1H, t, J = 7.8 Hz, CH), 6.33 (1H, d, J = 17.5 Hz, CH), 7.00 (2H, t, J = 8.6 Hz, ArCH), 7.18 (1H, d, J = 8.3 Hz, ArCH), 7.27 (2H, dd, Jl = 3.2 Hz, J2 = 5.5 Hz, ArCH), 7.46 (1H, dd, Jl = 2.1 Hz, J2 = 8.2 Hz, ArCH), 7.81 (1H, d, J = 2.0, ArCH), 7.96 (1H, d, J = 17.3 Hz, CH). 13C NMR (100 MHz; MeOD): δ 24.4, 29.2, 30.4, 31.3, 38.4, 114.5, 114.7, 117.5, 121.6, 122.6, 129.6, 129.7, 129.9, 132.2, 133.3, 136.6, 136.9, 136.9, 142.1, 162.7, 172.0.

(E)-3 -(3 -(3-(3 -fluoropheny l)propanamido)-4-(3 -methy lbut-2-en- 1 -y l)pheny l)acry lie acid (26d) : Compound 25d (150 mg, 0.4 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a white soild (120 mg, 0.32 mmol, 80%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.72 (3H, s, CH3), 1.78 (3H, s, CH3), 2.68 (2H, t, J = 7.3 Hz, CH2), 3.02 (2H, t, J = 7.4 Hz, CH2), 3.41 (2H, d, J = 6.9 Hz, CH2), 5.15 (1H, t, J = 7.0 Hz, CH), 6.33 (1H, d, J = 15.7 Hz, CH), 6.92 (1H, t, J = 8.2 Hz, ArCH), 7.02 (1H, d, J = 9.8 Hz, ArCH), 7.08 (1H, d, J = 7.6 Hz, ArCH), 7.17 (1H, d, J = 8.3 Hz, ArCH), 7.29 (1H, q, J = 7.9 Hz, ArCH), 7.46 (1H, dd, Jl = 2.1 Hz, J2 = 8.2 Hz, ArCH), 7.79 (1H, d, J = 2.1, ArCH), 7.95 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 24.4, 30.9, 31.3, 37.9, 112.4, 112.6, 114.6, 114.8, 117.5, 121.7, 122.6, 123.9, 129.7, 129.8, 129.9, 132.0, 133.3, 136.8, 137.0, 161.7, 164.1, 171.9.

(E)-3-(3-(3-(2-fluorophenyl)propanamido)-4-(3-methylbut-2-en- 1 -yl)phenyl)acrylic acid (26e) : Compound 25e (200 mg, 0.4 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a white soild (130 mg, 0.34 mmol, 85%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.72 (3H, s, CH3), 1.78 (3H, s, CH3), 2.68 (2H, t, J = 7.4 Hz, CH2), 3.05 (2H, t, J = 7.6 Hz, CH2), 3.41 (2H, d, J = 6.9 Hz, CH2), 5.14 (1H, t, J = 7.0 Hz, CH), 6.32 (1H, d, J = 15.7 Hz, CH), 7.03 - 7.11 (2H, m, ArCH), 7.16 (1H, d, J = 8.3 Hz, ArCH), 7.20 - 7.25 (1H, m, ArCH), 7.30 (1H, t, J = 7.6 Hz, ArCH), 7.45 (1H, dd, Jl = 1.8 Hz, J2 = 8.2 Hz, ArCH), 7.80 (1H, d, J = 2.1, ArCH), 7.96 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 24.4, 24.6, 31.3, 36.7, 114.6, 114.8, 117.6, 119.2, 121.8, 122.6, 123.9, 127.9, 129.9, 130.5, 132.0, 133.2, 137.0, 142.3, 159.8, 1652.3, 168.9, 171.9.

(E)-3-(3-(3-(4-methoxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (26f): Compound 25f (50 mg, 0.1 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a white soild (25 mg, 0.06 mmol, 53%).

Rf: 0.25 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.73 (3H, s, CH3), 1.79 (3H, s, CH3), 2.64 (2H, t, J = 7.4 Hz, CH2), 2.95 (2H, t, J = 7.6 Hz, CH2), 3.44 (2H, d, J = 7.2 Hz, CH2), 3.76 (3H, s, CH3), 5.15 (1H, t, J = 8.4 Hz, CH), 6.33 (1H, d, J = 15.7 Hz, CH), 6.85 (2H, d, J = 8.6 Hz, ArCH), 7.18 (3H, d, J = 8.4 Hz, ArCH), 7.46 (1H, d, Jl = 2.3 Hz, J2 = 8.2 Hz, ArCH), 7.79 (1H, d, J = 2.1 Hz, ArCH), 7.96 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.5, 24.4, 30.5, 31.3, 38.7, 54.2, 113.4, 117.6, 119.4, 121.7, 122.6, 128.9, 129.9, 132.0, 132.6, 133.2, 136.9, 136.9, 142.2, 157.8, 158.2, 172.4.

(E)-3-(3-(3-(3-methoxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acry acid (26g): Compound 25g (240 mg, 0.5 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a white soild (62 mg, 0.16 mmol, 31%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.73 (3H, s, CH3), 1.79 (3H, s, CH3), 2.67 (2H, t, J = 7.4 Hz, CH2), 2.99 (2H, t, J = 7.6 Hz, CH2), 3.43 (2H, d, J = 6.7 Hz, CH2), 3.76 (3H, s, CH3), 5.16 (1H, t, J = 7.0 Hz, CH), 6.33 (1H, d, J = 15.7 Hz, CH), 6.76 (1H, dd, Jl = 2.5 Hz, J2 = 7.9 Hz, ArCH), 6.83 - 6.85 (2H, m, ArCH), 7.16 - 7.22 (2H, m, ArCH), 7.46 (1H, dd, Jl = 2.2 Hz, J2 = 8.2 Hz, ArCH), 7.80 (1H, d, J = 2.1 Hz, ArCH), 7.97 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 24.4, 31.3, 31.4, 38.3, 5.1, 111.3, 113.6, 117.6, 129.3, 120.3, 121.8, 122.6, 129.0, 129.9, 132.0, 133.2, 136.9, 137.0, 142.2, 142.3, 159.8, 168.8, 172.3.

(E)-3-(3-(3-(2-methoxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (26h): Compound 25h (290 mg, 0.6 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a white soild (110 mg, 0.3 mmol, 50%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.73 (3H, s, CH3), 1.79 (3H, s, CH3), 2.64 (2H, t, J = 7.5 Hz, CH2), 3.00 (2H, t, J = 7.6 Hz, CH2), 3.43 (2H, d, J = 6.9 Hz, CH2), 3.84 (3H, s, CH3), 5.15 (1H, t, J = 7.0 Hz, CH), 6.33 (1H, d, J = 15.8 Hz, CH), 6.86 (1H, t, J = 7.5 Hz, ArCH), 6.93 (1H, d, J = 7.9 Hz, ArCH), 7.16 - 7.21 (3H, m, ArCH), 7.46 (1H, dd, Jl = 2.2 Hz, J2 = 8.3 Hz, ArCH), 7.81 (1H, d, J = 2.1 Hz, ArCH), 7.97 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 24.4, 26.3, 31.3, 36.8, 54.2, 109.9, 117.7, 119.1, 120.0, 121.8, 122.6, 127.3, 128.6, 129.5, 129.9, 132.0, 133.1, 136.9, 137.0, 142.4, 157.4, 168.7, 172.7.

(E)-3-(4-(3-methylbut-2-en-l-yl)-3-(3-(4-(tosyloxy)phenyl)propanamido)phenyl)acrylic acid (26i): Compound 25i (400 mg, 0.7 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a white soild (104 mg, 0.2 mmol, 28%).

Rf: 0.4 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; MeOD): δ 1.72 (3H, s, CH3), 1.79 (3H, s, CH3), 2.39 (3H, s, CH3), 2.65 (2H, t, J = 7.5 Hz, CH2), 2.99 (2H, t, J = 7.5 Hz, CH2), 3.45 (2H, d, J = 6.8 Hz, CH2), 5.16 (1H, t, J = 7.0 Hz, CH), 6.34 (1H, d, J = 15.7 Hz, CH), 6.88 (2H, d, J = 8.5 Hz, ArCH), 7.18 - 7.31 (5H, m, ArCH), 7.44 (1H, d, J = 8.3 Hz, ArCH), 7.59 (2H, d, J = 8.2 Hz, ArCH), 7.82 (1H, d, J = 1.8 Hz, ArCH), 7.97 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.5, 20.1, 24.4, 30.5, 31.3 38.0, 117.4, 121.6, 122.0, 122.6, 128.2, 129.3, 129.4, 129.9, 132.0, 132.1, 133.3, 136.9, 137.0, 140.0, 142.0, 145.6, 148.1.

(E)-3-(4-(3-methylbut-2-en-l-yl)-3-(3-(3-(tosyloxy)phenyl)propanamido)phenyl)acrylic acid (26j): Compound 25j (290 mg, 0.5 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (DCM:MeOH = 20: 1, 10: 1) provided the title compound as a white soild (110 mg, 0.2 mmol, 41%).

Rf: 0.2 (EtOAC). 1H NMR (400 MHz; MeOD): δ 1.70 (3H, s, CH3), 1.76 (3H, s, CH3), 2.39 (3H, s, CH3), 2.61 (2H, t, J = 7.5 Hz, CH2), 2.94 (2H, t, J = 7.5 Hz, CH2), 3.40 (2H, d, J = 6.9 Hz, CH2), 5.13 (1H, t, J = 7.0 Hz, CH), 6.32 (1H, d, J = 15.7 Hz, CH), 6.75 (1H, d, J = 7.3 Hz, ArCH), 6.95 (1H, s, ArCH), 7.14 - 7.22 (3H, m, ArCH), 7.30 (2H, d, J = 8.0 Hz, ArCH), 7.47 (1H, dd, Jl = 8.2 Hz, J2 = 2.1 Hz, ArCH), 7.61 (2H, d, J = 8.3 Hz, ArCH), 7.81 (1H, d, J = 2.1 Hz, ArCH), 7.95 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.6, 20.2, 24.5, 30.7, 31.3, 37.7, 117.6, 119.4, 119.6, 121.7, 121.9, 122.6, 127.0, 128.2, 129.2, 129.5, 129.9, 132.0, 132.1, 133.2, 136.9, 137.0, 142.2, 143.0, 145.6, 149.7, 168.8, 171.6.

(E)-3-(3-(3-(4-hydroxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (26k): Compound 26i (80 mg, 0.15 mmol) was dissolved in MeOH (4 mL) and refluxed with 1M NaOH (2 mL) overnight. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a white soild (50 mg, 0.12 mmol, 84%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; MeOD): δ 1.73 (3H, s, CH3), 1.79 (3H, s, CH3), 2.62 (2H, t, J = 7.5 Hz, CH2), 2.92 (2H, t, J = 7.5 Hz, CH2), 3.44 (2H, d, J = 7.4 Hz, CH2), 5.16 (1H, t, J = 7.0 Hz, CH), 6.33 (1H, d, J = 15.7 Hz, CH), 6.71 (2H, d, J = 8.5 Hz, ArCH), 7.08 (2H, d, J = 8.5 Hz, ArCH), 7.17 (1H, d, J = 8.3 Hz, ArCH), 7.46 (1H, d, Jl = 2.1 Hz, J2 = 8.2 Hz, ArCH), 7.81 (1H, d, J = 2.1 Hz, ArCH), 7.97 (1H, d, J = 15.8 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.5, 24.4, 30.6, 31.3, 38.8, 114.8, 117.6, 121.7, 122.6, 128.9, 129.8, 131.4, 132.2, 133.2, 136.9, 142.2, 155.3, 168.9, 172.5.

(E)-3-(3-(3-(3-hydroxyphenyl)propanamido)-4-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (261): Compound 26j (15 mg, 0.02 mmol) was dissolved in MeOH (2 mL) and refluxed with 1M NaOH (2 mL) overnight. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a white soild (8 mg, 0.02 mmol, 90%).

Rf: 0.2 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; MeOD): δ 1.73 (3H, s, CH3), 1.79 (3H, s, CH3), 2.65 (2H, t, J = 7.5 Hz, CH2), 2.94 (2H, t, J = 7.5 Hz, CH2), 3.44 (2H, d, J = 7.0 Hz, CH2), 5.17 (1H, t, J = 7.0 Hz, CH), 6.35 (1H, d, J = 15.6 Hz, CH), 6.63 (1H, d, Jl = 2.1 Hz, J2 = 8.2 Hz, ArCH), 6.71 - 6.74 (2H, m, ArCH), 7.10 (1H, t, J = 7.4 Hz, ArCH), 7.17 (1H, d, J = 8.3 Hz, ArCH), 7.47 (1H, d, Jl = 2.1 Hz, J2 = 8.4 Hz, ArCH), 7.81 (1H, d, J = 2.4 Hz, ArCH), 7.95 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz; MeOD): δ 16.5, 24.4, 31.3, 31.3, 99.9, 122.7, 114.8, 117.6, 119.1, 121.7, 122.6, 129.0, 129.8, 132.0, 133.3, 136.9, 142.2, 157.1, 172.3.

tert-butyl (E)-3-(3'-(¾ydroxymethyl)-2-(3-phenylpropanamido)-[l,r-biphenyl]-4-yl)acrylate (27): To a solution of (23a) (100 mg, 0.2 mmol) in dry DMF (4 mL) was added Cs2C03 (166 mg, 0.5 mmol) and Pd(dppf)C12 (22 mg, 0.03 mmol). (3-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl)methanol (110 μΐ., 0.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9:1, 4: 1) provided the title compound as a transparent oil (70 mg, 0.15 mmol, 66%).

Rf: 0.5 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.47 (9H, s, C(CH3)3), 2.69 (2H, t, J = 7.6 Hz, CH2), 3.07 (2H, t, J = 7.6 Hz, CH2), 4.67 (2H, s, CH2), 6.29 (1H, d, J = 15.8 Hz, CH), 7.13 - 7.39 (12H, m, ArCH), 7.56 (1H, d, J = 15.9 Hz, CH), 7.79 (1H, s, NH), 7.85 (1H, s, OH). 13C NMR (100 MHz , CDC13): δ 28.1, 31.5, 39.2, 65.0, 80.6, 117.6, 121.1, 121.4, 126.1, 126.4, 128.3, 128.4, 128.6, 129.0, 130.8, 132.9, 137.2, 138.7, 139.5, 140.5, 141.0, 142.1, 166.5, 170.9.

(E)-3-(3'-(hydroxymethyl)-2-(3-phenylpropanamido)-[l,l'-biphenyl]-4-yl)acrylic acid (28): Compound 27 (70 mg, 0.15 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (DCM:MeOH = 20: 1, 10: 1) provided the title compound as a white soild (27 mg, 0.06 mmol, 45%).

Rf: 0.3 (DCM:MeOH, 10: 1).1H NMR (400MHz , MeOD): δ 2.72 (2H, t, J = 7.6 Hz, CH2), 3.04 (2H, t, J = 7.6 Hz, CH2), 4.68 (2H, s, CH2), 6.41 (1H, d, J = 15.8 Hz, CH), 7.18 - 7.23 (2H, m, ArCH), 7.28 - 7.32 (6H, m, ArCH), 7.39 - 7.45 (2H, m, ArCH), 7.62 - 7.66 (2H, m, ArCH and CH), 7.99 (1H, d, J = 2.0 Hz, ArCH). 13C NMR (100 MHz , MeOD): δ 31.3, 38.5, 63.6, 117.3, 119.5, 121.3, 125.6, 125.8, 127.9, 128.0, 128.1, 128.5, 130.5, 132.6, 138.1, 138.6, 139.7, 140.7, 141.6, 143.2, 172.4.

N-(4-bromo-2-iodophenyl)-3-phenylpropanamide (30): To a solution of 4-bromo-2-iodo aniline (300 mg, 1 mmol) in dry DCM (5 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-phenylpropanoyl chloride (400 mg, 2 mmol) in DCM (2 mL) and NEt3 (0.4 mL, 3 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (300 mg, 0.7 mmol, 69%).

Rf: 0.5 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz, CDC13): δ 2.76 (2H, t, J = 7.4 Hz, CH2), 3.09 (2H, t, J = 7.8 Hz, CH2), 7.21 - 7.34 (5H, m, ArCH), 7.45 (1H, dd, Jl = 8.6 Hz, J2 = 2.2 Hz ArCH), 7.89 (1H, d, J = 2.2 Hz, ArCH), 8.14 (1H, d, J = 8.8 Hz, ArCH). 13C NMR (100 MHz, CDC13): δ 31.3, 39.6, 126.5, 128.3, 128.7, 132.2, 137.3 140.1, 140.4.

tert-butyl (E)-3-(5-bromo-2-(3-phenylpropanamido)phenyl)acrylate (31): To a solution of 30 (300 mg, 0.7 mmol) in dry toluene (10 mL) was added PPh3 (26 mg, 0.1 mmol) and Pd(OAc)2 (12 mg, 0.05 mmol). tert-butyl acrylate (160 μΕ, 1 mmol) and NEt3 (280 μΕ, 2 mmol) were added and the reaction was refluxed overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc gradient = 9: 1, 4: 1, 2: 1, 1 : 1, 0: 1) provided the title compound as a white solid (210 mg, 0.5 mmol, 70 %).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz , CDC13): δ 1.53 (9H, s, C(CH3)3), 2.71 (2H, t, J = 7.6 Hz, CH2), 3.05 (2H, t, J = 7.3 Hz, CH2), 6.27 (1H, d, J = 15.7 Hz, CH), 7.20 - 7.24 (3H, m, ArCH), 7.30 - 7.35 (2H, m, ArCH), 7.40 (1H, dd, Jl = 8.6 Hz, J2 = 2.2 Hz ArCH), 7.51 - 7.56 (2H, m, ArCH and CH), 7.60 (1H, s, ArCH). 13C NMR (100 MHz, CDC13): δ 28.1, 31.4, 38.8, 81.1, 121.4, 123.7, 126.3, 126.4, 128.3, 128.3, 128.6, 128.6, 129.6, 131.8, 133.1, 134.6, 136.6, 140.3, 165.6, 171.1.

tert-butyl (E)-3-(5-(3-methylbut-2-en-l-yl)-2-(3-phenylpropanamido)phenyl)acrylate (32a): To a solution of 31 (100 mg, 0.2 mmol) in dry DMF (3 mL) was added Cs2C03 (160 mg, 0.5 mmol) and Pd(dppf)C12 (25 mg, 0.03 mmol). Prenyl boronic acid pinacol ester (100 μΐ., 0.4 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (30 mg, 0.07 mmol, 68%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400MHz , CDC13): δ 1.52 (9H, s, C(CH3)3), 1.73 (3H, s, CH3), 1.77 (3H, s, CH3), 2.73 (2H, t, J = 7.6 Hz, CH2), 3.08 (2H, t, J = 7.4 Hz, CH2), 3.32 (2H, d, J = 6.8 Hz, CH2), 5.29 (1H, t, J = 7.3 Hz, CH), 6.31 (1H, d, J = 15.7 Hz, CH), 7.16 - 7.26 (4H, m, ArCH), 7.30 - 7.34 (3H, m, ArCH), 7.54 (1H, d, J = 8.2 Hz, ArCH), 7.64 (1H, d, J = 15.7 Hz, CH). 13C NMR (100 MHz, CDC13): δ 17.8, 25.7, 28.2, 33.8, 80.8, 119.7, 120.1, 122.2, 122.5, 125.3, 126.6, 128.3, 128.4, 128.6, 130.6, 133.3, 138.3, 140.5, 166.0, 170.9.

tert-butyl (E)-3-(3'-(hydroxymethyl)-4-(3-phenylpropanamido)-[l,l'-biphenyl]-3-yl)acrylate (32b): To a solution of 31 (70 mg, 0.1 mmol) in dry DMF (3 mL) was added Cs2C03 (70 mg, 0.2 mmol) and Pd(dppf)C12 (10 mg, 0.01 mmol). (3-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl)methanol (50 μΐ., 0.2 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9:1, 4: 1) provided the title compound as a transparent oil (20 mg, 0.04 mmol, 27%). Rf: 0.5 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz , CDC13): δ 1.55 (9H, s, C(CH3)3), 2.75 (2H, t, J = 7.6 Hz, CH2), 3.09 (2H, t, J = 7.4 Hz, CH2), 4.75 (2H, s, CH2), 6.32 (1H, d, J = 15.8 Hz, CH), 7.23 - 7.50 (10H, m, ArCH and CH), 7.63 - 7.67 (2H, m, ArCH), 7.77 (1H, d, J = 8.2 Hz, ArCH). 13C NMR (100 MHz, CDC13): δ 28.1, 31.5, 38.9, 65.1, 81.0, 122.6, 125.0, 125.3, 125.5, 126.1, 126.3, 127.5, 127.5, 128.3, 128.6, 129.0, 129.1, 134.9, 138.1, 140.1. 140.5, 141.5, 166.1, 171.0.

(E)-3-(5-((E)-3-methylbut-l-en-l-yl)-2-(3-phenylpropanamido)phenyl)acrylic acid (33a): Compound 32a (30 mg, 0.07 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4: 1, 2: 1, 1: 1) provided the title compound as a white soild (18 mg, 0.05 mmol, 71%).

Rf: 0.4 (DCM:MeOH, 10: 1). 1H NMR (400 MHz , MeOD): δ 1.75 (3H, s, CH3), 1.74 (3H, s, CH3), 2.74 (2H, t, J = 7.6 Hz, CH2), 3.04 (2H, t, J = 7.4 Hz, CH2), 3.37 (2H, d, J = 8.7 Hz, CH2), 5.33 (1H, t, J = 8.8 Hz, CH), 6.42 (1H, d, J = 15.7 Hz, CH), 7.15 - 7.23 (3H, m, ArCH), 7.29 - 7.33 (4H, m, ArCH), 7.50 (1H, s, ArCH), 7.70 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz, MeOD): δ 24.4, 31.5, 33.2, 37.7, 122.5, 125.8, 126.8, 128.0, 128.1, 129.9, 130.1, 132.6, 132.8, 133.6, 133.7, 139.1, 140.4, 140.6, 173.2.

(E)-3-(3'-(hydroxymethyl)-4-(3-phenylpropanamido)-[l,l'-biphenyl]-3-yl)acrylic acid (33b): Compound 32b (20 mg, 0.05 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (DCM:MeOH = 20: 1, 10: 1) provided the title compound as a white soild (13 mg, 0.03 mmol, 73%).

Rf: 0.5 (Hexane:EtOAc, 1 : 1). 1H NMR (400 MHz , MeOD): δ 2.79 (2H, t, J = 7.3 Hz, CH2), 3.07 (2H, t, J = 7.8 Hz, CH2), 4.70 (2H, s, CH2), 6.57 (1H, d, J = 15.8 Hz, CH), 7.21 (1H, q, J = 4.4 Hz, ArCH), 7.31 - 7.47 (7H, m, ArCH), 7.57 (1H, d, J = 7.6 Hz, ArCH), 7.65 - 7.67 (2H, m, ArCH), 7.79 (1H, d, J = 15.8 Hz, CH), 7.94 (1H, s, ArCH). 13C NMR (100 MHz, MeOD): δ 31.4, 37.7, 63.7, 124.7, 125.0, 125.4, 125.8, 125.8, 126.9, 128.0, 128.1, 128.4, 128.6, 130.2, 135.1, 139.2, 139.4, 139.9, 140.6, 142.1 173.2.

N-(3-bromo-5-iodophenyl)-3-phenylpropanamide (36): To a solution of 35 (380 mg, 1.3 mmol) in dry DCM (12 mL) was added DMAP (13 mg, 0.1 mmol), a solution of 3-phenyl propanoyl chloride (320 mg, 2 mmol) in DCM (2 mL) and NEt3 (0.4 mL, 3 mmol). The reaction was heated to 700C and stirred overnight. The reaction was allowed to cool and was washed with saturated aqueous NaHC03, water and extracted in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 12: 1, 9: 1, 4: 1, 2: 1) provided the title compound as a white solid (430 mg, 1 mmol, 78%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.67 (2H, t, J = 7.4 Hz, CH2), 3.03 (2H, t, J = 7.5 Hz, CH2), 7.21 - 7.34 (5H, m, ArCH), 7.57 (1H, s, ArCH), 7.65 (1H, s, ArCH), 7.73 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 31.3, 39.3, 94.0, 122.1, 122.9, 126.5, 127.1, 128.3, 128.7, 135.3, 139.6, 140.2, 170.6.

tert-butyl (E)-3-(3-bromo-5-(3-phenylpropanamido)phenyl)acrylate (37): To a solution of 36 (123 mg, 0.3 mmol) in dry toluene (5 mL) was added PPh3 (8 mg, 0.03 mmol) and Pd(OAc)2 (4 mg, 0.01 mmol). tert-butyl acrylate (60 μΕ, 0.4 mmol) and NEt3 (70 μΕ, 0.5 mmol) were added and the reaction was refluxed overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc gradient = 9: 1, 4: 1, 2: 1, 1 : 1, 0: 1) provided the title compound as a brown oil (110 mg, 0.25 mmol, 91%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 2.67 (2H, t, J = 7.4 Hz, CH2), 3.03 (2H, t, J = 7.5 Hz, CH2), 6.31 (1H, d, J = 15.9 Hz, ArCH), 7.20 - 7.24 (5H, m, ArCH), 7.40 (1H, d, J = 15.9 Hz, ArCH), 7.52 (1H, s, ArCH), 7.68 (1H, s, ArCH), 7.71 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 28.1, 31.3, 39.1, 80.9, 117.8, 118.6, 122.0, 122.9, 126.4, 128.3, 128.6, 128.6, 140.3, 165.9, 171.1.

tert-butyl (E)-3-(3-(3-methylbut-2-en-l-yl)-5-(3-phenylpropanamido)phenyl)acrylate (38a): To a solution of 37 (110 mg, 0.2 mmol) in dry DMF (3 mL) was added Cs2C03 (130 mg, 0.4 mmol) and Pd(dppf)C12 (20 mg, 0.02 mmol). Prenyl boronic acid pinacol ester (0.1 mL, 0.4 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1) provided the title compound as a transparent oil (100 mg, 0.2 mmol, 95%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.52 (3H, s, CH3), 1.57 (3H, s, CH3), 2.67 (2H, t, J = 7.4 Hz, CH2), 3.07 (2H, t, J = 7.5 Hz, CH2), 3.31 (2H, d, J = 7.2 Hz, CH2), 5.29 (1H, t, J = 7.3 Hz, CH2), 6.36 (1H, d, J = 15.9 Hz, ArCH), 7.20 - 7.34 (8H, m, ArCH), 7.52 (1H, d, J = 15.9 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 25.7, 28.2, 31.5, 34.1, 39.4, 41.1, 80.5, 110.9, 111.3, 116.7, 120.6, 122.3, 126.3, 126.4, 128.3, 128.6, 128.6, 140.5, 143.2, 147.2, 147.6, 166.2, 170.4.

tert-butyl (E)-3-(3'-(hydroxymethyl)-5-(3-phenylpropanamido)-[l,l'-biphenyl]-3-yl)acrylate (38b): To a solution of 37 (130 mg, 0.3 mmol) in dry DMF (3 mL) was added Cs2C03 (195 mg, 0.6 mmol) and Pd(dppf)C12 (20 mg, 0.02 mmol). (3-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl)methanol (120 mg, 0.5 mmol) was added and the flask was heated at 900C overnight. The reaction was allowed to cool and was extracted over a pad of celite® with EtOAc, the solvent evaporated and re-dissolved in DCM. Residual DMF was removed by washing with copious amounts of water in DCM, the organic layer was dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1, 1 : 1) provided the title compound as a transparent oil (100 mg, 0.2 mmol, 73%). Rf: 0.3 (Hexane:EtOAc, 4: 1). δ 1.55 (9H, s, C(CH3)3), 2.64 (2H, t, J = 7.4 Hz, CH2), 3.09 (2H, t, J = 7.7 Hz, CH2), 4.68 (2H, s, CH2), 6.35 (1H, d, J = 15.9 Hz, ArCH), 7.19 - 7.50 (10H, m, ArCH and CH), 7.56 (1H, s, ArCH), 7.59 (1H, s, ArCH), 8.08 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 28.2, 31.4, 39.0, 64.9, 80.8, 120.3, 120.9, 122.5, 125.6, 126.1, 126.3, 128.3, 128.6, 128.6, 128.9, 129.2, 135.6, 138.7, 140.1, 140.5, 141.5, 142.1, 143.1, 166.3, 171.2.

(E)-3-(3-(3-methylbut-2-en-l-yl)-5-(3-phenylpropanamido)phenyl)acrylic acid (39a): Compound 38a (100 mg, 0.2 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (DCM:MeOH = 20: 1, 10: 1) provided the title compound as a white soild (55 mg, 0.15 mmol, 75%).

Rf: 0.2 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; MeOD): δ 1.75 (3H, s, CH3), 1.78 (3H, s, CH3), 2.68 (2H, t, J = 7.6 Hz, CH2), 3.01 (2H, d, J = 7.6 Hz, CH2), 3.35 (2H, d, J = 7.4 Hz, CH2), 5.33 (1H, t, J = 7.3 Hz, CH), 6.44 (1H, d, J = 15.9 Hz, CH), 7.13 (1H, s, ArCH), 7.17 - 7.21 (1H, m, ArCH), 7.29 - 7.32 (2H, m, ArCH), 7.38 (1H, s, ArCH), 7.55 - 7.70 (3H, m, ArCH). 13C NMR (100 MHz; MeOD): 27.2, 31.3, 33.5, 38.4, 110.3, 116.4, 118.6, 121.5, 122.3, 123.5, 125.8, 128.0, 128.0, 132.7, 139.0, 140.7, 143.2, 144.4, 172.3. HRMS-ESI: (m/z) calculated for C23H25N03, 386.1727 [M+Na]+; found, 386.1739.

(E)-3-(3'-(hydroxymethyl)-5-(3-phenylpropanamido)-[l,r-biphenyl]-3-yl)acrylic acid (39b): Compound 38b (100 mg, 0.2 mmol) was hydrolyzed following the general procedure B. Purification by column chromatography (DCM:MeOH = 20: 1, 10: 1) provided the title compound as a white soild (50 mg, 0.1 mmol, 60%).

Rf: 0.2 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; MeOD): δ 2.72 (2H, t, J = 7.3 Hz, CH2), 3.02 (2H, t, J = 7.7 Hz, CH2), 6.54 (1H, d, J = 15.8 Hz, CH), 7.17 - 7.22 (1H, m, ArCH), 7.28 - 7.29 (4H, m, ArCH), 7.37 - 7.39 (1H, m, ArCH), 7.44 (1H, t, J = 7.5 Hz, ArCH), 7.53 - 7.56 (2H, m, ArCH), 7.64 (1H, s, ArCH), 7.70 (1H, d, J = 16.0 Hz CH) 7.78 (1H, s, ArCH), 7.85 (1H, s, ArCH). 13C NMR (100 MHz; MeOD): 31.3, 38.5, 63.7, 117.5, 120.1, 122.2, 125.2, 125.5, 125.8, 126.0, 128.0, 128.1, 128.6, 135.5, 139.5, 140.0, 140.7, 142.1, 142.4, 144.5, 172.5.

3-bromo-5-iodo-N-phenethylbenzamide (41a): To a solution of 3-bromo-5-iodo benzoic acid (500 mg, 1.5 mmol) in dry toluene (10 mL) was added SOC12 (290 μΐ., 4 mmol) and the mixture was refluxed overnight. The reaction vessel was cooled to room temperature and the solvent was evaporated in vacuo. The resultant brown oil was used further without purification. To a solution of 3-bromo-5-iodo benzoyl chloride in DCM (10 mL) was added DMAP (26 mg, 0.2 mmol) and the flask was purged with nitrogen. 2-phenylethylamine (250 μΐ., 2 mmol) and NEt3 (420 μΐ., 3 mmol) were added to the flask and the mixture was stirred at 70oC overnight. The reaction mixture was cooled to room temperature, diluted with DCM, washed with a saturated aqueous NaHC03, water and extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4: 1) provided the title compound as a white solid ( 645 mg, 1.5 mmol, 98%).

Rf: 0.51 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.93 (2H, t, J = 7.0 Hz, CH2), 3.68 (2H, q, J = 7.0 Hz, CH2), 7.22 - 7.36 (5H, m, ArCH), 7.77 (1H, t, J = 1.6 Hz, ArCH), 7.93 - 7.94 (2H, m, ArCH). 13C NMR (100 MHz; CDC13,): δ 35.5, 41.4, 94.4, 123.2, 126.7, 128.7, 129.5, 134.4, 137.9, 138.5, 142.2, 164.7.

3-bromo-N-(4-fluorophenethyl)-5-iodobenzamide (41b): Following the procedure as described for 41a the title compound was synthesized from 2-(4-fluorophenyl)ethan-l -amine (170 μΐ., 1.2 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a white soild (300 mg, 0.7 mmol, 90%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.91 (2H, t, J = 7.0 Hz, CH2), 3.67 (2H, q, J = 7.0 Hz, CH2), 7.06 (2H, t, J = 8.0 Hz, ArCH), 7.17 - 7.20 (2H, m, ArCH), 7.78 (1H, t, J = 1.3 Hz, ArCH), 7.93 (1H, t, J = 1.4 Hz, ArCH), 7.96 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 34.7, 41.5, 94.5, 115.6, 123.2, 129.4, 130.2, 134.1, 134.6, 137.8, 142.3, 164.7.

3-bromo-5-iodo-N-(4-methoxyphenethyl)benzamide (41c): Following the procedure as described for 41a the title compound was synthesized from 2-(4-methoxyphenyl)ethan-l -amine (180 μΐ., 1.2 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a white soild (420 mg, 0.9 mmol, 95%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.85 (2H, t, J = 7.0 Hz, CH2), 3.61 (2H, q, J = 7.0 Hz, CH2), 3.78 (3H, s, CH3), 6.85 (2H, d, J = 8.6 Hz, ArCH), 7.12 (2H, d, J = 8.6 Hz, ArCH), 7.79 (1H, t, J = 1.3 Hz, ArCH), 7.92 (1H, t, J = 1.4 Hz, ArCH), 7.94 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 34.6, 41.6, 55.2, 94.3, 114.0, 123.1, 129.5, 129.7, 130.5, 134.7, 138.0, 142.1, 158.3, 164.6.

3-bromo-5-iodo-N-(4-methoxybenzyl)benzamide (41d): Following the procedure as described for 41a the title compound was synthesized from (4-methoxyphenyl)methanamine (70 μΐ., 0.5 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a white soild (HO mg, 0.2 mmol, 83%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 3.81 (3H, s, CH3), 4.52 (2H, d, J = 5.5 Hz, CH2), 6.88 (2H, d, J = 8.6 Hz, ArCH), 7.25 (2H, d, J = 8.7 Hz, ArCH), 7.85 (1H, t, J = 1.3 Hz, ArCH), 7.95 (1H, t, J = 1.4 Hz, ArCH), 8.01 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 43.8, 55.3, 94.4, 114.2, 123.2, 129.3, 129.6, 129.6, 134.7, 137.7, 142.3, 159.2, 164.4.

3-bromo-5-iodo-N-(4-(trifluoromethoxy)benzyl)benzamide (41e): Following the procedure as described for 41a the title compound was synthesized from (4-(tafluoromethoxy)phenyl)methanamine (230 μΐ., 1.5 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a white soild (460 mg, 0.7 mmol, 99%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 4.60 (2H, d, J = 5.8 Hz, CH2), 7.19 (2H, d, J = 8.7 Hz, ArCH), 7.35 (2H, d, J = 8.7 Hz, ArCH), 7.87 (1H, t, J = 1.6 Hz, ArCH), 7.98 (1H, t, J = 1.6 Hz, ArCH), 8.02 (1H, t, J = 1.4 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 43.5, 94.5, 121.3, 123.3, 129.3, 129.6, 134.7, 136.3, 137.3, 142.6, 148.7, 164.6.

3-bromo-5-iodo-N-(3-(trifluoromethoxy)benzyl)benzamide (411): Following the procedure as described for 41a the title compound was synthesized from (3-(trifluoromethoxy)phenyl)methanamine (230 uL, 1.5 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a white soild (300 mg, 0.6 mmol, 80%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 4.57 (2H, d, J = 5.8 Hz, CH2), 7.14 (2H, s, ArCH), 7.22 (2H, d, J = 8.7 Hz, ArCH), 7.33 - 7.37 (1H, m, ArCH), 7.84 (1H, t, J = 1.6 Hz, ArCH), 7.95 (1H, t, J = 1.6 Hz, ArCH), 8.00 (1H, t, J = 1.4 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 43.6, 94.5, 120.0, 120.2, 123.2, 126.0, 129.6, 130.1, 134.7, 137.2, 139.9, 142.5, 149.4, 164.8.

3-bromo-5-iodo-N-(4-methylbenzyl)benzamide (41g): Following the procedure as described for 41a the title compound was synthesized from p-tolylmethanamine (200 uL, 1.5 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a white soild (490 mg, 0.7 mmol, 99%).

Rf: 0.4 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.37 (3H, s, CH3), 4.58 (2H, d, J = 5.5 Hz, CH2), 7.18 - 7.28 (4H, m, ArCH), 7.87 (1H, t, J = 1.6 Hz, ArCH), 7.98 (1H, t, J = 1.5 Hz, ArCH), 8.02 (1H, t, J = 1.5 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 21.1, 44.2, 94.4, 123.2, 128.8, 129.5, 134.4, 134.6, 137.7, 142.4, 164.3.

3-bromo-N-(4-(dimethylamino)benzyl)-5-iodobenzamide (41h): Following the procedure as described for 41a the title compound was synthesized from 4-(aminomethyl)-N,N-dimethylaniline (75 uL, 0.5 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a orange soild (130 mg, 0.2 mmol, 83%). Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.97 (6H, s, CH3), 4.51 (2H, d, J = 5.3 Hz, CH2), 6.73 (2H, d, J = 8.7 Hz, ArCH), 7.23 (2H, d, J = 8.7 Hz, ArCH), 7.86 (1H, t, J = 1.6 Hz, ArCH), 7.97 (1H, t, J = 1.5 Hz, ArCH), 8.01 (1H, t, J = 1.5 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 40.1, 40.5, 44.1, 94.4, 110.9, 112.7, 123.2, 124.8, 129.3, 129.5, 134.4, 137.9, 142.2, 150.3, 164.1.

phenethyl 3-bromo-5-iodobenzoate (42): Following the procedure as described for 41a the title compound was synthesized from 2-phenylethan-l-ol (130 μΐ., 1 mmol). Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a yellow oil (170 mg, 0.4 mmol, 80%).

Rf: 0.7 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 3.10 (2H, d, J = 7.0 Hz, CH2), 4.55 (2H, d, J = 7.0 Hz, ArCH), 7.28 - 7.39 (5H, m, ArCH), 8.04 (1H, t, J = 1.7 Hz, ArCH), 8.11 (1H, t, J = 1.6 Hz, ArCH), 8.28 (1H, t, J = 1.5 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 35.1, 66.2, 94.0, 123.0, 126.8, 128.6, 128.9, 131.9, 133.4, 137.1, 137.4, 143.7, 163.7.

tert-butyl (E)-3-(3-bromo-5-(phenethylcarbamoyl)phenyl)acrylate (43a): To a solution of 41a (645 mg, 1.5 mmol) in dry toluene (15 mL), was added PPh3 (40 mg, 0.15 mmol), Pd(OAc)2 (17 mg, 0.07 mmol) and the flask was purged with nitrogen. tert-Butylacrylate (300 μΐ., 2.0 mmol) and NEt3 (560 μΐ., 4.0 mmol) were added and the mixture was stirred at reflux overnight. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a brown oil (288 mg, 0.67 mmol, 45%).

Rf: 0.32 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 2.95 (2H, t, J = 6.9 Hz, CH2), 3.71 (2H, q, J = 6.9 Hz, CH2), 6.37 (1H, d, J = 15.9 Hz, CH), 7.23 - 7.36 (5H, m, ArCH), 7.45 (1H, d, J = 15.9 Hz, CH), 7.70 (2H, s, ArCH), 7.79 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 35.5, 41.3, 81.0, 122.8, 123.1, 124.9, 126.7, 128.7, 128.8, 130.9, 133.1, 137.0, 137.1, 138.6, 140.7, 165.4, 165.5.

tert-but l (E)-3-(3-bromo-5-((4-fluorophenethyl)carbamoyl)phenyl)acrylate (43b): Following the procedure as described for 43a the title compound was obtained as a white soild (70 mg, 0.16 mmol, 24%).

Rf: 0.20 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, (CH3)3), 2.91 (2H, t, J = 7.0 Hz, CH2), 3.69 (2H, q, J = 6.1 Hz, CH2), 6.39 (1H, d, J = 15.9 Hz, CH), 7.03 (2H, t, J = 8.6 Hz, ArCH), 7.18 - 7.21 (2H, m, ArCH), 7.47 (1H, d, J = 15.9 Hz, CH), 7.72 (2H, s, ArCH), 7.79 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 34.8, 41.4, 81.1, 115.4, 122.9, 123.2, 124.9, 130.2, 130.9, 133.1, 134.2, 134.2, 137.0, 137.0, 140.6, 165.4, 165.6.

tert-butyl (E)-3-(3-bromo-5-((4-methoxyphenethyl)carbamoyl)phenyl)acrylate (43c): Following the procedure as described for 43a the title compound was obtained as a white soild (200 mg, 0.4 mmol, 40%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, (CH3)3), 2.87 (2H, t, J = 7.0 Hz, CH2), 3.65 (2H, q, J = 6.1 Hz, CH2), 6.36 (1H, d, J = 15.9 Hz, CH), 6.86 (2H, d, J = 8.9 Hz, ArCH), 7.13 (2H, d, J = 8.6 Hz, ArCH), 7.49 (1H, d, J = 15.9 Hz, CH), 7.69 (1H, t, J = 1.4 Hz, ArCH). 7.72 (1H, t, J = 1.2 Hz, ArCH). 7.79 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 34.6, 41.5, 55.2, 81.0, 114.1, 122.7, 123.1, 125.0, 129.7, 130.5, 131.0, 133.0, 136.9, 137.1, 140.7, 158.3, 158.3, 165.5, 165.6.

tert-but l (E)-3-(3-bromo-5-((4-methoxybenzyl)carbamoyl)phenyl)acrylate (43d): Following the procedure as described for 43a the title compound was obtained as a white soild (40 mg, 0.09 mmol, 36%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, (CH3)3), 3.81 (3H, s, CH3), 4.57 (2H, d, J = 5.5 Hz, CH2), 6.40 (1H, d, J = 15.9 Hz, CH), 6.89 (2H, d, J = 8.9 Hz, ArCH), 7.27 - 7.29 (2H, m, ArCH), 7.48 (1H, d, J = 15.9 Hz, CH), 7.74 (1H, t, J = 1.4 Hz, ArCH). 7.82 (1H, t, J = 1.2 Hz, ArCH). 7.87 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 43.8, 55.3, 81.0, 114.2, 122.9, 123.1, 125.1, 129.4, 129.7, 131.0, 133.1, 136.9, 137.0, 140.7, 159.2, 165.2, 165.4.

tert-butyl (E)-3-(3-bromo-5-((4-(trifluoromethoxy)benzyl)carbamoyl)phenyl)acrylate (43e): Following the procedure as described for 43a the title compound was obtained as a white soild (210 mg, 0.4 mmol,

53' %).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (9H, s, (CH3)3), 4.61 (2H, d, J = 5.8 Hz, CH2), 6.38 (1H, d, J = 15.9 Hz, CH), 7.18 (2H, d, J = 7.9 Hz, ArCH), 7.35 (2H, d, J = 8.6 Hz, ArCH), 7.44 (1H, t, J = 15.9 Hz, CH), 7.72 (1H, t, J = 1.4 Hz, ArCH). 7.82 (1H, t, J = 1.3 Hz, ArCH). 7.88 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 43.4, 81.1, 119.1, 121.2, 121.6, 122.9, 123.2, 125.1, 129.2, 131.0, 133.3, 136.5, 137.1, 140.6, 148.6, 165.4, 165.6.

tert-butyl (E)-3-(3-bromo-5-((3-(trifluoromethoxy)benzyl)carbamoyl)phenyl)acrylate (43f): Following the procedure as described for 43a the title compound was obtained as a white soild (110 mg, 0.2 mmol, 36%).

Rf: 0.28 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.52 (9H, s, (CH3)3), 4.63 (2H, d, J = 5.8 Hz, CH2), 6.38 (1H, d, J = 15.9 Hz, CH), 7.14 - 7.18 (2H, m, ArCH), 7.26 - 7.28 (1H, m, ArCH), 7.36 (1H, t, J = 7.9 Hz, CH), 7.45 (1H, t, J = 15.9 Hz, CH), 7.73 (1H, t, J = 1.4 Hz, ArCH). 7.82 (1H, t, J = 1.3 Hz, ArCH). 7.88 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 43.6, 81.1, 120.0, 120.3, 122.9, 123.2, 125.1, 126.1, 130.2, 131.0, 133.3, 136.5, 137.1, 140.1, 140.6, 165.4, 165.6.

tert-butyl (E)-3-(3-bromo-5-((4-methylbenzyl)carbamoyl)phenyl)acrylate (43 g): Following the procedure as described for 43a the title compound was obtained as a white soild (100 mg, 0.23 mmol, 30%).

Rf: 0.3 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, (CH3)3), 2.34 (3H, s, CH3), 4.55 (2H, d, J = 5.5 Hz, CH2), 6.37 (1H, d, J = 15.9 Hz, CH), 7.15 (2H, d, J = 7.8 Hz, ArCH), 7.22 (2H, d, J = 8.0 Hz, ArCH), 7.44 (1H, d, J = 15.9 Hz, CH), 7.70 (1H, t, J = 1.4 Hz, ArCH). 7.81 (1H, t, J = 1.2 Hz, ArCH). 7.87 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 21.1, 28.1, 44.0, 81.0, 122.8, 123.1, 125.1, 127.9, 129.4, 131.0, 133.1, 134.6, 136.8, 137.0, 137.4, 140.7, 165.4, 165.4.

tert-butyl (E)-3-(3-bromo-5-((4-(dimethylamino)benzyl)carbamoyl)phenyl)acrylate (43h): Following the procedure as described for 43a the title compound was obtained as a brown soild (90 mg, 0.2 mmol, 71%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, (CH3)3), 2.96 (6H, s, CH3), 4.53 (2H, d, J = 5.3 Hz, CH2), 6.41 (1H, d, J = 15.9 Hz, CH), 7.26 - 7.28 (5H, m, ArCH), 7.52 (1H, d, J = 15.9 Hz, CH), 7.80 (1H, t, J = 1.6 Hz, ArCH). 8.05 (1H, t, J = 1.3 Hz, ArCH). 8.11 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ

phenethyl (E)-3-bromo-5-(3-(tert-butoxy)-3-oxoprop-l-en-l-yl)benzoate (44): Following the procedure as described for 43a the title compound was synthesized from 42 as a yellow soild (125 mg, 0.3 mmol, 72%).

Rf: 0.65 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.56 (9H, s, C(CH3)3), 3.10 (2H, t, J = 6.9 Hz, CH2), 4.56 (2H, t, J = 7.0 Hz, CH2), 6.43 (1H, d, J = 15.9 Hz, CH), 7.26 - 7.38 (5H, m, ArCH), 7.45 (1H, d, J = 15.9 Hz, CH), 7.70 (2H, s, ArCH), 7.79 (1H, t, J = 1.6 Hz, ArCH). 13C NMR (100 MHz; CDC13,): δ 21.0, 28.1, 31.5, 66.0, 81.0, 122.9, 126.7, 127.3, 128.5, 128.6, 128.9, 132.6, 133.3, 134.6, 136.9, 137.5, 140.6, 164.6, 165.4, 171.0.

tert-butyl (E)-3-(3-(3-methylbut-2-en-l-yl)-5-(phenethylcarbamoyl)phenyl)acrylate (45a): To a solution of (43a) (80 mg, 0.18 mmol) in dry DMF (2 mL) was added Cs2C03 (130 mg, 0.4 mmol), Pd(dppf)C12 (8.5 mg, 0.01 mmol) and the flask was purged with nitrogen. Prenyl boronic acid pinacol ester (70 μΐ., 0.3 mmol) was added and the mixture was stirred at 90oC overnight. The reaction was allowed to cool and was filtered through a celite® pad with EtOAc. The solvent was evaporated in vacuo, re-dissolved in DCM and the residual DMF removed by washing with copious amounts of water in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4:1, 2: 1) provided the title compound as a transparent oil (50 mg, 0.12 mmol, 66%).

Rf: 0.50 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.77 (3H, s, CH3), 2.95 (2H, t, J = 6.9 Hz, CH2), 3.37 (2H, d, J = 7.3 Hz, CH2), 3.73 (2H, q, J = 6.1 Hz, CH2), 5.28 (1H, t, J = 7.3 Hz), 6.39 (1H, d, J = 15.9 Hz, CH), 7.25 - 7.37 (5H, m, ArCH), 7.41 (1H, s, ArCH), 7.51 (1H, s, ArCH), 7.55 (1H, d, J = 16.0 Hz, CH), 7.61 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 34.0, 35.6, 41.1, 80.6, 121.1, 121.9, 123.7, 126.6, 128.3, 128.7, 128.8, 130.6, 133.7, 135.0, 135.4, 138.8, 142.6, 143.1, 166.0, 167.1.

tert-butyl (E)-3-(3-((4-fluorophenethyl)carbamoyl)-5-(3-methylbut-2-en-l-yl)phenyl)acrylate (45b): Following the procedure as described for 45a the title compound was obtained as a transparent oil (70 mg, 0.16 mmol, 95%).

Rf: 0.22 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.76 (3H, s, CH3), 2.92 (2H, t, J = 6.9 Hz, CH2), 3.37 (2H, d, J = 7.3 Hz, CH2), 3.69 (2H, q, J = 6.1 Hz, CH2), 5.28 (1H, t, J = 7.3 Hz), 6.39 (1H, d, J = 15.9 Hz, CH), 7.02 (2H, t, J = 8.6 Hz, ArCH), 7.20 (2H, t, J = 8.5 Hz, ArCH), 7.41 (1H, s, ArCH), 7.50 (1H, s, ArCH), 7.55 (1H, d, J = 16.0 Hz, CH), 7.62 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 28.1, 34.0, 34.9, 41.2, 80.7, 115.4, 115.6, 121.2, 121.9, 123.6, 128.3, 130.1, 130.2, 130.7, 133.7, 135.1, 135.3, 142.6, 143.1, 166.0,

tert-but l (E)-3-(3-((4-methoxyphenethyl)carbamo (45c): Following the procedure as described for 45a the title compound was obtained as a transparent oil (90 mg, 0.2 mmol, 46%).

Rf: 0.50 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.77 (3H, s, CH3), 2.89 (2H, t, J = 6.9 Hz, CH2), 3.37 (2H, d, J = 7.3 Hz, CH2), 3.68 (2H, q, J = 6.1 Hz, CH2), 3.81 (3H, s, CH3), 5.28 (1H, t, J = 5.9 Hz), 6.39 (1H, d, J = 15.9 Hz, CH), 6.89 (2H, d, J = 8.6 Hz, ArCH), 7.17 (2H, t, J = 8.6 Hz, ArCH), 7.41 (1H, s, ArCH), 7.51 (1H, s, ArCH), 7.56 (1H, d, J = 16.0 Hz, CH), 7.62 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 34.0, 34.7, 41.3, 55.2, 80.7, 114.1, 121.1, 121.9, 123.7, 128.3, 129.7, 130.6, 130.7, 133.7, 135.0, 135.5, 142.6, 143.1, 158.3, 166.0, 167.1.

tert-butyl (E)-3-(3-((4-methoxybenzyl)carbamoyl)-5-(3-methylbut-2-en-l-yl)phenyl)acrylate (45d): Following the procedure as described for 45a the title compound was obtained as a transparent oil (30 mg, 0.06 mmol, 76%).

Rf: 0.17 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.73 (3H, s, CH3), 1.77 (3H, s, CH3), 3.39 (2H, d, J = 7.2 Hz, CH2), 3.82 (3H, s, CH3), 4.59 (2H, d, J = 5.5 Hz, CH2), 5.29 (1H, t, J = 8.2 Hz), 6.40 (1H, d, J = 15.9 Hz, CH), 6.91 (2H, d, J = 8.6 Hz, ArCH), 7.30 (2H, d, J = 8.5 Hz, ArCH), 7.43 (1H, s, ArCH), 7.57 (1H, d, J = 16.0 Hz, CH), 7.60 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 34.0, 43.7, 55.3, 80.6, 114.2, 121.2, 121.9, 123.7, 128.4, 129.3, 130.1, 130.7, 133.7, 135.1, 135.2, 142.6, 143.1, 159.1, 165.9, 166.9.

tert-butyl (E)-3-(3-(3-methylbut-2-en-l-yl)-5-((4-(trifluoromethoxy)benzyl)carbamoyl)phenyl)acty (45e): Following the procedure as described for 45a the title compound was obtained as a transparent oil (140 mg, 0.3 mmol, 53%).

Rf: 0.25 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.73 (3H, s, CH3), 1.77 (3H, s, CH3), 3.39 (2H, d, J = 7.2 Hz, CH2), 3.82 (3H, s, CH3), 4.59 (2H, d, J = 5.5 Hz, CH2), 5.29 (1H, t, J = 8.2 Hz), 6.40 (1H, d, J = 15.9 Hz, CH), 6.91 (2H, d, J = 8.6 Hz, ArCH), 7.30 (2H, d, J = 8.5 Hz, ArCH), 7.43 (1H, s, ArCH), 7.57 (1H, d, J = 16.0 Hz, CH), 7.60 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 34.0, 43.7, 55.3, 80.6, 114.2, 121.2, 121.9, 123.7, 128.4, 129.3, 130.1, 130.7, 133.7, 135.1, 135.2, 142.6, 143.1, 159.1, 165.9, 166.9.

tert-butyl (E)-3-(3-(3-methylbut-2-en-l-yl)-5-((3-(trifluoromethoxy)benzyl)carbamoyl)phenyl)acrylate (45f): Following the procedure as described for 45a the title compound was obtained as a transparent oil (60 mg, 0.1 mmol, 55%).

Rf: 0.27 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.53 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.76 (3H, s, CH3), 3.32 (2H, d, J = 7.8 Hz, CH2), 4.66 (2H, d, J = 5.8 Hz, CH2), 5.27 (1H, t, J = 8.6 Hz), 6.40 (1H, d, J = 15.9 Hz, CH), 7.14 - 7.21 (2H, m, ArCH), 7.28 - 7.31 (1H, m, ArCH), 7.37 (1H, d, J = 7.9 Hz, ArCH), 7.43 (1H, s, ArCH), 7.55 (1H, d, J = 16.0 Hz, CH), 7.62 (1H, s, ArCH), 7.73 (1H, s, ArCH) 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 34.0, 43.4, 80.7, 119.9, 120.2, 121.3, 121.9, 123.8, 126.0, 128.5, 130.1, 130.9, 133.8, 134.8, 135.2, 140.6, 142.5, 143.2, 149.4, 149.5, 166.0, 167.1.

tert-buty 1 (E)-3-(3 -((4-methy lbenzy l)carbamoy l)-5 -(3 -methy lbut-2-en- 1 -y l)pheny 1) aery late (45g) : Following the procedure as described for 45a the title compound was obtained as a transparent oil (70 mg, 0.16 mmol, 72%).

Rf: 0.35 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.54 (9H, s, C(CH3)3), 1.72 (3H, s, CH3), 1.76 (3H, s, CH3), 2.36 (3H, s, CH3), 3.37 (2H, d, J = 7.2 Hz, CH2), 4.60 (2H, d, J = 5.4 Hz, CH2), 5.28 (1H, t, J = 8.6 Hz), 6.40 (1H, d, J = 15.9 Hz, CH), 7.17 (2H, d, J = 7.8 Hz, ArCH), 7.26 (2H, d, J = 8.0 Hz, ArCH), 7.42 (1H, s, ArCH), 7.56 (1H, d, J = 16.0 Hz, CH), 7.61 (1H, s, ArCH), 7.72 (1H, s, ArCH) 13C NMR (100 MHz; CDC13,): δ 17.9, 21.1, 25.7, 28.1, 34.0, 43.9, 80.6, 121.2, 122.0, 123.8, 128.0, 128.5, 129.4, 130.7, 133.7, 135.0, 135.1, 135.2, 137.3, 142.6, 143.1, 166.0, 166.9.

tert-butyl (E)-3-(3-((4-(dimethylamino)benzyl)carbamoyl)-5-(3-methylbut-2-en-l-yl)phenyl)acrylate (45h): Following the procedure as described for 45a the title compound was obtained as a transparent oil (40 mg, 0.09 mmol, 44%).

Rf: 0.15 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 1.73 (3H, s, CH3), 1.77 (3H, s, CH3), 2.97 (6H, s, CH3), 3.39 (2H, d, J = 7.2 Hz, CH2), 4.55 (2H, d, J = 5.3 Hz, CH2), 5.29 (1H, t, J = 7.1 Hz), 6.40 (1H, d, J = 15.9 Hz, CH), 6.74 (2H, d, J = 8.6 Hz, ArCH), 7.26 (2H, d, J = 8.6 Hz, ArCH), 7.42 (1H, s, ArCH), 7.57 (1H, d, J = 16.0 Hz, CH), 7.59 (1H, s, ArCH), 7.70 (1H, s, ArCH) 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 34.0, 40.6, 43.9, 80.6, 112.7, 121.2, 122.0, 123.7, 125.4, 128.4, 129.2, 130.6, 133.6, 135.1, 135.4, 142.6, 143.1, 150.2, 166.0, 166.8.

tert-butyl (E)-3-(3-allyl-5-(phenethylcarbamoyl)phenyl)acrylate (46): Following the procedure as described for 45a the title compound was obtained using allyl boronic acid pinacol ester as a transparent oil (50 mg, 0.1 mmol, 49%).

Rf: 0.26 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, C(CH3)3), 2.96 (2H, t, J = 6.9 Hz, CH2), 2.43 (2H, d, J = 6.6 Hz, CH2), 3.73 (2H, q, J = 5.9 Hz, CH2), 5.09 - 5.15 (2H, m, CH2), 5.89 - 5.99 (1H, m, CH), 6.40 (1H, d, J = 15.9 Hz, CH), 7.25 - 7.30 (3H, m, ArCH), 7.34 - 7.38 (2H, m, ArCH), 7.44 (1H, s, ArCH), 7.52 (1H, s, ArCH), 7.56 (1H, d, J = 16.0 Hz, CH), 7.63 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 35.6, 39.8, 41.7, 80.7, 116.9, 121.3, 126.6, 128.5, 128.7, 128.8, 129.6, 130.8, 135.2, 135.5, 136.2, 138.8, 141.3, 142.4, 165.9, 167.0.

tert-butyl (E)-3-(3'-(hydroxymethyl)-5-( henet^^ (47): Following the procedure as described for 45a the title compound was obtained using hydroxymethyl phenyl boronic acid pinacol ester as a transparent oil (50 mg, 0.1 mmol, 49%).

Rf: 0.65 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.56 (9H, s, C(CH3)3), 2.98 (2H, t, J = 6.8 Hz, CH2), 3.74 (2H, q, J = 6.1 Hz, CH2), 4.77 (2H, s, CH2), 6.43 (1H, d, J = 15.9 Hz, CH), 7.25 - 7.48 (8H, m, ArCH), 7.56 (1H, s, ArCH), 7.58 (1H, d, J = 15.9 Hz, CH), 7.73 (1H, s, ArCH), 7.75 (1H, s, ArCH), 7.87 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 28.1, 35.6, 41.2, 80.8, 121.7, 124.9, 125.6, 126.2, 126.6, 126.6, 127.0, 128.7, 128.8, 129.1, 135.5, 135.9, 138.8, 139.7, 141.8, 142.0, 142.2, 165.9, 167.0.

phenethy 1 (E)-3-(3 -(tert-butoxy)-3-oxoprop- 1 -en- 1 -y l)-5-(3 -methy lbut-2-en- 1 -y l)benzoate (48) : Following the procedure as described for 45a the title compound was synthesized from 44 as a transparent oil (67 mg, 0.1 mmol, 90%).

Rf: 0.57 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.57 (9H, s, C(CH3)3), 1.75 (3H, s, CH3), 1.79 (3H, s, CH3), 3.11 (2H, t, J = 6.9 Hz, CH2), 3.40 (2H, d, J = 7.3 Hz, CH2), 4.55 (2H, t, J = 6.9 Hz, CH2), 5.30 (1H, t, J = 7.3 Hz), 6.43 (1H, d, J = 15.9 Hz, CH), 7.28 - 7.38 (5H, m, ArCH), 7.49 (1H, s, ArCH), 7.60 (1H, d, J = 16.0 Hz, CH), 7.83 (1H, s, ArCH), 7.98 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 17.9, 25.7, 28.1, 28.2, 34.0, 35.2, 80.6, 121.2, 122.0, 126.4, 126.6, 128.5, 129.0, 130.8, 130.9, 132.2, 133.7, 135.0, 137.8, 142.6, 142.9, 166.0, 166.1.

(E)-3-(3-(3-methylbut-2-en-l-yl)-5-(phenethylcarbamoyl)phenyl)acrylic acid (49a): To a solution of (45a) (50 mg, 0.12 mmol) in dry toluene (10 mL) was added silica gel (5 mL) and the suspension was stirred at reflux overnight. The reaction was allowed to cool and the mixture was filtered after diluting with 20% MeOH in DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (DCM:MeOH = 20: 1) provided the title compound as a white solid (21.7 mg, 0.06 mmol, 50%).

Rf: 0.27 (DCM: MeOH, 20: 1). 1H NMR (400 MHz; MeOD): δ 1.77 (3H, s, CH3), 1.78 (3H, s, CH3), 2.94 (2H, t, J = 7.3 Hz, CH2), 3.43 (2H, d, J = 7.4 Hz, CH2), 3.59 - 3.64 (2H, m, CH2), 5.35 (1H, t, J = 7.4 Hz), 6.53 (1H, d, J = 16.0 Hz, CH), 7.20 - 7.32 (5H, m, ArCH), 7.54 (1H, s, ArCH), 7.63 (1H, s, ArCH), 7.68 (1H, d, J = 16.0 Hz, CH), 7.80 (1H, s, ArCH). 13C NMR (100 MHz; CDC13,): δ 16.5, 24.5, 33.4, 35.0, 41.2, 119.1, 122.0, 123.7, 125.9, 128.1, 128.5, 128.6, 130.6, 133.0, 134.8, 135.2, 139.1, 143.1, 143.9, 168.3, 168.6. HRMS-ESI: (m/z) calculated for C23H25N03 , 386.1727 [M+Na] +; found, 386.1736.

(E)-3-(3-((4-fluorophenethyl)carbamoyl)-5-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (49b): Following the procedure as described for 49a the title compound was obtained as a white solid (20 mg, 0.05 mmol, 41%).

Rf: 0.22 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CD30D): δ 1.77 (3H, s, CH3), 1.79 (3H, s, CH3), 2.92 (2H, t, J = 7.3 Hz, CH2), 3.44 (2H, d, J = 7.2 Hz, CH2), 3.58 - 3.62 (2H, m, CH2), 5.35 (1H, t, J = 7.2 Hz, CH), 6.54 (1H, d, J = 16.0 Hz, CH), 7.03 (2H, t, J = 8.9 Hz, ArCH). 7.28 (2H, q, Jl = 5.4 Hz, J2 = 3.1 Hz, ArCH), 7.56 (1H, s, ArCH), 7.63 (1H, s, ArCH), 7.68 (1H, d, J = 15.9 Hz, CH), 7.81 (1H, s, ArCH). 13C NMR (100 MHz; CD30D): δ 16.5, 24.5, 33.4, 34.2, 41.2, 110.7, 114.5, 114.7, 122.0, 123.7, 128.5, 130.1, 130.1, 130.6, 133.1, 134.8, 135.1, 143.2, 147.0, 160.4, 168.3. HRMS-ESI: (m/z) calculated for C23H24N03F, 382.1813 [M+H] +; found, 382.1804.

(E)-3-(3-((4-methoxyphenethyl)carbamoyl)-5-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (49c): Following the procedure as described for 49a the title compound was obtained as a white solid (26 mg, 0.06 mmol, 30%).

Rf: 0.25 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CD30D): δ 1.77 (3H, s, CH3), 1.79 (3H, s, CH3), 2.87 (2H, t, J = 7.4 Hz, CH2), 3.44 (2H, d, J = 7.2 Hz, CH2), 3.57 (2H, q, Jl = 7.3 Hz, J2 = 6.3 Hz, CH2), 3.77 (3H, s, CH3), 5.35 (1H, t, J = 7.3 Hz, CH), 6.54 (1H, d, J = 15.9 Hz, CH), 6.87 (2H, d, J = 8.6 Hz, ArCH), 7.18 (2H, d, J = 8.6 Hz, ArCH), 7.55 (1H, s, ArCH), 7.63 (1H, s, ArCH), 7.67 (1H, d, J = 16.0 Hz, CH), 7.80 (1H, s, ArCH), 8.61 (1H, t, J = 5.5 Hz, -NH). 13C NMR (100 MHz; CD30D): δ 16.5, 24.5, 33.4, 34.2, 41.4, 54.2, 110.7, 113.4, 122.0, 123.6, 128.5, 129.4, 130.6, 131.0, 133.0, 134.8, 135.2, 135.3, 143.1, 149.9, 158.3, 168.3.

(E)-3-(3-((4-methoxybenzyl)carbamoyl)-5-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (49d): Following the procedure as described for 49a the title compound was obtained as a white solid (12 mg, 0.03 mmol, 45%).

Rf: 0.25 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CD30D): δ 1.76 (3H, s, CH3), 1.78 (3H, s, CH3), 3.44 (2H, d, J = 7.3 Hz, CH2), 3.78 (3H, s, CH3), 4.52 (2H, d, J = 4.1 Hz, CH2), 5.35 (1H, t, J = 7.3 Hz, CH), 6.55 (1H, d, J = 16.0 Hz, CH), 6.90 (2H, d, J = 8.7 Hz, ArCH), 7.29 (2H, d, J = 8.7 Hz, ArCH), 7.55 (1H, s, ArCH), 7.68 (1H, d, J = 16.0 Hz, CH), 7.71 (1H, s, ArCH), 7.89 (1H, s, ArCH), 9.00 (1H, t, J = 5.6 Hz, -NH). 13C NMR (100 MHz; CD30D): δ 16.5, 24.4, 33.4, 42.6, 54.2, 110.7, 113.5, 119.4, 122.0, 123.8, 128.5, 130.6, 130.7, 133.0, 134.9, 135.1, 143.2, 143.7, 159.0, 168.0. HRMS-ESI: (m/z) calculated for C23H25N04, 402.1676 [M+Na] +; found, 402.1669.

(E)-3-(3-(3-methylbut-2-en-l-yl)-5-((4-(trifluoromethoxy)benzyl)carbamoyl)phenyl)acrylic acid (49e): Following the procedure as described for 49a the title compound was obtained as a white solid (39 mg, 0.09 mmol, 75%).

Rf: 0.25 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CD30D): δ 1.77 (3H, s, CH3), 1.78 (3H, s, CH3), 3.45 (2H, d, J = 7.2 Hz, CH2), 4.61 (2H, s, CH2), 5.36 (1H, t, J = 7.3 Hz, CH), 6.56 (1H, d, J = 15.9 Hz, CH), 7.26 (2H, d, J = 7.9 Hz, ArCH), 7.47 (2H, d, J = 8.7 Hz, ArCH), 7.58 (1H, s, ArCH), 7.69 (1H, d, J = 16.0 Hz, CH), 7.73 (1H, s, ArCH), 7.92 (1H, s, ArCH). NMR (100 MHz; CD30D): δ 16.5, 24.4, 33.4, 42.4, 119.3, 119.3, 120.7, 122.0, 123.8, 128.7, 128.8, 130.7, 133.1, 134.8, 134.9, 138.1, 143.3, 143.8, 148.1, 168.2. HRMS-ESI: (m/z) calculated for C23H22N04F3, 456.1393 [M+Na] +; found, 456.1403.

(E)-3-(3-(3-methylbut-2-en-l-yl)-5-((3-(trifluoromethoxy)benzyl)carbamoyl)phenyl)acrylic acid (49f): Following the procedure as described for 49a the title compound was obtained as a white solid (18 mg, 0.04 mmol, 33%).

Rf: 0.21 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CD30D): δ 1.77 (3H, s, CH3), 1.78 (3H, s, CH3), 2.87 (2H, t, J = 7.4 Hz, CH2), 3.45 (2H, d, J = 7.5 Hz, CH2), 4.63 (2H, d, Jl = 4.0 Hz, CH2), 5.36 (1H, t, J = 7.3 Hz, CH), 6.56 (1H, d, J = 16.0 Hz, CH), 7.18 (2H, d, J = 8.1 Hz, ArCH), 7.29 (1H, s, ArCH), 7.37 - 7.47 (2H, m, ArCH), 7.58 (1H, s, ArCH), 7.73 (1H, s, ArCH), 7.70 (1H, d, J = 16.0 Hz, CH), 7.92 (1H, s, ArCH). NMR (100 MHz; CD30D): δ 16.5, 24.4, 33.4, 42.6, 119.2, 119.6, 122.0, 123.8, 125.8, 128.6, 129.8, 130.8, 133.1, 134.8, 134.9, 141.6, 143.3, 143.9, 149.3, 150.1, 168.2, 168.6. HRMS-ESI: (m/z) calculated for C23H22N04F3, 456.1393 [M+Na] +; found, 456.1387.

(E)-3 -(3 -((4-methy lbenzy l)carbamoy l)-5 -(3 -methy lbut-2-en- 1 -y l)pheny l)acry lie acid (49g) : Following the procedure as described for 49a the title compound was obtained as a white solid (18 mg, 0.05 mmol, 30%).

Rf: 0.20 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CD30D): δ 1.76 (3H, s, CH3), 1.77 (3H, s, CH3), 2.31 (3H, s, CH3), 3.43 (2H, d, J = 7.3 Hz, CH2), 4.54 (2H, d, J = 5.4 Hz, CH2), 5.35 (1H, t, J = 7.3 Hz, CH), 6.54 (1H, d, J = 16.0 Hz, CH), 7.15 (2H, d, J = 7.8 Hz, ArCH), 7.24 (2H, d, J = 8.0 Hz, ArCH), 7.55 (1H, s, ArCH), 7.68 (1H, d, J = 16.0 Hz, CH), 7.71 (1H, s, ArCH), 7.90 (1H, s, ArCH), 9.03 (1H, t, J = 5.7 Hz, -NH). NMR (100 MHz; CD30D): δ 16.5, 19.7, 24.5, 33.4, 42.9, 119.1, 122.0, 123.8, 127.1, 128.7, 128.7, 130.6, 133.0, 134.8, 135.0, 135.6, 136.5, 143.2, 143.9, 168.0, 168.7. HRMS-ESI: (m/z) calculated for C23H25N03, 364.1907 [M+H] +; found, 364.1899.

(E)-3-(3-((4-(dimethylamino)benzyl)carbamoyl)-5-(3-methylbut-2-en-l-yl)phenyl)acrylic acid (49h): Following the procedure as described for 49a the title compound was obtained as a white solid (15 mg, 0.04 mmol, 42%).

Rf: 0.27 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CD30D): δ 1.77 (3H, s, CH3), 1.78 (3H, s, CH3), 2.91 (6H, s, N(CH3)2), 3.44 (2H, d, J = 7.2 Hz, CH2), 4.48 (2H, d, J = 5.6 Hz, CH2), 5.36 (1H, t, J = 7.3 Hz, CH), 6.55 (1H, d, J = 16.0 Hz, CH), 6.78 (2H, d, J = 8.7 Hz, ArCH), 7.23 (2H, d, J = 8.7 Hz, ArCH), 7.55 (1H, s, ArCH), 7.67 (1H, d, J = 16.0 Hz, CH), 7.71 (1H, s, ArCH), 7.89 (1H, s, ArCH), 8.92 (1H, t, J = 5.9 Hz, -NH). NMR (100 MHz; CD30D): δ 16.5, 24.4, 33.4, 39.7, 42.8, 112.9, 119.4, 122.1, 123.7, 126.9, 128.2, 128.7, 130.5, 133.0, 134.9, 135.2, 143.1, 143.7, 150.2, 168.0, 168.9. HRMS-ESI: (m/z) calculated for C24H28N203, 393.2173 [M+H] +; found, 393.2169.

(E)-3-(3-allyl-5-(phenethylcarbamoyl)phenyl)acrylic acid (50): Following the procedure as described for 49a the title compound was synthesized using 46 as a white solid (11 mg, 0.03 mmol, 27%).

Rf: 0.26 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; MeOD): δ 2.94 (2H, t, J = 7.1 Hz, CH2), 3.48 (2H, d, J = 6.7 Hz, CH2), 3.60 (2H, t, J = 7.8 Hz, CH2), 5.11 - 5.17 (2H, m, CH2), 5.96 - 6.06 (1H, m, CH), 6.55 (1H, d, J = 16.0 Hz, CH), 7.20 - 7.32 (5H, m, ArCH), 7.59 (1H, s, ArCH), 7.66 (1H, s, ArCH), 7.70 (1H, s, ArCH), 7.82 (1H, d, J = 16.0 Hz, CH). 13C NMR (100 MHz; CDC13,): δ 35.0, 39.3, 41.2, 115.5, 124.0, 125.9, 127.6, 128.1, 128.5, 128.8, 129.4, 130.8, 134.9, 135.3, 136.5, 139.1, 141.5, 143.6, 168.1. HRMS-ESI: (m/z) calculated for C21H21N03, 336.1594 [M+H] +; found, 336.1595.

(E)-3-(3'-(hydroxymethyl)-5-( henethylcarbamoyl)-[l,r-biphenyl]-3-yl)acrylic acid (51): Following the procedure as described for 49a the title compound was synthesized using 47 as a white solid (14 mg, 0.03 mmol, 35%).

Rf: 0.19 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CDC13): δ 2.97 (2H, t, J = 7.1 Hz, CH2), 3.65 (2H, t, J = 7.5 Hz, CH2), 4.72 (2H, s, CH2), 6.66 (1H, d, J = 16.0 Hz, CH), 7.22 - 7.50 (7H, m, ArCH), 7.62 (1H, d, J = 7.5 Hz, ArCH), 7.71 (1H, s, ArCH), 7.75 (1H, d, J = 15.9 Hz, CH), 7.99 (2H, d, J = 4.8 Hz, ArCH), 8.06 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 35.0, 41.3, 63.6, 124.7, 124.8, 125.2, 125.6, 126.0, 126.3, 126.9, 128.1, 128.5, 128.7, 129.1, 129.6, 135.6, 135.7, 139.1, 139.5, 142.1, 142.2, 168.0.

(E)-3-(3-(3-methylbut-2-en-l-yl)-5-(phenethoxycarbonyl)phenyl)acrylic acid (52): Following the procedure as described for 49a the title compound was synthesized using 48 as a white solid (30 mg, 0.08 mmol, 51%).

1H NMR (400 MHz; CDC13): δ 1.76 (3H, s, CH3), 1.80 (3H, s, CH3), 3.12 (2H, t, J = 7.0 Hz, CH2), 3.42 (2H, d, J = 7.2 Hz, CH2), 4.57 (2H, t, J = 6.9 Hz, CH2), 5.32 (1H, t, J = 7.3 Hz, CH), 6.51 (1H, d, J = 15.9 Hz, CH), 7.29 - 7.38 (5H, m, ArCH), 7.53 (1H, s, ArCH), 7.80 (1H, d, J = 15.9 Hz, CH), 7.87 (1H, s, ArCH), 8.02 (1H, s, ArCH). 13C NMR (100 MHz; CDC13): δ 17.9, 25.7, 33.9, 35.2, 65.7, 118.1, 121.8, 126.7, 128.5, 128.9, 129.0, 131.1, 131.5, 132.5, 133.9, 134.3, 137.7, 143.1, 146.0, 166.0, 171.3. HRMS-ESI: (m/z) calculated for C23H2404, 387.1567 [M+Na] +; found, 387.1573.

benzyl 3-(benzyloxy)-5-bromobenzoate (54a): To a solution of 3-bromo-5-hydroxy benzoic acid (200 mg, 1 mmol) in DIPEA (0.4 mL, 2.4 mmol) was added benzyl bromide (0.2 mL, 2.2 mmol) and the solution was heated at 150 oC overnight. The solution was allowed to cool and extracted with EtOAc, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4: 1, 2: 1) provided the title compound as a transparent oil. (310 mg, 0.8 mmol, 80%).

Rf: 0.6 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): 5 5.11 (2H, s, CH2), 5.41 (2H, s, CH2), 7.34 - 7.51 (11H, m, ArCH), 7.68 (1H, q, J = 1.3 Hz, ArCH), 7.88 (1H, t, J = 1.4 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 67.2, 70.5, 114.6, 122.8, 123.0, 125.2, 127.6, 128.3, 128.4, 128.7, 128.7, 128.8, 132.8, 135.6, 135.9, 159.3, 164.9.

3 -methoxy benzyl 3-bromo-5-((3-methoxybenzyl)oxy)benzoate (54b): Following the procedure as described for 54a the title compound was obtained as a transparent oil. (270 mg, 0.59 mmol, 51%).

1H NMR (400 MHz; CDC13): δ 3.84 (3H, s, CH3), 3.85 (3H, s, CH3), 5.07 (2H, s, CH2), 5.35 (2H, s, CH2), 6.90 - 7.05 (6H, m, ArCH), 7.30 - 7.36 (3H, m, ArCH), 7.63 (1H, q, J = 1.3 Hz, ArCH), 7.83 (1H, t, J = 1.4 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 55.2, 67.0, 70.3, 112.9, 113.8, 113.8, 113.8, 114.6, 119.7, 120.4, 122.7, 123.0, 125.2, 129.7, 129.7, 132.7, 137.1, 137.4, 159.3, 159.8, 159.9, 164.9.

3-(benzyloxy)-5-bromobenzoic acid (55a): To a solution of 54a in MeOH was added 1M KOH (10 mL) and refluxed for 4 h. The pH of the solution was adjusted to 3 and extracted with EtOAc, dried (Na2S04), filtered and concentrated to provide the title compound as a white soild. (250 mg, 0.8 mmol, 99%). Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 5.07 (2H, s, CH2), 7.29 - 7.43 (6H, m, ArCH), 7.57 (1H, q, J = 1.3 Hz, ArCH), 7.71 (1H, t, J = 1.4 Hz, ArCH). 13C NMR (100 MHz; CDC13): δ 70.0, 114.4, 122.1, 124.6, 127.2, 127.7, 128.2, 133.4, 136.3, 159.5, 166.5.

3-bromo-5-((3-methoxybenzyl)oxy)benzoic acid (55b): Following the procedure as described for 55a the title compound was obtained as a white soild. (160 mg, 0.47 mmol, 78%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 3.79 (3H, s, CH3), 5.09 (2H, s, CH2), 6.79 - 7.00 (4H, m, ArCH), 7.37 (1H, s, CH3), 7.58 (1H, s, CH3), 7.75 (1H, s, CH3). 13C NMR (100 MHz; CDC13): δ 63.7, 69.9, 114.4, 118.6, 119.3, 122.1, 122.1, 124.6, 128.9, 129.2, 133.6, 137.8, 142.9, 159.5, 166.5.

3-(benzyloxy)-5-bromo-N-phenethylbenzamide (57a): To a solution of 55a (250 mg, 0.8 mmol) in dry toluene (7 mL) was added SOC12 (220 μΐ., 3 mmol) and the mixture was refluxed overnight. The reaction vessel was cooled to room temperature and the solvent was evaporated in vacuo. The resultant brown oil was used further without purification. To a solution of the acid chloride in DCM (10 mL) was added DMAP (26 mg, 0.2 mmol) and the flask was purged with nitrogen. 2-phenylethylamine (250 μΐ., 2 mmol) and NEt3 (350 μΐ., 2.5 mmol) were added to the flask and the mixture was stirred at 70oC overnight. The reaction mixture was cooled to room temperature, diluted with DCM, washed with a saturated aqueous NaHC03, water and extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 10: 1, 4: 1) provided the title compound as a white solid ( 180 mg, 0.4 mmol, 50%).

Rf: 0.2 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.92 (2H, t, J = 7.0 Hz, CH2), 3.69 (2H, q, J = 6.0 Hz, CH2), 5.03 (2H, s, CH2), 7.23 - 7.42 (13H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 35.6, 41.3, 70.4, 112.4, 121.2, 122.3, 122.9, 126.6, 127.5, 128.3, 128.7, 128.8, 128.8, 135.9, 137.5, 138.7, 159.5, 166.0.

3-bromo-5-((3-methoxybenzyl)oxy)-N-phenethylbenzamide (57b): Following the procedure as described for 57a the title compound was obtained as a white soild. (130 mg, 0.3 mmol, 60%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 2.94 (2H, t, J = 7.0 Hz, CH2), 3.70 (2H, q, J = 6.0 Hz, CH2), 3.84 (3H, s, CH3), 5.04 (2H, s, CH2), 7.89 - 7.00 (2H, m, ArCH), 7.23 - 7.37 (10H, m, ArCH). 13C NMR (100 MHz; CDC13): δ 35.6, 41.3, 55.2, 70.3, 112.4, 112.9, 113.7, 119.6, 121.2, 122.2, 122.9, 126.6, 128.7, 128.8, 129.7, 137.4, 137.5, 138.7, 159.5, 159.8, 165.9.

tert-butyl (E)-3-(3-(benzyloxy)-5-(phenethylcarbamoyl)phenyl)acrylate (58a): To a solution of 57a (100 mg, 0.3 mmol) in dry DMF (1.5 mL), was added DABCO (4 mg, 0.03 mmol), Pd(OAc)2 (4 mg, 0.015 mmol) and the flask was purged with nitrogen. tert-Butylacrylate (60 μΐ., 0.4 mmol) and K2C03 (55 mg, 0.4 mmol) were added and the mixture was stirred at 120oC for 18 h. The reaction was allowed to cool and washed with saturated aqueous NH4C1, brine, extracted with DCM, dried (Na2S04), filtered and concentrated. Purification by column chromatography (Hexane:EtOAc = 9: 1, 4: 1, 2: 1) provided the title compound as a white solid. (30 mg, 0.06 mmol, 22%).

Rf: 0.21 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, (CH3)3), 2.96 (2H, t, J = 7.0 Hz, CH2), 3.73 (2H, q, J = 6.0 Hz, CH2), 5.11 (2H, s, CH2), 6.37 (1H, d, J = 15.9 Hz, CH), 7.21 - 7.46 (13H, m, ArCH), 7.52 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 28.1, 35.6, 41.1, 70.3, 80.8, 114.6, 117.2, 118.5, 121.7, 126.7, 127.5, 128.2, 128.6, 128.7, 128.8, 136.1, 136.3, 136.7, 142.2, 159.2, 165.8, 166.7.

tert-butyl (E)-3-(3-((3-methoxybenzyl)oxy)-5-(phenethylcarbamoyl)phenyl)acrylate (58b): Following the procedure as described for 58a the title compound was obtained as a white solid. (30 mg, 0.06 mmol, 20%).

Rf: 0.1 (Hexane:EtOAc, 4: 1). 1H NMR (400 MHz; CDC13): δ 1.55 (9H, s, (CH3)3), 2.96 (2H, t, J = 7.0 Hz, CH2), 3.72 (2H, q, J = 6.0 Hz, CH2), 3.84 (3H, s, CH3), 5.08 (2H, s, CH2), 6.37 (1H, d, J = 15.9 Hz, CH), 7.20 - 7.38 (12H, m, ArCH), 7.52 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; CDC13): δ 28.1, 35.6, 41.1, 55.2, 70.1, 80.8, 112.9, 113.7, 114.7, 117.1, 118.5, 119.6, 121.7, 126.7, 128.7, 128.7, 128.8, 129.7, 136.3, 136.7, 137.7, 138.7, 142.2, 159.8, 165.8, 166.7.

(E)-3-(3-(benzyloxy)-5-(phenethylcarbamoyl)phenyl)acrylic acid (59a): Following the general procedure B the title compound was obtained as a white solid (8 mg, 0.02 mmol, 33%).

Rf: 0.3 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; MeOD): δ 2.94 (2H, t, J = 7.0 Hz, CH2), 3.61 (2H, t, J = 6.0 Hz, CH2), 5.18 (2H, s, CH2), 6.55 (1H, d, J = 15.9 Hz, CH), 7.20 - 7.49 (12H, m, ArCH), 7.58 (1H, s, ArCH), 7.65 (1H, d, J = 15.9 Hz, CH). 13C NMR (100 MHz; MeOD): δ 35.0, 41.3, 69.9, 115.0, 116.8, 118.8, 125.9, 127.3, 127.6, 128.1, 128.1, 128.5, 136.2, 136.4, 136.7, 139.1, 143.4, 159.3, 167.8.

(E)-3-(3-((3-methoxybenzyl)oxy)-5-(phenethylcarbamoyl)phenyl)acrylic acid (59b): Following the general procedure B the title compound was obtained as a white solid (10 mg, 0.02 mmol, 38%).

Rf: 0.2 (DCM:MeOH, 20: 1). 1H NMR (400 MHz; CDC13): δ 2.93 (2H, t, J = 7.0 Hz, CH2), 3.61 (2H, t, J = 6.0 Hz, CH2), 3.81 (3H, s, CH3), 5.15 (2H, s, CH2), 6.55 (1H, d, J = 15.9 Hz, CH), 6.89 (1H, dd, Jl = 2.1 Hz, J2 = 8.0 Hz, ArCH), 7.03 - 7.05 (2H, m, ArCH), 7.19 - 7.33 (6H, m, ArCH), 7.37 (1H, s, ArCH), 7.44 (1H, s, ArCH), 7.58 (1H, s, ArCH), 7.61 (1H, d, J = 16.0 Hz, CH). 13C NMR (100 MHz; CDC13): δ 35.0, 41.3, 54.2, 69.7, 112.6, 113.1, 114.9, 116.7, 118.7, 119.3, 125.9, 128.1, 128.5, 129.2, 136.3, 136.4, 138.2, 139.1, 142.7, 159.2, 159.9, 167.8. It is contemplated that any embodiment discussed in this specification can be implemented with respect to any method, kit, reagent, or composition of the invention, and vice versa. Furthermore, compositions of the invention can be used to achieve methods of the invention.

It will be understood that particular embodiments described herein are shown by way of illustration and not as limitations of the invention. The principal features of this invention can be employed in various embodiments without departing from the scope of the invention. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, numerous equivalents to the specific procedures described herein. Such equivalents are considered to be within the scope of this invention and are covered by the claims.

All publications and patent applications mentioned in the specification are indicative of the level of skill of those skilled in the art to which this invention pertains. All publications and patent applications are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

The use of the word "a" or "an" when used in conjunction with the term "comprising" in the claims and/or the specification may mean "one," but it is also consistent with the meaning of "one or more," "at least one," and "one or more than one." The use of the term "or" in the claims is used to mean "and/or" unless explicitly indicated to refer to alternatives only or the alternatives are mutually exclusive, although the disclosure supports a definition that refers to only alternatives and "and/or." Throughout this application, the term "about" is used to indicate that a value includes the inherent variation of error for the device, the method being employed to determine the value, or the variation that exists among the study subjects.

As used in this specification and claim(s), the words "comprising" (and any form of comprising, such as "comprise" and "comprises"), "having" (and any form of having, such as "have" and "has"), "including" (and any form of including, such as "includes" and "include") or "containing" (and any form of containing, such as "contains" and "contain") are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

The term "or combinations thereof as used herein refers to all permutations and combinations of the listed items preceding the term. For example, "A, B, C, or combinations thereof is intended to include at least one of: A, B, C, AB, AC, BC, or ABC, and if order is important in a particular context, also BA, CA, CB, CBA, BCA, ACB, BAC, or CAB. Continuing with this example, expressly included are combinations that contain repeats of one or more item or term, such as BB, AAA, AB, BBC, AAABCCCC, CBBAAA, CABABB, and so forth. The skilled artisan will understand that typically there is no limit on the number of items or terms in any combination, unless otherwise apparent from the context. All of the compositions and/or methods disclosed and claimed herein can be made and executed without undue experimentation in light of the present disclosure. While the compositions and methods of this invention have been described in terms of preferred embodiments, it will be apparent to those of skill in the art that variations may be applied to the compositions and/or methods and in the steps or in the sequence of steps of the method described herein without departing from the concept, spirit and scope of the invention. All such similar substitutes and modifications apparent to those skilled in the art are deemed to be within the spirit, scope and concept of the invention as defined by the appended claims.

Claims

What is claimed is:

1. An aldo-keto reductase family 1, member C3 (AKR1C3) inhibitor having one of the following structures:

derivatives thereof.

2. The inhibitor of claim 1, wherein the inhibitor is Class I or IA and

, wherein Rl is:

3. The inhibitor of claim 1, wherein the inhibitor is

4. The inhibitor of claim 1, wherein the inhibitor is:

5. The inhibitor of claim 1, wherein the inhibitor is

; or , wherein R2 is:

6. The inhibitor of claim 1, wherein the inhibitor is:

7. The inhibitor of claim 1, wherein the inhibitor is:

, wherein Rl is

, and wherein R2 is:

8. The inhibitor of claim 1, wherein the inhibitor is:

, w ere n Rl s:

9. The inhibitor of claim 1, wherein the inhibitor is formulated into a therapeutic effective amount sufficient to reduce or eliminate cancer cells.

10. The inhibitor of claim 1, further comprising a chemotherapeutic agent, wherein the inhibitor and the chemotherapeutic have a synergistic effect against cancer cells.

11. The inhibitor of claim 1, further comprising providing the inhibitor in an amount that is therapeutically effective to inhibit or reduce cellular or tissue proliferation selected from prostate cancer, castration-resistant prostate cancer, breast cancer, acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (T-ALL), or a leukemia.

12. A method of modulating cellular or tissue proliferation comprising the steps of

providing a therapeutic effective amount of an inhibitor that is selective for the enzyme AKR1C3 over its isoforms wherein the compound has the formula:

derivatives thereof.

13. The method of claim 12, wherein the inhibitor is Class I or IA and

14. The method of claim 12, wherein the inhibitor is

15. The method of claim 12, wherein the inhibitor i

16. The method of claim 12, wherein the inhibitor i

; or , wherein R2 is:

17. The method of claim 12, wherein the inhibitor is:

wherein R is:

18. The method of claim 12, wherein the inhibitor is:

, wherein R3 is ; or

and wherein R2 is:

19. The method of claim 12, wherein the inhibitor is:

, wherein Rl is:

20. The method of claim 12, wherein the inhibitor is formulated into a therapeutic effective amount sufficient to reduce or eliminate cancer cells.

21. The method of claim 12, further comprising a chemotherapeutic agent, wherein the inhibitor and the chemotherapeutic have a synergistic effect against cancer cells.

22. The method of claim 12, wherein the cellular or tissue proliferation comprises prostate cancer, castration-resistant prostate cancer, breast cancer, acute myeloid leukemia (AML), T-cell acute lymphoblastic leukemia (T-ALL), or a leukemia.

23. The method of claim 12, wherein the prostate cancer and/or castrate-resistant prostate cancer, breast cancer, leukemia is resistant to chemotherapeutic agents.

24. The method of claim 12, wherein the AKR1C3 inhibitor is synergistic with a chemotherapeutic.