WO2021222738A1 - Compounds for estrogen receptor positive cancers - Google Patents

Abstract

Small molecule ERα biomodulators that kill therapy -resistant ERα positive breast, ovarian, and endometrial cancer cells are disclosed. In one embodiment, the small molecule biomodulator has increased therapeutic utility because of an increased ability to kill therapy- resistant breast cancer cells compared to BHPI and other conventional therapies (endocrine therapies, tamoxifen and fulvestrant/ICI). The small molecule biomodulators not only inhibit proliferation of the cancer cells but kills them, which prevents reactivation of tumors years later.

Description

COMPOUNDS FOR ESTROGEN RECEPTOR POSITIVE CANCERS

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of and priority to U.S. Provisional Application No. 63/018,863, filed on May 1, 2020, the contents of which are hereby incorporated herein by reference in their entirety.

BACKGROUND

[0002] Approximately 70% of breast cancers are ERα positive. Endocrine (hormonal) therapies for these tumors include aromatase inhibitors that block estrogen production. Examples of endocrine therapies include tamoxifen, which competes with estrogens for binding to ERα, and fulvestrant/Faslodex/ICI 182,780, which both competes with estrogens and promotes ERa degradation. Although effective initially, resistance sometimes develops in primary tumors and is nearly universal in the metastatic setting. Although resistance mechanisms are diverse, recent studies show that approximately 30% of these metastatic tumors harbor ERα mutations, most commonly ERαD538G and ERαY537S. There is abundant evidence that these tumors exhibit estrogen-independent proliferation and are therefore resistant to aromatase inhibitors that block estrogen production. They are also largely resistant to tamoxifen and partially resistant to fulvestrant. Notably, patients whose metastatic tumors contain the ERαD538G mutation have a 6- month shorter survival time, and those with the ERαY537S mutation have a 12-month shorter survival time, than patients whose metastatic tumors contain non-mutated wild-type ERa. Therefore, chemotherapeutic agents targeting breast cancer cells containing these mutations are urgently needed.

[0003] The pathology of ERa positive breast cancer is unusual. While 5-year survival rates are impressive, the tumors often recur 10-20 years after initial diagnosis. This is thought to be due to reactivation and proliferation of dormant breast cancer cells. Accordingly, it is especially important to actually kill the tumor cells and not allow them to remain dormant and susceptible to reactivation. Current endocrine therapies are cytostatic, not cytotoxic. Current endocrine therapies therefore do not kill residual breast cancer cells. This allows the cells to lie dormant and reactivate at a later date. Therapeutic options for these recurrent tumors are poor and mostbreast cancer deaths are in patients with ERa positive tumors.

[0004] Ovarian cancer usually presents at an advanced stage. Tumors often recur after surgery. Although 30-70% of ovarian tumors are ERa positive, and ERa expression is associated with a poor outcome, endocrine therapy is ineffective and recurrent tumors are usually treated with platinum-based chemotherapy and paclitaxel. Although initially responsive, after several cycles of treatment, tumors recur as resistant ovarian cancer, with poor therapeutic options. More than half of ovarian cancer patients die within five years. In ovarian cancer, a common mechanism for resistance to paclitaxel and other chemotherapy agents is multidrug resistance: energy dependent drug efflux caused by overexpression of ATP-dependent efflux pumps, especially Multidrug Resistance Protein 1 (MDRl)/P-gly coprotein/ ABCB1. Despite intensive efforts, effective non-toxic MDRl inhibitors have remained elusive. Furthermore, although many cancers of the uterine endometrium are ERa positive, current endocrine therapies work poorly.

[0005] Accordingly, new small molecule therapeutic agents that are cytotoxic, and not merely cytostatic, are urgently needed to provide more efficacious cancer therapy.

SUMMARY

[0006] This disclosure provides small molecule therapeutic compounds with greatly increased therapeutic potential compared to known therapeutic compounds. The compounds display an improved ability to actually kill cancer cells, including therapy-resistant cancer cells. The therapy- resistant cancer cells can include breast cancer cells, ovarian cancer cells, and endometrial cancer cells. To prevent cancer recurrence, it is critical to destroy the entire population of growing and dormant therapy-resistant cancer cells. In various embodiments, this disclosure provides therapeutic compounds that, compared to BHPI and to endocrine therapies such as tamoxifen and fulvestrant, possess significantly increased ability to kill cancer cells, and thus, dramatically increased therapeutic potential. One example of such compounds, ErSO(OH), has greatly increased ability to kill breast cancer cells and therefore shows dramatically increased therapeutic potential. [0007] In one embodiment, this disclosure provides a compound of Formula (I):

or a salt or solvate thereof; wherein

R¹ is halo, -OR^A, -SR^A, -N(R^A)2, alkyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl;

R², R³ and R⁴ are each independently H, halo, -OR^A, -SR^A, -N(R^A)2, alkyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl;

A¹, A² and A³ are each independently H, OH, halo, or alkyl;

G¹ is halo, -OR^B, -SR^B, -S(=O)₂R^B, or alkyl;

G² is halo, -OR^c, -SR^C, -S(=O)₂R^c, or alkyl;

G³ is halo, -OR^w, -SR^W, or -S(=O)₂R^w;

X and Z are each independently O, S, or NR°; and

R^a, R^b, R^c, R^D and R^w are each independently H or alkyl; wherein each alkyl, cycloalkyl, heterocyclyl, aryl, and heteroaryl is optionally substituted with one or more substituents. For example, alkyl substituted with three halo groups provides a trihaloalkyl such as a trifluorom ethyl. Accordingly, any alkyl group of Formula (I) can be a trifluorom ethyl group.

[0008] Compounds of the formulas described herein can bind to the alpha estrogen receptor (ERa) and kill or inhibit the growth of cancer cells by hyperactivation of the unfolded protein response (UPR) in the endoplasmic reticulum. In various embodiments, the compound of Formula (I) is cytotoxic. Accordingly, this disclosure provides a method of treating a cancer comprising administering to an ERa positive cancer subject in need thereof a therapeutically effective amount of a compound described herein, thereby treating the cancer in the subject. In some embodiments, provided is a method of treating and/or preventing a cancer comprising administering to an ERa positive cancer subject in need thereof a therapeutically effective amount of a compound described herein, thereby treating and/or preventing the cancer in the subject. In some embodiments of the foregoing, the cancer can be for example, breast cancer, ovarian cancer, uterine cancer, cervical carcinoma, endometrial cancer, lung cancer, pancreatic cancer, prostate cancer, or colon cancer.

[0009] The invention provides novel compounds of Formulas I-V, intermediates for the synthesis of compounds of Formulas I-V, as well as methods of preparing compounds of Formulas I-V. The invention also provides compounds of Formulas I-V that are useful as intermediates for the synthesis of other useful compounds. The invention provides for the use ofcompounds of Formulas I-V for the manufacture of medicaments useful for the treatment of cancer in a mammal, such as a human. The medicament can include a pharmaceutically acceptable diluent, excipient, or carrier.

DETAILED DESCRIPTION

[0010] Cancer cells can remain quiescent for extended periods of time and then reactivate. It is therefore desirable to kill the tumor cells, not merely to prevent them from proliferating. This disclosure provides therapeutic compounds, including cytotoxic compounds, and assays for testing compounds for the ability to kill cancer cells, including therapy-resistant breast cancercells. Provided herein are new compounds that are more effective than BHPI in killing breastcancer cells expressing both wild type estrogen receptor a (ERa) and ERa mutations that are common in metastatic breast cancer. These mutations are associated with resistance to current breast cancer therapies. Also provided herein are compounds active against ovarian cancer cells, uterine cancer cells, and other cancer cells that are ERa positive.

[0011] The compound BHPI, illustrated above, is a known anticancer drug. The compounds described herein share an oxindole core with BHPI but were surprisingly discovered to have vastly different therapeutic properties. Various endocrine therapies such as BHPI, the 7- trifluormethyl BHPI derivative 01-15, fulvestrant, and tamoxifen merely slow cancer cell growth, i.e., they are cytostatic. Conversely, it was surprisingly discovered that ErSO(OH) iscytotoxic. ErSO(OH) was identified by its distinct cytotoxicity profile and ability to quantitatively kill cancer cells, and therefore will be an effective therapy for treating tumors.

Definitions

[0012] The following definitions are included to provide a clear and consistent understanding of the specification and claims. As used herein, the recited terms have the following meanings. All other terms and phrases used in this specification have their ordinary meanings as one of skill in the art would understand. Such ordinary meanings may be obtained by reference to technical dictionaries, such as Hawley ’s Condensed Chemical Dictionary 14^th Edition, by R. J. Lewis, John Wiley & Sons, New York, N.Y., 2001.

[0013] References in the specification to "one embodiment", "an embodiment", etc., indicate thatthe embodiment described may include a particular aspect, feature, structure, moiety, or characteristic, but not every embodiment necessarily includes that aspect, feature, structure, moiety, or characteristic. Moreover, such phrases may, but do not necessarily, refer to the sameembodiment referred to in other portions of the specification. Further, when a particular aspect, feature, structure, moiety, or characteristic is described in connection with an embodiment, it is within the knowledge of one skilled in the art to affect or connect such aspect, feature, structure, moiety, or characteristic with other embodiments, whether or not explicitly described.

[0014] The singular forms "a," "an," and "the" include plural reference unless the context clearlydictates otherwise. Thus, for example, a reference to "a compound" includes a plurality of such compounds, so that a compound X includes a plurality of compounds X. It is further noted that the claims may be drafted to exclude any optional element. As such, this statement is intended to serve as antecedent basis for the use of exclusive terminology, such as "solely," "only," and the like, in connection with any element described herein, and/or the recitation of claim elements oruse of "negative" limitations. [0015] The term "and/or" means any one of the items, any combination of the items, or all of theitems with which this term is associated. The phrases "one or more" and "at least one" are readily understood by one of skill in the art, particularly when read in context of its usage. For example, the phrase can mean one, two, three, four, five, six, ten, 100, or any upper limit approximately 10, 100, or 1000 times higher than a recited lower limit. For example, one or more substituents on a phenyl ring refers to one to five substituents on the ring.

[0016] As will be understood by the skilled artisan, all numbers, including those expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth, are approximations and are understood as being optionally modified in all instances by the term"about." These values can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings of the descriptions herein. It is also understood thatsuch values inherently contain variability necessarily resulting from the standard deviations found in their respective testing measurements. When values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value without the modifier "about" also forms a further aspect.

[0017] The terms "about" and "approximately" are used interchangeably. Both terms can refer to a variation of ± 5%, ± 10%, ± 20%, or ± 25% of the value specified. For example, in some variations, "about 50" percent can in some embodiments carry a variation from 45 to 55 percent, or as otherwise defined by a particular claim. For integer ranges, the term "about" can include one or two integers greater than and/or less than a recited integer at each end of the range. Unless indicated otherwise herein, the terms "about" and "approximately" are intended to include values, e.g., weight percentages, proximate to the recited range that are equivalent in terms of the functionality of the individual ingredient, composition, or embodiment. The terms "about" and "approximately" can also modify the endpoints of a recited range as discussed above in this paragraph.

[0018] As will be understood by one skilled in the art, for any and all purposes, particularly in terms of providing a written description, all ranges recited herein also encompass any and all possible sub-ranges and combinations of sub-ranges thereof, as well as the individual values making up the range, particularly integer values. It is therefore understood that each unit between two particular units are also disclosed. For example, if 10 to 15 is disclosed, then 11, 12, 13, and 14 are also disclosed, individually, and as part of a range. A recited range (e.g., weight percentages or carbon groups) includes each specific value, integer, decimal, or identity within the range. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, or tenths. As a non-limiting example, each range discussed herein can be readily broken down intoa lower third, middle third and upper third, etc. As will also be understood by one skilled in the art, all language such as "up to", "at least", "greater than", "less than", "more than", "or more", and the like, include the number recited and such terms refer to ranges that can be subsequently broken down into sub-ranges as discussed above. In the same manner, all ratios recited herein also include all sub-ratios falling within the broader ratio. Accordingly, specific values recited for radicals, substituents, and ranges, are for illustration only; they do not exclude other defmedvalues or other values within defined ranges for radicals and substituents. It will be further understood that the endpoints of each of the ranges are significant both in relation to the otherendpoint, and independently of the other endpoint.

[0019] This disclosure provides ranges, limits, and deviations to variables such as volume, mass, percentages, ratios, etc. It is understood by an ordinary person skilled in the art that a range, such as “number 1” to “number 2”, implies a continuous range of numbers that includes the whole numbers and fractional numbers. For example, 1 to 10 means 1, 2, 3, 4, 5, ... 9, 10. It also means 1.0, 1.1, 1.2. 1.3, ..., 9.8, 9.9, 10.0, and also means 1.01, 1.02, 1.03, and so on. If the variable disclosed is a number less than “number 10”, it implies a continuous range that includes whole numbers and fractional numbers less than number 10, as discussed above. Similarly, if the variable disclosed is a number greater than “number 10”, it implies a continuous range that includes whole numbers and fractional numbers greater than number 10. These ranges can bemodified by the term “about”, whose meaning has been described above.

[0020] One skilled in the art will also readily recognize that where members are grouped together in a common manner, such as in a Markush group, the invention encompasses not only the entire group listed as a whole, but each member of the group individually and all possible subgroups of the main group. Additionally, for all purposes, the invention encompasses not onlythe main group, but also the main group absent one or more of the group members. The invention therefore envisages the explicit exclusion of any one or more of members of a recited group. Accordingly, provisos may apply to any of the disclosed categories or embodiments whereby any one or more of the recited elements, species, or embodiments, may be excluded from such categories or embodiments, for example, for use in an explicit negative limitation. [0021] In some embodiments, the term "contacting" refers to the act of touching, making contact, or of bringing to immediate or close proximity, including at the cellular or molecular level, for example, to bringabout a physiological reaction, a chemical reaction, or a physical change, e.g., in a solution, in a reaction mixture, in vitro , or in vivo.

[0022] In some embodiments, an "effective amount" refers to an amount effective to treat a disease, disorder, and/or condition, or to bring about a recited effect. For example, an effective amount can be an amounteffective to reduce the progression or severity of the condition or symptoms being treated.

[0023] Determination of a therapeutically effective amount is well within the capacity of persons skilled in the art. In certain embodiments, the term "effective amount" is intended to include an amount of a compound described herein, or an amount of a combination of compounds described herein, e.g., that iseffective to treat or prevent a disease or disorder, or to treat the symptoms of the disease or disorder, in a host. Thus, an "effective amount" generally means an amount that provides the desired effect.

[0024] Alternatively, in other embodiments, the terms "effective amount" or "therapeutically effective amount," as usedherein, refer to a sufficient amount of an agent or a composition or combination of compositions being administered which will relieve to some extent one or more of the symptoms of the diseaseor condition being treated. The result can be reduction and/or alleviation of the signs, symptoms, or causes of a disease, or any other desired alteration of a biological system. For example, an "effective amount" for therapeutic uses is the amount of the composition comprising a compoundas disclosed herein required to provide a clinically significant decrease in disease symptoms. An appropriate "effective" amount in any individual case may be determined using techniques, such as a dose escalation study. The dose could be administered in one or more administrations. However, the precise determination of what would be considered an effective dose may be basedon factors individual to each patient, including, but not limited to, the patient's age, size, type or extent of disease, stage of the disease, route of administration of the compositions, the type or extent of supplemental therapy used, ongoing disease process and type of treatment desired (e.g., aggressive vs. conventional treatment).

[0025] In some embodiments, the terms "treating", "treat" and "treatment" include (i) inhibiting the disease, pathologic ormedical condition or arresting its development; (ii) relieving the disease, pathologic or medical condition; and/or (iii) diminishing symptoms associated with the disease, pathologic or medical condition. Thus, the terms "treat", "treatment", and "treating" can include lowering, stopping, or reversing the progression or severity of the condition or symptoms being treated. As such, the term "treatment" can include medical and/or therapeutic administration, as appropriate.

[0026] In some embodiments, as used herein, "subject" or “patient” means an individual having symptoms of, or at riskfor, a disease or other malignancy. A patient may be human or non-human and may include, for example, animal strains or species used as “model systems” for research purposes, such a mousemodel as described herein. Likewise, patient may include either adults or juveniles ( e.g ., children). Moreover, patient may mean any living organism, preferably in one variation, a mammal (e.g., human or non-human) that may benefit from the administration of compositions contemplated herein. Examples of mammals include, but are not limited to, any member of the Mammalian class: humans, non-human primates such as chimpanzees, and other apes and monkey species; farm animals such as cattle, horses, sheep, goats, swine; domestic animals such as rabbits, dogs, andcats; laboratory animals including rodents, such as rats, mice and guinea pigs, and the like. Examples of non-mammals include, but are not limited to, birds, fish and the like. In one embodiment of the methods provided herein, the mammal is a human.

[0027] In some embodiments, as used herein, the terms “providing”, “administering,” “introducing,” are used interchangeably herein and refer to the placement of a compound of the disclosure into a subjectby a method or route that results in at least partial localization of the compound to a desired site. The compound can be administered by any appropriate route that results in delivery to a desired location in the subject.

[0028] In some embodiments, the compounds and compositions described herein may be administered with additional compositions to prolong stability and activity of the compositions, or in combination with othertherapeutic drugs.

[0029] In some embodiments, the terms "inhibit", "inhibiting", and "inhibition" refer to the slowing, halting, or reversing the growth or progression of a disease, infection, condition, or group of cells. The inhibition can be greater than about 20%, 40%, 60%, 80%, 90%, 95%, or 99%, for example, compared to the growth or progression that occurs in the absence of the treatment or contacting. [0030] In some embodiments, the term “substantially” as used herein, is a broad term and is used in its ordinary sense, including, without limitation, being largely but not necessarily wholly that which is specified. For example, the term could refer to a numerical value that may not be 100% the full numerical value. The full numerical value may be less by about 1%, about 2%, about 3%, about 4%, about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 15%, or about 20%.

[0031] Wherever the term “comprising” is used herein, options are contemplated wherein the terms “consisting of’ or “consisting essentially of’ are used instead. As used herein, “comprising” is synonymous with "including," "containing," or "characterized by," and is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. Asused herein, "consisting of excludes any element, step, or ingredient not specified in the aspect element. As used herein, "consisting essentially of does not exclude materials or steps that do not materially affect the basic and novel characteristics of the aspect. In each instance herein anyof the terms "comprising", "consisting essentially of and "consisting of may be replaced with either of the other two terms. The disclosure illustratively described herein may be suitably practiced in the absence of any element or elements, limitation, or limitations not specifically disclosed herein.

[0032] The term "halo" or "halide" refers to fluoro, chloro, bromo, or iodo. Similarly, the term "halogen" refers to fluorine, chlorine, bromine, and iodine.

[0033] In some embodiments, The term "alkyl" refers to a branched or unbranched hydrocarbon having, for example, from 1-20 carbon atoms, and often 1-12, 1-10, 1-8, 1-6, or 1-4 carbon atoms.

In some variations, as used herein, the term “alkyl” also encompasses a “cycloalkyl”, defined below. Examples include, but are not limited to, methyl, ethyl, 1 -propyl, 2-propyl (Ao-propyl), 1 -butyl, 2- methyl-1 -propyl {isobutyl), 2-butyl (sec-butyl), 2-methyl-2-propyl (/-butyl), 1 -pentyl, 2-pentyl, 3- pentyl, 2-methyl-2-butyl, 3 -methyl-2 -butyl, 3 -methyl- 1 -butyl, 2-methyl- 1 -butyl, 1 -hexyl, 2-hexyl, 3- hexyl, 2-methyl-2- pentyl, 3-methyl-2-pentyl, 4-methyl-2-pentyl, 3 -methyl-3 -pentyl, 2-m ethyl-3 - pentyl, 2,3-dimethyl-2-butyl, 3,3-dimethyl-2-butyl, hexyl, octyl, decyl, dodecyl, and the like. The alkyl can be unsubstituted or substituted, for example, with a substituent described below or otherwise described herein. The alkyl can also be optionally partially or fully unsaturated. As such, the recitation of an alkyl group can include an alkenyl group or an alkynyl group. The alkyl can be a monovalent hydrocarbon radical, as described and exemplified above, or it can be a divalent hydrocarbon radical (i.e., an alkylene). [0034] In some embodiments, an alkylene is an alkyl group having two free valences at carbon or two different carbonatoms of a carbon chain. Similarly, alkenylene and alkynylene are respectively an alkene and analkyne having two free valences at two different carbon atoms.

[0035] In some embodiments, the term "cycloalkyl" refers to cyclic alkyl groups of, for example, from 3 to 10 carbon atoms having a single cyclic ring or multiple condensed rings. Cycloalkyl groups include, by way of example, single ring structures such as cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl, and the like, or multiple ring structures such as adamantyl, and the like. The cycloalkyl can be unsubstituted or substituted. The cycloalkyl group can be monovalent or divalent and can be optionally substituted as described for alkyl groups. The cycloalkyl group can optionally include one or more cites of unsaturation, for example, the cycloalkyl group can include one or more carbon-carbon double bonds, such as, for example, 1- cyclopent-l-enyl, l-cyclopent-2-enyl, 1- cyclopent-3-enyl, cyclohexyl, 1 -cyclohex- 1-enyl, 1- cyclohex-2-enyl, 1 -cyclohex-3 -enyl, and the like.

[0036] In some embodiments, the term "heterocycloalkyl" or “heterocyclyl” refers to a saturated or partially saturated monocyclic, bicyclic, or polycyclic ring containing at least one heteroatom selected from nitrogen, sulfur, oxygen, preferably, in certain variations, from 1 to 3 heteroatoms in at least one ring. Each ring ispreferably from 3 to 10 membered, more preferably 4 to 7 membered. Examples of suitable heterocycloalkyl substituents include pyrrolidyl, tetrahydrofuryl, tetrahydrothiofuranyl, piperidyl, piperazyl, tetrahydropyranyl, morpholino, 1,3-diazapane, 1,4- diazapane, 1,4- oxazepane, and 1,4-oxathiapane. The group may be a terminal group or a bridging group.

[0037] In some embodiments, the term "aromatic" refers to either an aryl or heteroaryl group or substituent described herein. Additionally, an aromatic moiety may be a bisaromatic moiety, a trisaromatic moiety, and so on. A bisaromatic moiety has a single bond between two aromatic moieties such as, but not limited to, biphenyl, or bipyridine. Similarly, a trisaromatic moiety has a single bond between each aromaticmoiety.

[0038] In some embodiments, the term "aryl" refers to an aromatic hydrocarbon group derived from the removal of at least one hydrogen atom from a single carbon atom of a parent aromatic ring system. The radical attachment site can be at a saturated or unsaturated carbon atom of the parent ring system. The aryl group can have from 6 to 30 carbon atoms, for example, about 6-10 carbon atoms. The arylgroup can have a single ring (e.g., phenyl) or multiple condensed (fused) rings, wherein at least one ring is aromatic (e.g., naphthyl, dihydrophenanthrenyl, fluorenyl, or anthryl). Typical aryl groups include, but are not limited to, radicals derived from benzene, naphthalene, anthracene, biphenyl, and the like. The aryl can be unsubstituted or optionally substituted with a substituent described below.

[0039] In some embodiments, the term "heteroaryl" refers to a monocyclic, bicyclic, or tricyclic ring system containingone, two, or three aromatic rings and containing at least one nitrogen, oxygen, or sulfur atom in an aromatic ring. The heteroaryl can be unsubstituted or substituted, for example, with one or more, and in particular one to three, substituents, as described in the definition of "substituted". Typical heteroaryl groups contain 2-20 carbon atoms in the ring skeleton in addition to the one ormore heteroatoms, wherein the ring skeleton comprises a 5-membered ring, a 6-membered ring, two 5-membered rings, two 6-membered rings, or a 5-membered ring fused to a 6-membered ring. Examples of heteroaryl groups include, but are not limited to, 2H-pyrrolyl, 3H- indolyl, 4H-quinolizinyl, acridinyl, benzo[b]thienyl, benzothiazolyl, b-carbolinyl, carbazolyl, chromenyl, cinnolinyl, dibenzo[b,d]furanyl, furazanyl, furyl, imidazolyl, imidizolyl, indazolyl, indolisinyl, indolyl, isobenzofuranyl, isoindolyl, isoquinolyl, isothiazolyl, isoxazolyl, naphthyridinyl, oxazolyl, perimidinyl, phenanthridinyl, phenanthrolinyl, phenarsazinyl, phenazinyl, phenothiazinyl, phenoxathiinyl, phenoxazinyl, phthalazinyl, pteridinyl, purinyl, pyranyl, pyrazinyl, pyrazolyl, pyridazinyl, pyridyl, pyrimidinyl, pyrrolyl, quinazolinyl, quinolyl, quinoxalinyl, thiadiazolyl, thianthrenyl, thiazolyl, thienyl, triazolyl, tetrazolyl, and xanthenyl. In one embodiment the term "heteroaryl" denotes a monocyclic aromatic ring containing five or six ring atoms containing carbon and 1, 2, 3, or 4 heteroatoms independently selected from non- peroxide oxygen, sulfur, and N(Z) wherein Z is absent or is H, O, alkyl, aryl, or (C₁-C₆)alkylaryl. In some embodiments, heteroaryl denotes an ortho-fused bicyclic heterocycle of about eight to ten ring atoms derived therefrom, particularly a benz-derivative or one derived by fusing apropylene, trimethylene, or tetramethylene diradical thereto.

[0040] As used herein, the term "substituted" or “substituent” is intended to indicate that one or more (for example, in various embodiments, 1-10; in other embodiments, 1-6; in some embodiments 1, 2, 3, 4, or 5; in certain embodiments, 1, 2, or 3; and in other embodiments, 1 or 2) hydrogens on the group indicated in the expression using “substituted” (or “substituent”) is replaced with a selection from the indicated group(s), or with a suitable group known to those of skill in the art, provided that the indicated atom’s normal valency is not exceeded, and that the substitution results in a stable compound. Suitable indicated groups include, e.g., alkyl, alkenyl, alkynyl, alkoxy, haloalkyl, hydroxyalkyl, aryl, heteroaryl, heterocyclyl, cycloalkyl, alkanoyl, alkoxycarbonyl, amino, alkylamino, dialkylamino, carboxyalkyl, alkylthio, alkylsulfmyl, and alkyl sulfonyl. Substituents of the indicated groups can be those recited in a specific list of substituents described herein, or as one of skill in the art would recognize, can be one or moresubstituents selected from alkyl, alkenyl, alkynyl, alkoxy, halo, haloalkyl, hydroxy, hydroxyalkyl, aryl, heteroaryl, heterocycle, cycloalkyl, alkanoyl, alkoxycarbonyl, amino, alkylamino, dialkylamino, trifluoromethylthio, difluoromethyl, acylamino, nitro, trifluoromethyl,trifluoromethoxy, carboxy, carboxyalkyl, keto, thioxo, alkylthio, alkylsulfmyl, alkylsulfonyl, andcyano. Suitable substituents of indicated groups can be bonded to a substituted carbon atom include F, Cl, Br, I, OR', 0C(0)N(R')₂, CN, CF₃, OCF₃, R', O, S, C(O), S(O), methylenedioxy, ethylenedioxy, N(R')2, SR', SOR', SO₂R', S0₂N(R')₂, SO₃R', C(O)R', C(O)C(O)R, C(O)CH₂C(O)R', C(S)R', C(0)0R', OC(O)R', C(O)N(R)2, 0C(0)N(R')2, C(S)N(R)2, (CH₂)O-₂NHC(0)R', N(R')N(R')C(O)R', N(R')N(R)C(O)OR', N(R')N(R)CON(R')2, N(R)S0₂R, N(R)SO₂N(R')2, N(R')C(0)0R, N(R)C(0)R', N(R')C(S)R', N(R)C(O)N(R')2, N(R')C(S)N(R')2, N(COR')COR', N(OR)R, C(=NH)N(R)₂, C(O)N(OR')R', or C(=NOR')R' wherein R’ can be hydrogen or a carbon-based moiety (e.g., (Ci-Ce)alkyl), and wherein the carbon-based moiety can itself be further substituted. When a substituent is monovalent, such as, for example, F or Cl, it is bonded to the atom it is substituting by a single bond. When a substituent is divalent, such as O, it is bonded to the atom it is substituting by a double bond; for example, a carbon atom substituted with O forms a carbonyl group, C=0.

[0041] Stereochemical definitions and conventions used herein generally follow S.P. Parker,

Ed., McGraw-Hill Dictionary of Chemical Terms (1984) McGraw-Hill Book Company, New York; and Eliel, E. and Wilen, S., “Stereochemistry of Organic Compounds”, John Wiley & Sons, Inc., New York, 1994. The compounds of the invention may contain asymmetric or chiral centers, and therefore exist in different stereoisomeric forms. It is intended that all stereoisomeric forms of the compounds of the invention, including but not limited to, diastereomers, enantiomers and atropisomers, as well as mixtures thereof, such as racemic mixtures, which form part of the present invention. Many organic compounds exist in optically active forms, i.e., they have the ability to rotate the plane of plane-polarized light. In describing an optically active compound, the prefixes D and L, or R and S. are used to denote the absolute configuration of the molecule about its chiral center(s). The prefixes d and 1 or (+) and (-) are employed to designate the sign of rotation of plane- polarized light by the compound, with (-) or 1 meaning that the compound is levorotatory. A compound prefixed with (+) or d is dextrorotatory. For a given chemical structure, these stereoisomers are identical except that they are mirror images of one another. A specific stereoisomer may also be referred to as an enantiomer, and a mixture of such isomers is often called an enantiomeric mixture. A 50:50 mixture of enantiomers is referred to as a racemic mixture or a racemate (defined below), which may occur where there has been no stereoselection or stereospecificity in a chemical reaction or process.

[0042] In some embodiments, the terms “racemic mixture” and “racemate” refer to an equimolar mixture of twoenantiomeric species, devoid of optical activity.

[0043] In some embodiments, the term “enantiomerically enriched” (“ee”) as used herein refers to mixtures that haveone enantiomer present to a greater extent than another. Reactions that provide one enantiomer present to a greater extent than another would therefore be “enantioselective” (or demonstrate “enantioselectivity”). In one embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having at least about 2% ee; in another embodiment of the invention, the term“enantiomerically enriched” refers to a mixture having at least about 5% ee; in another embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having at least about 20%; in another embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having at least about 50%; in another embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having at least about 80%; in another embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having atleast about 90%; in another embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having at least about 95%; in another embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having at least about 98%; in another embodiment of the invention, the term “enantiomerically enriched” refers to a mixture having at least about 99%. The term “enantiomerically enriched” includes enantiomerically pure mixtures which are mixtures that are substantially free of the species of the opposite optical activity or oneenantiomer is present in very low quantities, for example, 0.01%, 0.001% or 0.0001%.

[0044] The term “IC₅₀” is generally defined as the concentration required to kill 50% of the cells in 24 hours. [0045] In some embodiments, as used herein, the name "ErSO(OH)" refers to the active compound (ri)-ErSO(OH), whereas the inactive compound is specifically referred to as (R)- ErSO(OH) and the racemic mixture is specifically referred to as (R X)-ErSO(OH),

Embodiments of the Invention

[0046] This disclosure provides various embodiments of a compound of Formula (I) or (IB):

or a salt or solvate thereof; wherein

R¹ is halo, -OR^A, -SR^A, -N(R^A)2, alkyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl;

R², R³ and R⁴ are each independently H, halo, -OR^A, -SR^A, -N(R^A)2, alkyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl;

A¹, A² and A³ are each independently H, OH, halo, or alkyl;

G¹ is halo, -OR^B, -SR^B, -S(=0)₂R^B, or alkyl;

G² is halo, -OR^c, -SR^C, -S(=0)2R^C, or alkyl;

G³ is halo, -OR^w, -SR^W, -S(=0)₂R^w, or alkyl;

X and Z are each independently O, S, or NR°; and

R^a, R^b, R^c, R^D and R^w are each independently H or alkyl;wherein each alkyl, cycloalkyl, heterocyclyl, aryl, and heteroaryl is optionally substitutedwith one or more substituents, and wherein when G¹, G², or G³ is -OR^B, -OR^c, or -OR^w, respectively, R^B, R^c, and R^w each independently can be an oxygen protecting group.

[0047] In each formula described herein, when a variable, such as any one of R³-R⁴, A¹- A³, G¹- G³, R^a, R^b, R^c, R^d, or R^w, is alkyl, the alkyl is optionally substituted with one or more substituents, such as one or more of the substituents described in the definition of substituents herein. Alkyl optionally substituted with one or more substituents can be, for example, alkyl substituted with one to six substituents, one to five substituents, one to four substituents, one tothree substituents, one or two substituents, or one substituent. Alkyl optionally substituted with one or more substituents includes, for example, in some variations, halo- substituted alkyl groups such as CF3, CHF2,CH2F, CH₂CF₃, CF₂CH₃, or CF₂CF₃.

[0048] In one specific embodiment, R¹ is CF₃. In one specific embodiment, G¹ is CF₃. In another specific embodiment, G¹ is OCF₃. In one specific embodiment, G² is CF3. In another specific embodiment, G² is OCF₃. In one specific embodiment, G³ is CF3. In another specific embodiment, G³ is OCF₃.

[0049] In some embodiments, G¹ is OR^B. In certain embodiments, R^B is H or -(Ci-C6)alkyl. In some embodiments, R^B is -(C₁)alkyl optionally substituted with one to three substituents. In various embodiments, R^B is -(C₁)alkyl substituted with one to three halo substituents. In one specific embodiment, G¹ is OH. In another specific embodiment, G¹ is methyl or trifluorom ethyl.

[0050] In some embodiments, G² is OR^c. In certain embodiments, R^c is H or -(Ci-C6)alkyl. In some embodiments, R^c is -(C₁)alkyl optionally substituted with one to three substituents. In various embodiments, R^c is -(C₁)alkyl substituted with one to three halo substituents. In one specific embodiment, G² is OH. In another specific embodiment, G² is methyl or trifluorom ethyl.

[0051] In some embodiments, G³ is OR^w. In certain embodiments, R^w is H or -(Ci-C6)alkyl. In some embodiments, R^w is -(C₁)alkyl optionally substituted with one to three substituents. In various embodiments, R^w is -(C₁)alkyl substituted with one to three halo substituents. In one specific embodiment, G³ is OH. In another specific embodiment, G³ is methyl or trifluoromethyl.

[0052] In some embodiments, R^A, R^B, R^c and R° are each independently H or -(Ci-C6)alkyl. In certain embodiments, R¹, R², R³ and R⁴ are each independently H, halo, or -(Ci-C6)alkyl. In various embodiments, A¹, A², and A³ are each independently H or halo, and G¹ is -OR^B, and Gris -OR^c.

[0053] In some embodiments, X is NR° and Z is O. In one particular embodiment, R° is H.In various embodiments, R^A, R^B, R^c, R°, R^w, R¹, R², R³ and R⁴ are each independently -(Ci-Ce)alkyl, -(C2-C6)alkyl, -(C3-C6)alkyl, or -(C3-C6)cycloalkyl. In some embodiments, when present, at least one -(Ci-Ce)alkyl, -(C2-C6)alkyl, -(C3-C6)alkyl, or -(C3-C6)cycloalkyl is substituted with one or more halo. In certain specific embodiments, -(Ci- C6)alkyl is trifluoromethyl.

[0054] In various embodiments, R¹ is CH3, CH2CH3, CF3, CHF2, CH2CF3, CF2CH3, or CF2CF3. [0055] In some embodiments, G¹ is OH, G² is -OR^c, and R^c is H, CH3, CH2CH3, CF3, CHF2, CH₂CF3,CF₂CH3, or CF2CF3.

[0056] In one embodiment, R¹ is CH3 or CF3, R² is H, F, or Cl, R³ and R⁴ are H, X is NH, Z is 0,A⁴-A³ are H, G¹ is OH, G² is OCF₃, and G³ is OH.

[0057] In some embodiments, the compound of Formula (I) is the fV)-enantiomer, In other embodiments, the compound of Formula (I) is the (//(-enantiomer,

[0058] In further embodiments, the compound of Formula (I) is a compound of Formula (II) or Formula (III):

[0059] In yet further embodiments, the compound of Formula (I), (II), or (III) is a compound of Formula (IV):

wherein G² is -OR^c, and R^c and R¹ are each independently alkyl or cycloalkyl, wherein the alkyl and cycloalkyl are optionally substituted with one or more halo groups.

[0060] In another embodiment, the compound of Formula (I), (II), (III), or (IV) is a compound of Formula (V):

wherein

R¹ is Me, Et, CF₃, or CH2CF3;

R² is H, Me, Et, CF3, CH2CF3, F, Cl, or OH;

G¹ is F, Me, CF₃, OCF₃, OH, or OP;

G² is F, Me, CF₃, OCF₃, OH, or OP;

G³ is F, Me, CF₃, OCF₃, OH, or OP; and

P, when present, is an oxygen protecting group.

[0061] In one specific embodiment, R¹ is CF3, R² is H, G¹ is OH, G² is OCF₃, and G³ is OH. In another embodiment, at least one of G¹, G², and G³ is OP wherein P is an oxygen protecting group selected from allyl, benzyl, thiobenzyl, acetyl, chloroacetyl, trifluoroacetyl, phenacyl, methyl methoxy, PEG (-(OCH2CH2)nOH or (-(OCH2CH2)nO-alkyl wherein n is 2 to about 1,000), an amino acid, and a silyl ether (e.g., trimethyl silyl (TMS), /-butyl di methyl si lyl (TBS), or/-butyl- diphenylsilyl (TBDPS)), or each of G¹ and G³ is OP and their OP groups taken together form a benzylidene group.

[0062] In various other embodiments, one or more hydrogen atoms is deuterium or tritium, one or more carbon atoms is a carbon isotope, or a combination thereof.

[0063] In some embodiments, the compound of Formula (I), (II), (III), or (IV) is a compound selectedfrom (R)- or fV)-(F), (G), (H), (K), (J), or (X):

[0064] In further embodiments, the compound of Formula (I), (II), (III), or (IV) is the (R)- or fV)-compound selected from:

wherein G² is OH, SH, Me, CF3, OMe, or OCF₃.

[0065] In some embodiments, the compound is levorotatory. In other embodiments, the compound is dextrorotatory. In a specific embodiment, the compound is (S)-ErSO(OH). In one embodiment, the compound is (L')-3 -(3, 4-dihydroxyphenyl )-3-(4-(trifluorom ethoxy )phenyl)-7- (trifluoromethyl)indolin-2-one. In another embodiments, the compound is (i?)-3-(3,4- dihydroxyphenyl)-3-(4-(trifluoromethoxy)phenyl)-7-(trifluoromethyl)indolin-2-one.

[0066] The compound of Formula (I), (IB), (II), (III), (IV), or (V) (an enantiomer or racemate) can have abinding affinity for the alpha estrogen receptor (ERa) wherein the ICso of the binding affinity isless than about 500 nM. In other embodiments the ICso for ERa is about 1 pM to about 1000 nM, about 0.1 nM to about 750 nM, about 1 nM to about 250 nM, about 5 nM to about 500 nM, about 10 nM to about 5000 nM, about 10 nM to about 80 nM, or about 20 nM to about 45 nM. The compound can kill or inhibit the growth of cancer cells by hyperactivation of the unfolded protein response (UPR) in the endoplasmic reticulum. The cancer cells can be ERa positive cancer cells. In certain embodiments, the compounds are cytotoxic. In various embodiments, the cancer cells are breast cancer cells, ovarian cancer cells, or endometrial cancer cells.

[0067] This disclosure also provides a composition comprising the compound disclosed herein and a second drug. The disclosure further provides a pharmaceutical composition comprising an enantiopure or enantioenriched compound disclosed herein in combination with a pharmaceutically acceptable diluent, carrier, excipient, or buffer. In some embodiments of the pharmaceutical composition, the compound is a racemic or scalemic mixture of (i?)-ErSO(OH) and fV)-ErSO(OH), In various embodiments, the mixture is a mixture of enantiomers whereinthe mixture of enantiomers has a ratio of about 50:50, about 45:55, about 40:60, about 30:70, about 20:80, about 10:90, or about 5:95. In other embodiments of the pharmaceutical composition, the compound is OS)-ErSO(OH).

[0068] The disclosure additionally provides a method of treating a cancer comprising administering to an ERa positive cancer subject in need thereof a therapeutically effective amount of a compound disclosed herein, thereby treating the cancer in the subject. In some embodiments, the disclosure additionally provides a method of treating and/or preventing a cancer comprising administering to an ERa positive cancer subject in need thereof a therapeutically effective amount of a compound disclosed herein, thereby treating and/or preventing the cancer in the subject. In some variations, preventing a disease or condition includes delaying, deferring, hindering, slowing, retarding, and/or postponing the development of the disease or condition. The delay can be of varying lengths of time, depending on the history of the disease and/or the individual being treated. As is evident to one skilled in the art, a sufficient or significant delay can, in some variations, mean that the individual does not develop the disease or condition. In some embodiments of the foregoing, the compound kills or inhibits growth of ERa positive cancer by hyperactivation of the unfolded protein response (UPR) in the endoplasmic reticulum. In various embodiments, the ERa positive cancer is a breast cancer, ovarian cancer, uterine cancer, cervical carcinoma, or endometrial cancer.

[0069] The disclosure additionally provides a use of the compound for the treatment of an ERa positive cancer. In some embodiments, the disclosure additionally provides a use of the compound for the treatment and/or prevention of an ERapositive cancer. The ERa positive cancer can be breast cancer, ovarian cancer, uterine cancer, cervical carcinoma, or endometrial cancer. The compound can be administered orally, by injection, subcutaneously, sublingually, rectally, by infusion, intravenously, or by dermal absorption.

[0070] In some aspects, articles of manufacture are also provided herein, wherein the article of manufacture comprises a compound of the present disclosure, including, for example, a compound of formula (I), (II), (III), (IV), or (V), or any variation or embodiment thereof, or a salt of any of the foregoing, in a suitable container. Also provided herein are articles of manufacture, comprising a pharmaceutical composition comprising a compound of the present disclosure, including, for example, a compound of formula (I), (II), (III), (IV), or (V), or any variation or embodiment thereof, or a salt of any of the foregoing, and at least one pharmaceutically acceptable carrier, in a suitable container. The container may be a vial, jar, ampoule, preloaded syringe, or intravenous bag.

[0071] The present disclosure further provides kits for carrying out the methods of the invention. The kits may comprise a compound, or salt thereof, or a pharmaceutical composition, as described herein, and suitable packaging. The kits may comprise one or more containers comprising any compound, or salt thereof, or any pharmaceutical composition described elsewhere herein. In one aspect, a kit includes a compound of the disclosure, or a salt thereof, and a label and/or instructions for use of the compound in the treatment of a disease or disorder described herein. The kits may comprise a unit dosage form of the compound. In one aspect, a kit includes a pharmaceutical composition of the disclosure and a label and/or instructions for use of the pharmaceutical composition in the treatment of a disease or disorder described herein. The kits may comprise a unit dosage form of the pharmaceutical composition. [0072] In certain aspects, provided herein are kits, comprising: (i) an effective amount of a compound of formula (I), (II), (III), (IV), or (V), or any variation or embodiment thereof, or a salt of any of the foregoing; and (ii) instructions for use in treating a disease, disorder, or condition, as described elsewhere herein. Also provided herein are kits, comprising: (i) a pharmaceutical composition, comprising an effective amount of a compound of formula (I), (II), (III), (IV), or (V), or any variation or embodiment thereof, or a salt of any of the foregoing, and at least one pharmaceutically acceptable carrier; and (ii) instructions for use in treating a disease, disorder, or condition, as described elsewhere herein.

Results and Discussion

[0073] The CRISPR/Cas9 gene editing system was used to replace wild type ERa in T47D human breast cancer cells with the two most common ERa mutations seen in metastatic breast cancer, ERaY537S and ERaD538G. The resulting cell lines TYS-4 (also called TYS) and TDG-1 (also called TDG) (T47DERaY537S clone 4 and T47DERaD538G clone i) exhibitsignificant resistance to tamoxifen (the active form of tamoxifen is z-4-hydroxytamoxifen; z-OHT) and to fulvestrant/ICI 182,780.

[0074] To allow visualization of tumors harboring these mutations in live animal, clonal lines of TYS and TDG cells stably expressing firefly luciferase were isolated. Orthotopic mouse tumors containing these TYS-Luc and TYDG-Luc cells are visualized in live animals by bioluminescent imaging (BLI). Because the In Vivo Imaging System (IVIS) has a detection range of more than 10,000-fold and can be used to visualize progression of both primary tumors and metastatic tumors, BLI using IVIS is considered the most advanced way to evaluate the efficacy of new anticancer drugs in animal models. To the best of our knowledge, no other research team in auniversity, pharmaceutical, or biotechnology company has developed cell lines combining expression of the breast cancer ERa mutations and luciferase for BLI.

[0075] Unbiased high throughput screening was used for small molecules that block ERa action to identify novel ERa biomodulators. BHPI was the first generation lead small molecule to emerge from that search. BHPI is a potent first-in-class non-competitive small molecule ERa biomodulator that kills therapy-resistant ERa positive breast and endometrial cancer cells and blocks growth of ovarian cancer cells. BHPI binds at a different site on ERa than tamoxifen andfulvestrant and has a different mechanism of action. It was demonstrated that BHPI works through ERa to induce persistent lethal hyperactivation of the anticipatory pathway of activation of the unfolded protein response (UPR). In cell culture models, BHPI selectively blocks growth of cancer cells. BHPI blocked proliferation of the TYS and TDG cells expressing ERamutations identified in metastatic breast cancer.

[0076] In a mouse xenograft model of ERa positive breast cancer, at reasonable doses, BHPI stopped tumor growth and induced rapid and substantial tumor regression. In xenograft studies using TYS-Luc and TDG-Luc cells, after 4 weeks the vehicle control breast tumors had roughly quadrupled in cells. In contrast, the tumors in mice treated with BHPI exhibited 97%-99.5% regression.

[0077] In an orthotopic ovarian cancer xenograft model using OVCAR-3 cells that are highly resistant to diverse anticancer drugs, the taxane paclitaxel was ineffective. BHPI alone strongly reduced tumor growth. Notably, tumors were undetectable in mice treated with BHPI pluspaclitaxel and levels of the circulating cancer biomarker CA125 progressively declined to undetectable. In both studies, BHPI was well tolerated by the mice.

[0078] New Compounds with Ability to Kill Breast Cancer Cells. Assays were developed for compounds with an improved ability to kill cancer cells. One of the assays is based on the classical criterion for cell death, loss of membrane integrity as measured by uptake of the dye Trypan Blue. This instrument-based assay determines the percentage of cells in a population that have taken up Trypan Blue. All cells that have taken upTrypan Blue are dead. This assay is unique to the disclosed screening workflow. Although Trypan Blue uptake is universally accepted as a measure of cell death, it has not been used by others to test potential anticancer drugs. Additional assays used to evaluate cell death includefluorescence activated cell sorting (FACS) and assays based on inhibition of proliferation anddetermination of cell number, sometimes in conjunction with raptinal, a compound known to induce 100% cell death.

[0079] Through synthesis and evaluation, novel compounds that are superior to BHPI in their ability to kill breast cancer cells were identified. This led to the discovery of ErSO, a small molecule with potent anticancer efficacy with significant cancer cell selectivity even at concentrations more than 10 times higher than those needed to eradicate ERa positive breast cancer cells. Further exploration of the ErSO pharmacophore, led to our discovery of ErSO-OH, which has similar anticancer activity as compared to ErSO. [0080] Moreover, current endocrine therapy drugs tamoxifen and fulvestrant are cytostatic and showed no ability at all to kill TYS and TDG breast cancer cells. Demonstrating target specificity, even at concentrations more than 10 times higher than those that effectively kill ERapositive breast cancer cells, ERSO(OH) had no effect in several ERa negative cell lines. Also, the inactive (R) enantiomer was ineffective and not toxic in ERa positive and ERa negative celllines.

[0081] Comparison of inhibition data for racemic and purified enantiomers of ErSO(OH) and other structurally related structures are presented in Tables 1 and 2. Chemical physical properties and in-vivo toxicity of fV)-ErSO(OH) and other structurally related compounds arepresented in

Table 3

Table 1. ErSO(OH) inhibitory activity in breast cancer cells.

isocratic: 40% i-PrOH/hexanes

(R/S)- ErSO(OH) 15 min runs fSj-ErSO(OH) (R)- ErSO(OH)

(inactive)

* n = 3; 6,000 MCF-7 cells/well, 6-hour and 24-hour incubation followed by media aspiration and Alamar Blue fluorescence measured. Compare, (A)-ErSO: ^24hrIC5o = 15 ± 2 nM. Table 2. Breast cancer cell inhibitory activity (^6hTC5o) in other tested compounds.*

>1000 nM >1000 nM > 1000 nM

* n = 3; 6,000 MCF-7 cells/well, 6-hour incubation followed by media aspiration and Alamar

Blue fluorescence measured. ^# ICso based on a single isolated isomer.

Table 3. Toxicity in mice with I.V. dosing.*

* CD-I Female Mice, compounds were formulated in 5% DMSO, 10% Tween-20, 85% PBS and solutions filtered prior to tail-vein injection; 3 mice were treated with each (A)-ErSO dose, 2-3 mice per (S)-ErSO dose level, and 2 mice per (A)-ErSO(OH) dose.

[0082] The results in Table 3 indicates that decreasing clogP and clogBB is a viable strategy to reducetoxicity.

[0083] Mechanism of Action ofErSO(OH): The actions of ErSO(OH) include, but are not limited to, inducing lethal hyperactivation of the endoplasmic reticulum stress sensor, the unfolded protein response (UPR). The endoplasmic reticulum (EnR) stress sensor of the unfolded protein response (UPR) balances the synthesis of new proteins with the availability of chaperones and other proteins that help fold and transport proteins within cells. The anticipatoryUPR pathway is activated in the absence of unfolded proteins and anticipates future needs for new protein folding capacity. [0084] To induce lethal hyperactivation of the unfolded protein response ErSO(OH) binds to ERa in cancer cells. This leads to activation of phospholipase C g (PLCy). Activated PLCy enzymatically produces inositol triphosphate (IP3). The IP3 binds to and opens endoplasmic reticulum IP₃ receptor calcium channels in the EnR. Opening the IP₃R calcium channels resultsin very rapid efflux of calcium stored in the lumen (interior) of the endoplasmic reticulum into the cell body. This hyperactivates the EIPR. When activated, one arm of the UPR, the PERK arm, inhibits protein synthesis. Activation of another arm of the EIPR, IREla, induces formationof the active spliced from of the mRNA encoding the transcription factor XBP-1 (spXBP-1). To restore calcium homeostasis, powerful SERCA pumps in the membrane of the endoplasmic reticulum carry out ATP dependent pumping of calcium from the cell body into the interior of the EnR. Because the IP₃R calcium channels remain open, the calcium pumped into the lumenof the EnR leaks back out. This creates a futile cycle that depletes intracellular ATP.

[0085] UPR markers and inhibitors: Formation of spXBP-1 mRNA is used as a marker for EIPR activation. The widely used small molecule 2-APB locks the HERs closed and prevents the calcium efflux and EIPR hyperactivation. The small molecule thapsigargin (THG) potently inhibits the SERCA pumps and prevents the cell from using up its ATP stores.

General Synthetic Methods

[0086] The invention also relates to methods of making the compounds and compositions of the invention. The compounds and compositions can be prepared by any of the applicable techniques of organic synthesis, for example, the techniques described herein (see Scheme 1). Many such techniques are well known in the art. However, many of the known techniques are elaborated in Compendium of Organic Synthetic Methods (John Wiley & Sons, New York), Vol. 1, Ian T. Harrison and Shuyen Harrison, 1971; Vol. 2, Ian T. Harrison and Shuyen Harrison, 1974; Vol. 3, Louis S. Hegedus and Leroy Wade, 1977; Vol. 4, Leroy G. Wade, Jr., 1980; Vol. 5, Leroy G. Wade, Jr., 1984; and Vol. 6, Michael B. Smith; as well as standard organic reference texts such as March's Advanced Organic Chemistry: Reactions, Mechanisms, and Structure , 5^th Ed. by M.B. Smith and J. March (John Wiley & Sons, New York, 2001), Comprehensive Organic Synthesis; Selectivity, Strategy & Efficiency in Modern Organic Chemistry , in 9 Volumes, Barry M. Trost, Ed. -in-Chief (Pergamon Press, New York, 1993 printing) ); AdvancedOrganic Chemistry, Part B: Reactions and Synthesis, Second Edition, Carey and Sundberg (1983); Protecting Groups in Organic Synthesis,

Second Edition, Greene, T.W., and Wutz, P.G.M., John Wiley & Sons, New York; and Comprehensive Organic Transformations , Larock,R.C., Second Edition, John Wiley & Sons, New York (1999).

[0087] A number of exemplary methods for the preparation of the compounds of the invention are provided below. These methods are intended to illustrate the nature of such preparations arenot intended to limit the scope of applicable methods.

[0088] Generally, the reaction conditions such as temperature, reaction time, solvents, work-up procedures, and the like, will be those common in the art for the particular reaction to be performed. The cited reference material, together with material cited therein, contains detailed descriptions of such conditions. Typically, the temperatures will be -100 °C to 200 °C, solventswill be aprotic or protic depending on the conditions required, and reaction times will be 1 minute to 2 days. Work-up typically consists of quenching any unreacted reagents followed bypartition between a water / organic layer system (extraction) and separation of the layer containing the product.

[0089] Oxidation and reduction reactions are typically carried out at temperatures near room temperature (about 20 °C), although for metal hydride reductions frequently the temperature is reduced to 0 °C to -100 °C. Heating can also be used when appropriate. Solvents are typically aprotic for reductions and may be either protic or aprotic for oxidations. Reaction times are adjusted to achieve desired conversions.

[0090] Condensation reactions are typically carried out at temperatures near room temperature, although for non-equilibrating, kinetically controlled condensations reduced temperatures (0 °C to - 100 °C) are also common. Solvents can be either protic (common in equilibrating reactions)or aprotic (common in kinetically controlled reactions). Standard synthetic techniques such as azeotropic removal of reaction by-products and use of anhydrous reaction conditions (e.g. inert gas environments) are common in the art and will be applied when applicable.

[0091] Protecting Groups. The term "protecting group" refers to any group which, when bound to a hydroxy or other heteroatom prevents undesired reactions from occurring at this group and which can be removed by conventional chemical or enzymatic steps to reestablish the hydroxyl group. The particular removable protecting group employed is not always critical and preferred removable hydroxyl blocking groups include conventional substituents such as, for example, allyl, benzyl, acetyl, chloroacetyl, thiobenzyl, benzylidene, phenacyl, methyl methoxy, silyl ethers (e.g., trimethyl silyl (TMS), /-butyl -di phenyl si lyl (TBDPS), or /-butyldimethylsilyl (TBS))and any other group that can be introduced chemically onto a hydroxyl functionality and later selectively removed either by chemical or enzymatic methods in mild conditions compatible withthe nature of the product.

[0092] Suitable hydroxyl protecting groups are known to those skilled in the art and disclosed in more detail in T.W. Greene, Protecting Groups In Organic Synthesis ; Wiley: New York, 1981 ("Greene") and the references cited therein, and Kocienski, Philip J.; Protecting Groups (Georg Thieme Verlag Stuttgart, New York, 1994), both of which are incorporated herein by reference.

[0093] Protecting groups are available, commonly known and used, and are optionally used to prevent side reactions with the protected group during synthetic procedures, i.e. routes or methods to prepare the compounds by the methods of the invention. For the most part the decision as to which groups to protect, when to do so, and the nature of the chemical protecting group ("PG" or "P") will be dependent upon the chemistry of the reaction to be protected against(e.g., acidic, basic, oxidative, reductive or other conditions) and the intended direction of the synthesis.

Scheme 1. General synthetic route.

[0094] Synthesis of other compounds described herein were carried out in a similar manner by selection of appropriate starting materials. Additional data and synthetic details for preparation of similar compounds are provided in International Publication No. WO 2020/009958 (Shapiro et al.) and U.S. Patent Application No. 16/801,839 (Shapiro et al.), which applications are incorporated herein by reference. Basis of Assays for Killing of Cancer Cells.

[0095] ALAMAR BLUE/RAP TIN AL ASSAY. Live cells maintain a reducing environment. The non-fluorescent cell permeable ingredient of Alamar Blue® (resazurin) is taken up by cells. In living cells, it is reduced to the fluorescent compound resorufm. Using a standard curve of cell number versus fluorescence the number of live cells in a test sample can be determined; and the measured fluorescence (Axcit. = 555 nm, Amission. = 585 nm) is directly proportional to the number of viable cells in a test sample. At highconcentrations raptinal (IOOmM) kills 100% of cells. The vehicle in which the test compound is dissolved is not toxic (1% DMSO). Thus, after subtracting the blank from medium + 100% dead cells alone, the fluorescence reading for vehicle corresponds to 100% viable cells and the signal for raptinal corresponds to 0% viable cells. 6000 cells were seeded per well in a 96-well plate and allowed to adhere overnight before DMSO solutions of compounds were added to each well. Final concentration of DMSO in each well is 1%, final volume: 100 pL. At the end of 6 or 24 hours, media was aspirated and new media (100 pL) was added. Alamar blue solution was added (10 pL of 1 mg resazurin per 10 mL PBS). After 2-4 hours incubation, fluorescence (Axcit. = 555 nm, Amission. = 585 nm) was measured. The fluorescence of each well was read with a SpectraMax M3 plate reader (Molecular Devices). Percent dead cells was determined by comparison to a 100% dead cells control (100 pM raptinal treated cells). ICso was calculated using Origin Pro V10. While this assay provides a less direct measurement of cell death than the trypan blue assay, it is more easily scaled up to large numbers of samples.

Cell lines used for the therapeutic target: ERq positive breast cancer cells [0096] MCF-7 (Michigan Cancer Foundation-7) . ERa positive, the most widely used ERa positive breast cancer cell line. Estrogen greatly stimulates their growth; sensitive to z-OHT andfulvestrant/ICI.

Pharmaceutical Formulations

[0097] The compounds described herein can be used to prepare therapeutic pharmaceutical compositions, for example, by combining the compounds with a pharmaceutically acceptable diluent, excipient, or carrier. The compounds may be added to a carrier in the form of a salt or solvate. For example, in cases where compounds are sufficiently basic or acidic to form stable nontoxic acid or base salts, administration of the compounds as salts may be appropriate. Examples of pharmaceutically acceptable salts are organic acid addition salts formed with acids that form a physiologically acceptable anion, for example, tosylate, methanesulfonate, acetate, citrate, malonate, tartrate, succinate, benzoate, ascorbate, a-ketoglutarate, and b- glycerophosphate.

Suitable inorganic salts may also be formed, including hydrochloride, halide, sulfate, nitrate, bicarbonate, and carbonate salts.

[0098] Pharmaceutically acceptable salts may be obtained using standard procedures well knownin the art, for example by reacting a sufficiently basic compound such as an amine with a suitableacid to provide a physiologically acceptable ionic compound. Alkali metal (for example, sodium, potassium or lithium) or alkaline earth metal (for example, calcium) salts of carboxylic acids can also be prepared by analogous methods.

[0099] The compounds of the formulas described herein can be formulated as pharmaceutical compositions and administered to a mammalian host, such as a human patient, in a variety of forms. The forms can be specifically adapted to a chosen route of administration, e.g., oral orparenteral administration, by intravenous, intramuscular, topical or subcutaneous routes.

[0100] The compounds described herein may be systemically administered in combination with a pharmaceutically acceptable vehicle, such as an inert diluent or an assimilable edible carrier. For oral administration, compounds can be enclosed in hard or soft-shell gelatin capsules, compressed into tablets, or incorporated directly into the food of a patient's diet. Compounds may also be combined with one or more excipients and used in the form of ingestible tablets, buccal tablets, troches, capsules, elixirs, suspensions, syrups, wafers, and the like. Such compositions and preparations typically contain at least 0.1% of active compound. The percentage of the compositions and preparations can vary and may conveniently be from about 0.5% to about 60%, about 1% to about 25%, or about 2% to about 10%, of the weight of a givenunit dosage form. The amount of active compound in such therapeutically useful compositions can be such that an effective dosage level can be obtained.

[0101] The tablets, troches, pills, capsules, and the like may also contain one or more of the following: binders such as gum tragacanth, acacia, corn starch or gelatin; excipients such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid andthe like; and a lubricant such as magnesium stearate. A sweetening agent such as sucrose, fructose, lactose or aspartame; or a flavoring agent such as peppermint, oil of wintergreen, or cherry flavoring, may be added. When the unit dosage form is a capsule, it may contain, in addition to materials of the above type, a liquid carrier, such as a vegetable oil or a poly ethyleneglycol. Various other materials may be present as coatings or to otherwise modify the physical form of the solid unit dosage form. For instance, tablets, pills, or capsules may be coated with gelatin, wax, shellac or sugar and the like. A syrup or elixir may contain the active compound, sucrose or fructose as a sweetening agent, methyl and propyl parabens as preservatives, a dye and flavoring such as cherry or orange flavor. Any material used in preparing any unit dosage form should be pharmaceutically acceptable and substantially non-toxic in the amounts employed. In addition, the active compound may be incorporated into sustained-releasepreparations and devices.

[0102] The active compound may be administered intravenously or intraperitoneally by infusion or injection. Solutions of the active compound or its salts can be prepared in water, optionally mixed with a nontoxic surfactant. Dispersions can be prepared in glycerol, liquid polyethylene glycols, triacetin, or mixtures thereof, or in a pharmaceutically acceptable oil. Under ordinary conditions of storage and use, preparations may contain a preservative to prevent the growth of microorganisms.

[0103] Pharmaceutical dosage forms suitable for injection or infusion can include sterile aqueoussolutions, dispersions, or sterile powders comprising the active ingredient adapted for the extemporaneous preparation of sterile injectable or infusible solutions or dispersions, optionally encapsulated in liposomes. The ultimate dosage form should be sterile, fluid and stable under the conditions of manufacture and storage. The liquid carrier or vehicle can be a solvent or liquid dispersion medium comprising, for example, water, ethanol, a polyol (for example, glycerol, propylene glycol, liquid polyethylene glycols, and the like), vegetable oils, nontoxic glyceryl esters, and suitable mixtures thereof. The proper fluidity can be maintained, for example, by the formation of liposomes, by the maintenance of the required particle size in the case of dispersions, or by the use of surfactants. The prevention of the action of microorganisms can be brought about by various antibacterial and/or antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, thimerosal, and the like. In many cases, it will be preferableto include isotonic agents, for example, sugars, buffers, or sodium chloride. Prolonged absorption of the injectable compositions can be brought about by agents delaying absorption, for example, aluminum monostearate and/or gelatin. [0104] Sterile injectable solutions can be prepared by incorporating the active compound in the required amount in the appropriate solvent with various other ingredients enumerated above, as required, optionally followed by filter sterilization. In the case of sterile powders for the preparation of sterile injectable solutions, methods of preparation can include vacuum drying and freeze-drying techniques, which yield a powder of the active ingredient plus any additional desired ingredient present in the solution.

[0105] For topical administration, compounds may be applied in pure form, e.g., when they are liquids. However, it will generally be desirable to administer the active agent to the skin as a composition or formulation, for example, in combination with a dermatologically acceptable carrier, which may be a solid, a liquid, a gel, or the like.

[0106] Useful solid carriers include finely divided solids such as talc, clay, microcrystalline cellulose, silica, alumina, and the like. Useful liquid carriers include water, dimethyl sulfoxide (DMSO), alcohols, glycols, or water-alcohol/glycol blends, in which a compound can be dissolved or dispersed at effective levels, optionally with the aid of non-toxic surfactants. Adjuvants such as fragrances and additional antimicrobial agents can be added to optimize the properties for a given use. The resultant liquid compositions can be applied from absorbent pads, used to impregnate bandages and other dressings, or sprayed onto the affected area using a pump-type or aerosol sprayer.

[0107] Thickeners such as synthetic polymers, fatty acids, fatty acid salts and esters, fatty alcohols, modified celluloses, or modified mineral materials can also be employed with liquid carriers to form spreadable pastes, gels, ointments, soaps, and the like, for application directly tothe skin of the user.

[0108] Examples of dermatological compositions for delivering active agents to the skin are known to the art; for example, see U.S. Patent Nos. 4,992,478 (Geria), 4,820,508 (Wortzman), 4,608,392 (Jacquet et ah), and 4,559,157 (Smith et ah). Such dermatological compositions canbe used in combinations with the compounds described herein where an ingredient of such compositions can optionally be replaced by a compound described herein, or a compound described herein can be added to the composition. [0109] Useful dosages of the compounds described herein can be determined by comparing thei rin vitro activity, and in vivo activity in animal models. Methods for the extrapolation of effectivedosages in mice, and other animals, to humans are known to the art; for example, see U.S. PatentNo. 4,938,949 (Borch et al.). The amount of a compound, or an active salt or derivative thereof, required for use in treatment will vary not only with the particular compound or salt selected butalso with the route of administration, the nature of the condition being treated, and the age and condition of the patient, and will be ultimately at the discretion of an attendant physician or clinician.

[0110] In general, however, a suitable dose will be in the range of from about 0.5 to about 100 mg/kg, e.g., from about 10 to about 75 mg/kg of body weight per day, such as 3 to about 50 mgper kilogram body weight of the recipient per day, preferably in the range of 6 to 90 mg/kg/day,most preferably in the range of 15 to 60 mg/kg/day.

[0111] The compound is conveniently formulated in unit dosage form; for example, containing 5to 1000 mg, conveniently 10 to 750 mg, most conveniently, 50 to 500 mg of active ingredient per unit dosage form. In one embodiment, the invention provides a composition comprising a compound of the invention formulated in such a unit dosage form.

[0112] The compound can be conveniently administered in a unit dosage form, for example, containing 5 to 1000 mg/m², conveniently 10 to 750 mg/m², most conveniently, 50 to 500 mg/m²of active ingredient per unit dosage form. The desired dose may conveniently be presented in a single dose or as divided doses administered at appropriate intervals, for example, as two, three, four or more sub-doses per day. The sub-dose itself may be further divided, e.g., into a number of discrete loosely spaced administrations.

[0113] The desired dose may conveniently be presented in a single dose or as divided doses administered at appropriate intervals, for example, as two, three, four or more sub-doses per day. The sub-dose itself may be further divided, e.g., into a number of discrete loosely spaced administrations; such as multiple inhalations from an insufflator or by application of a plurality of drops into the eye.

[0114] The compounds described herein can be effective anti -tumor agents and have higher potency and/or reduced toxicity as compared to BHPI. Preferably, compounds of the inventionare more potent and less toxic than BHPI, and/or avoid a potential site of catabolic metabolism encountered with BHPI, i.e., have a different metabolic profile than BHPI. Furthermore, the compounds described herein cause less severe ataxia than BHPI and other known compounds.

[0115] The invention provides therapeutic methods of treating cancer in a vertebrate such as a mammal, which involve administering to a mammal having cancer an effective amount of a compound or composition described herein. A mammal includes a primate, human, rodent, canine, feline, bovine, ovine, equine, swine, caprine, bovine and the like. Cancer refers to any of the various type of malignant neoplasm, which are in general characterized by an undesirable cellular proliferation, e.g., unregulated growth, lack of differentiation, local tissue invasion, andmetastasis. Cancers that can be treated by a compound described herein include, for example, breast cancer, cervical carcinoma, colon cancer, endometrial cancer, leukemia, lung cancer, melanoma, pancreatic cancer, prostate cancer, ovarian cancer, or uterine cancer, and in particular, any cancer that is ERa positive.

[0116] The ability of a compound of the invention to treat cancer may be determined by using assays well known to the art. For example, the design of treatment protocols, toxicity evaluation, data analysis, quantification of tumor cell kills, and the biological significance of the use of transplantable tumor screens are known. In addition, ability of a compound to treat cancer maybe determined using the Tests as described below.

[0117] The following Examples are intended to illustrate the above invention and should not be construed as to narrow its scope. One skilled in the art will readily recognize that the Examples suggest many other ways in which the invention could be practiced. It should be understood that numerous variations and modifications may be made while remaining within the scope of the invention.

EXAMPLES

Example 1. Synthetic procedures.

[0118] General Information'. Unless otherwise stated, reagents were purchased from commercial sources and used without further drying or purification. Solvents used herein were dried after being passed through activated alumina columns. All reactions were run in flame- dried glassware under a positive pressure of nitrogen gas. ¾ NMR and ¹³C NMR experiments were conducted on a Bruker cryoprobe at 500 MHz and 188 MHz respectively. Spectra obtainedin CD3OD were referenced for 3.31 ppm and 49.00 ppm for 'H and ¹³C NMR spectra, respectively. NMR multiplicities are reported as: s = singlet, d = doublet, t = triplet, q = quartet, m = multiplet. ¹³C multiplicities are all singlets unless otherwise noted.

(R/S)- ErSO(OH) (S)-ErSO(OH) (R)-ErSO(OH)

[0119] Synthesis of (/?)- and (A)-ErSO(OH): A round bottom flask was charged with 1- bromo-4-(trifluoromethoxy)benzene (3.08 mmol) and dissolved in THF (3.0 mL). The reaction mixture was cooled to -78 °C and a solution of n-BuLi (2.77 mmol, 1.7 mL) added dropwise over 10 minutes. The reaction was stirred for 1 hour. In another flask, the desired isatin (1.54 mmol) was added and dissolved in THF (9.4 mL). This solution of isatin was added to the reaction vessel dropwise over 10 minutes. The resultant mixture was stirred at -78 °C for 1 hour, warmed to r.t.,and then stirred for 1 hour. The reaction was quenched with water (10 mL). The solution was extracted with ethyl acetate (3x) and the combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. A new round bottom flask was charged with crude tertiary alcohol and catechol (6.95 mmol) and dissolved in dichloromethane (7.7 mL). The reaction mixture was then placed in an ice bath and triflic acid (TfOH, 0.7 mL) was then added dropwise. The reaction vessel was removed from the ice bath and stirred at room temperature fori hour. The reaction mixture was then poured into an ice-filled sodium bicarbonate and the aqueous solution was extracted with ethyl acetate (3x). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. The resultant oil was then purified via column chromatography and chiral separation.

[0120] Chiral Separation of (R)- and (S)-ErSO(OH): (R,S) ErSO(OH) was separated into its respective enantiomers using preparative chiral HPLC separation (Lux® 5 μm Cellulose-1, 250 x 21.2 mm, AXIA^™ Packed, isocratic: 40% i-PrOH/Hexanes. Stereochemistry inferred from WO 2020/009958. This chiral separation yields: (S)-ErSO(OH) – First peak on HPLC, as an amorphous white solid after lyophilization from neat acetonitrile.¹H NMR: (CD3OD, 500 MHz) į: 7.56 (d, J = 7.8 Hz, 1H), 7.48 (d, J = 7.6 Hz, 1H), 7.37 (d, J = 8.9 Hz, 2H), 7.27 (d, J = 9.2 Hz, 2H), 7.24 (t, J = 7.9 Hz, 1H), 6.74 (d, J = 8.3 Hz, 1H), 6.69 (d, J = 2.3 Hz, 1H), 6.52 (dd, J = 8.4, 2.4 Hz, 1H).¹⁹FNMR: (CD3OD, 471 MHz) į: -59.49, -62.98. HRMS (ESI): m/z calc. for C22H13NO4F6 [M+H]+ 470.827, found: 470.0829. (R)-ErSO(OH) – Second peak on HPLC, as an amorphous white solid after lyophilization from neat acetonitrile.

(R/S)-ErSO(OH) [0121] 3-(3,4-dihydroxyphenyl)-3-(4-(trifluoromethoxy)phenyl)-7-(trifluoromethyl)indolin- 2-one, (R/S)-ErSO(OH): ¹H NMR (CD3OD, 500 MHz) į: 7.53 (d, J = 7.8 Hz, 1H), 7.44 (d, J = 7.3 Hz, 1H), 7.34 (d, J = 8.9 Hz, 2H), 7.26 – 7.18 (m, 5H), 6.71 (d, J = 8.3 Hz, 1H), 6.67 (d, J = 2.3 Hz, 1H), 6.49 (dd, J = 8.3, 2.3 Hz, 1H).¹³C NMR (CD3OD, 126 MHz) į: 181.34,149.79 (q, J = 1.8 Hz), 146.54, 146.31, 142.05, 139.84 (q, J = 1.9 Hz), 136.99, 133.33, 131.29, 131.06, 126.07 (q, J = 4.5 Hz), 125.16 (q, 7= 271.1 Hz), 123.49, 121.97, 121.89 (q, J = 256.5 Hz), 120.66, 116.67, 116.25, 113.72 (q, J = 33.38 Hz), 62.29. ¹⁹F NMR (CDrOD, 471 MHz) d: -59.49, -62.98.

[0122] Intermediates for compounds having a substituted oxindole-core can be prepared fromthe corresponding starting material for the compound, for example, as follows.

[0123] 6-chloro-3-hydroxy-7-methyl-3-(4-(trifluoromethoxy)phenyl)indolin-2-one (7): A reaction vessel was charged with substituted aniline (2.82 mmol), 1M HC1 (2.82 mL), water (18.8 mL), anhydrous sodium sulfate (16.92 mmol), and hydroxylamine hydrochloride (9.17 mmol). The mixture was heated to boiling and then chloral hydrate was added as one portion. The reaction was kept at reflux for 40 minutes, then cooled to reflux and the aqueous solutionwas extracted with ethyl acetate (3x). The combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Concentrated sulfuric acid (3 mL) was then added to the resultant residue. This solution was heated to 80 °C for 20 minutes, then poured onto ice. Theresulting aqueous mixture was extracted with ethyl acetate (3x), and the combined organic layersdried over sodium sulfate, filtered, and concentrated in vacuo. The red-brown solid obtained afterconcentration proved to be poorly soluble in most organic solvents.

[0124] To a new reaction vessel, the desired phenyl bromide (3.08 mmol) and dissolved in THF (3.0 mL). The reaction mixture was cooled to -78 °C and a solution of n-BuLi (2.77 mmol, 1.73mL) added dropwise over 10 minutes. The reaction was stirred for 1 hour. In another flask, 6- chloro-7- methylisatin (1.54 mmol) was added and dissolved in THF (9.4 mL). This solution of isatin was added to the reaction vessel dropwise over 10 minutes. The resultant mixture was stirred at -78 °C for 1 hour, warmed to r.t, and then stirred for 1 hour. The reaction was quenched with water (10 mL). The solution was extracted with ethyl acetate (3x) and the combined organic layers were dried over sodium sulfate, filtered, and concentrated in vacuo. Theresulting oil was run through a silica plug (elution solvent gradient: 10% EtO Ac/Hexanes ramped to 100% EtOAc). [0125] 7 was isolated in 24% yield over three synthetic steps. ¾ NMR (CD3OD, 500 MHz) d:

7.46 (d, J = 8.85 Hz 2H), 7.23 (d, J = 7.98 Hz, 2H), 7.10 (d, J = 7.97 Hz 1H), 6.98 (d, J = 8.02 Hz, 1H), 2.35 (s, 3H). ¹³C NMR (CD3OD, 188 MHz) d: 181.25, 150.17 (q, J = 1.83 Hz), 143.14, 140.98, 136.68, 132.74, 128.63, 124.53, 124.40, 121.88 (q, J = 255.75 Hz), 121.86, 119.76, 78.91, 14.11. HRMS (ESI): m/z calc, for CieHiiNCbFsClNa [M+Na]⁺ 380.0277, found 380.0284.

Example 2. Pharmaceutical Dosage Forms.

[0126] The following formulations illustrate representative pharmaceutical dosage forms that may be used for the therapeutic or prophylactic administration of a compound of a formula described herein, a compound specifically disclosed herein, or a pharmaceutically acceptable saltor solvate thereof (hereinafter referred to as 'Compound X'):

(i) Tablet 1 mg/tablet

'Compound X' 100.0

Lactose 77.5

Povidone 15.0

Croscarmellose sodium 12.0

Microcrystalline cellulose 92.5

Magnesium stearate 3,0

300.0

(ri) Tablet 2 mg/tablet

'Compound X' 20.0

Microcrystalline cellulose 410.0

Starch 50.0

Sodium starch glycolate 15.0

Magnesium stearate 5,0

500.0

(rii) Capsule mg/capsule

'Compound X' 10.0

Colloidal silicon dioxide 1.5

Lactose 465.5

Pregelatinized starch 120.0

Magnesium stearate 3,0

600.0 Injection 1 (1 mg/mL) mg/mL

'Compound X' (free acid form) 1.0 Dibasic sodium phosphate 12.0

Monobasic sodium phosphate 0.7

Sodium chloride 4.5

1.0 N Sodium hydroxide solution q.s.

(pH adjustment to 7.0-7.5)

Water for injection q.s. ad 1 mL

(V) Injection 2 (10 mg/mL) mg/mL

'Compound X' (free acid form) 10.0

Monobasic sodium phosphate 0.3

Dibasic sodium phosphate 1.1

Polyethylene glycol 400 200.0

0.1 N Sodium hydroxide solution q.s.

(pH adjustment to 7.0-7.5)

Water for injection q.s. ad 1 mL

(Vi) Aerosol mg/can

'Compound X' 20

Oleic acid 10

Trichloromonofluoromethane 5,000

Diehl orodifluoromethane 10,000

Dichlorotetrafluoroethane 5,000

(vii) Topical Gel 1 wt.%

'Compound X' 5%

Carbomer 934 1.25%

Triethanolamine q.s.

(pH adjustment to 5-7)

Methyl paraben 0.2%

Purified water q.s. to lOOg

(viii) Topical Gel 2 wt.%

'Compound X' 5%

Methylcellulose 2%

Methyl paraben 0.2%

Propyl paraben 0.02%

Purified water q.s. to lOOg

(ix) Topical Ointment wt.%

'Compound X' 5%

Propylene glycol 1%

Anhydrous ointment base 40%

Polysorbate 80 2%

Methyl paraben 0.2%

Purified water q.s. to lOOg (x) Topical Cream 1 wt.%

'Compound X' 5% White bees wax 10% Liquid paraffin 30% Benzyl alcohol 5% Purified water q.s. to lOOg Topical Cream 2 wt.%

'Compound X' 5%

Stearic acid 10% Glyceryl monostearate 3% Polyoxyethylene stearyl ether 3% Sorbitol 5%

Isopropyl palmitate 2 % Methyl Paraben 0.2% Purified water q.s. to lOOg

[0127] These formulations may be prepared by conventional procedures well known in the pharmaceutical art. It will be appreciated that the above pharmaceutical compositions may be varied according to well-known pharmaceutical techniques to accommodate differing amountsand types of active ingredient 'Compound X'. Aerosol formulation (vi) may be used in conjunction with a standard, metered dose aerosol dispenser. Additionally, the specific ingredients and proportions are for illustrative purposes. Ingredients may be exchanged for suitable equivalents and proportions may be varied, according to the desired properties of the dosage form of interest.

[0128] While specific embodiments have been described above with reference to the disclosed embodiments and examples, such embodiments are only illustrative and do not limit the scope ofthe invention. Changes and modifications can be made in accordance with ordinary skill in the art without departing from the invention in its broader aspects as defined in the following claims.

[0129] All publications, patents, and patent documents are incorporated by reference herein, as though individually incorporated by reference. No limitations inconsistent with this disclosureare to be understood therefrom. The invention has been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope ofthe invention.

Claims

CLAIMS What is claimed is:

1. A compound of Formula (I):

or a salt thereof, wherein:

X is O, S, or NR^d;

Z is O, S, or NR^d;

R¹ is trifluoromethyl, alkyl, cycloalkyl, heterocyclyl, aryl, heteroaryl, halo,

-OR^a, -SR^A,or -N(R^a)₂;

R², R³ and R⁴ are each independently H, halo, -OR^A, -SR^A, -N(R^A)₂, alkyl, cycloalkyl, heterocyclyl, aryl, or heteroaryl;

A¹, A², and A³ are each independently H, OH, halo, or alkyl;

G¹ is -OR^b, -SR^b, -S(=0)₂R^b, alkyl, or halo;

G² is -OR^c, -SR^C, -S(=0)₂R^c, alkyl, or halo;

G³ is -OR^w, -SR^W, or -S(=0)₂R^w halo;

R^a, R^b, R^c, R^d, and R^w are each independently trifluoromethyl, H, or alkyl; wherein each alkyl, cycloalkyl, heterocyclyl, aryl, and heteroaryl is optionally substituted with one or more substituents.

2. The compound of claim 1, or a salt thereof, wherein X is NH.

3. The compound of claim 1 or claim 2, or a salt thereof, wherein Z is O.

4. The compound of any one of claims 1-3, or a salt thereof, wherein R¹ is CF3 or Me.

5. The compound of any one of claims 1-4, or a salt thereof, wherein R² is H or halo, and R³ and R⁴ are both H.

6. The compound of any one of claims 1-5, or a salt thereof, wherein A¹, A², and

A³ are each H.

7. The compound of any one of claims 1-6, or a salt thereof, wherein G² is OCF₃.

8. The compound of any one of claims 1-7, or a salt thereof, wherein G¹ and G³ are OH.

9. The compound of any one of claims 1-8, or a salt thereof, wherein the compound is levorotatory.

10. The compound of any one of claims 1-8, or a salt thereof, wherein the compound is dextrorotatory.

11. The compound of claim 1, or a salt thereof, wherein the compound is a compound of Formula (II), or a salt thereof, or Formula (III), or a salt thereof:

12. The compound of claim 1, or a salt thereof, wherein the compound is a compound of

Formula (IV):

or a salt thereof, wherein G² is -OR^c, and R^c and R¹ are each independently trifluoromethyl, alkyl, or cycloalkyl.

13. The compound of claim 1, or a salt thereof, wherein the compound is ( R )- or (S)- (F), (G), (H), (K), (J), or (X), or a salt of any of the foregoing:

14. The compound of any one of claims 1-13, or a salt thereof, wherein the compound has a binding affinity for the alpha estrogen receptor (ERa), and the IC50 of the binding affinity is less than about 200 nM.

15. A compound of F ormul a (V) :

or a salt thereof, wherein:

R¹ is Me, Et, CF₃, or CH2CF3;

R² is H, Me, Et, CF₃, CH₂CF₃, F, Cl, or OH;

G¹ is F, Me, CF₃, OCF₃, OH, or OP;

G² is F, Me, CF₃, OCF₃, OH, or OP; and G³ is F, Me, CF₃, OCF₃, OH, or OP; wherein P, when present, is an oxygen protecting group.

16. The compound of claim 15, or a salt thereof, wherein the compound is the (//(-enantiomer.

17. The compound of claim 15, or a salt thereof, wherein the compound is the (^-enantiomer.

18. The compound of claim 15, or a salt thereof, wherein the compound is:

19. A pharmaceutical composition, comprising the compound of any one of claims 1-18, or a salt thereof, and at least one pharmaceutically acceptable carrier.

20. A method of treating an ERa positive cancer, comprising administering to a mammal having an ERa positive cancer a therapeutically effective amount of a compound of any one of claims 1-18, or a salt thereof, thereby treating the ERa positive cancer.

21. The method of claim 20, wherein the mammal is a human.

22. The method of claim 20, wherein the ERa positive cancer is breast cancer, ovarian cancer, uterine cancer, cervical carcinoma, or endometrial cancer.

23. The method of any one of claims 20-22, wherein the compound is:

or a salt thereof.

24. A use of the compound of any one of claims 1-18, or a salt thereof, for the treatment of an ERa positive cancer in a mammal in need thereof, wherein a therapeutically effective amount of the compound, or a salt thereof, is administered to the mammal, thereby treating the ERa positive cancer.

25. The use of claim 24, wherein the mammal is a human.

26. The use of claim 24, wherein the ERa positive cancer is breast cancer, ovarian cancer, uterine cancer, cervical carcinoma, or endometrial cancer.

27. The use of any one of claims 24-26, wherein the compound is:

or a salt thereof.