WO2007129005A1 - Aminoacid derivatives of thiazoles as inhibitors of pi3 kinase - Google Patents

Abstract

Compounds of formula (I) are inhibitors of PI3 kinase activity, and useful in treatment of, inter alia, autoimmune, inflammatory and proliferative diseases; wherein s is 0 or 1; U is hydrogen or halogen; X is -(C=O)-, or an optionally substituted divalent phenylene, pyridinylene, pyrimidinylene, or pyrazinylene radical, or a bond; P is optionally substituted C1-C6 alkyl and Z is -(CH2)Z-Y1-L1-R or Z is optionally substituted C1-C6 alkyl and P is -(CH2)Z-Y1-L1-R; and z, Y1, L1 and R are as defined in the claims.

Description

AMINOACID DERIVATIVES OF THIAZOLES AS INHIBITORS OF PI3 KINASE

This invention relates to a series of amino acid esters, to compositions containing them, to processes for their preparation and to their use in medicine as PI3 kinase inhibitors for the treatment of autoimmune and inflammatory diseases, including rheumatoid arthritis, psoriasis, inflammatory bowel disease, Crohns disease, ulcerative colitis, chronic obstructive pulmonary disease, asthma, multiple sclerosis, diabetes, atopic dermatitis, graft versus host disease, systemic lupus erythematosus and others. The invention also relates to the use of such compounds in the treatment of proliferative disorders such as cancer, prostate hyperplasia, fibrosis and diabetic retinopathy.

Background to the Invention

The phosphoinositide 3-kinase (PI3 Kinase) pathway plays a central role in regulating many biological events through phosphorylation of the plasma membrane lipid phosphatidylinositol 3,4-biphosphate (Ptdlns(4,5)P₂), to produce the key second messenger phosphatidyl 3,4,5-triphosphate PtdIns(3,4,5)P₃, [Krystal G., Semin. Immunol., 2000, 12, 397-403]. Such phoshorylation of Ptdlns(4,5)P₂ at the D-3 position of the inositol ring in response to cell stimulation by growth factors and hormones sets in motion a coordinated set of events leading to cell proliferation, cell growth, cell cycle entry, cell migration, membrane trafficking, glucose transport, superoxide production and cell survival. PI3 Kinases can be classified into three subfamilies according to structure and substrate specificity [Vanhaesebroeck et al., Annu. Rev. Biochem., 2001 , 70, 535-602]. The best characterised of these subfamilies are class I PI3 kinases consisting of two subgroups. Class IA and Class IB enzymes signal downstream of receptor tyrosine kinases and heterotrimeric G- protein-coupled receptors respectively. Class IA PI3 kinases consist of a p85 regulatory subunit and a p110 catalytic subunit [Cantley, Science, 2002, 296, 1655- 1657]. There are three catalytic isoforms (p110α, p110β and p110δ) and five regulatory isoforms (p85α, p85β and p55γ, which are encoded by specific genes, and p55α and p50α that are produced by alternate splicing of the p85α gene), [Ward and Finan, Current Opinion in Pharmacology, 2003, 3, 426]. The regulatory subunit maintains the p110 catalytic subunit in a low-activity state in quiescent cells and mediates its activation by the interaction of the SH2 domain and phoshotyrosine residues of other proteins. In addition, p85 binds and integrates signals from intracellular proteins such as protein kinase C (PKC), SHP1 , Rac, Rho and mutated Ras providing an integration point for activation of p110 and downstream molecules. The only Class IB PI3 Kinase identified to date is the p110γ catalytic subunit, complexed with a p101 regulatory protein. All class I PI3 kinases possess intrinsic protein kinase activity with p110 autophosphorylation and phosphorylation of p85 downregulating the activity of the complex.

Class Il PI3 Kinases are monomeric proteins which lack regulatory subunits and utilise phosphatidylinositol (Ptdlns) and phosphatidylinositol 4-monophosphate (Ptdlns(4)P) as substrates, [Oudit et al, J.Mol.Cell.Cardiol. 2004, 37, 449]. Three mammalian class Il isoforms have been identified PI3K-C2α, PI3K-C2β and PI3K- C2γ.

Class III PI3 kinases are heterodimeric species consisting of adaptor p150 and catalytic (Vps34, 100KDa) subunits.

Signalling proteins with pleckstrin homology domains (PH) domains accumulate at sites of Class 1 PI3 Kinase activation by directly binding to Ptdlns(3,4,5)P₃. PH domains are globular protein domains of about 100 amino acids and are found in a diverse array of proteins including kinases (Akt, PDK1 , Btk), nucleotide exchange factors (eg Vav, GRP1 , ARNO, Sos1 ), GTP-ase activating factors (eg GAP1^m, centaurins), phospholipases (eg PLCγ2). Of particular significance is the serine/threonine kinase Akt, one of the major direct downstream targets of Class 1 PI3 kinases. The PI3 kinase mediated production of Ptdlns(3,4,5)P₃ in response to extracellular stimulation, leads to recruitment of Akt from the cytoplasm to the cell membrane through binding of it's PH domain to the membrane bound Ptdlns(3,4,5)P₃. Such binding induces conformational changes in Akt facilitating phosphorylation at Thr 308 by PDK1 leading to it's activation. Akt modulates cell survival by both up regulating pro-survival pathways (e.g. CREB) and down regulating pro-apoptotic pathways (including BAD, procaspase-9 and Forkhead (FHKR) transcription factors). This Ptdlns(3,4,5)P₃ signalling is negatively regulated by the lipid phosphatase PTEN (phosphatase and tensin homologue deleted on chromosome ten) which converts Ptdlns(3,4,5)P₃to Ptdlns(4,5)P₂.

Mutations in the PI3 kinase pathway in cancer are common and have a role in neoplastic transformation. Amplification or mutation of the gene encoding p110a (PIK3CA) commonly occur in bowel cancer, ovarian cancer, head and neck and cervical squamous cancers, gastric and lung cancers, anaplastic oligodendrogliomas, glioblastoma multiforme and medulloblastomas. Somatic missense mutations of PIK3CA are frequent in HER2-amplified and hormone receptor positive breast cancers. Akt and PTEN are also targets of frequent genomic and epigenetic changes in human cancer. The PI3 kinase-Akt pathway is also required for the oncogenic effects of EGFR.

Leukocyte chemotaxis toward sites of inflammation is primarily mediated by cytokine signalling. It has been shown that regulation of p110γ is mediated via the p101 adapter, engaged by Gp_γ subunits released by activation of GPCRs [Stephens et al, Cell 1997, 89, 105-114]. Class IB PI3 kinase deficient mice, PI3KY^''^", showed in vitro and in vivo impaired migration of neutrophils and macrophages towards chemoattractants [Hirsch et al, Science 2000, 287, 1049-1053 and Li et al, Science 2000, 287, 1046-1049]. p 11 Qγ deficient neutrophils are unable to produce Ptdlns(3,4,5)P₃when stimulated with GPCR agonists such as f MLP, C5a or IL-8. It has been reported [Weiss-Haljiti J. Biol. Chem 2004, 279, 43273-43284] that in macrophages, the chemokine RANTES activates the small GTPase Rac and its target PAK2. This response depends on Gi activation and primarily on the subsequent activation of PI3 kinase γ and Rac. Rac constitutes a subfamily of the Rho family of monomeric GTPases and cycle between active GTP-bound (Rac^GTP) and inactive GDP-bound (Rac^GDP) states. Rho GTPases integrate signals from cellular receptors and membrane components to regulate the cytoskeleton dynamics required for cell locomotion during chemotaxis, phagocytosis and many other cellular responses. A loss of this PI3 kinase γ response could impair the ability of lymphocytes to make cellular contact with antigen presenting cells, thus impeding cell survival and the ability of cells to respond to immune stimulation [Costello et al, Nature Immunol 2002, 3, 1082].

The present invention relates to compounds which are inhibitors of PI3 Kinase activity, particularly PI3 kinase α, and PI3 kinase γ. The compounds are thus of use in medicine, since PI3 Kinases are now and accepted target for therapeutic intervention in, for example, the treatment and prophylaxis of neoplastic, immune and inflammatory disorders. The compounds of the invention are characterised by the presence in the molecule of an amino acid motif, or an amino acid ester motif which is hydrolysable by one or more intracellular carboxylesterases. Compounds of the invention having the amino acid ester motif, which is intrinsically lipophilic, cross the cell membrane, and are hydrolysed to the acid by the intracellular carboxylesterases. The acid hydrolysis product, being polar, accumulates in the cell since it does not readily cross the cell membrane. Hence the PI3 kinase inhibitory activity of the compound is prolonged and enhanced within the cell. Our copending international Patent Application published as WO 2006/117567 describes general aspects of the strategy of covalent conjugation of amino acid motifs to modulators of intracellular enzymes or receptors. Our copending international Patent Applications published as WO 2006/117549, WO 2006/117548, WO 2006/117570, and WO 2006/117552 describe the application of that strategy to inhibitors of Aurora Kinases and HDAC.

The compounds of the present invention are related to PI3 kinase inhibitors encompassed by the disclosures in International Patent Application WO03072552, but differ therefrom in that the present compounds have the amino acid ester motif referred to above.

Detailed Description of the Invention

According to the invention there is provided a compound of formula (I):

wherein: s is 0 or 1 ;

U is hydrogen or halogen;

X is -(C=O)-; an optionally substituted divalent phenylene, pyridinylene, pyrimidinylene, or pyrazinylene radical; or a bond;

P is optionally substituted C_rC₆ alkyl and Z is -(CH₂)_Z-Y¹-L¹-R; or Z is optionally substituted C₁-C₆ alkyl and P is -(CH₂)_Z-Y¹-L¹-R; Y¹ is a bond, -(C=O)-, -S(O₂)-, -C(=O)O-, -OC(=O)-, -(C=O)NR₃-,

-NR₃(C=O)-, -S(O₂)NR₃-, -NR₃S(O₂)-, or -NR₃(C=O)NR₅-, wherein R₃ and R₅ are independently hydrogen or optionally substituted (C_rC₆)alkyl,

L¹ is a divalent radical of formula -(Alk¹)_m(Q)_n(Alk²)_p- wherein m, n and p are independently O or 1 ,

Q is (i) an optionally substituted divalent mono- or bicyclic carbocyclic or heterocyclic radical having 5 - 13 ring members, or (ii), in the case where p is O, a divalent radical of formula -Q¹-X²- wherein X² is -0-, -S- or NR^A- wherein R^A is hydrogen or optionally substituted C₁-C₃ alkyl, and Q¹ is an optionally substituted divalent mono- or bicyclic carbocyclic or heterocyclic radical having 5 - 13 ring members,

AIk¹ and AIk² independently represent optionally substituted divalent C₃-C₇ cycloalkyl radicals, or optionally substituted straight or branched, C₁-C₆ alkylene, C₂-C₆ alkenylene, or C₂-C₆ alkynylene radicals which may optionally contain or terminate in an ether (-0-), thioether (-S-) or amino (-NR^A-) link wherein R^A is hydrogen or optionally substituted C₁-C₃ alkyl;

z is O or 1 ;

R is a radical of formula (X) or (Y)

wherein

R₁ is a carboxylic acid group (-COOH), or an ester group which is hydrolysable by one or more intracellular carboxylesterase enzymes to a carboxylic acid group; and R₄ is hydrogen; or optionally substituted C_rC₆ alkyl, C₃-C₇ cycloalkyl, aryl or heteroaryl Or -(C=O)R₃, -(C=O)OR₃, or -(C=O)NR₃ wherein R₃ is hydrogen or optionally substituted (C_rC₆)alkyl.

Compounds of formula (I) above may be prepared in the form of salts, especially pharmaceutically acceptable salts, N-oxides, hydrates, and solvates thereof. Any claim to a compound herein, or reference herein to "compounds of the invention", "compounds with which the invention is concerned", "compounds of formula (I)", and the like, includes salts, N-oxides, hydrates, and solvates of such compounds.

Although the above definition potentially includes molecules of high molecular weight, it is preferable, in line with general principles of medicinal chemistry practice, that the compounds with which this invention is concerned should have molecular weights of no more than 600.

In another broad aspect the invention provides the use of a compound of the invention in the preparation of a composition for inhibiting the activity of a PI3 kinase, particularly PI3 kinase α, and PI3 kinase γ.

The compounds with which the invention is concerned may be used for the inhibition of PI3 kinase activity, particularly PI3 kinase qc and PI3 kinase γ activity, ex vivo or in vivo.

In one aspect of the invention, the compounds of the invention may be used in the preparation of a composition for the treatment of neoplastic, immune and inflammatory disorders. For example the compounds may be used in treatment of cell-proliferation disease such as cancers, including bowel cancer, ovarian cancer, head and neck and cervical squamous cancers, gastric and lung cancers, anaplastic oligodendrogliomas, glioblastoma multiforme and medulloblastomas; in inflammatory and immune disease such as rheumatoid arthritis, psoriasis, inflammatory bowel disease, Crohn's disease, ulcerative colitis, chronic obstructive pulmonary disease, asthma, multiple sclerosis, diabetes, atopic dermatitis, graft versus host disease, systemic lupus erythematosus and others; in cardiovascular disorders such as myocardial ischemia, reperfusion injury and others. The foregoing disorders are known to be associated with PI3 Kinase activity. In another aspect, the invention provides a method for the treatment of the foregoing disease types, which comprises administering to a subject suffering such disease an effective amount of a compound of the invention.

A particular subset of the compounds of the invention consists of those of formula (II):

wherein U, P, X, Z and s are as defined in relation to formula (I).

A smaller subset of the compounds of the invention consists of those of formula (II):

wherein L¹ and R are as defined in relation to formula (I).

Terminology

The term "ester" or "esterified carboxyl group" means a group R^XO(C=O)- in which

R^x is the group characterising the ester, notionally derived from the alcohol R^XOH.

As used herein, the term "(C_a-C_b)alkyl" wherein a and b are integers refers to a straight or branched chain alkyl radical having from a to b carbon atoms. Thus when a is 1 and b is 6, for example, the term includes methyl, ethyl, n-propyl, isopropyl, n- butyl, isobutyl, sec-butyl, t-butyl, n-pentyl and n-hexyl. As used herein the term "divalent (C_a-C_b)alkylene radical" wherein a and b are integers refers to a saturated hydrocarbon chain having from a to b carbon atoms and two unsatisfied valences.

As used herein the term "(C_a-C_b)alkenyl" wherein a and b are integers refers to a straight or branched chain alkenyl moiety having from a to b carbon atoms having at least one double bond of either E or Z stereochemistry where applicable. The term includes, for example, vinyl, allyl, 1- and 2-butenyl and 2-methyl-2-propenyl.

As used herein the term "divalent (C_a-C_b)alkenylene radical" means a hydrocarbon chain having from a to b carbon atoms, at least one double bond, and two unsatisfied valences.

As used herein the term "C_a-C_b alkynyl" wherein a and b are integers refers to straight chain or branched chain hydrocarbon groups having from a to b carbon atoms and having in addition one triple bond. In the case where a is 2 and b is 6, this term would include for example, ethynyl, 1-propynyl, 1- and 2-butynyl, 2-methyl-2- propynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 2-hexynyl, 3-hexynyl, 4-hexynyl and 5- hexynyl.

As used herein the term "divalent (C_a-C_b)alkynylene radical" wherein a and b are integers refers to a divalent hydrocarbon chain having from a to b carbon atoms, and at least one triple bond.

As used herein the term "carbocyclic" refers to a mono-, bi- or tricyclic radical having up to 16 ring atoms, all of which are carbon, and includes aryl and cycloalkyl.

As used herein the term "cycloalkyl" refers to a monocyclic saturated carbocyclic radical having from 3-8 carbon atoms and includes, for example, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl.

As used herein the unqualified term "aryl" refers to a mono-, bi- or tri-cyclic carbocyclic aromatic radical, and includes radicals having two monocyclic carbocyclic aromatic rings which are directly linked by a covalent bond. Illustrative of such radicals are phenyl, biphenyl and napthyl. As used herein the unqualified term "heteroaryl" refers to a mono-, bi- or tri-cyclic aromatic radical containing one or more heteroatoms selected from S, N and O, and includes radicals having two such monocyclic rings, or one such monocyclic ring and one monocyclic aryl ring, which are directly linked by a covalent bond. Illustrative of such radicals are thienyl, benzthienyl, furyl, benzfuryl, pyrrolyl, imidazolyl, benzimidazolyl, thiazolyl, benzthiazolyl, isothiazolyl, benzisothiazolyl, pyrazolyl, oxazolyl, benzoxazolyl, isoxazolyl, benzisoxazolyl, isothiazolyl, triazolyl, benztriazolyl, thiadiazolyl, oxadiazolyl, pyridinyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, indolyl and indazolyl.

As used herein the unqualified term "heterocyclyl" or "heterocyclic" includes "heteroaryl" as defined above, and in its non-aromatic meaning relates to a mono-, bi- or tri-cyclic non-aromatic radical containing one or more heteroatoms selected from S, N and O, and to groups consisting of a monocyclic non-aromatic radical containing one or more such heteroatoms which is covalently linked to another such radical or to a monocyclic carbocyclic radical. Illustrative of such radicals are pyrrolyl, furanyl, thienyl, piperidinyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, thiadiazolyl, pyrazolyl, pyridinyl, pyrrolidinyl, pyrimidinyl, morpholinyl, piperazinyl, indolyl, morpholinyl, benzfuranyl, pyranyl, isoxazolyl, benzimidazolyl, methylenedioxyphenyl, ethylenedioxyphenyl, maleimido and succinimido groups.

A "divalent phenylene, pyridinylene, pyrimidinylene, or pyrazinylene radical" is a benzene, pyridine, pyrimidine or pyrazine ring, with two unsatisfied valencies, and includes 1 ,3-phenylene, 1 ,4-phenylene, and the following:

Unless otherwise specified in the context in which it occurs, the term "substituted" as applied to any moiety herein means substituted with up to four compatible substituents, each of which independently may be, for example, (CrC₆)alkyl, (C₂- C₆)alkenyl, (C₂-C₆)alkynyl, (C_rC₆)alkoxy, hydroxy, hydroxy(C_rC₆)alkyl, mercapto, mercapto(C_rC₆)alkyl, (CrCβJalkylthio, halo (including fluoro, bromo and chloro), fully or partially fluorinated (Ci-C₃)alkyl, (C_rC₃)alkoxy or (CrC₃)alkylthio such as trifluoromethyl, trifluoromethoxy, and trifluoromethylthio, nitro, nitrile (-CN), oxo (=0), phenyl, phenoxy, monocyclic heteroaryl or heteroaryloxy with 5 or 6 ring atoms, -COOR^A, -COR^A, -OCOR^A, -SO₂R^A, -CONR^AR^B, -SO₂NR^AR^B, -NR^AR^B, OCONR^AR^B, -NR^BCOR^A, -NR^BCOOR^A, -NR^BSO₂OR^A or -NR^ACONR^AR^B wherein R^A and R^B are independently hydrogen or a (C_rC₆)alkyl group or, in the case where R^A and R^B are linked to the same N atom, R^A and R^B taken together with that nitrogen may form a cyclic amino ring such as a morpholinyl, piperidinyl or piperazinyl ring. Where the substituent is phenyl, phenoxy or monocyclic heteroaryl or heteroaryloxy with 5 or 6 ring atoms, the phenyl or heteroaryl ring thereof may itself be substituted by any of the above substituents except phenyl phenoxy, heteroaryl or heteroaryloxy. An "optional substituent" or "substituent" may be one of the foregoing specified groups.

As used herein the term "salt" includes base addition, acid addition and quaternary salts. Compounds of the invention which are acidic can form salts, including pharmaceutically acceptable salts, with bases such as alkali metal hydroxides, e.g. sodium and potassium hydroxides; alkaline earth metal hydroxides e.g. calcium, barium and magnesium hydroxides; with organic bases e.g. N-methyl-D-glucamine, choline tris(hydroxymethyl)amino-methane, L-arginine, L-lysine, N-ethyl piperidine, dibenzylamine and the like. Those compounds (I) which are basic can form salts, including pharmaceutically acceptable salts with inorganic acids, e.g. with hydrohalic acids such as hydrochloric or hydrobromic acids, sulphuric acid, nitric acid or phosphoric acid and the like, and with organic acids e.g. with acetic, tartaric, succinic, fumaric, maleic, malic, salicylic, citric, methanesulphonic, p-toluenesulphonic, benzoic, benzenesunfonic, glutamic, lactic, and mandelic acids and the like. For a review on suitable salts, see Handbook of Pharmaceutical Salts: Properties, Selection, and Use by Stahl and Wermuth (Wiley-VCH, Weinheim, Germany, 2002).

The term 'solvate' is used herein to describe a molecular complex comprising the compound of the invention and a stoichiometric amount of one or more pharmaceutically acceptable solvent molecules, for example, ethanol. The term 'hydrate' is employed when said solvent is water. Compounds of the invention which contain one or more actual or potential chiral centres, because of the presence of asymmetric carbon atoms, can exist as a number of diastereoisomers with R or S stereochemistry at each chiral centre. The invention includes all such diastereoisomers and mixtures thereof.

The esters of the invention are converted by intracellular esterases to the carboxylic acid. Both the esters and carboxylic acids may have PI3 kinase inhibitory activity in their own right. The compounds of the invention therefore include not only the ester, but also the corresponding carboxylic acid hydrolysis products.

The substituents in formulae (I)

One of P and Z is optionally substituted C₁-C₆ alkyl, while the other is a radical -(CH₂)_Z-Y¹-L¹-R. In one particular case, P is optionally substituted C₁-C₆ alkyl while Z is a radical -(CH₂)₂-Y¹-L¹-R. Optionally substituted C₁-C₆ alkyl radicals P and Z include optionally substituted methyl, ethyl, and n- and iso-propyl. For example P may be methyl.

U may be, for example, hydrogen, fluoro, chloro or bromo. Presently chloro is preferred.

X may be, for example -(C=O)-, a bond, 1 ,3-phenylene, 1 ,4-phenylene, or one of the following divalent radicals:

In the P or Z radical -(CH₂)_Z-Y¹-L¹-R the R part is an alpha amino acid or ester motif, linked via its alpha carbon to L₁ of the linker part -(CH₂)_Z-Y¹-L¹-. That linker part -(CH₂)_Z-Y¹-L¹-. arises as a result of the particular chemistry used to attach the alpha amino acid or ester motif to the rest of the molecule.

The ester group R₁

The ester group R₁ must be one which in the compound of the invention is hydrolysable by one or more intracellular carboxylesterase enzymes to a carboxylic acid group. Intracellular carboxylesterase enzymes capable of hydrolysing the ester group of a compound of the invention to the corresponding acid include the three known human enzyme isotypes hCE-1 , hCE-2 and hCE-3. Although these are considered to be the main enzymes other enzymes such as biphenylhydrolase (BPH) may also have a role in hydrolysing the conjugates. In general, if the carboxylesterase hydrolyses the free amino acid ester to the parent acid it will, also hydrolyse the ester motif when covalently linked to the rest of the molecule. Hence, the broken cell assay described herein provides a straightforward, quick and simple first screen for esters which have the required hydrolysis profile. Ester motifs selected in that way may then be re-assayed in the same carboxylesterase assay when incorporated in the PI3 inhibitor of the invention via the chosen conjugation chemistry, to confirm that it is still a carboxylesterase substrate in that background.

Subject to the requirement that they be hydrolysable by intracellular carboxylesterase enzymes, examples of particular ester groups R-i include those of formula -(C=O)ORr wherein R₇ is R₈R₉R₁₀C- wherein

(i) R₈ is hydrogen or optionally substituted (Ci-C₃)alkyl-(Z¹)_a-[(Ci- C₃)alkyl]_b- or (C₂-C₃)alkenyl-(Z¹)_a-[(C₁-C3)alkyl]b- wherein a and b are independently 0 or 1 and Z¹ is -O-, -S-, or -NR₁₁- wherein R₁₁ is hydrogen or (C_rC₃)alkyl; and R₉ and R₁₀ are independently hydrogen or (C_rC₃)alkyl-;

(ii) R₈ is hydrogen or optionally substituted Ri₂R₁₃N-(Ci-C₃)alkyl- wherein R₁₂ is hydrogen or (CrC₃)alkyl and R₁₃ is hydrogen or (C_rC₃)alkyl; or R₁₂ and R₁₃ together with the nitrogen to which they are attached form an optionally substituted monocyclic heterocyclic ring of 5- or 6- ring atoms or bicyclic heterocyclic ring system of 8 to 10 ring atoms, and R₉ and Ri₀ are independently hydrogen or (C_rC₃)alkyl-;or

(iii) R₈ and R₉ taken together with the carbon to which they are attached form an optionally substituted monocyclic carbocyclic ring of from 3 to 7 ring atoms or bicyclic carbocyclic ring system of 8 to 10 ring atoms, and R₁₀ is hydrogen.

Within these classes, R₁₀ is often hydrogen. Specific examples of R₇ include methyl, ethyl, n- or iso-propyl, n-, sec- or tert-butyl, cyclohexyl, allyl, phenyl, benzyl, 2-, 3- or 4-pyridylmethyl, N-methylpiperidin-4-yl, tetrahydrofuran-3-yl or methoxyethyl. Currently preferred is where R₇ is cyclopentyl.

Macrophages are known to play a key role in inflammatory disorders through the release of cytokines in particular TNFα and IL-1 (van Roon et al., Arthritis and Rheumatism , 2003, 1229-1238). In rheumatoid arthritis they are major contributors to the maintenance of joint inflammation and joint destruction. Macrophages are also involved in tumour growth and development (Naldini and Carraro, Curr Drug Targets lnflamm Allergy ,2005, 3-8 ). Hence agents that selectively target macrophage cell proliferation could be of value in the treatment of cancer and autoimmune disease. Targeting specific cell types would be expected to lead to reduced side-effects. The inventors have discovered a method of targeting PI3 Kinase inhibitors to macrophages which is based on the observation that the way in which the esterase motif is linked to the PI3 Kinase inhibitor determines whether it is hydrolysed, and hence whether or not it accumulates in different cell types. Specifically it has been found that macrophages contain the human carboxylesterase hCE-1 whereas other cell types do not. In the general formula (I) when the nitrogen of the esterase motif is substituted but not directly bonded to a carbonyl group, the ester will only be hydrolysed by hCE-1 and hence the PI3 Kinase inhibitors will only accumulate in macrophages. Herein, unless "monocyte" or "monocytes" is specified, the term macrophage or macrophages will be used to denote macrophages (including tumour associated macrophages) and/or monocytes.

The group R^

The group R₄ is present in the compounds of the invention when R in formula (I) is a radical of formula (X)

As mentioned above, if the modulator is intended to act only in cell types where hCE- 1 is present, such as macrophages, the amino group of the carboxylesterase motif should be directly linked to a group other than carbonyl. In such cases R₄ may be optionally substituted C₁-C₆ alkyl, C₃-C₇ cycloalkyl, aryl or heteroaryl such monocyclic heteroaryl having 5 or 6 ring atoms, for example methyl, ethyl, n-or isopropyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl, or pyridyl. In cases where macrophage specificity is not required, R₄ may be hydrogen or -(C=O)R₃, wherein R₃ is optionally substituted C₁-C₆ alkyl such as methyl, ethyl, n-or isopropyl, or n-, iso- or sec-butyl, C₃-C₇cycloalkyl such as cyclopropyl, cyclopentyl, cyclohexyl, phenyl, pyridyl, thienyl, phenyl(C_rC₆ alkyl)-, thienyl(C_rC₆ alkyl)- or pyridyl(C_rC₆ alkyl)- such as benzyl, 4- methoxyphenylmethylcarbonyl, thienylmethyl or pyridylmethyl.

R₄ may also be, for example -(C=O)OR₃, or -(C=O)NHR₃ wherein R₃ is hydrogen or optionally substituted (C_rC₆)alkyl such as methyl, ethyl, or n-or isopropyl.

For compounds of the invention which are to be administered systemically, esters with a slow rate of esterase cleavage are preferred, since they are less susceptible to pre-systemic metabolism. Their ability to reach their target tissue intact is therefore increased, and the ester can be converted inside the cells of the target tissue into the acid product. However, for local administration, where the ester is either directly applied to the target tissue or directed there by, for example, inhalation, it will often be desirable that the ester has a rapid rate of esterase cleavage, to minimise systemic exposure and consequent unwanted side effects. If a carbon atom to which the group R is attached is unsubstituted, ie R is attached to a methylene (-CH₂)- radical, then the esters tend to be cleaved more rapidly than if that carbon is substituted, or is part of a ring system such as a phenyl or cyclohexyl ring.

The radical -L¹-Y¹-rCH_?1-

This radical (or bond) arises from the particular chemistry strategy chosen to link the amino acid ester motif R to the inhibitor. Clearly the chemistry strategy for that coupling may vary widely, and thus many combinations of the variables Y¹, L¹, and z are possible. However, when the inhibitor is bound to the enzyme at its active site, the amino acid ester motif generally extends in a direction away from that pocket, and thus minimises or avoids interference with the binding mode of the inhibitor. Hence the precise combination of variables making up the linking chemistry between the amino acid ester motif and the inhibitor will often be irrelevant to the primary binding mode of the compound as a whole. The broken cell data quoted below (see Measurement of Biological Activities .Table 1 ) confirms that a wide diversity of amino acid ester motifs, linked by many linker chemistries, are hydrolysed by intracellular carboxyl esterases. In addition, as mentioned above, our copending international Patent Application published as WO 2006/117567 describes general aspects of the strategy of covalent conjugation of amino acid motifs to modulators of intracellular enzymes or receptors, and our copending international Patent Applications published as WO 2006/117549, WO 2006/117548, WO 2006/117570, and WO 2006/117552 describe the application of that strategy to inhibitors of Aurora Kinases and HDAC.

With the foregoing general observations in mind, taking the variables making up the radical -L¹-Y¹-[CH₂]_Z- in turn:

z may be 0 or 1 , so that a methylene radical linked to the inhibitor is optional;

Y¹ may be, for example, -NR₃-, -S-, -O-, -C(=O)NR₃-, - NR₃C(=O)-, or -C(=O)O-, wherein R₃ is hydrogen or optionally substituted C₁-C₆ alkyl such as -CH₂CH₂OH;

In the radical L¹, examples of AIk¹ and AIk² radicals, when present, include — CH₂-, — CH₂CH₂- — CH₂CH₂CH₂-, — CH₂CH₂CH₂CH₂-, — CH=CH-, -CH=CHCH₂-, -CH₂CH=CH-, CH₂CH=CHCH₂-, -C≡C-, -C=CCH₂-, CH₂C=C- , and CH₂C≡CCH₂. Additional examples of AIk¹ and AIk² include -CH₂W-, -CH₂CH₂W- -CH₂CH₂WCH₂-, -CH₂CH₂WCH(CH₃)-, -CH₂WCH₂CH₂-, -CH₂WCH₂CH₂WCH₂-, and -WCH₂CH₂- where W is -O-, -S-, -NH-, -N(CH₃)-, or -CH₂CH₂N(CH₂CH₂OH)CH₂-. Further examples of AIk¹ and AIk² include divalent cyclopropyl, cyclopentyl and cyclohexyl radicals.

In L¹, when n is 0, the radical is a hydrocarbon chain (optionally substituted and perhaps having an ether, thioether or amino linkage). Presently it is preferred that there be no optional substituents in L¹. When both m and p are 0, L¹ is a divalent mono- or bicyclic carbocyclic or heterocyclic radical with 5 - 13 ring atoms (optionally substituted). When n is 1 and at least one of m and p is 1 , L¹ is a divalent radical including a hydrocarbon chain or chains and a mono- or bicyclic carbocyclic or heterocyclic radical with 5 - 13 ring atoms (optionally substituted). When present, Q may be, for example, a divalent phenyl, naphthyl, cyclopropyl, cyclopentyl, or cyclohexyl radical, or a mono-, or bi-cyclic heterocyclicl radical having 5 to13 ring members, such as piperidinyl, piperazinyl, indolyl, pyridyl, thienyl, or pyrrolyl radical, but 1 ,4- phenylene is presently preferred. Specifically, in some embodiments of the invention, in L¹, m and p may be 0 with n being 1. In other embodiments, n and p may be 0 with m being 1. In further embodiments, m, n and p may be all 0. In still further embodiments m may be 0, n may be 1 with Q being a monocyclic heterocyclic radical, and p may be 0 or 1. AIk¹ and AIk², when present, may be selected from -CH₂-, -CH₂CH₂-, and -CH₂CH₂CH₂- and Q may be 1 ,4-phenylene.

Specific preferred examples of the radical -L¹ -Y¹ -[CH₂]Z- include -(CH₂)₃NH-, - CH₂C(=O)NH-, -CH₂CH₂C(=O)NH-,-CH₂C(O)O-, -CH₂S-, -CH₂CH₂C(O)O-, -(CHz)₄NH-, -CH₂CH₂S-, -CH₂O, -CH₂CH₂O-,

The compounds of the invention may be prepared by a number of processes described in the Examples hereinafter. In the reactions described below, it may be necessary to protect reactive functional groups, for example hydroxyl, amino and carboxyl groups, where these are desired in the final product, to avoid their unwanted participation in the reactions [see for example Greene, T.W., "Protecting Groups in Organic Synthesis", John Wiley and Sons, 1999]. Conventional protecting groups may be used in conjunction with standard practice.

Thus, many amino acid esters of the invention may be prepared by methods analogous to that set forth in Scheme 1.

HCI or 20% TFA In ether In DCM

(IA)

Scheme 1

Esters of formula (IA) where the ester radical is a cyclopentyl group may be prepared by treatment of the analogous carbamates of formula (2) with trifluoroacetic acid in a chlorinated solvent such as dichloromethane at ambient temperature. In another aspect of the invention where the ester radical is a tert-butyl group, the removal of the tert-butyl carbamate protecting group may be achieved in ethereal HCI without concomitant cleavage of the tert-butyl ester substituent. The carbamates (2) may be prepared by the coupling of an appropriately substituted carboxylic acid of general formula (3) with the aminothiazole (Intermediate A) [WO03072552], using a carbodiimide such as EDC and HOBt in an aprotic solvent such as DMF. It will be seen by those skilled in the art that several methods of amide bond formation may be applicable to this process. [March's Advanced Organic Chemistry [John Wiley and Sons, 1992]. Carboxylic acids of general formula (3) may be prepared, but not limited, to methods shown in Scheme 2. / DMF

10% Pd/C H₂ gas EtOH

(3)

Scheme 2

Other amino acids of the invention may be prepared by the treatment of cyclopentyl esters of general formula (IA) with an aqueous mineral base such as sodium or lithium hydroxide in the presence of a miscible organic co-solvent such as tetrahydrofuran or methanol, as shown in Scheme 3.

(IA) (IB)

Scheme 3

Other amino acid esters of the invention may be prepared by methods analogous to that described in Scheme 4. Thus, compounds of general formula (IC) may be prepared by a reductive amination process, involving the reaction of (IA) with an aldehyde or ketone (such as for example cyclohexanone) in the presence of sodium cyanoborohydride in methanol and glacial acetic acid at ambient temperature [see for example Borsch et al, J. Am. Chem. Soc, 1971 , 93, 2897]. It will be recognized by those skilled in the art that this process will apply to any appropriately substituted aldehyde, ketone or cyclic ketone and that a number of reducing agents may be employed. Hydrolysis of esters of formula (IC) to the amino acid derivatives of formula (ID) may be performed by hydrolysis using a mineral base such as potassium or sodium hydroxide, followed by acidic work up as shown in scheme 4. Cyclohexanone NaCHBH₃, AcOH, EtOH _C|

NaOH₁, THF

(ID)

Scheme 4

Many esters of general formula IE may be prepared by methods analogous to that shown in Scheme 5.

Scheme 5

Thus esters of general formula (IA) may be treated with an acylating agent such as acetyl chloride or acetic anhydride in the presence of an organic base such as triethylamine to give esters of general formula (IE).

Other amino acid esters of the invention may be prepared by methods analogous to that outlined in Scheme 6.

ornithate ester, Et₃N, DMF

("F) (8)

Scheme 6

Thus the aminothiazole may be reacted with carbonyldiimidazole to give the intermediate (7) in an inert halogenated solvent such as dichloromethane. The resulting imidazole carboxamide may then be reacted with an appropriately protected ornithate ester, such as cyclopentyl Λ/²-(tert-butoxycarbonyl)ornithate, in a polar aprotic solvent such as DMF in the presence of triethylamine to give the protected urea derivative (8). Deprotection of the tert-butoxycarbamate protected amino ester under acidic conditions with trifluoroacetic acid or aqueous hydrochloric acid in a water miscible co-solvent such as THF or 1 ,4-dioxane can be utilized to afford the amino acid esters of general formula (IF).

Other amino acid esters of the invention may be prepared by methods analogous to that of Scheme 7.

Scheme 7

Thus the benzyl ether (9) may be prepared by the reaction of (7) with 4- benzyloxyaniline in anhydrous DMF in the presence of an organic base such as triethylamine. Benzyl ethers such as (9) may then be converted to the corresponding phenols as exemplified by (10) through treatment with thioanisol in trifluoroacetic acid. N-Protected amino acid esters such as (11 ) may be prepared by the alkylation of phenol (10) with a reagent such as cyclopentyl (2S)-4-bromo-2-[(tert- butoxycarbonyl)amino]butanoate in the presence of inorganic base such as potassium or caesium carbonate in an aprotic solvent such as DMF. Amino acid ester (11 ) may then be treated with trifluoroacetic acid to give the amino acid (IG).

Other amino acid esters of the invention may be prepared by methods analogous to that of Scheme 8.

HCI Dioxane

(IH)

Scheme 8

Thus the sulphonyl chloride (12) may be reacted with a reagent such as cyclopentyl Λ/²-(terf-butoxycarbonyl)ornithinate in the presence of aqueous mineral base such as sodium carbonate in a water miscible solvent such as 1,4-dioxane to give the sulphonamide (13). The bromoketone of formula (14) may be prepared by the reaction of (13) with bromine in a solvent such as 1 ,4-dioxane. The intermediate aminothiazole (15) in turn may be prepared by the reaction of (14) with acetylthiourea under conditions of reflux in ethyl alcohol. The resulting tert-butylcarbamate (16) may be deprotected under acidic conditions, such as aqueous hydrochloric acid in 1,4- dioxane, to give amino acid ester (1 H).

As mentioned above, the compounds with which the invention is concerned are inhibitors of the PI3 kinase family, particularly PI3 kinase qc and/or PI3 kinase γ, and are therefore of use in the treatment of neoplastic, immune and inflammatory disease in humans and other mammals.

It will be understood that the specific dose level for any particular patient will depend upon a variety of factors including the activity of the specific compound employed, the age, body weight, general health, sex, diet, time of administration, route of administration, rate of excretion, drug combination and the severity of the particular disease undergoing treatment. Optimum dose levels and frequency of dosing will be determined by clinical trial.

The compounds with which the invention is concerned may be prepared for administration by any route consistent with their pharmacokinetic properties. The orally administrable compositions may be in the form of tablets, capsules, powders, granules, lozenges, liquid or gel preparations, such as oral, topical, or sterile parenteral solutions or suspensions. Tablets and capsules for oral administration may be in unit dose presentation form, and may contain conventional excipients such as binding agents, for example syrup, acacia, gelatin, sorbitol, tragacanth, or polyvinylpyrrolidone; fillers for example lactose, sugar, maize-starch, calcium phosphate, sorbitol or glycine; tabletting lubricant, for example magnesium stearate, talc, polyethylene glycol or silica; disintegrants for example potato starch, or acceptable wetting agents such as sodium lauryl sulphate. The tablets may be coated according to methods well known in normal pharmaceutical practice. Oral liquid preparations may be in the form of, for example, aqueous or oily suspensions, solutions, emulsions, syrups or elixirs, or may be presented as a dry product for reconstitution with water or other suitable vehicle before use. Such liquid preparations may contain conventional additives such as suspending agents, for example sorbitol, syrup, methyl cellulose, glucose syrup, gelatin hydrogenated edible fats; emulsifying agents, for example lecithin, sorbitan monooleate, or acacia; nonaqueous vehicles (which may include edible oils), for example almond oil, fractionated coconut oil, oily esters such as glycerine, propylene glycol, or ethyl alcohol; preservatives, for example methyl or propyl p-hydroxybenzoate or sorbic acid, and if desired conventional flavouring or colouring agents.

For topical application to the skin, the drug may be made up into a cream, lotion or ointment. Cream or ointment formulations which may be used for the drug are conventional formulations well known in the art, for example as described in standard textbooks of pharmaceutics such as the British Pharmacopoeia. For topical application by inhalation, the drug may be formulated for aerosol delivery for example, by pressure-driven jet atomizers or ultrasonic atomizers, or preferably by propellant-driven metered aerosols or propellant-free administration of micronized powders, for example, inhalation capsules or other "dry powder" delivery systems. Excipients, such as, for example, propellants (e.g. Frigen in the case of metered aerosols), surface-active substances, emulsifiers, stabilizers, preservatives, flavorings, and fillers (e.g. lactose in the case of powder inhalers) may be present in such inhaled formulations. For the purposes of inhalation, a large number of apparata are available with which aerosols of optimum particle size can be generated and administered, using an inhalation technique which is appropriate for the patient. In addition to the use of adaptors (spacers, expanders) and pear-shaped containers (e.g. Nebulator®, Volumatic®), and automatic devices emitting a puffer spray (Autohaler®), for metered aerosols, in particular in the case of powder inhalers, a number of technical solutions are available (e.g. Diskhaler®, Rotadisk®, Turbohaler® or the inhalers for example as described in European Patent Application EP 0 505 321 ).

For topical application to the eye, the drug may be made up into a solution or suspension in a suitable sterile aqueous or non aqueous vehicle. Additives, for instance buffers such as sodium metabisulphite or disodium edeate; preservatives including bactericidal and fungicidal agents such as phenyl mercuric acetate or nitrate, benzalkonium chloride or chlorhexidine, and thickening agents such as hypromellose may also be included.

The active ingredient may also be administered parenterally in a sterile medium. Depending on the vehicle and concentration used, the drug can either be suspended or dissolved in the vehicle. Advantageously, adjuvants such as a local anaesthetic, preservative and buffering agent can be dissolved in the vehicle.

For several of the conditions treatable by compounds of the invention, one advantage lies in their property of accumulating in lung tissue, resulting in reduced systemic exposure relative to the analogous PI3 inhibitor not conjugated to the amino acid ester motif. Although it is well known that agents can be given directly to the lung using inhalation methodologies, such agents still enter the systemic circulation. This can result in undesirable side effects, and can limit the dose and range of agents that can be used to treat lung disorders. Following delivery to the lung of an agent to which a hydrolysable esterase motif is attached, the neutral ester species is taken up by lung tissue where, depending on the nature of the esterase motif, it is rapidly cleaved to the acid which, as a consequence of it being a charged species, is retained in the lung tissue for a longer period of time than the neutral ester. Thus the agent is concentrated in the lung tissue and systemic exposure is reduced.

The following examples illustrate the preparation and properties of some specific compounds of the invention. Al! temperatures are in ⁰C. The following abbreviations are used:

MeOH = methanol

EtOH = ethanol

EtOAc = ethyl acetate

Boc = tert-butoxycarbonyl

DCM = dichloromethane

DMF = dimethylformamide

DMSO = dimethyl sulfoxide

TFA = trifluoroacetic acid

THF = tetrahydrofuran

Na₂CO₃ = sodium carbonate

HCI = hydrochloric acid

DIPEA = diisopropylethylamine

NaH = sodium hydride

NaOH = sodium hydroxide

NaHCO₃= sodium hydrogen carbonate

Pd/C = palladium on carbon

TME = tert-butyl methyl ether

N₂ = nitrogen

PyBop = benzotriazole-1-yl-oxy-tris-pyrrolidino-phosphonium hexafluorophosphate

Na₂SO₄ = sodium sulphate

Et₃N = triethylamine

NH₃ = ammonia

TMSCI = trimethylchlorosilane

NH₄CI = ammonium chloride

LiAIH₄ = lithium aluminium hydride pyBrOP = bromo-tris-pyrrolidino phosphoniumhexafluorophosphate

MgSO₄ = magnesium sulfate

"BuLi = n-butyllithium CO₂ = carbon dioxide

EDC = Λ/-(3-Dimethylaminopropyl)-Λ/'-ethylcarbodiimide hydrochloride

Et₂O = diethyl ether

LiOH = lithium hydroxide

HOBt = 1-hydroxybenzotriazole

ELS = Evaporative Light Scattering

TLC = thin layer chromatography ml = milliliter(s) g = gram(s) mg = milligram(s) mol = mole(s) mmol = millimole(s)

LCMS = high performance liquid chromatography/mass spectrometry

NMR = nuclear magnetic resonance

RT = room temperature

Microwave irradiation was carried out using a CEM Discover focused microwave reactor. Solvents were removed using a GeneVac Series I without heating or a Genevac Series Il with VacRamp at 3O⁰C or a Buchi rotary evaporator. Purification of compounds by flash chromatography column was performed using silica gel, particle size 40-63 μm (230-400 mesh) obtained from Silicycle. Purification of compounds by preparative HPLC was performed on Gilson systems using reverse phase ThermoHypersil-Keystone Hyperprep HS C18 columns (12 μm, 100 X 21.2 mm), gradient 20-100% B (A= water/ 0.1% TFA, B= acetonitrile/ 0.1% TFA) over 9.5 min, flow = 30 ml/min, injection solvent 2:1 DMSO:acetonitrile (1.6 ml), UV detection at 215 nm.

¹H NMR spectra were recorded on a Bruker 400 MHz AV or a Bruker 300 MHz AV spectrometer in deuterated solvents. Chemical shifts (δ) are in parts per million. Thin- layer chromatography (TLC) analysis was performed with Kieselgel 60 F_2S4 (Merck) plates and visualized using UV light.

Analytical HPLCMS was performed on Agilent HP1100, Waters 600 or Waters 1525 LC systems using reverse phase Hypersil BDS C18 columns (5 μm, 2.1 X 50 mm), gradient 0-95% B (A= water/ 0.1 % TFA, B= acetonitrile/ 0.1% TFA) over 2.10 min, flow = 1.0 ml/min. UV spectra were recorded at 215 nm using a Gilson G1315A Diode Array Detector, G1214A single wavelength UV detector, Waters 2487 dual wavelength UV detector, Waters 2488 dual wavelength UV detector, or Waters 2996 diode array UV detector. Mass spectra were obtained over the range m/z 150 to 850 at a sampling rate of 2 scans per second or 1 scan per 1.2 seconds using Micromass LCT with Z-spray interface or Micromass LCT with Z-spray or MUX interface. Data were integrated and reported using OpenLynx and OpenLynx Browser software. The following intermediates were employed during the synthesis of the examples described herein:

Intermediate D Intermediate E Intermediate F

Intermediate G Intermediate H

Intermediate A 5-r4-Chloro-3-(methylsulfonyl)phertyl1-4-methyl-1 ,3-thiazol-2- amine

Intermediate A was prepared according to the methodology described in WO/03072552 and WO/04078754. LCMS purity 91 %, m/z 303 [M+H]⁺, ¹H NMR (300 MHz, CD₃OD) δ: 2.35 (3H, s, CH₃), 3.35 (3H, s, CH₃), 7.75-7.85 (2H, m, Ar), 8.15 (1 H₁ S₁ Ar).

Intermediate B 2-Chloro-5-(2-oxopropyl)benzenesulfonyl chloride 4-Chlorophenylacetone (4g, 23.7mmol) was added dropwise to chlorosulfonic acid (30ml) at -10 ⁰C. The reaction was allowed to warm to RT and stirred for 36h. Upon completion, the reaction was quenched by slow addition to crushed ice (500ml). The aqueous solution was then extracted with EtOAc (3 x 100ml) and the combined organics were dried (MgSO₄) and concentrated in vacuo to afford the title compound (6.7g, 98%). m/z 289 [M+Na]⁺, ¹H NMR (300 MHz, CDCI₃) δ: 7.96 (1H, d, J=2.1 Hz), 7.62 (1 H, d, J=8.7 Hz), 7.49 (1 H, dd, J=2.1 , 8.7 Hz), 3.86 (2H, s), 2.30 (3H, s).

Intermediate C (4S)-4-r(tert-butoxycarbonyl)amino1-5-(cycIopentyloxy)-5- oxopentanoic acid

A mixture of 1-cyclopentyl 5-benzyl (2S)-2-[(tert-butoxycarbonyl)amino] pentanedioate (1.3g, 3.20mmol), and 10% Pd/ C (0.5g) in EtOH (150ml) was stirred under H₂ (balloon) at RT for 4h, after which time LC showed completion of reaction. The reaction mixture was filtered through a pad of celite, washed with EtOH (20ml) and concentrated in vacuo to give a white solid. To remove residual EtOH the solid was dissolved in toluene/ THF mixture (5/1) (20ml) and concentrated in vacuo. Yield= 0.8g, 79%. ¹H NMR (400 MHz, MeOD), δ: 1.35 (9H, s, t-Bu), 1.60-2.10 (1OH, m, 5xCH₂), 4.05 (1 H, m, CH), 5.20 (1 H, m, CH).

The benzyl ester used as starting material in the above process was prepared as follows

To a stirred solution of (2S)-5-(benzyloxy)-2-[(tert-butoxycarbonyl)amino]-5- oxopentanoic acid (5g, 14.8mmol) in a mixture of DCM (50ml) and DMF (30ml) at 0 ⁰C was added cyclopentanol (2.7ml, 29.6mmol), EDC (4.25g, 22.2mmol) and DMAP (0.18g, 1.48mmol). Stirring was continued at RT overnight, after which time LCMS showed completion of reaction. DCM was removed under reduced pressure. The reaction mixture was diluted with EtOAc (200ml), washed with water (100ml), 1 M aq HCI (50ml) followed by sat aq NaHCO₃ (50ml). The EtOAc layer dried (Na₂SO₄), filtered and concentrated in vacuo to give a viscous oil which solidified on standing overnight. Trituration with Et₂O (2 x 10ml) afforded the product as a white solid (43.78g, 80%). LC purity= 94%, m/z 406 [M+H]

Intermediates D and E were prepared by the same methodology described for Intermediate E, starting from the analogous protected amino acids.

Intermediate D (3S)-3-r(te/-f-Butoxycarbonyl)amino1-4-fcvclopentyloxy)-4- oxobutanoic acid m/z 302 [M+H]⁺

Intermediate E (4/?)-4-rfte/^*f-Butoxycarbonyl)amino1-5-(cyclopentyloxy)-5- oxopentanoic acid

¹H NMR (400 MHz, CD₃OD) δ: 1.36 (9H, S, t-Bu), 1.63-2.08 (1OH, m, 5xCH₂), 4.01 (1 H, m, CH), 5.19 (1 H, m, CH).

Intermediate F Cyclopentyl /V-r(benzyloxy)carbonyll-6-hvdroxy-6-oxo-L- norleucinate

Intermediate D was prepared from the N-Cbz protected t-butyl ester aminoacid. Therefore stage 2 deprotection was carried out using 4M HCI in dioxane. m/z 364.2 [M+H]⁺.

Intermediate G Cyclopentyl /V²-(fe/^*f-butoxycarbonyl)ornithinate

Cyclopentyl Λ/⁵-[(benzyloxy)carbonyl]-W²-(tert-butoxycarbonyl)-L-ornithinate (863mg, 1.95mmo!) was dissolved in EtOAc and the solution degassed. Pd(OH)₂ was added and the mixture stirred under H₂ atmosphere (balloon) for 2h. The catalyst was then removed by filtration through celite and washed with EtOAc, DCM and MeOH. The solvents were then removed in vacuo to afford the product (479mg, 80%). LCMS purity 86%, m/z 301.2 [M+H]⁺, ¹H NMR (300 MHz₁ CDCI₃) δ: 5.78 (1H, br s), 5.44 (1 H₁ br s), 4.36 (1 H, br s), 4.05 (1 H, m), 3.35 (2H, t), 2.51 (1 H, m), 1.96 (2H₁ m), 1.69-1.79 (4H, m), 1.53-1.69 (6H, m), 1.47 (9H, s).

The cyclopentyl ester used in the above process was prepared as follows

To a solution of Λ/⁵-[(benzyloxy)carbonyl]-Λ/²-(terf-butoxycarbonyl)ornithine (2g, 5.46mmol) in DCM (60ml) was added cyclopentanol (989μl, 10.9mmol), DMAP (67mg, 0.55mmol) and EDC (1.15g, 6.01 mmol). The reaction mixture was stirred at RT for 18h under nitrogen atmosphere. This was then poured into waster (50ml) and extracted with DCM (2 x 50ml). The organic was washed with 1 M HCI_aq (50ml) then sat NaHCO_3(aq) (50ml) then dried (MgSO₄) and concentrated in vacuo. The crude was purified by flash chromatography eluting with 2% MeOH in DCM (1.74g, 73%). LCMS purity 100%, m/z 457.2 [M+Na]\ 1 H NMR (300 MHz, CDCI₃) δ: 7.33-7.38 (5H, m), 5.22 (1H, br t), 5.11-5.20 (3H₁ m), 4.85 (1H, br s), 3.25 (2H, q), 1.83-1.87 (2H, m), 1.53-1.80 (1OH, m), 1.46 (9H, s).

Intermediate H (2S)-4-bromo-2-r(tert-butoxycarbonyl)aminolbutanoate

TBDMSiCI, DBU, MeCN BoC₂O, Et₃N, DCM

Stage 1 Stage 2

Cyclopentanol

Stage 3 EDC, DMAP DCM

Intermediate H

Stage 1

To a suspension of L-homoserine (1g, 8.4mmol) in MeCN (10ml) at 0 ⁰C was added 1 ,8-diazabicyclo[5.4.0]undec-7-ene (1.32ml, 8.8mmol). tert-Butyl-dimethyl-silyl chloride (1.33g, 8.8mmol) was then added portionwise over 5 minutes and the reaction mixture allowed to warm to RT and stirred for 16h. A white precipitate had formed which was filtered off and washed with MeCN before drying under vacuum. The title compound was isolated as a white solid (1.8g, 92%). ¹H NMR (500 MHz, d₆- DMSO) δ: 7.5 (1 H, br s), 3.7 (1 H, m), 3.35 (4H, br m), 1.95 (1 H, m), 1.70 (1H, m), 0.9 (9H, s), 0.1 (6H, s).

Stage 2

A suspension of stage 1 product (1.8g, 7.7mmol) in DCM (100ml) at 0 ⁰C was treated with Et₃N (2.15ml, 15.4mmol) and di-terf-butyl dicarbonate (1.77g, 8.1mmol). The reaction mixture was stirred at RT for 16h. The DCM was removed under reduced pressure and the mixture was partitioned between EtOAc and brine. The EtOAc layer was dried (MgSO₄) and evaporated under reduced pressure. The crude product was taken forward to the next stage without further purification (2.53g, 99%). ¹H NMR (500 MHz, CDCI₃) δ: 7.5 (1 H, br s), 5.85 (1 H, d, ,7=6.5 Hz), 4.3 (1 H, m), 3.75 (2H, m), 1.95 (2H, m), 1.40 (9H, s), 0.85 (9H, s), 0.1 (6H, s).

Stage 3

To a solution of stage 2 product (2.53g, 7.6mmol) in DCM (50ml) at 0 ⁰C was added cyclopentanol (1.39ml, 15.3ml), EDC (1.61g, 8.4mmol) and DMAP (0.093g, 0.76mmol). The reaction mixture was stirred for 16h at RT before evaporation under reduced pressure. The crude residue was dissolved in EtOAc (100ml) and washed with 1 M HCI_aq, 1 M Na₂CO_3(aq) and brine. The organic layer was then dried (MgSO₄) and evaporated under reduced pressure. The product was purified by column chromatography eluting with ethyl acetate/heptane (1 :4) (2.24g, 73%). LCMS purity 100%, m/z 402.5 [M+H]⁺, ¹H NMR (250 MHz, CDCI₃) δ: 5.2 (1H, d, J=6.3 Hz), 5.15 (1 H, m), 4.2 (1 H, m), 3.6 (2H, m), 2.0 (1 H, m), 1.95-1.55 (9H, br m), 1.4 (9H, s), 0.85 (9H, s), 0.1 (6H, s).

Stage 4

Stage 3 product (1.57g,3.9mmol) was dissolved in acetic acid :TH F: water (3:1 :1 , 100ml). The reaction mixture was stirred at 30 ⁰C for 16h. EtOAc (200ml) was added and washed with 1 M Na₂CO_3(aq), 1M HCI_aq and brine. The EtOAc extracts were dried (MgSO₄) and evaporated under reduced pressure to give the product as a clear oil which Drystallized on standing (1.Og, 95%). LCMS purity 100%, m/z 310.3 [M+Na]⁺, ¹H NMR (250 MHz, CDCI₃) δ: 5.4 (1 H, d, J=6.5 Hz), 5.2 (1 H, m), 4.4 (1 H, m), 3.65 (2H, m), 2.15 (1 H, m), 1.9-1.55 (9H, br m), 1.45 (9H, s). Stage 5 (Intermediate H)

To a slurry of N-bromo succinimide (1.86g, 10.4mmol) in DCM (16.2 ml) was added a solution of triphenyl phosphine (2.56g, 9.74mmol) in DCM (7.2 ml). The solution was stirred for a further 5 minutes after addition. Pyridine (338μl, 4.18mmol) was added, followed by a solution of stage 4 product (1.Og, 3.48mmol) in DCM (8.8ml). The solution was stirred for 18h, concentrated in vacuo and the residual solvent azeotroped with toluene (3 x 16ml). The residue was triturated with Et₂O (10ml) and EtOAc:heptane (1 :9, 2 x 10ml). The combined ether and heptane solutions were concentrated onto silica and purified by column chromatography eluting with ethyl acetate/heptane (1 :9 - 2:8) to provide the title compound (1.02g,84%). ¹H NMR (300 MHz, CDCI₃) δ: 5.3 - 5.05 (2H₁ m), 4.45 - 4.3 (1 H, m), 3.45 (2H, t, J=7.3 Hz), 2.50 - 2.30 (1 H, m), 2.25 - 2.10 (1 H, m), 1.95 - 1.60 (8H, br m), 1.47 (9H, s).

Examples

The following are representative examples of the compounds claimed by the invention.

Example 1 Cvclopentyl /V²-(ferf-butoxycarbonyl)-Λ/-(5-r4-chloro-3-(methyl sulfonyl)phenvn-4-methyl-1,3-thiazol-2-yl)-L-glutaminate trifluoroacetate

A solution of cyclopentyl /V²-(te/t-butoxycarbonyl)-Λ/-{5-[4-chloro-3- (methylsulfonyl)phenyl]-4-methyl-1 ,3-thiazol-2-yl}-l_-glutaminate (140mg, 0.233mmol) in 20% TFA/ DCM (2ml) was allowed to stand at RT for 3h. After completion the reaction mixture was concentrated in vacuo to give the desired product (143mg, 100%). LCMS purity 97%, m/z 500/502 [M⁺+H], ¹H NMR (400 MHz, MeOD), δ: 1.35- 1.85 (8 H, m, 4 x CH₂), 2.00-2.20 (2 H, m, CH₂), 2.25 (3 H, s, CH₃), 2.60 (2 H, m, CH₂), 3.20 (3 H, s, CH₃), 3.85-4.00 (1 H, m, CH), 5.10 (1 H, m, CH), 7.50-7.65 (2 H, m, Ar), 7.95 (1 H, s, Ar). The carbamate used as starting material in Example 1 was prepared as follows

To a stirred mixture of Intermediate 1 (208mg, 0.66mmol), EDC (190mg, 0.99mmol) and HOBt (107mg, 0.79mmol) in DMF (1.5ml) was added dropwise a solution of Intermediate A 5-(4-chloro-3-methanesulfonylphenyl)-4-methylthiazol-2-ylamine, (200mg, 0.66mmol) in DMF (1.5ml) at RT. Triethylamine (0.138ml,0.99mmol) was added and stirring was continued for 18h. LCMS indicated 70% conversion to product. The reaction mixture was diluted with water (10ml) and extracted with EtOAc (15ml). EtOAc layer was washed with water (10ml), dried (Na₂SO₄), filtered and concentrated in vacuo. Purification by preparative TLC (70% EtOAc/ heptane, R_f 0.5) gave the desired material (160mg, 40%). LCMS purity 91%, m/z 600/602 [M⁺+H], ¹H NMR (400 MHz, DMSO), δ: 1.45-1.55 (9H, s, 3 x CH₃), 1.65-2.15 (10 H, m, 5 x CH₂), 2.45 (3 H, s, CH₃), 2.70 (2 H, m, CH₂), 3.45 (3 H, s, CH₃), 4.10-4.25 (1 H, m, CH), 5.25 (1 H, m, CH), 7.75-7.90 (2 H, m, Ar), 8.25 (1 H, s, Ar).

The following examples were prepared by similar methods described for Example 1.

Example 2 Cyclopentyl ΛK5-r4-chloro-3-(methylsulfonyl)phenyll-4-rnethyl-'1,3- thiazol-2-vD-L-asparaginate trifluoroacetate

From, cyclopentyl Λ/²-(teAf-butoxvcarbonvl)-N-{5-r4-chloro-3-(methylsulfonyl)phenyll- 4-methyl-1.3-thiazol-2-yl)-L-asparaqinate LCMS purity 96%, m/z 486/488 [M+H]⁺, ¹H NMR (400 MHz, CD₃OD) δ: 1.45-1.90 (8H, m, 4xCH₂), 2.30 (3H, s, CH₃), 3.10 (2H, m, CH₂), 3.25 (3H, s, CH₃), 4.25-4.40 (1 H, m, CH), 5.15-5.25 (1 H₁ m, CH), 7.60-7.75 (2H, m, Ar), 8.05 (1 H, s, Ar).

The carbamate used as starting material was prepared from Intermediate A and Intermediate D in a similar manner to the analgous starting material of Example 1. Example 3 Cyclopentyl Λ/-l5-r4-chloro-3-(methylsulfonvn^phenyll-4-rnethyl-1,3- thiazol-2-yl)-D-glutaminate

From . cyclopentyl Λ/²-(fe/f-butoxvcarbonv0-/V-{5-r4-chloro-3-(methylsulfonyl)phenvπ- 4-methyl-1.3-thiazol-2-yl)-D-αlutaminate. LCMS purity 95%, m/z 500 [M+H]⁺, ¹H NMR (300 MHz, CDCI₃) δ: 8.15 (1H, d, J=1.3 Hz), 7.54-7.51 (2H, m), 5.19-5.12 (1 H, m), 3.51-3.43 (1 H, m), 3.24 (3H, s), 2.72-2.49 (2H, m), 2.34 (3H, s), 2.24-2.08 (1 H, m), 1.93-1.74 (4H, m), 1.69-1.50 (6H, m), 1.22-1.18 (2H₁ m).

The carbamate used as starting material was prepared from Intermediate A and Intermediate E in a similar manner to the analgous starting material of Example 1

Example 4 Cvclopentyl Λ/MS-rø-chloro-S-fmethylsulfonvQphenylM-methyl-i .3- thiazol-2-vP-6-oxo-L-lysinate bistrifluoroacetate

From cyclopentyl Λ/²-[(benzyloxy)carbonyl]-Λ/⁶-{5-[4-chloro-3-(methylsulfonyl)phenyl]- 4-methyl-1 ,3-thiazol-2-yl}-6-oxo-L-lysinate (18mg, 0.027mmol) was treated with 35% HBr in AcOH (1.5ml) at RT for 1.5h. The solvent was then removed under high vacuum and the crude residue was purified by prep HPLC (MeCN / 0.05% TFA_aq) to afford the title compound (15mg, 74%). LCMS purity 90%, m/z 515 [M+H]⁺, ¹H NMR (300 MHz, CD₃OD) δ: 8.14 (1 H, d, J=1.9 Hz), 7.76-7.72 (2H, m), 5.35-5.28 (1 H, m), 4.06-4.00 (1 H, m), 3.35 (3H, s), 2.60 (2H, t, J=6.7 Hz), 2.40 (3H, s), 2.06-1.59 (12H, m).

The carbamate used in the above process was prepared by the following process;

To a solution of intermediate F (148mg, 0.49mmol) in DMF (10ml) were added EDC (142mg, 0.74mmol) and HOBt (100mg, 0.74mmol). A solution of Intermediate D (180mg, 0.49mmol) in DMF (3ml) was added, followed by Et₃N (138μl, 0.99mmol). The reaction mixture was stirred at RT for 48h. Water (50ml) was then added and the product extracted into EtOAc (2 x 50ml). The organic phase was washed with water (50ml) and brine (50ml) then dried (Na₂SO₄) and concentrated in vacuo. The crude residue was purified by flash chromatography eluting with EtOAc in heptane (10% to 70%) to afford a pale yellow solid (100mg, 31%)

Example 5 ΛM 5-r4-Chloro-3-(methylsulfonyl)phenvn-4-methyl-1 ,3-thiazol-2-yl>- L-glutamine

A solution of (S)-2-tert-Butoxycarbonylamino-4-[5-(4-chloro-3-methanesulfonyl- phenyl)-4-methyl-thiazol-2-ylcarbamoyl]-butyric acid (12mg, 0.0225mmol) in 20% TFA/ DCM (0.3ml) was allowed to stand at RT for 3h. After completion the reaction mixture was concentrated in vacuo to give the desired product (12mg, 100%). LCMS purity 94%, m/z 432/434 [M⁺+H], ¹H NMR (400 MHz, MeOD), δ: 2.10-2.25 (2 H, m, CH₂), 2.30 (3 H, s, CH₃), 2.65-2.75 (2 H, m, CH₂), 3.25 (3 H, s, CH₃), 3.95-4.05 (1 H, m, CH), 7.60-7.80 (2 H, m, Ar), 8.05 (1 H, s, Ar).

The acid used as starting material in the above process is prepared as follows: To a solution the starting material of Example 1 (20mg, 0.033mmol) in a mixture of THF (0.5ml) and MeOH (0.5ml) was added 2M aq NaOH (0.5ml). The mixture was allowed to stand at RT for 3h. Upon completion the reaction mixture was concentrated to near dryness, 1 M HCI added dropwise until pH 1-2. The resultant precipitate was collection by filtration under slight pressure. The solid was washed with water (0.5ml) and thoroughly dried in vacuo. Yield= 12mg, 68%. LCMS purity 94%, m/z 532/534 [M⁺+H], ¹H NMR (400 MHz, CDCI₃), δ: 1.55-1.70 (9 H, s, 3 x CH₃), 2.15-2.55 (2 H, m, CH₂), 2.60 (3 H, s, CH₃), 2.75-2.90 (2 H, m, CH₂), 3.55 (3 H, s, CH₃), 4.25-4.45 (1 H, m, CH), 7.85-8.00 (2 H, m, Ar), 8.35 (1 H, s, Ar).

Example 6 JV-(5-r4-Chloro-3-(methylsulfonyl)phenvπ-4-methyl-1.3-thiazol-2-yll- L-asparagine trifluoroacetate

From the compound of Example 2 using a similar methodology as described for the acid starting material of Example 5 . LCMS purity 98%, m/z 418/420 [M+H]⁺, ¹H NMR (400 MHz, CD₃OD) δ: 2.30 (3H, s, CH₃), 3.05-3.20 (2H, m, CH₂), 3.25 (3H, s, CH₃), 4.35 (1 H, m, CH), 7.60-7.75 (2H, m, Ar), 8.05 (1 H, s, Ar).

Example 7 Λ/⁶-! 5-r4-chloro-3-(methylsulfonyl)phenyl1-4-methyl-1 ,3-thiazol-2-yl>- 6-oxo-L-lysine

From the compound of Example 4 using a similar methodology as described for. the acid starting material of Example 5. LCMS purity 93%, m/z 446 [M+H]⁺. Example 8: ferf-Butyl ΛH5-r4-chloro-3-(methylsulfonvπphenvπ-4-methyl-1,3- thiazol-2-yl)-L-glutaminate

To a solution of tert-butyl (S)-2-tert-butoxycarbonylarnino-4-[5-(4-chloro-3- methanesulfonylphenyl)-4-methylthiazol-2-ylcarbamoyl]butyrate (50mg, 0.085 mmol) in EtOAc (0.25ml) was added 2M HCI/ ether solution (0.25ml) at RT. The reaction mixture was vigourously stirred for 4h. LCMS indicated 60% product and 30% SM. The reaction was retreated with a mixture of EtOAc (0.25ml) and 2M HCI/ ether (0.25ml). Stirring was continued for 1h. The resultant solid formed was collected by filtration under gravity, partitioned between EtOAc (3ml) and sat aq NaHCθ3 (0.5ml). EtOAc layer was washed with water (1ml), dried (Na₂SO₄), filtered and concentrated in vacuo to give the desired product (6.5mg, 16%). LCMS purity 95%, m/z 488/490 [M⁺+H], ¹H NMR (400 MHz, MeOD), δ: 1.35-1.40 (9 H, s, 3 x CH₃), 1.80-2.05 (2 H, m, CH₂), 2.30 (3 H, s, CH₃), 2.45-2.55 (2 H, m, CH₂), 3.25 (3 H, s, CH₃), 3.30-3.35 (1 H, m, CH), 7.60-7.70 (2 H, m, Ar), 8.05 (1 H, s, Ar).

The carbamate used in the above process was prepared from (4S)-5-tert-butoxy-4- [(tert-butoxycarbonyl)amino]-5-oxopentanoic acid and 5-(4-chloro-3-methane sulfonylphenyl)-4-methylthiazol-2-ylamine in a similar manner to the analogous starting material of Example 1.

LCMS purity 90%, m/z 558/590 [M+H] Example 9 Cvclopentyl ΛM5-r4-chloro-3-(methylsulfonvnphenyll-4-methyl-1.3- thiazol-2-yl>-/V²-cyclohexyl-L-qlutaminatθ

To a mixture of the compound of Example 1 (80mg, 0.13mmol) and K₂CO₃ (20mg, 0.14mmol) in THF (0.5ml) was added cyclohexanone (0.081 ml, 0.78mmol). AcOH glacial was added dropwise to adjust the pH of reaction to 5-6 and was stirred at RT for 1h before addition of NaCNBH₃ (16.4mg, 0.26mmol). Stirring was continued for 18h. The reaction mixture was concentrated in vacuo, diluted with EtOAc (10ml) and washed with sat aq NaHCO₃ (3ml) followed by water (3ml), dried (Na₂SO₄), filtered and concentrated in vacuo. Purification by preparative TLC (0.1% NH₄OH/ 0.9%MeOH/ 99% EtOAc, R_f= 0.4) gave the desired product (27mg, 36%). LCMS purity 83%, m/z 582/584 [M⁺+H], ¹H NMR (400 MHz, MeOD), δ: 1.00-1.90 (18 H, m, 9 x CH₂), 1.85-1.95 (2 H, m, CH₂), 2.30 (3 H, s, CH₃), 2.45-2.55 (2 H, m, CH₂), 3.25 (3 H, s, CH₃), 3.30-3.50 (2 H, m, 2 x CH), 5.05-5.15 (1 H, m, CH), 7.60-7.75 (2 H, m, Ar), 8.05 (1 H, s, Ar).

Examples 10 and 11 were prepared using the method described for Example 9.

Example 10 Cvclopentyl Λ/-{5-r4-chloro-3-(methylsulfonyl)phenyl1-4-methyl-1,3- thiazol-2-yl>-/V²-cvclohexyl-L-asparaginate

From the compound of Example 2 and cyclohexanone to give the title compound. LCMS purity 100%, m/z 568/570 [M+H]⁺, ¹H NMR (400 MHz, CD₃OD) δ: 1.40-2.15 (18H, m, 9xCH₂), 2.20-2.40 (2H, m, CH₂), 2.55 (3H, s, CH₃), 3.40 (1 H, m, CH), 3.50 (3H, s, CH₃), 4.75 (1 H, m, CH), 5.45 (1 H, m, CH), 7.85-7.95 (2H, m, Ar), 8.25 (1 H, s, Ar). Example 11 Cyclopentyl Λ/-(5-r4-chloro»3-(methylsulfonvnphenvn-4-methyl-1,3- thiazol-2-yl)-Λ/²-isobutyl-L-glutaminate

From the compound of Example 1 and isobutyraldehyde to give the title compound. LCMS purity 91 %, m/z 556 [M+H]⁺, ¹H NMR (300 MHz, CDCI₃) δ: 11.89 (1H, br s), 8.24 (1H, d, J=2.1 Hz), 7.62-7.59 (2H, m), 5.28-5.21 (1H, m), 3.32 (3H, s), 3.24 (1 H, dd, J=9.1 , 4.1 Hz), 2.80-2.57 (2H, m), 2.46-2.42 (2H, m), 2.41 (3H, s), 2.21-2.07 (1 H, m), 2.01-1.84 (4H, m), 1.78-1.56 (6H, m), 0.98 (6H, t, J=5.8 Hz).

Example 12 JV-f5-r4-Chloro-3-(methylsulfonyl)phenvπ-4-methyl-1,3-thiazol-2-yl)- N²-cvclohexyl-L-glutamine

To a solution of Example 9 (15mg, 0.025mmol) in a mixture of THF (0.3ml) and MeOH (0.3ml) was added 2M NaOH_aq (0.3ml). The mixture was allowed to stand at RT for 18h. Upon completion the reaction mixture was concentrated to near dryness, 1 M HCIaq was added dropwise until pH 1-2. The resultant precipitate was collected by filtration under slight pressure. The solid was washed with water (0.5ml) and thoroughly dried in vacuo (4.8mg, 35%). LCMS purity 95%, m/z 514/516 [M+H]⁺, ¹H NMR (400 MHz, CD₃OD) δ: 1.00-1.90 (8H, m, 4xCH₂), 1.90-2.20 (4H, m, 2xCH₂), 2.25 (3H, s, CH₃), 2.60 (2H, m, CH₂), 2.90-3.05 (1 H, m, CH), 3.20 (3H, s, CH₃), 3.75 (1 H, m, CH), 7.50-7.65 (2H, m, Ar), 8.00 (1 H, s, Ar).

Examples 13 and 14 were prepared by the method described for Example 12. Example 13 N-l5-r4-Chloro-3-(methvIsulfonyl)phenyl1-4-methyl-1.3-thiazol-2-ylV Λ^-cvclohexyl-L-asparaq i ne

From the compound of Example 10 to give the title compound. LCMS purity 99%, m/z 500/502 [M+H]⁺, ¹H NMR (400 MHz, CD₃OD) δ: 1.10-1.45 (6H, m, 3xCH₂), 1.55- 1.90 (4H, m, 2xCH₂), 2.00-2.20 (2H, m, CH₂), 2.30 (3H, s, CH₃), 3.00-3.15 (1 H, m, CH), 3.25 (3H, s, CH₃), 4.40 (1 H, m, CH), 7.70-7.80 (2H, m, Ar), 8.05 (1 H, s, Ar).

Example 14 Λ/-(5-r4-Chloro-3-(methylsulfonyl)phenvπ-4-methyl-1 ,3-thiazol-2-yl>- /V²-isobutyl-L-glutamine

From the compound of Example 11 to give the title compound. LCMS purity 100%, m/z 488 [M+H]⁺, ¹H NMR (300 MHz, CD₃OD) δ: 8.04 (1H, d, J=1.9 Hz), 7.68-7.57 (2H, m), 3.41-3.32 (1 H, m), 3.25 (3H, s), 2.71-2.63 (4H, m), 2.30 (3H, s), 2.14-2.00 (2H, m), 1.95-1.87 (1H, m), 0.95 (6H, d, J=6.6 Hz).

Example 15 Cvclopentyl Λ/²-acetyl-ΛK5-r4-chloro-3-(methylsulfonyl)phenvπ-4- methyl-1,3-thiazol-2-yl}-L-qlutaminate

To a solution of Example 1 (50mg, O.immol) in DCM (2ml) was added acetyl chloride (7μl, O.immol) at 0 ⁰C. The reaction mixture was stirred at RT for 36h and then the solvent was removed in vacuo. The resulting residue was purified by flash chromatography eluting with 2.5% MeOH in DCM to afford the title compound (33mg, 61%). LCMS purity 93%, m/z 542 [M+H]\ ¹H NMR (300 MHz, CDCI₃) δ: 11.11 (1 H, br s), 8.15 (1 H, d, J=1.3 Hz), 7.54-7.51 (2H, m), 6.42 (1 H, d, J=7.9 Hz), 5.19-5.12 (1 H, m), 4.60-4.51 (1 H, m), 3.24 (3H, s), 2.51 (2H, t, J=6.6 Hz), 2.34 (3H, s), 2.31-2.18 (1 H, m), 2.03 (3H, s), 1.93-1.85 (1 H, m), 1.85-1.73 (2H, m), 1.68-1.47 (6H, m).

Example 16 yV²-Acetyl-/V-{5-f4-chloro-3-(methylsulfonyl)phenvn-4-methyl-1 ,3- thiazoI-2-yl)-L-glutamine

From the compound of Example 17 using the method described for Example 12. LCMS purity 95%, m/z 474 [M+H]⁺, ¹H NMR (300 MHz, CD₃OD) δ: 8.16 (1 H, d, J=I .9 Hz), 7.76 (1 H, d, J=2.1 Hz), 7.74 (1 H, s), 4.33 (1 H, t, J=6.3 Hz), 3.36 (3H, s), 2.63- 2.51 (2H, m), 2.41 (3H, s), 2.37-2.19 (1 H, m), 2.13-2.03 (1 H, m), 2.00 (3H, s).

Example 17 Cyclopentyl Λ/⁵-(f5-r4-chloro-3-(methylsulfonyl)phenvπ-4-methyl- 1,3-thiazol-2-yl}carbamoyl)-L-omithinate

Crude cyclopentyl /V²-(te/t-butoxycarbonyl)-Λ/⁵-({5-[4-chloro-3-(methylsulfonyl) phenyl]-4-methyl-1 ,3-thiazol-2-yl}carbamoyl)-L-ornithinate was treated with 4M HCI in dioxane (5ml) at RT for 1.5h. The solvent was removed in vacuo and the residue purified by prep HPLC (MeCN / 0.05% TFA_aq) to give a clear oil (4mg, %). LCMS purity 100%, m/z 529/531 [M+Hf, ¹H NMR (300 MHz, CD₃OD) δ: 8.14 (1H, d, J=0.8 Hz), 7.80-7.67 (2H, m), 5.39-5.24 (1 H, m), 4.07 (1 H, t, J=6.4 Hz), 3.36 (3H, s), 2.39 (3H, s), 1.93 (1 H, m), 2.00-1.85 (5H, m), 1.81-1.62 (9H, m). The carbamate used as starting material in the above process was preapared as follows

To a suspension of Λ/-{5-[4-chloro-3-(methylsulfonyl)phenyl]-4-methyl-1 ,3-thiazol-2- yl}-1W-imidazole-1-carboxamide (80mg, 0.20mmol) and Intermediate G (61 mg, 0.20mmol) in DMF (3ml) was added Et₃N (57μl, 0.40mmol). The reaction was stirred at RT for 18h, after which time the solvent was removed in vacuo. The residue obtained was used directly without further purification, m/z 630/632 [M+H]⁺.

The imidazole carboxamide used in the above process was prepared as follows:

A suspension of Intermediate A (203mg, 0.67mmol) and DCI (160mg, 1mmol) in DCM (8ml) was heated at 40 ⁰C under a N₂ atmosphere for 3h. A precipitate had formed and was filtered and washed with DCM (10ml) to afford a white solid (240mg, 90%). ¹H NMR (300 MHz, CD₃OD) δ: 8.16 (1 H, s), 7.72-7.79 (3H, m), 7.09 (2H₁ s), 3.36 (3H, s), 2.39 (3H, s).

Example 18: Cvclopentyl O-f4-r(f5-f4-chloro-3-(methylsulfonyl)phenvπ-4- methyl-1,3-thiazol-2-yl>carbamoyl)amino1phenylVL-homoserinate

Crude cvclopentyl A/²-(te/Y-butoxycarbonvπ-0-(4-r((5-r4-chloro-3-(methylsulfonyl) phenvn-4-methvl-1.3-thiazol-2-yl)carbamovπaminolphenvl)-L-homoserinate was treated with 20% TFA in DCM (10ml) at RT for 1h. The solvent was then removed in vacuo and the resulting residue purified by prep HPLC (MeCN / water) to afford the title compoud as a clear oil (9mg). LCMS purity 90%, m/z 607/609 [M+H]⁺, ¹H NMR (300 MHz, CD₃OD) δ: 8.13 (1 H, d, J=U Hz), 7.78-7.73 (2H, m), 7.35 (2H, d, J=8.7 Hz), 6.77 (2H, d, J=8.9 Hz), 5.18 (1H₁ 1, J=5.7 Hz), 4.39 (2H, t, J=5.9 Hz), 4.18 (1H, t, J=5.5 Hz), 3.37 (3H, s), 2.53-2.46 (2H, m), 2.42 (3H, s), 1.95-1.85 (2H, m), 1.76-1.55 (6H, m).

The carbamate used in the above process was prepared as follows:

Crude 1 -{5-[4-chloro-3-(methylsulfonyl)phenyl]-4-methyl-1 ,3-thiazol-2-yl}-3-(4- hydroxyphenyl)urea was dissolved in anhydrous DMF (8ml) and treated with Intermediate H (200mg, 0.57mmol) and K₂CO₃ (158mg, 1.14mmol). The reaction was stirred at 40 ⁰C for 3h after which the solvent was removed in vacuo. The residue was redissolved in EtOAc (25ml) and washed with sat NaHCO_3(aq) (25ml) and brine (25ml). The organic was then dried (MgSO₄) and concentrated in vacuo. The resulting residue was used directly in the following stage without further purification, m/z 707 [M+H]⁺.

The urea used as starting material used in the above process was preapred as follows:

1-[4-(Benzyloxy)phenyl]-3-{5-[4-chloro-3-(methylsulfonyl)phenyl]-4-methyl-1 ,3-thiazol- 2-yl}urea (234mg, 0.44mmol) was treated with TFA (5ml) and thioanisole (500μl) at 80 ⁰C for 2h. The solvents were removed under high vacuum conditions and the resulting residue was used directly in the following stage without further purification, m/z 438 [M+H]⁺. The benzyl ether used in the above process was prepared as follows::

To a solution of the carbodiimide intermediate descibed in the previous example (226mg, 0.57mmol) in anhydrous DMF (9ml) was added 4-benzyloxyanaline (134mg, 0.57mmol) and Et₃N (159μl, 1.14mmol). The reaction was stirred under N₂ atmosphere at RT for 2h. The solvent was then removed in vacuo and the resulting residue purified by flash chromatography eluting with 3% MeOH in DCM to give the desired product (234mg, 78%). m/z 528 [M+H]⁺.

Example 19 Cvclopentyl Λ^-ffS-fΣ-acetamido-Φmethyl-I.S-thiazol-S-vD-Σ-chloro phenyllsulfonylV-L-ornithinate

Cvclopentyl Λ/²-(te/Y-butoxycarbonyl)-Λ/⁵-(|^'5-(2-acetamido-4-methyl-1₁3-thiazol-5-yl)-2- chloro phenylisulfonyll-L-ornithinate (27mg, 0.043mmol) was treated with 4M HCI in dioxane (3ml) and stirred at RT for 18h. The solvent was removed in vacuo and the residue washed with Et₂O. It was then purified by prep HPLC (MeCN / 0.05%TFA_aq) to afford the title compound (10mg, 44%). LCMS purity 98%, m/z 529/531 [M+H]⁺, ¹H NMR (300 MHz, CD₃OD) δ: 8.08 (1 H, t), 7.67 (2H, s), 3.97 (1 H, t, J=6.5 Hz), 3.00 (2H, t, J=6.6 Hz), 2.40 (3H, s), 2.23 (3H, s), 1.87 - 1.98 (4H, m), 1.55 - 1.78 (9H, m).

The thiazole used in the above process was prepared as follows:

Cyclopentyl /v⁵-{[5-(1-bromo-2-oxopropyl)-2-chlorophenyl]sulfonyl}-/V²-(terf- butoxycarbonyl)-L-ornithinate (50mg, O.Oδmmol) and acetylthiourea (10mg, O.Oδmmol) were dissolved in EtOH (5ml) and heated to 70 ⁰C for 1 h. The reaction was then cooled to RT and the solvent removed in vacuo. The residue was treated with water to induce precipitation. The precipitate was collected by filtration (27mg, 54%). ¹H NMR (300 MHz, CD₃OD) δ: 8.11 (1 H, s), 7.73 (2H, s), 4.00 (1 H, t, J=6.5 Hz), 3.00 (2H, t, J=6.5 Hz), 2.45 (3H, s), 2.31 (3H, s), 2.10 (4H, s), 1.64-2.06 (17H, m).

The α-bromoketone used in the above process was prepared by the following method:

Cyclopentyl Λ/²-(te/t-butoxycarbonyl)-Λ/⁵-{[2-chloro-5-(2-oxopropyl)phenyl] sulfonyl}-L- ornithinate (60mg, 0.11 mmol) was dissolved in dioxane (3ml) and bromine (4μl, O.Oδmmol) was added slowly. The reaction mixture was stirred at 25 ⁰C for 1h after which it was concentrated in vacuo. The residue was re-dissolved in EtOAc, washed with sat NaHCO_3(aq₎ then brine, then dried (MgSO₄) and concentrated in vacuo to afford the desired product as an orange oil (50mg, 75%). ¹H NMR (300 MHz, CDCI₃) δ: 8.03 (1 H, d, J=2.1 Hz), 7.55-7.62 (2H, m), 4.15 (1 H, dd, J=2.1 , 9.6 Hz), 3.58 (1 H, m), 2.91 (2H, q, J=7.6 Hz), 1.43-1.76 (15H, m), 1.37 (9H, s).

The ornithinate ester used in the above process was prepared as follows:

To a solution of Intermediate B (278mg, 1.04mmol) in dioxane (10ml) was added a solution of Na₂Cθ₃ (220mg, 2.07mmol) in water (2ml) followed by Intermediate G (311 mg, 1.04mmol). The reaction mixture was stirred at RT for 1.5h. The solvent was then removed in vacuo and the residue dissolved in EtOAc and washed with water, then dried (MgSO₄) and concentrated in vacuo. The residue was purified by flash chromatography eluting with 30% EtOAc in heptane (60mg, 11 %). m/z 554/556 [M+Na]⁺, ¹H NMR (300 MHz, CDCI₃) δ:7.91 (1H, d, J=2.2 Hz), 7.50 (1H, d, J=9.8 Hz), 7.35 (1 H, dd, J=2.2, 9.8 Hz), 4.14 (1 H, q, J=7.6 Hz), 3.80 (2H, s), 2.98 (2H, q, J=7.6 Hz), 1.59-1.85 (12H, m), 1.58 (3H, s), 1.45 (9H, s).

Example 20 Λ/⁵-! r5-(2-acetamido-4-methyl-1 ,3-thiazol-5-vO-2-chlorophenvπ sulfonyl)-L-ornithine

Example 22 was prepared from Example 21 using a similar methodology as described for Example 12. LCMS purity 100%, m/z 462 [M+H]\ ¹H NMR (300 MHz, CZ₆-DMSO) δ: 7.93 (1 H, s), 7.96 (2H, s), 4.01 (1 H, s), 2.86 (2H, br s), 2.37 (3H, s), 2.15 (3H, s), 1.55 (4H, br s).

Biological Results

(A) Broken Cell Carboxylesterase Assay

Any given compound of the present invention wherein Ri is an ester group may be tested to determine whether it meets the requirement that it be hydrolysed by intracellular esterases, by testing in the following assay.

Preparation of cell extract U937 or Hut78 tumour cells (~ 10⁹) were washed in 4 volumes of Dulbeccos PBS (~ 1 litre) and pelleted at 525 g for 10 min at 4^°C. This was repeated twice and the final cell pellet was resuspended in 35 ml of cold homogenising buffer (Trizma 10 mM, NaCI 130 mM, CaCI₂ 0.5 mM pH 7.0 at 25⁰C). Homogenates were prepared by nitrogen cavitation (700 psi for 50 min at 4⁰C). The homogenate was kept on ice and supplemented with a cocktail of inhibitors at final concentrations of:

Leupeptin 1 μM

Aprotinin 0.1 μM

E64 8 μM

Pepstatin 1.5 μM

Bestatin 162 μM

Chymostatin 33 μM

After clarification of the cell homogenate by centrifugation at 525 g for 10 min, the resulting supernatant was used as a source of esterase activity and was stored at - 8O⁰C until required.

Measurement of ester cleavage

Hydrolysis of esters to the corresponding carboxylic acids can be measured using the cell extract, prepared as above. To this effect cell extract (-30 μg / total assay volume of 0.5 ml) was incubated at 37⁰C in a Tris- HCI 25 mM, 125 mM NaCI buffer, pH 7.5 at 25⁰C. At zero time the ester (substrate) was then added at a final concentration of 2.5 μM and the samples were incubated at 37⁰C for the appropriate time (usually 0 or 80 min). Reactions were stopped by the addition of 3 x volumes of acetonitrile. For zero time samples the acetonitrile was added prior to the ester compound. After centrifugation at 12000 g for 5 min, samples were analysed for the ester and its corresponding carboxylic acid at room temperature by LCMS (Sciex API 3000, HP1100 binary pump, CTC PAL). Chromatography was based on an AceCN (75x2.1 mm) column and a mobile phase of 5-95 % acetonitrile in water /0.1 % formic acid.

Rates of hydrolysis are expressed in pg/mL/min.

Table 1 presents data showing that several amino acid ester motifs, conjugated to various intracellular enzyme inhibitors by several different linker chemistries are all hydrolysed by intracellular carboxyesterases to the corresponding acid. of

WO2006117548

9

(B) inhibition of PI3 Kinase v Activity Compounds of the Examples herein were tested in the following assay to determine their PI3 Kinase γ inhibitory activity (Upstate Ltd (Dundee, UK)):

In a final reaction volume of 20μl, PI3Kγ (human) is incubated in assay buffer containing 10μM phosphatidylinositol-4,5-bisphosphate and MgATP (concentration as required). The reaction is initiated by the addition of the MgATP mix. After incubation for 30 minutes at room temperature, the reaction is stopped by the addition of 5μl of stop solution containing EDTA and biotinylated phosphatidylinositol- 3,4,5-trisphosphate. Finally, 5μl of detection buffer is added, which contains europium-labelled anti-GST monoclonal antibody, GST-tagged GRP1 PH domain and streptavidin-allophycocyanin. The plate is then read in time-resolved fluorescence mode and the homogenous time-resolved fluorescence (HTRF) signal is determined according to the formula HTRF = 10000 x (Em665nm/Em620nm).

Duplicate data points are generated from a 1/3 log dilution series of a stock solution of compound in DMSO. Nine dilutions steps are made from a top concentration of 10μM, and a 'no compound' blank is included. The HTRF Pl 3-Kinase assay is performed at an ATP concentration at, or close to, the Km. HTRF ratio data is transformed into % activity of controls and analysed with a four parameter sigmoidal dose-response (variable slope) application. QC criteria is based on Top, Bottom, Hill slope, r² and IC₅₀, the concentration giving 50% inhibition, which is reported.

The results are reported in Table 2.

(C) Inhibition of PI3 Kinase α. β and δ Activity

Compounds of the Examples herein were tested in the following assay to determine their PI3 Kinase α,β and δ inhibitory activity ( Scottish Biomedical Ltd (Glasgow, UK)):

Compounds were tested against PI3 Kinase (p110α/p85α), PI3 Kinase (p110β/p85α), and PI3 Kinase (p110δ/p85α). IC₅₀ values were determined on an 8-point concentration curve with duplicate points at each concentration point. The concentration range was based on a 1 in 3 dilution of each compound with a starting concentration of 10μM.

The assay is based on AlphaScreen™ (Packard Bioscience, CT, USA) technology. The interaction of a donor bead coated with biotinylated -Pl(3,4 5) P3 with an acceptor bead coated with a PI(3,4,5)P3 binding protein brings acceptor and donor beads together, producing a cascade of chemical reactions and leading to the detected amplified luminescent signal. PI(3,4,5)P3 generated by the relevant PI3 kinase competes with biotinylated PI(3,4,5)P3 for interaction with the detector protein. In the absence of interaction, proximity of donor and acceptor beads is decreased, producing a loss of luminescent signal which is inversely related to enzyme activity.

The compound of Example 4 had IC50 values of 582, 2169 and 15nM against PI3 Kinase (p110α/p85α), PI3 Kinase (p110β/p85α), and PI3 Kinase (p110δ/p85α) respectively. The compound of Example 7 had IC50 values of 62, 943 and 582nM against PI3 Kinase (p110α/p85α), PI3 Kinase (p110β/p85α), and PI3 Kinase (p110δ/p85α).

(D) LPS-stimulation of THP-1 cells

Compounds of the Examples herein were tested in the following assay, to determine their effect on TNF-α release in LPS-stimulated cells - an effect mediated by, inter alia, the PI3 Kinase pathway.

THP-1 cells were plated in 100μl at a density of 4 x 10⁴ cells/well in V-bottomed 96 well tissue culture treated plates and incubated at 37 ⁰C in 5% CO₂ for16h. 2 Hours after the addition of the inhibitor in 100μl of tissue culture media, the cells were stimulated with LPS (E coli strain 005:B5, Sigma) at a final concentration of 1μg/ml and incubated at 37 ⁰C in 5% CO₂ for 6h. TNF-α levels were measured from cell-free supernatants by sandwich ELISA (R&D Systems #QTA00B)

The results are reported in Table 2.

(E) LPS-stimulation of human whole blood

Compounds of the Examples herein were tested in the following assay, to determine their effect on TNF-α release in LPS-stimulated whole blood cells - an effect mediated by, inter alia, the PI3 Kinase pathway.

Whole blood was taken by venous puncture using heparinised vacutainers (Becton Dickinson) and diluted in an equal volume of RPMI1640 tissue culture media (Sigma). 100μl was plated in V-bottomed 96 well tissue culture treated plates. 2 Hours after the addition of the inhibitor in 100μl of RPMH 640 media, the blood was stimulated with LPS (E coli strain 005: B5, Sigma) at a final concentration of 100ng/ml and incubated at 37 ⁰C in 5% CO₂ for 6h. TNF-α levels were measured from cell-free supematants by sandwich ELISA (R&D Systems #QTA00B)

The results are reported in Table 2.

Note: In each of the assays (B), (C) and (D), IC50 values were allocated to one of three ranges as follows and are shown in Table 2:

Range A: IC50 < 100OnM Range B: 100OnM < IC50 <10000nM Range C: IC50 >10000nM n/d: not determined

Table 2

(F) Accumulation of PI3 Kinase Inhibitor in Lung Tissue

Figure 1 shows the levels of the known PI3 kinase inhibitor compound (A) (disclosed in WO03072552)

compound A following intra-tracheal administration to mice. As can be seen the levels of compound in lung, plasma and spleen are all very similar indicating that although the agent was delivered to the lung there is still significant systemic exposure.

Figure 2 shows the levels of the acid of Example 7 above measured following intra- tracheal administration of the amino acid conjugate of Example 4 above. As can be seen the levels of the acid are significantly higher in lung tissue compared to plasma and spleen. Thus addition of the esterase motif has resulted in a compound that selectively concentrates in lung tissue. Levels of the ester Example 4 were low and only measurable in the lung at early time points indicating rapid cleavage by lung tissue.

Claims

Claims:

1. A compound of formula (I):

wherein: s is 0 or 1;

U is hydrogen or halogen;

X is -(C=O)-; an optionally substituted divalent phenylene, pyridinylene, pyrimidinylene, or pyrazinylene radical; or a bond;

P is optionally substituted CrC₆ alkyl and Z is -(CH₂)_Z-Y¹-L¹-R; or Z is optionally substituted C₁-C₆ alkyl and P is -(CH₂)_Z-Y¹-L¹-R;

Y¹ is a bond, -(C=O)-, -S(O₂)-, -C(=O)O-, -OC(=O)-, -(C=O)NR₃-,

-NR₃(C=O)-, -S(O₂)NR₃-, -NR₃S(O₂)-, or -NR₃(C=O)NR₅-, wherein R₃ and R₅ are independently hydrogen or optionally substituted (CrC₆)alkyl,

L¹ is a divalent radical of formula -(Alk¹)_m(Q)_n(Alk²)_p~ wherein m, n and p are independently O or 1 ,

Q is (i) an optionally substituted divalent mono- or bicyclic carbocyclic or heterocyclic radical having 5 - 13 ring members, or (ii), in the case where p is O, a divalent radical of formula -Q¹-X²- wherein X² is -0-, -S- or NR^A- wherein R^A is hydrogen or optionally substituted C₁-C₃ alkyl, and Q¹ is an optionally substituted divalent mono- or bicyclic carbocyclic or heterocyclic radical having 5 - 13 ring members, AIk¹ and AIk² independently represent optionally substituted divalent C₃-C₇ cycloalkyl radicals, or optionally substituted straight or branched, C₁-C₆ alkylene, C₂-C₆ alkenylene, or C₂-C₆ alkynylene radicals which may optionally contain or terminate in an ether (-O-), thioether (-S-) or amino (-NR^A-) link wherein R^A is hydrogen or optionally substituted C₁-C₃ alkyl;

z is 0 or 1 ;

R is a radical of formula (X) or (Y)

wherein

R₁ is a carboxylic acid group (-COOH), or an ester group which is hydrolysable by one or more intracellular carboxylesterase enzymes to a carboxylic acid group; and

R₄ is hydrogen; or optionally substituted C₁-C₆ alkyl, C₃-C₇ cycloalkyl, aryl or heteroaryl Or -(C=O)R₃, -(C=O)OR₃, or -(C=O)NR₃ wherein R₃ is hydrogen or optionally substituted (C_rC₆)alkyl.

2. A compound as claimed in claim 1 which has formula (II):

wherein U, P, X, Z and s are as defined in claim 1.

3. A compound as claimed in claim 1 or claim 2 wherein U is chloro.

4. A compound as claimed in any of the preceding claims wherein P is methyl.

5. A compound as claimed in any of the preceding claims wherein X is -(C=O)-.

6. A compound as claimed in any of the preceding claims wherein z is 0.

7. A compound as claimed in any of the preceding claims wherein Y¹ is -NR₃-, -S-, -O-, -C(=O)NR₃-, -NR₃C(=O)-, or -C(=O)O-, wherein R₃ is hydrogen or optionally substituted Ci-C₆ alkyl.

8. A compound as claimed in any of claims 1 to 6 wherein Y¹ is a bond.

9. A compound as claimed in claim 1 having formula (II):

wherein L¹ and R are as defined in claim 1.

10. A compound as claimed in any of the preceding claims wherein, in the radical L¹, AIk¹ and AIk², when present, are selected from -CH₂-, -CH₂CH₂-, -CH₂CH₂CH₂-, and divalent cyclopropyl, cyclopentyl and cyclohexyl radicals.

11. A compound as claimed in any of the preceding claims wherein, in the radical L¹, Q is a divalent phenyl radical or a mono-, or bi-cyclic heteroaryl radical having 5 to 13 ring members,

12. A compound as claimed in claim 10 wherein Q is 1 ,4-phenylene.

13. A compound as claimed in any of the preceding claims wherein, in the radical L¹, m and p are 0.

14. A compound as claimed in any of claims 1 to 12 wherein, in the radical L¹, n and p are 0 and m is 1.

15. A compound as claimed in any of claims 1 to 12 wherein, in the radical L¹, m, n and p are all 0.

16. A compound as claimed in claim 9 wherein L₁ is -CH₂-, -CH₂CH₂- or -CH₂CH₂CH₂-

17. A compound as claimed in any of claims 1 to 8 wherein the radical -L¹-Y¹-[CH₂],- is selected from -(CH₂)₃NH-, -CH₂C(=O)NH-, -CH₂CH₂C(=O)NH-, -CH₂C(O)O-, -CH₂S-, -CH₂CH₂C(O)O-, -(CH₂J₄NH-, -CH₂CH₂S-, -CH₂O, -CH₂CH₂O-,

18. A compound as claimed in any of claims 1 to 8 wherein the radical -L¹-Y¹-[CH₂]_Z- is -CH₂-.

19. A compound as claimed in any of the preceding claims wherein Ri is an ester group of formula -(C=O)OR₇ wherein R₇ is R₈RgRi₀C- wherein

(i) R₈ is hydrogen or optionally substituted (Ci-C₃)alkyl-(Z¹)_a-[(Cr C₃)alkyl]_b- or (C₂-C₃)alkenyl-(Z¹)_a-[(CrC₃)alkyl]b- wherein a and b are independently O or 1 and Z¹ is -0-, -S-, or -NRn- wherein Rn is hydrogen or (C_rC₃)alkyl; and R₉ and R₁₀ are independently hydrogen or (C_rC₃)alkyl-;

(ii) R₈ is hydrogen or optionally substituted R₁₂Ri₃N-(C_rC₃)alkyl- wherein Ri2 is hydrogen or (C_rC₃)alkyl and Ri₃ is hydrogen or (C_rC₃)alkyl; or R₁₂ and Ri₃ together with the nitrogen to which they are attached form an optionally substituted monocyclic heterocyclic ring of 5- or 6- ring atoms or bicyclic heterocyclic ring system of 8 to 10 ring atoms, and R₉ and R_i0 are independently hydrogen or (C_rC₃)alkyl-;or

(iii) R₈ and Rg taken together with the carbon to which they are attached form an optionally substituted monocyclic carbocyclic ring of from 3 to 7 ring atoms or bicyclic carbocyclic ring system of 8 to 10 ring atoms, and R₁₀ is hydrogen.

20. A compound as claimed in claim 19 wherein Ri₀ is hydrogen.

21. A compound as claimed in claim 19 or claim 20 wherein R₇ is methyl, ethyl, n- or iso-propyl, n-, sec-, or tert-butyl, cyclohexyl, allyl, phenyl, benzyl, 2-, 3- or 4- pyridylmethyl, N-methylpiperidin-4-yl, tetrahydrofuran-3-yl or methoxyethyl.

22. A compound as claimed in claim 19 or claim 20 wherein R₇ is cyclopentyl.

23. A compound as claimed in any of the preceding claims wherein R is a group of formula (X).

24. A compound as claimed in claim 23 wherein R₄ is optionally substituted C₁-C₆ alkyl, C₃-C₇cycloalkyl, aryl or heteroaryl.

25. A compound as claimed in claim 23 wherein R₄ is methyl, ethyl, n-or isopropyl, cyclopropyl, cyclopentyl, cyclohexyl, phenyl, or pyridyl.

26. A compound as claimed in claim 23 wherein R₄ is hydrogen, -(C=O)R₃, - (C=O)OR₃, or -(C=O)NR₃ wherein R₃ is hydrogen or optionally substituted (C₁- C₆)alkyl

27. A compound as claimed in any of claims 1 to 22 wherein R is a group of formula (Y)

28. A compound as claimed in claim 27 wherein ring or ring system D is selected from the following:

29. A compound as claimed in claim 1 having the structure of any of the compounds of the specific Examples herein.

30. A compound as claimed in claim 1 selected from the group consisting of cyclopentyl /V²-(te/t-butoxycarbonyl)-Λ/-{5-[4-chloro-3-(methyl sulfonyl)phenyl]-4- methyl-1 ,3-thiazol-2-yl}-L-glutaminate and cyclopentyl Λ/⁶-{5-[4-chloro-3-(methylsulfonyl)phenyl]-4-methyl-1 ,3-thiazol-2-yl}-6-oxo- L-lysinate

31. A pharmaceutical composition comprising a compound as claimed in any of the preceding claims, together with a pharmaceutically acceptable carrier.

32. The use of a compound as claimed in any of claims 1 to 30 in the preparation of a composition for inhibiting the activity of a PI3 kinase enzyme.

33. The use as claimed in claim 32 for the inhibition of PI3 kinase c$ and/or PI3 kinase γ activity, ex vivo or in vivo.

34. A method of inhibiting the activity of a PI3 kinase enzyme comprising contacting the enzyme with an amount of a compound as claimed in any of claims 1 to 30 effective for such inhibition.

35. A method as claimed in claim 34 for the inhibition of PI3 kinase o; and/or PI3 kinase γ activity, ex vivo or in vivo.

36. The use as claimed in claim 32 or claim 33, or a method as claimed in claim 33 or claim 34, for the treatment of neoplastic, immune or inflammatory disease, which comprises administering to a subject suffering such disease an effective amount of a compound as claimed in any of claims 1 to 30.

37. The use or method as claimed in claim 36 for the treatment of cancer cell proliferation.

38. The use or method as claimed in claim 36 for the treatment of cancers, including bowel cancer, ovarian cancer, head and neck and cervical squamous cancers, gastric and lung cancers, anaplastic oligodendrogliomas, glioblastoma multiforme or medulloblastomas.

39. The use or method as claimed in claim 36 for the treatment of rheumatoid arthritis, psoriasis, inflammatory bowel disease, Crohn's disease, ulcerative colitis, chronic obstructive pulmonary disease, asthma, multiple sclerosis, diabetes, atopic dermatitis, graft versus host disease, or systemic lupus erythematosus, systemic lupus erythematosus, myocardial ischemia, or reperfusion injury.

40. A method for the selective inhibition of the activity of a PI3 kinase enzyme enzyme in macrophages and/or monocytes relative to other cell types, comprising contacting the enzyme with an amount, effective for such inhibition, of a compound as claimed in any of claims 1 to 26.

37. A pharmaceutical composition as claimed in claim 31 which is adapted for topical administration and wherein, in the compound as claimed in any of claims 1 to 30, R is linked to the carbon atom to which it is attached through a methylene radical -CH₂-.