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Title:
1,3-DIMETHYLBENZIMIDAZOLONE DERIVATIVE AS AN INHIBITOR OF THE BRPF1 BROMODOMAIN
Document Type and Number:
WIPO Patent Application WO/2016/062737
Kind Code:
A1
Abstract:
A novel benzoimidazolyl compound, pharmaceutical compositions containing such a compound and its use in therapy.

Inventors:
BAMBOROUGH PAUL (GB)
CHUNG CHUN-WA (GB)
LE GALL ARMELLE (GB)
SHEPPARD ROBERT JOHN (GB)
Application Number:
PCT/EP2015/074298
Publication Date:
April 28, 2016
Filing Date:
October 21, 2015
Export Citation:
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Assignee:
GLAXOSMITHKLINE IP NO 2 LTD (GB)
International Classes:
C07D403/04; A61K31/496; A61P25/00; A61P35/00; A61P37/00
Other References:
DEMON, E. H. ET AL., ACS MEDICINAL CHEMISTRY LETTERS, vol. 5, 10 September 2014 (2014-09-10), pages 1190 - 1195, XP002750623
Attorney, Agent or Firm:
SHORE, Andrew, David (Global Patents 980 Great West Road,Brentford, Middlesex TW8 9GS, GB)
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Claims:
CLAIMS

1. A compound of formula (I) which is N-(1 ,3-dimethyl-6-(2-methylpiperazin-1 -yl)-2-oxo- 2,3-dihydro-1 H-benzo[d]imidazol-5-yl)-2-methoxybenzamide

or a salt thereof. 2. A compound of formula (IA) which is (R)-N-(1 ,3-dimethyl-6-(2-methylpiperazin-1-yl)-2- oxo-2,3-dihydro-1 H-benzo[d]imidazol-5-yl)-2-methoxybenzamide

or a salt thereof.

3. A compound of formula (IB) which is (S)-N-(1 ,3-dimethyl-6-(2-methylpiperazin-1-yl)-2- oxo-2,3-dihydro-1 H-benzo[d]imidazol-5-yl)-2-methoxybenzamide

or a salt thereof.

4. A compound according to any one of claims 1 to 3 or a pharmaceutically acceptable salt thereof.

5. A pharmaceutical composition which comprises a compound or a pharmaceutically acceptable salt thereof as defined in claim 4 and one or more pharmaceutically acceptable excipient(s).

6. A combination comprising a compound or a pharmaceutically acceptable salt thereof as defined in claim 4 together with one or more other therapeutically active agents.

7. A compound or a pharmaceutically acceptable salt thereof as defined in claim 4 for use in therapy.

8. A compound or a pharmaceutically acceptable salt thereof as defined in claim 4 for use in the treatment of diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated.

9. A compound for use according to claim 8, wherein the disease or condition is a chronic autoimmune condition.

10. A compound for use according to claim 8, wherein the disease or condition is an inflammatory condition.

1 1. A compound for use according to claim 8, wherein the disease or condition is cancer.

12. Use of a compound or a pharmaceutically acceptable salt thereof as defined in claim 4 in the manufacture of a medicament for the treatment of diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated. 13. A method of treatment of diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated in a subject in need thereof which comprises administering a

therapeutically effective amount of a compound or a pharmaceutically acceptable salt thereof as defined in claim 4. 14. A method of treatment according to claim 13, wherein the disease or condition is a chronic autoimmune condition.

15. A method of treatment according to claim 13, wherein the disease or condition is an inflammatory condition.

16. A method of treatment according to claim 13, wherein the disease or condition is cancer.

17. A method of treatment according to any one of claims 13 to 16 in which the subject a human.

Description:
1 ,3-DIMETHYLBENZIMIDAZOLONE DERIVATIVE AS AN INHIBITOR OF THE

BRPF1 BROMODOMAIN

Field of the Invention

The present invention relates to a novel compound, pharmaceutical compositions containing such a compound and to its use in therapy.

Background of the Invention

The genomes of eukaryotic organisms are highly organised within the nucleus of the cell. The long strands of duplex DNA are wrapped around an octomer of histone proteins (most usually comprising two copies of histones H2A, H2B, H3 and H4) to form a

nucleosome. This basic unit is then further compressed by the aggregation and folding of nucleosomes to form a highly condensed chromatin structure. A range of different states of condensation are possible, and the tightness of this structure varies during the cell cycle, being most compact during the process of cell division. Chromatin structure plays a critical role in regulating gene transcription, which cannot occur efficiently from highly condensed chromatin. The chromatin structure is controlled by a series of post-translational

modifications to histone proteins, notably histones H3 and H4, and most commonly within the histone tails which extend beyond the core nucleosome structure. These modifications include acetylation, methylation, phosphorylation, ubiquitinylation, SUMOylation and numerous others. These epigenetic marks are written and erased by specific enzymes, which place the tags on specific residues within the histone tail, thereby forming an epigenetic code, which is then interpreted by the cell to allow gene specific regulation of chromatin structure and thereby transcription.

Histone acetylation is usually associated with the activation of gene transcription, as the modification loosens the interaction of the DNA and the histone octomer by changing the electrostatics. In addition to this physical change, specific proteins bind to acetylated lysine residues within histones to read the epigenetic code. Bromodomains are small (=1 10 amino acid) distinct domains within proteins that bind to acetylated lysine residues commonly but not exclusively in the context of histones. There is a family of around 50 proteins known to contain bromodomains, and they have a range of functions within the cell.

BRPF1 (also known as peregrin or Protein Br140) is a bromodomain-containing protein that has been shown to bind to acetylated lysine residues in histone tails, including H2AK5ac, H4K12ac and H3K14ac (Poplawski et al, J. Mol. Biol., 2014 426: 1661-1676). BRPF1 also contains several other domains typically found in chromatin-associated factors, including a double plant homeodomain (PHD) and zinc finger (ZnF) assembly (PZP), and a chromo/Tudor-related Pro-Trp-Trp-Pro (PWWP) domain. BRPF1 forms a tetrameric complex with monocytic leukemia zinc-finger protein (MOZ, also known as KAT6A or MYST3) inhibitor of growth 5 (ING5) and homolog of Esa1 -associated factor (hEAF6). In humans, the t(8;16)(p1 1 ;p13) translocation of MOZ (monocytic leukemia zinc-finger protein, also known as KAT6A or MYST3) is associated with a subtype of acute myeloid leukemia and

contributes to the progression of this disease (Borrow et al, Nat. Genet., 1996 14: 33-41 ). The BRPF1 bromodomain contributes to recruiting the MOZ complex to distinct sites of active chromatin and hence is considered to play a role in the function of MOZ in regulating transcription, hematopoiesis, leukemogenesis, and other developmental processes (Ullah et al, Mol. Cell. Biol., 2008 28: 6828-6843; Perez-Campo et al, Blood, 2009 1 13: 4866-4874). Demont et al, ACS Med. Chem. Lett., (2014) (dx.doi.org/10.1021/ml5002932), discloses certain 1 ,3-dimethyl benzimidazolones as potent, selective inhibitors of the BRPF1 bromodomain.

Summary of the Invention

The compound of the invention is an inhibitor of BRPF1 bromodomain and has an improved profile with respect to known inhibitors of BRPF1 , for example in a certain aspect improved solubility and, in another aspect has been shown to possess an improved profile with respect to known inhibitors of BRPF1 , for example potency, and improved selectivity for BRPF1 over other bromodomains for example BRPF2 and BRPF3, BRD9, and the BET family of bromodomain-containing proteins.

In a first aspect of the invention, there is provided a compound of formula (I)

or a salt thereof.

In a further aspect of the invention, there is provided a compound of formula (I) or a pharmaceuticallyacceptable salt- thereof. In a further aspect of the invention, there is provided a pharmaceutical composition comprising a compound of formula (I), or a pharmaceutically-acceptable salt thereof, and one or more pharmaceutically-acceptable excipient(s). In a further aspect of the invention, there is provided a compound of formula (I), or a pharmaceutically-acceptable salt thereof, for use in therapy. In a further aspect of the invention, there is provided a compound of formula (I), or a pharmaceutically-acceptable salt thereof, for the treatment of diseases or conditions for which a bromodomain inhibitor, for example a BRPF1 bromodomain inhibitor, is indicated. In a further aspect of the invention, there is provided a method of treating diseases or conditions for which a bromodomain inhibitor, for example a BRPF1 bromodomain inhibitor, is indicated in a subject in need thereof which comprises administering a therapeutically-effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof. In a further aspect of the invention, there is provided the use of a compound of formula (I), or a pharmaceutically-acceptable salt thereof, in the manufacture of a medicament for the treatment of diseases or conditions for which a bromodomain inhibitor, for example a BRPF1 inhibitor, is indicated. Detailed Description of the Invention

The invention relates to a compound of formula (I) which is N-(1 ,3-dimethyl-6-(2- methylpiperazin-1 -yl)-2-oxo-2,3-dihydro-1 H-benzo[d]imidazol-5-yl)-2-methoxybenzamide

or a salt thereof.

The compound of formula (I) contains a chiral atom and hence may exist in one or more stereoisomeric forms. The present invention encompasses each of the stereoisomers of the compound of formula (I), whether as individual stereoisomers or as mixtures thereof including racemic mixtures. Either stereoisomer may contain less than 10% by weight, for example less than 5% by weight, less than 0.5% by weight, or less than 0.1 % by weight of the other stereoisomer. Separation of enantiomers, may be achieved by conventional techniques known to those skilled in the art, e.g. by fractional crystallisation or chiral chromatography, for example chiral HPLC.

In one embodiment there is provided a compound of formula (IA) which is (R)-N-(1 ,3- dimethyl-6-(2-methylpiperazin-1 -yl)-2-oxo-2,3-dihydro-1 H-benzo[d]imidazol-5-yl)-2- methoxybenzamide

or a salt thereof.

In a further embodiment there is provided a compound of formula (IB) which is (S) (1 ,3-dimethyl-6-(2-methylpiperazin-1 -yl)-2-oxo-2,3-dihydro-1 H-benzo[d]imidazol-5-yl)-2- methoxybenzamide

or a salt thereof.

Certain of the compounds of the invention may exist in tautomeric forms. It will be understood that the present invention encompasses all of the tautomers of the compounds of the invention whether as individual tautomers or as mixtures thereof.

It will be appreciated that the compounds of formula (IA) and formula (IB) are within the scope of the compound of formula (I). As used herein, unless otherwise stated, a reference to a compound of formula (I) also includes a reference the compound of formula (IA) and the compound of formula (IB).

It will be appreciated that the present invention covers the compound of formula (I) as the free base and as salts thereof, for example as a pharmaceutically-acceptable salt. In one embodiment the invention relates to the compound of formula (I) in the form of a salt. In another embodiment the invention relates to the compound of formula (I) in the form of a free base. In a further embodiment the invention relates to the compound of formula (I) in the form of a pharmaceutically-acceptable salt.

Suitable pharmaceutically acceptable salts can include acid addition salts. For a review of suitable pharmaceutically acceptable salts see Berge et al., J. Pharm. Sci., 66:1- 19, (1977). Typically, a pharmaceutically-acceptable salt may be readily prepared by using a desired acid or base as appropriate. The resultant salt may precipitate from solution and be collected by filtration or may be recovered by evaporation of the solvent.

A pharmaceutically acceptable acid addition salt can be formed by reaction of a compound of formula (I) with a suitable inorganic or organic acid (such as hydrobromic, hydrochloric, sulphuric, nitric, phosphoric, succinic, maleic, acetic, propionic, fumaric, citric, tartaric, lactic, benzoic, salicylic, glutamaic, aspartic, p-toluenesulfonic, benzenesulfonic, methanesulfonic, ethanesulfonic, naphthalenesulfonic such as 2-naphthalenesulfonic, or hexanoic acid), optionally in a suitable solvent such as an organic solvent, to give the salt which is usually isolated for example by crystallisation and filtration or by evaporation followed by trituration. A pharmaceutically acceptable acid addition salt of a compound of formula (I) can comprise or be for example a hydrobromide, hydrochloride, sulfate, nitrate, phosphate, succinate, maleate, acetate, propionate, fumarate, citrate, tartrate, lactate, benzoate, salicylate, glutamate, aspartate, p-toluenesulfonate, benzenesulfonate, methanesulfonate, ethanesulfonate, naphthalenesulfonate (e.g. 2-naphthalenesulfonate) or hexanoate salt. In one embodiment a pharmaceutically acceptable acid addition salt of a compound of formula (I) can comprise or be a hydrochloride, sulfate, maleate, fumarate, citrate, p-toluenesulfonate, benzenesulfonate or methanesulfonate salt.

Other non-pharmaceutically acceptable salts, e.g. formates, oxalates and

trifluoroacetates, may be used, for example in the isolation of the compound of formula (I), and are included within the scope of this invention.

The invention includes within its scope all possible stoichiometric and non- stoichiometric forms of the salts of the compound of formula (I).

It will be appreciated that many organic compounds can form complexes with solvents in which they are reacted or from which they are precipitated or crystallized. These complexes are known as "solvates". For example, a complex with water is known as a "hydrate". Solvents with high boiling points and/or capable of forming hydrogen bonds such as water, xylene, /V-methyl pyrrolidinone, methanol and ethanol may be used to form solvates. Methods for identification of solvates include, but are not limited to, NMR and microanalysis. Solvates, when formed, may be stoichiometric or non-stoichiometric.

The invention encompasses all prodrugs, of the compound of formula (I) or a pharmaceutically acceptable salt thereof, which upon administration to the recipient is capable of providing (directly or indirectly) the compound of formula (I) or a pharmaceutically acceptable salt thereof, or an active metabolite or residue thereof. Such derivatives are recognizable to those skilled in the art, without undue experimentation. Reference is made to the teaching of Burger's Medicinal Chemistry and Drug Discovery, 5 th Edition, Vol 1 : Principles and Practice, which is incorporated herein by reference to the extent of teaching such derivatives.

The compound of formula (I) may be in crystalline or amorphous form. Furthermore, some of the crystalline forms of the compound of formula (I) may exist as polymorphs, which are included within the scope of the present invention. Polymorphic forms of the compound of formula (I) may be characterized and differentiated using a number of conventional analytical techniques, including, but not limited to, X-ray powder diffraction (XRPD) patterns, infrared (IR) spectra, Raman spectra, differential scanning calorimetry (DSC),

thermogravimetric analysis (TGA) and solid state nuclear magnetic resonance (SSNMR).

It will be appreciated from the foregoing that included within the scope of the invention are solvates, isomers and polymorphic forms of the compound of formula (I) and salts thereof.

The compound of formula (I) or salts thereof may be made by a variety of methods. Illustrative general synthetic methods are set out below.

The compound of formula (I) may be prepared by deprotection of the compound of formula (II)

by, for example, treating the compound of formula (II) with a suitable acid, for example trifluoroacetic acid, in a suitable solvent, for example dichloromethane, at a suitable temperature, for example ambient temperature.

The compound of formula (II) may be prepared by reacting the compound of formula (III) with 2-methoxybenzoyl chloride in a suitable solvent, for example dichloromethane, in the presence of a suitable base, for example pyridine, at a suitable temperature, for example ambient temperature.

The compound of formula (III) can be prepared by reduction of the compound of formula (IV), for example by hydrogenation of a solution of the compound of formula (IV) in suitable solvent, for example /so-propyl alcohol, in the presence of a suitable catalyst, for example palladium supported on carbon, at a suitable temperature, for example ambient temperature.

The compound of formula (IV) may be prepared by reaction of a compound of formula (V) with the compound of formula (VI) in a suitable solvent, for example

dimethylsulfoxide (DMSO) at a suitable temperature for example 100-150°C under microwave irradiation, in the presence of a suitable base, for example N,N- diisopropylethylamine.

The compound of formula (V) may be prepared by nitration of the compound of formula (VII) by, for example, the addition of nitric acid to a solution of a compound of formula (VII) in a suitable solvent, for example acetic anhydride, at a suitable temperature, for example between -30°C and 0°C.

The compound of formula (VII) may be prepared by dimethylation of the compound of formula (VIII) by, for example treatment of a solution of the compound of formula (VIII) in a suitable solvent, for example Ν,Ν-dimethylformamide (DMF), with excess iodomethane in the presence of a suitable base, for example sodium hydride, at a suitable temperature, for example 0°C to ambient temperature.

The compound of formula (VIII) may be prepared from the compound of formula (IX) by treatment with di(1 /-/-imidazol-1-yl)methanone in a suitable solvent, for example tetrahydrofuran (THF), at a suitable temperature, for example between 0°C and 5°C

Where the compound of formula (I) is a mixture of isomers, the compounds of formula (IA) and formula (IB) can be obtained from the compound of formula (I) using suitable separation techniques which are familiar to those skilled in the art, such as those described herein. Alternatively the compounds of formula (IA) and (IB) may be prepared by a chiral synthesis procedure. By way of illustration, the compound of formula (IA) may be prepared by the procedure set out in Scheme 1 .

Scheme 1

It will be appreciated by those skilled in the art that it may be advantageous to protect one or more functional groups of the compounds described above. Examples of protecting groups and the means for their removal can be found in T. W. Greene 'Protective Groups in Organic Synthesis' (4th edition, J. Wiley and Sons, 2006). Suitable amine protecting groups include acyl (e.g. acetyl), carbamate (e.g. 2',2',2'-trichloroethoxycarbonyl, benzyloxycarbonyl or t-butoxycarbonyl) and arylalkyl (e.g. benzyl), which may be removed by hydrolysis (e.g. using an acid such as hydrochloric acid in dioxane or trifluoroacetic acid in dichloromethane) or reductively (e.g. hydrogenolysis of a benzyl or benzyloxycarbonyl group or reductive removal of a 2',2',2'-trichloroethoxycarbonyl group using zinc in acetic acid) as appropriate. Other suitable amine protecting groups include trifluoroacetyl (-COCF 3 ) which may be removed by base catalysed hydrolysis.

It will be appreciated that in any of the routes described above, the precise order of the synthetic steps by which the various groups and moieties are introduced into the molecule may be varied. It will be within the skill of the practitioner in the art to ensure that groups or moieties introduced at one stage of the process will not be affected by subsequent transformations and reactions, and to select the order of synthetic steps accordingly.

Compounds of formula (VI) and di(1 /-/-imidazol-1 -yl)methanone are either known in the literature or are commercially available, for example from Sigma-Aldrich, UK, or may be prepared by analogy with known procedures, for example those disclosed in standard reference texts of synthetic methodology such as J. March, Advanced Organic Chemistry, 6th Edition (2007), WileyBlackwell, or Comprehensive Organic Synthesis (Trost B.M. and Fleming I., (Eds.), Pergamon Press, 1991), each incorporated herein by reference as it relates to such procedures.

The compound of formula (I) and salts thereof, in particular pharmaceutically- acceptable salts thereof, are BRPF1 bromodomain inhibitors, and thus are believed to have potential utility in the treatment of diseases or conditions for which a bromodomain inhibitor is indicated. Bromodomain inhibitors are believed to be useful in the treatment of a variety of diseases or conditions related to systemic or tissue inflammation, inflammatory responses to infection or hypoxia, cellular activation and proliferation, lipid metabolism, fibrosis and in the prevention and treatment of viral infections. Bromodomain inhibitors may be useful in the treatment of a wide variety of chronic autoimmune and inflammatory conditions such as rheumatoid arthritis, osteoarthritis, psoriasis, systemic lupus erythematosus, multiple sclerosis, inflammatory bowel disease (Crohn's disease and ulcerative colitis), asthma, chronic obstructive airways disease, pneumonitis, myocarditis, pericarditis, myositis, eczema, dermatitis (including atopic dermatitis), alopecia, vitiligo, bullous skin diseases, nephritis, vasculitis, atherosclerosis, Alzheimer's disease, depression, Sjogren's syndrome, sialoadenitis, central retinal vein occlusion, branched retinal vein occlusion, Irvine-Gass syndrome (post-cataract and post-surgical), retinitis pigmentosa, pars planitis, birdshot retinochoroidopathy, epiretinal membrane, cystic macular edema, parafoveal telengiectasis, tractional maculopathies, vitreomacular traction syndromes, retinal detachment,

neuroretinitis, idiopathic macular edema, retinitis, dry eye (kerartoconjunctivitis Sicca), vernal keratoconjunctivitis, atopic keratoconjunctivitis, uveitis (such as anterior uveitis, pan uveitis, posterior uveits, uveitis-associated macula edema), scleritis, diabetic retinopathy, diabetic macula edema, age-related macula dystrophy, hepatitis, pancreatitis, primary biliary cirrhosis, sclerosing cholangitis, Addison's disease, hypophysitis, thyroiditis, type I diabetes, type 2 diabetes and acute rejection of transplanted organs. Bromodomain inhibitors may be useful in the treatment of a wide variety of acute inflammatory conditions such as acute gout, nephritis including lupus nephritis, vasculitis with organ involvement such as

glomerulonephritis, vasculitis including giant cell arteritis, Wegener's granulomatosis, Polyarteritis nodosa, Behcet's disease, Kawasaki disease, Takayasu's Arteritis, pyoderma gangrenosum, vasculitis with organ involvement and acute rejection of transplanted organs. Bromodomain inhibitors may be useful in the treatment of diseases or conditions which involve inflammatory responses to infections with bacteria, viruses, fungi, parasites or their toxins, such as sepsis, sepsis syndrome, septic shock, endotoxaemia, systemic inflammatory response syndrome (SIRS), multi-organ dysfunction syndrome, toxic shock syndrome, acute lung injury, ARDS (adult respiratory distress syndrome), acute renal failure, fulminant hepatitis, burns, acute pancreatitis, post-surgical syndromes, sarcoidosis, Herxheimer reactions, encephalitis, myelitis, meningitis, malaria and SIRS associated with viral infections such as influenza, herpes zoster, herpes simplex and coronavirus. Bromodomain inhibitors may be useful in the treatment of conditions associated with ischaemia-reperfusion injury such as myocardial infarction, cerebro-vascular ischaemia (stroke), acute coronary syndromes, renal reperfusion injury, organ transplantation, coronary artery bypass grafting, cardio-pulmonary bypass procedures, pulmonary, renal, hepatic, gastro-intestinal or peripheral limb embolism. Bromodomain inhibitors may be useful in the treatment of disorders of lipid metabolism via the regulation of APO-A1 such as hypercholesterolemia, atherosclerosis and Alzheimer's disease. Bromodomain inhibitors may be useful in the treatment of fibrotic conditions such as idiopathic pulmonary fibrosis, renal fibrosis, postoperative stricture, keloid scar formation, scleroderma (including morphea) and cardiac fibrosis. Bromodomain inhibitors may be useful in the treatment of a variety of diseases associated with bone remodelling such as osteoporosis, osteopetrosis, pycnodysostosis, Paget's disease of bone, familial expanile osteolysis, expansile skeletal hyperphosphatasia, hyperososis corticalis deformans Juvenilis, juvenile Paget's disease and Camurati

Engelmann disease. Bromodomain inhibitors may be useful in the treatment of viral infections such as herpes virus, human papilloma virus, adenovirus and poxvirus and other DNA viruses. Bromodomain inhibitors may be useful in the treatment of cancer, including hematological (such as leukaemia, lymphoma and multiple myeloma), epithelial including lung, breast and colon carcinomas, midline carcinomas, mesenchymal, hepatic, renal and neurological tumours. Bromodomain inhibitors may be useful in the treatment of one or more cancers selected from brain cancer (gliomas), glioblastomas, Bannayan-Zonana syndrome, Cowden disease, Lhermitte-Duclos disease, breast cancer, inflammatory breast cancer, colorectal cancer, Wilm's tumor, Ewing's sarcoma, rhabdomyosarcoma, ependymoma, medulloblastoma, colon cancer, head and neck cancer, kidney cancer, lung cancer, liver cancer, melanoma, squamous cell carcinoma, ovarian cancer, pancreatic cancer, prostate cancer, sarcoma cancer, osteosarcoma, giant cell tumor of bone, thyroid cancer,

lymphoblastic T-cell leukemia, chronic myelogenous leukemia, chronic lymphocytic leukemia, hairy-cell leukemia, acute lymphoblastic leukemia, acute myelogenous leukemia, chronic neutrophilic leukemia, acute lymphoblastic T-cell leukemia, acute myeloid leukemia, plasmacytoma, immunoblastic large cell leukemia, mantle cell leukemia, multiple myeloma, megakaryoblastic leukemia, acute megakaryocytic leukemia, promyelocytic leukemia, mixed lineage leukaemia, erythroleukemia, malignant lymphoma, Hodgkins lymphoma, non- Hodgkins lymphoma, lymphoblastic T-cell lymphoma, Burkitt's lymphoma, follicular lymphoma, neuroblastoma, bladder cancer, urothelial cancer, vulval cancer, cervical cancer, endometrial cancer, renal cancer, mesothelioma, esophageal cancer, salivary gland cancer, hepatocellular cancer, gastric cancer, nasopharangeal cancer, buccal cancer, cancer of the mouth, GIST (gastrointestinal stromal tumor) and testicular cancer. In one embodiment the cancer is a leukaemia, for example a leukaemia selected from acute monocytic leukemia, acute myelogenous leukemia, chronic myelogenous leukemia, chronic lymphocytic leukemia, acute myeloid leukemia and mixed lineage leukaemia (MLL). In another embodiment the cancer is multiple myeloma. In another embodiment the cancer is a lung cancer such as small cell lung cancer (SCLC). In another embodiment the cancer is a neuroblastoma. In another embodiment the cancer is Burkitt's lymphoma. In another embodiment the cancer is cervical cancer. In another embodiment the cancer is esophageal cancer. In another embodiment the cancer is ovarian cancer. In another embodiment the cancer is breast cancer. In another embodiment the cancer is colarectal cancer. In one embodiment the disease or condition for which a bromodomain inhibitor is indicated is selected from diseases associated with systemic inflammatory response syndrome, such as sepsis, burns, pancreatitis, major trauma, haemorrhage and ischaemia. In this embodiment the

bromodomain inhibitor would be administered at the point of diagnosis to reduce the incidence of: SIRS, the onset of shock, multi-organ dysfunction syndrome, which includes the onset of acute lung injury, ARDS, acute renal, hepatic, cardiac or gastro-intestinal injury and mortality. In another embodiment the bromodomain inhibitor would be administered prior to surgical or other procedures associated with a high risk of sepsis, haemorrhage, extensive tissue damage, SIRS or MODS (multiple organ dysfunction syndrome). In a particular embodiment the disease or condition for which a bromodomain inhibitor is indicated is sepsis, sepsis syndrome, septic shock and endotoxaemia. In another embodiment, the bromodomain inhibitor is indicated for the treatment of acute or chronic pancreatitis. In another embodiment the bromodomain is indicated for the treatment of burns. In one embodiment the disease or condition for which a bromodomain inhibitor is indicated is selected from herpes simplex infections and reactivations, cold sores, herpes zoster infections and reactivations, chickenpox, shingles, human papilloma virus, human immunodeficiency virus (HIV), cervical neoplasia, adenovirus infections, including acute respiratory disease, poxvirus infections such as cowpox and smallpox and African swine fever virus. In one particular embodiment a bromodomain inhibitor is indicated for the treatment of Human papilloma virus infections of skin or cervical epithelia. In one

embodiment the bromodomain inhibitor is indicated for the treatment of latent HIV infection.

The present invention thus provides a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in therapy. In one embodiment there is provided a compound of formula (IA) or a pharmaceutically acceptable salt thereof for use in therapy. In one embodiment there is provided a compound of formula (I B) or a pharmaceutically acceptable salt thereof for use in therapy. The present invention thus provides a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of any diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated. In one embodiment there is provided a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of any diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated. In another embodiment there is provided a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of chronic auto-immune and/or inflammatory conditions. In another embodiment there is provided a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of chronic auto-immune conditions. In another embodiment there is provided a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of inflammatory conditions. In another embodiment there is provided a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of viral infections. In a further embodiment there is provided a compound of formula (I) or a pharmaceutically acceptable salt thereof for use in the treatment of cancer.

Also provided is the use of a compound of formula (I), or a pharmaceutically acceptable salt thereof, in the manufacture of a medicament for the treatment of diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated. In another embodiment there is provided the use of a compound of formula (I), or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of chronic auto-immune conditions. In another embodiment there is provided the use of a compound of formula (I) or a pharmaceutically acceptable salt thereof for the manufacture of a medicament for the treatment of inflammatory conditions. In another embodiment there is provided the use of a compound of formula (I), or a pharmaceutically acceptable salt thereof, for the manufacture of a medicament for the treatment of viral infections. In another embodiment there is provided the use of a compound of formula (I) or a pharmaceutically acceptable salt thereof for the manufacture of a medicament for the treatment of cancer.

Also provided is a method of treating diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated in a subject in need thereof which comprises

administering a therapeutically effective amount of compound of formula (I) or a

pharmaceutically acceptable salt thereof. In another embodiment there is provided a method of treating chronic auto-immune conditions which comprises administering a therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof. In another embodiment there is provided a method of treating inflammatory conditions comprising administering a therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof. In another embodiment there is provided a method of treating viral infections comprising administering a therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof. In another embodiment there is provided a method of treating cancer comprising administering a therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof. Suitably the subject in need thereof is a mammal, particularly a human.

As used herein, the term "effective amount" means that amount of a drug or pharmaceutical agent that will elicit the biological or medical response of a tissue, system, or subject (e.g. a human) that is being sought, for instance, by a researcher or clinician.

Furthermore, the term "therapeutically effective amount" means any amount which, as compared to a corresponding subject who has not received such amount, results in improved treatment, healing, or amelioration of a disease, disorder, or side effect, or a decrease in the rate of advancement of a disease or disorder. The term also includes within its scope amounts effective to enhance normal physiological function.

The term "diseases or conditions for which a BRPF1 bromodomain inhibitor is indicated", is intended to include each of or all of the above diseases or conditions. While it is possible that for use in therapy, a compound of formula (I) as well as pharmaceutically acceptable salts thereof may be administered alone, it is common to present the active ingredient as a pharmaceutical composition. The present invention therefore provides in a further aspect a pharmaceutical composition comprising a compound of formula (I) or a pharmaceutically acceptable salt and one or more pharmaceutically acceptable excipients. In one embodiment there is provided a pharmaceutical composition comprising a compound of formula (IA) or a pharmaceutically acceptable salt and one or more pharmaceutically acceptable excipients. The compound of formula (I) and

pharmaceutically acceptable salts, are as described above. The excipient(s) must be acceptable in the sense of being compatible with the other ingredients of the composition and not deleterious to the recipient thereof. In accordance with another aspect of the invention there is also provided a process for the preparation of a pharmaceutical composition including admixing a compound of formula (I), or a pharmaceutically acceptable salt thereof, with one or more pharmaceutically acceptable excipients.

Suitable pharmaceutically acceptable excipients include the following types of excipients: carriers, diluents, fillers, binders, disintegrants, lubricants, glidants, granulating agents, coating agents, wetting agents, solvents, co-solvents, suspending agents, emulsifiers, sweeteners, flavoring agents, flavor masking agents, coloring agents, anti-caking agents, humectants, chelating agents, plasticizers, viscosity increasing agents, antioxidants, preservatives, stabilizers, surfactants, and buffering agents. The skilled artisan will appreciate that certain pharmaceutically acceptable excipients may serve more than one function and may serve alternative functions depending on how much of the excipient is present in the formulation and what other ingredients are present in the formulation.

Skilled artisans possess the knowledge and skill in the art to enable them to select suitable pharmaceutically acceptable excipients in appropriate amounts for use in the invention. In addition, there are a number of resources that are available to the skilled artisan which describe pharmaceutically acceptable excipients and may be useful in selecting suitable pharmaceutically acceptable excipients. Examples include Remington's Pharmaceutical Sciences (Mack Publishing Company), The Handbook of Pharmaceutical Additives (Gower Publishing Limited), and The Handbook of Pharmaceutical Excipients (the American Pharmaceutical Association and the Pharmaceutical Press).

The pharmaceutical compositions of the invention are prepared using techniques and methods known to those skilled in the art. Some of the methods commonly used in the art are described in Remington's Pharmaceutical Sciences (Mack Publishing Company). The pharmaceutical composition can be used in the treatment of any of the conditions described herein. Since the compound of formula (I) is intended for use in pharmaceutical

compositions it will be readily understood that it is preferably provided in substantially pure form, for example, at least 85% pure, especially at least 98% pure (% in a weight for weight basis). Pharmaceutical compositions may be presented in unit dose forms containing a predetermined amount of active ingredient per unit dose. Preferred unit dosage

compositions are those containing a daily dose or sub-dose, or an appropriate fraction thereof, of an active ingredient. Such unit doses may therefore be administered more than once a day. Preferred unit dosage compositions are those containing a daily dose or sub- dose (for administration more than once a day), as herein above recited, or an appropriate fraction thereof, of an active ingredient.

Pharmaceutical compositions may be adapted for administration by any appropriate route, for example by the oral (including buccal or sublingual), rectal, inhaled, intranasal, topical (including buccal, sublingual or transdermal), ocular (including topical, intraocular, subconjunctival, episcleral, sub-Tenon), vaginal or parenteral (including subcutaneous, intramuscular, intravenous or intradermal) route. Such compositions may be prepared by any method known in the art of pharmacy, for example by bringing into association the active ingredient with the excipient(s). In one embodiment the pharmaceutical composition is adapted for parenteral administration, particularly intravenous administration. In one embodiment the pharmaceutical composition is adapted for oral administration. In one embodiment the pharmaceutical composition is adapted for topical administration.

Pharmaceutical compositions adapted for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the composition isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. The compositions may be presented in unit-dose or multi-dose containers, for example sealed ampoules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water, for injections immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets.

Pharmaceutical compositions adapted for oral administration may be presented as discrete units such as capsules or tablets; powders or granules; solutions or suspensions in aqueous or non-aqueous liquids; edible foams or whips; or oil-in-water liquid emulsions or water-in-oil liquid emulsions. For instance, for oral administration in the form of a tablet or capsule, the active drug component can be combined with an oral, non-toxic

pharmaceutically acceptable inert carrier such as ethanol, glycerol, water and the like.

Powders suitable for incorporating into tablets or capsules may be prepared by reducing the compound to a suitable fine size (e.g. by micronisation) and mixing with a similarly prepared pharmaceutical carrier such as an edible carbohydrate, for example, starch or mannitol. Flavouring, preservative, dispersing and colouring agent can also be present. Capsules may be made by preparing a powder mixture, as described above, and filling formed gelatin sheaths. Glidants and lubricants such as colloidal silica, talc, magnesium stearate, calcium stearate or solid polyethylene glycol can be added to the powder mixture before the filling operation. A disintegrating or solubilizing agent such as agar-agar, calcium carbonate or sodium carbonate can also be added to improve the availability of the medicament when the capsule is ingested. Moreover, when desired or necessary, suitable binders, glidants, lubricants, sweetening agents, flavours, disintegrating agents and colouring agents can also be incorporated into the mixture. Suitable binders include starch, gelatin, natural sugars such as glucose or beta-lactose, corn sweeteners, natural and synthetic gums such as acacia, tragacanth or sodium alginate, carboxymethylcellulose, polyethylene glycol, waxes and the like. Lubricants used in these dosage forms include sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate, sodium chloride and the like.

Disintegrators include starch, methyl cellulose, agar, bentonite, xanthan gum and the like. Tablets are formulated, for example, by preparing a powder mixture, granulating or slugging, adding a lubricant and disintegrant and pressing into tablets. A powder mixture is prepared by mixing the compound, suitably comminuted, with a diluent or base as described above, and optionally, with a binder such as carboxymethylcellulose, an aliginate, gelatin, or polyvinyl pyrrolidone, a solution retardant such as paraffin, a resorption accelerator such as a quaternary salt and/or an absorption agent such as bentonite, kaolin or dicalcium phosphate. The powder mixture can be granulated by wetting with a binder such as syrup, starch paste, acadia mucilage or solutions of cellulosic or polymeric materials and forcing through a screen. As an alternative to granulating, the powder mixture can be run through the tablet machine and the result is imperfectly formed slugs broken into granules. The granules can be lubricated to prevent sticking to the tablet forming dies by means of the addition of stearic acid, a stearate salt, talc or mineral oil. The lubricated mixture is then compressed into tablets. The compound of formula (I) and pharmaceutically acceptable salts thereof, can also be combined with a free flowing inert carrier and compressed into tablets directly without going through the granulating or slugging steps. A clear or opaque protective coating consisting of a sealing coat of shellac, a coating of sugar or polymeric material and a polish coating of wax can be provided. Dyestuffs can be added to these coatings to distinguish different unit dosages.

Oral fluids such as solutions, syrups and elixirs can be prepared in dosage unit form so that a given quantity contains a predetermined amount of the compound. Syrups can be prepared by dissolving the compound in a suitably flavoured aqueous solution, while elixirs are prepared through the use of a non-toxic alcoholic vehicle. Suspensions can be formulated by dispersing the compound in a non-toxic vehicle. Solubilizers and emulsifiers such as ethoxylated isostearyl alcohols and polyoxy ethylene sorbitol ethers, preservatives, flavour additive such as peppermint oil or natural sweeteners or saccharin or other artificial sweeteners, and the like can also be added.

Compositions for administration (e.g. oral administration) may be designed to provide a modified release profile so as to sustain or otherwise control the release of the

therapeutically active agent. A modified release profile of the therapeutically active agent may be obtained through the design of polymeric matrices incorporating different choices and properties of biodegradable/bioerodable polymers (e.g. poly(ethylene vinyl) acetate (EVA), superhydrolyzed PVA), hydroxyalkyl cellulose (HPC), methylcellulose (MC), hydroxypropyl methyl cellulose (HPMC), polycaprolactone, poly(glycolic) acid, poly(lactic) acid, polyanhydride, of polymer molecular weights, polymer crystallinity, copolymer ratios, processing conditions, surface finish, geometry, excipient addition and polymeric coatings that will enhance drug diffusion, erosion, dissolution and osmosis. Where appropriate, dosage unit compositions for oral administration can be microencapsulated. The

composition may be prepared to prolong or sustain the release as for example by coating or embedding particulate material in polymers, wax or the like. The compound of formula (I) and pharmaceutically acceptable salts thereof, can also be administered in the form of liposome delivery systems, such as small unilamellar vesicles, large unilamellar vesicles and multilamellar vesicles. Liposomes can be formed from a variety of phospholipids, such as cholesterol, stearylamine or phosphatidylcholines. Pharmaceutical compositions adapted for topical administration may be formulated as ointments, creams, suspensions, emulsions, lotions, powders, solutions, pastes, gels, foams, sprays, aerosols or oils. Such

pharmaceutical compositions may include conventional additives which include, but are not limited to, preservatives, solvents to assist drug penetration, co-solvents, emollients, propellants, viscosity modifying agents (gelling agents), surfactants and carriers.

In one embodiment there is provided a pharmaceutical composition adapted for topical administration which comprises between 0.01 - 10%, or between 0.01 - 1 % of the compound of formula (I), or a pharmaceutically acceptable salt thereof, by weight of the composition. For treatments of the eye or other external tissues, for example mouth and skin, the compositions are preferably applied as a topical ointment, cream, gel, spray or foam. When formulated in an ointment, the active ingredient may be employed with either a paraffinic or a water-miscible ointment base. Alternatively, the active ingredient may be formulated in a cream with an oil-in-water cream base or a water-in-oil base. Pharmaceutical compositions adapted for topical administrations to the eye include eye drops wherein the active ingredient is dissolved or suspended in a suitable carrier, especially an aqueous solvent. Compositions to be administered to the eye will have ophthalmically compatible pH and osmolality. One or more ophthalmically acceptable pH adjusting agents and/or buffering agents can be included in a composition of the invention, including acids such as acetic, boric, citric, lactic, phosphoric and hydrochloric acids; bases such as sodium hydroxide, sodium phosphate, sodium borate, sodium citrate, sodium acetate, and sodium lactate; and buffers such as citrate/dextrose, sodium bicarbonate and ammonium chloride. Such acids, bases, and buffers can be included in an amount required to maintain pH of the composition in an ophthalmically acceptable range. One or more ophthalmically acceptable salts can be included in the composition in an amount sufficient to bring osmolality of the composition into an ophthalmically acceptable range. Such salts include those having sodium, potassium or ammonium cations and chloride, citrate, ascorbate, borate, phosphate, bicarbonate, sulfate, thiosulfate or bisulfite anions. The ocular delivery device may be designed for the controlled release of one or more therapeutic agents with multiple defined release rates and sustained dose kinetics and permeability. Pharmaceutical compositions for ocular delivery also include in situ gellable aqueous composition. Such a composition comprises a gelling agent in a concentration effective to promote gelling upon contact with the eye or with lacrimal fluid. Suitable gelling agents include but are not limited to thermosetting polymers. The term "in situ gellable" as used herein is includes not only liquids of low viscosity that form gels upon contact with the eye or with lacrimal fluid, but also includes more viscous liquids such as semi-fluid and thixotropic gels that exhibit substantially increased viscosity or gel stiffness upon administration to the eye. See, for example, Ludwig (2005) Adv. Drug Deliv. Rev.

3;57: 1595-639, herein incorporated by reference for purposes of its teachings of examples of polymers for use in ocular drug delivery. Dosage forms for nasal or inhaled administration may conveniently be formulated as aerosols, solutions, suspensions, gels or dry powders. For compositions suitable and/or adapted for inhaled administration, it is preferred that the compound of formula (I) or a pharmaceutically acceptable salt thereof, is in a particle-size-reduced form e.g. obtained by micronisation. The preferable particle size of the size-reduced (e.g. micronised) compound or salt is defined by a D 50 value of about 0.5 to about 10 microns (for example as measured using laser diffraction). Aerosol formulations, e.g. for inhaled administration, can comprise a solution or fine suspension of the active substance in a pharmaceutically acceptable aqueous or non-aqueous solvent. Aerosol formulations can be presented in single or multidose quantities in sterile form in a sealed container, which can take the form of a cartridge or refill for use with an atomising device or inhaler. Alternatively the sealed container may be a unitary dispensing device such as a single dose nasal inhaler or an aerosol dispenser fitted with a metering valve (metered dose inhaler) which is intended for disposal once the contents of the container have been exhausted. Where the dosage form comprises an aerosol dispenser, it preferably contains a suitable propellant under pressure such as compressed air, carbon dioxide or an organic propellant such as a

hydrofluorocarbon (HFC). Suitable HFC propellants include 1 ,1 ,1 ,2,3,3,3- heptafluoropropane and 1 ,1 ,1 ,2-tetrafluoroethane. The aerosol dosage forms can also take the form of a pump-atomiser. The pressurised aerosol may contain a solution or a suspension of the active compound. This may require the incorporation of additional excipients e.g. co-solvents and/or surfactants to improve the dispersion characteristics and homogeneity of suspension formulations. Solution formulations may also require the addition of co-solvents such as ethanol. For pharmaceutical compositions suitable and/or adapted for inhaled administration, the pharmaceutical composition may be a dry powder inhalable composition. Such a composition can comprise a powder base such as lactose, glucose, trehalose, mannitol or starch, the compound of formula (I) or a pharmaceutically acceptable salt thereof (preferably in particle-size-reduced form, e.g. in micronised form), and optionally a performance modifier such as L-leucine or another amino acid and/or metal salt of stearic acid such as magnesium or calcium stearate. Preferably, the dry powder inhalable composition comprises a dry powder blend of lactose e.g. lactose monohydrate and the compound of formula (I) or salt thereof. Such compositions can be administered to the patient using a suitable device such as the DISKUS® device, marketed by

GlaxoSmithKline which is for example described in GB 2242134 A.

The compound of formula (I) and pharmaceutically acceptable salts thereof may be formulated as a fluid formulation for delivery from a fluid dispenser, for example a fluid dispenser having a dispensing nozzle or dispensing orifice through which a metered dose of the fluid formulation is dispensed upon the application of a user-applied force to a pump mechanism of the fluid dispenser. Such fluid dispensers are generally provided with a reservoir of multiple metered doses of the fluid formulation, the doses being dispensable upon sequential pump actuations. The dispensing nozzle or orifice may be configured for insertion into the nostrils of the user for spray dispensing of the fluid formulation into the nasal cavity. A fluid dispenser of the aforementioned type is described and illustrated in WO- A-2005/044354.

A therapeutically effective amount of a compound of formula (I) or a pharmaceutically acceptable salt thereof, will depend upon a number of factors including, for example, the age and weight of the subject, the precise condition requiring treatment and its severity, the nature of the formulation, and the route of administration, and will ultimately be at the discretion of the attendant physician or veterinarian. In the pharmaceutical composition, each dosage unit for oral or parenteral administration preferably contains from 0.01 to 3000 mg, more preferably 0.5 to 1000 mg, of a compound of formula (I) or a pharmaceutically acceptable salt thereof, calculated as the free base. Each dosage unit for nasal or inhaled administration preferably contains from 0.001 to 50 mg, more preferably 0.01 to 5 mg, of a compound of the formula (I) or a pharmaceutically acceptable salt thereof, calculated as the free base. The pharmaceutically acceptable compound of formula (I) and pharmaceutically acceptable salts thereof, can be administered in a daily dose (for an adult patient) of, for example, an oral or parenteral dose of 0.01 mg to 3000 mg per day, 0.5 to 1000 mg per day or 100 mg to 2500mg per day, or a nasal or inhaled dose of 0.001 to 50 mg per day or 0.01 to 5 mg per day, of the compound of the formula (I) or a pharmaceutically acceptable salt thereof, calculated as the free base. This amount may be given in a single dose per day or more usually in a number (such as two, three, four, five or six) of sub-doses per day such that the total daily dose is the same. An effective amount of a salt thereof, may be determined as a proportion of the effective amount of the compound of formula (I) per se.

The compound of formula (I) and pharmaceutically acceptable salts thereof, and may be employed alone or in combination with other therapeutic agents, for example kinase inhibitors or anti-TNF-alpha agents. Combination therapies according to the present invention thus comprise the administration of at least one compound of formula (I) or a pharmaceutically acceptable salt thereof, and the use of at least one other therapeutically active agent. Preferably, combination therapies according to the present invention comprise the administration of at least one compound of formula (I) or a pharmaceutically acceptable salt thereof, and at least one other therapeutically active agent. The compound(s) of formula (I) and pharmaceutically acceptable salts thereof, and the other therapeutically active agent(s) may be administered together in a single pharmaceutical composition or separately and, when administered separately this may occur simultaneously or sequentially in any order. The amounts of the compound(s) of formula (I) and pharmaceutically acceptable salts thereof, and the other therapeutically active agent(s) and the relative timings of

administration will be selected in order to achieve the desired combined therapeutic effect. Thus in a further aspect, there is provided a combination comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof, and at least one other therapeutically active agent. Thus in one aspect, the compound of formula (I) or a pharmaceutically acceptable salt thereof, and pharmaceutical compositions comprising a compound of formula (I) or a pharmaceutically acceptable salt thereof, according to the invention may be used in combination with or include one or more other therapeutic agents, for example selected from antibiotics, anti-virals, glucocorticosteroids, muscarinic antagonists beta-2 agonists and Vitamin D3 analogues. In a further embodiment a compound of formula (I) or a pharmaceutically acceptable salt thereof may be used in combination with a further therapeutic agent which is suitable for the treatment of cancer. Examples of such further therapeutic agents are described in Cancer Principles and Practice of Oncology by V.T. Devita and S. Hellman (editors), 6 th edition (2001 ), Lippincott Williams & Wilkins Publishers. A person of ordinary skill in the art would be able to discern which combinations of agents would be useful based on the particular characteristics of the drugs and the cancer involved. Further therapeutic agents to be used in combination with the compound of formula (I) or a pharmaceutically acceptable salt thereof include, but are not limited to, anti-microtubule agents (such as diterpenoids and vinca alkaloids); platinum coordination complexes;

alkylating agents (such as nitrogen mustards, oxazaphosphorines, alkylsulfonates, nitrosoureas, and triazenes); antibiotic agents (such as anthracyclins, actinomycins and bleomycins); topoisomerase II inhibitors (such as epipodophyllotoxins); antimetabolites (such as purine and pyrimidine analogues and anti-folate compounds); topoisomerase I inhibitors (such as camptothecins; hormones and hormonal analogues); signal transduction pathway inhibitors (such as tyropsine receptor inhibitors); non-receptor tyrosine kinase angiogenesis inhibitors; immunotherapeutic agents; proapoptotic agents; epigenetic or transcriptional modulators (such as histone deacetylase inhibitors) and cell cycle signalling inhibitors. It will be appreciated that when the compound of formula (I) or a pharmaceutically acceptable salt thereof, is administered in combination with other therapeutic agents normally administered by the inhaled, intravenous, oral or intranasal route, that the resultant pharmaceutical composition may be administered by the same routes. Alternatively the individual components of the composition may be administered by different routes. One embodiment of the invention encompasses combinations comprising one or two other therapeutic agents. It will be clear to a person skilled in the art that, where appropriate, the other therapeutic ingredient(s) may be used in the form of salts, for example as alkali metal or amine salts or as acid addition salts, or prodrugs, or as esters, for example lower alkyl esters, or as solvates, for example hydrates, to optimise the activity and/or stability and/or physical characteristics, such as solubility, of the therapeutic ingredient. It will be clear also that, where appropriate, the therapeutic ingredients may be used in optically pure form. The combinations referred to above may conveniently be presented for use in the form of a pharmaceutical composition and thus pharmaceutical compositions comprising a

combination as defined above together with a pharmaceutically acceptable excipient represent a further aspect of the invention.

The compound of formula (I) and pharmaceutically acceptable salts thereof, may be prepared by the methods described below or by similar methods. Thus the following Intermediates and Examples serve to illustrate the preparation of the compound of formula (I) and pharmaceutically acceptable salts thereof, and are not to be considered as limiting the scope of the invention in any way.

General Experimental details

All temperatures referred to are in °C. The names of the following compounds have been obtained using the compound naming programme "ACD Name Pro 6.02" or Chem Draw Ultra 12.0.

Abbreviations

Ac 2 0 acetic anhydride

CHCI 3 chloroform

DCM dichloromethane

DIPEA Λ/,/V-diisopropylethylamine

DMF Λ/,/V-dimethylformamide

DMSO dimethylsulfoxide

DMSO-c/ 6 deuterated dimethylsulfoxide

Et 3 N triethylamine

EtOAc ethyl acetate

EtOH ethanol

h hour(s)

HPLC high performance liquid chromatography

/ ' PrOH / ' so-propyl alcohol

LCMS liquid chromatography— mass spectrometry

M molar (concentration)

MeCN acetonitrile

Mel iodomethane

MeOH methanol

min minute(s)

N normal (concentration)

Na 2 S0 4 sodium sulphate

Pd/C palladium on carbon

Rt retention time

TFA trifluoroacetic acid

THF tetrahydrofuran

UPLC Ultra performance liquid chromatograpy

LCMS methodology

Formate

LC conditions

The UPLC analysis was conducted on an Acquity UPLC BEH C18 column (50 mm x 2.1 mm, i.d. 1.7 μηη packing diameter) at 40'C.

The solvents employed were:

A = 0.1 % v/v solution of formic acid in water

B = 0.1 % v/v solution of formic acid in acetonitrile 0 1 97 3

1.5 1 0 100

1.9 1 0 100

2.0 1 97 3

The UV detection was a summed signal from wavelength of 210 nm to 350 nm.

MS conditions

MS Waters ZQ

lonisation mode Alternate-scan positive and negative electrospray

Scan range 100 to 1000 AMU

Scan time 0.27 sec

Inter scan delay 0.10 sec

High pH

LC conditions

The UPLC analysis was conducted on an Acquity UPLC BEH C18 column (50 mm x 2.1 mm, i.d. 1.7 μηη packing diameter) at 40'C.

The solvents employed were:

A = 10 mM ammonium bicarbonate in water adjusted to pH 10 with ammonia solution B = Acetonitrile

The UV detection was a summed signal from wavelength of 210 nm to 350 nm.

MS conditions

MS Waters ZQ

lonisation mode Alternate-scan positive and negative electrospray

Scan range 100 to 1000 AMU

Scan time 0.27 sec

Inter scan delay 0.10 sec

HPLC methodology

Method B. High pH Focused Preparative LC/MS

LC Conditions

The HPLC analysis was conducted on an XBridge C18 column (100 mm x 30 mm i.d. 5 μηη packing diameter) at ambient temperature.

The solvents employed were:

A = 10 mM Ammonium Bicarbonate in water adjusted to pH 10 with ammonia solution. B = Acetonitrile. The gradient employee was:

Time (min) Flow Rate (ml/min) % A % B

0 40 85 15

1 40 85 15

10 40 45 55

1 1 40 1 99

15 40 1 99

The UV detection was an averaged signal from wavelength of 210 nm to 350 nm.

Injection Volume : 3 ml_

MS Conditions

MS Waters ZQ

lonisation mode Alternate-scan Positive and Negative Electrospray

Scan Range 150 to 1500 AMU

Scan Time 0.50 seconds

Inter scan delay 0.25 seconds

Method C. High pH Focused Preparative LC/MS

Method for 300 mg loading with At Column Dilution

LC Conditions

The HPLC analysis was conducted on an XSELECT CSH C18 column (150 mm x 30 mm i.d. 5 μηη packing diameter) at ambient temperature.

The solvents employed were:

A = 10 mM Ammonium Bicarbonate in water adjusted to pH 10 with ammonia solution.

B = Acetonitrile.

The UV detection was for a signal wavelength at 254nm.

Injection Volume : 3 mL

MS Conditions

MS Waters ZQ

lonisation mode Alternate-scan Positive and Negative Electrospray

Scan Range 100 to 1000 AMU

Scan Time 0.50 seconds

Inter scan delay 0.2 seconds NMR

Spectra were recorded on a Bruker nanobay 400 MHz or a Bruker AVII+ 600 MHz spectrometers at either 302 K or for VT spectra at 392-393 K and are referenced as follows: 1 H-NMR (400 -or 600- MHZ), internal standard TMS at δ = 0.00; 13 C-NMR (100.6 -or 150.9- MHz), internal standard CDCI 3 at δ = 77.23 or DMSO-D 6 at δ = 39.70

Example 1

Step 1

5-fluoro-1 H-benzordlimidazol-2(3H)-one

A stirred solution of 4-fluorobenzene-1 ,2-diamine (15.1 g, 120 mmol) in THF (120 mL) under nitrogen was cooled using an ice-bath and then was treated with di(1 -/-imidazol-1 - yl)methanone (23.4 g, 144 mmol) portion-wise over 15 min. The resulting mixture was slowly warmed to room temperature then was concentrated in vacuo after 2.5 h. The residue was suspended in a mixture of water and DCM (250 mL each) and filtered off. This residue was then washed with water (50 mL) and DCM (50 mL), before being dried at 40 °C under vacuum for 16 h to give the title compound (16.0 g, 105 mmol, 88%) as a brown solid.

LCMS (high pH): Rt 0.57 min; [M-H + ] " = 151.1

δ Η NMR (400 MHz, DMSO-d 6 ) ppm 10.73 (br s, 1 H), 10.61 (br s, 1 H), 6.91-6.84 (m, 1 H), 6.78-6.70 (m, 2H).

Step 2

5-fluoro-1 ,3-dimethyl-1 /-/-benzo[dlimidazol-2(3/-/)-one

A solution of 5-fluoro-1 H-benzo[d]imidazol-2(3H)-one (16.0 g, 105 mmol) in DMF (400 mL) under nitrogen was cooled with an ice-bath, using a mechanical stirrer for agitation. It was then treated over 10 min with sodium hydride (60% w/w in mineral oil, 13.1 g, 327 mmol) and the resulting mixture was stirred at this temperature for 30 min before being treated with iodomethane (26.3 mL, 422 mmol) over 30 min. The resulting mixture was then allowed to warm to room temperature and after 1 h was carefully treated with water (500 mL). The aqueous phase was extracted with EtOAc (3 x 800 mL) and the combined organics were washed with brine (1 L), dried over MgS0 4 and concentrated in vacuo. Purification of the brown residue by flash chromatography on silica gel (SP4, 1.5 kg column, gradient: 0 to 25% (3: 1 EtOAc/EtOH) in cyclohexane) gave the title compound (15.4 g, 86 mmol, 81 %) as a pink solid.

LCMS (high pH): Rt 0.76 min; [M+H + ] + = 181.1

δ Η NMR (400 MHz, CDCI 3 ) ppm 6.86-6.76 (m, 2H), 6.71 (dd, J = 8.3, 2.3 Hz, 1 H), 3.39 (s, 3H), 3.38 (s, 3H).

Step 3

5-fluoro-1 ,3-dimethyl-6-nitro-1 /-/-benzordlimidazol-2(3/-/)-one

A stirred solution of 5-fluoro-1 ,3-dimethyl-1 H-benzo[d]imidazol-2(3/-/)-one (4.55 g, 25.3 mmol) in acetic anhydride (75 mL) under nitrogen was cooled to -30 °C and then was slowly treated with fuming nitric acid (1 .13 mL, 25.3 mmol) making sure that the temperature was kept below -25°C. The solution turned brown once the first drop of acid was added and a thick brown precipitate formed after the addition was complete. The mixture was allowed to slowly warm up to 0 °C then was carefully treated after 1 h with ice-water (100 mL). EtOAc (15 mL) was then added and the resulting mixture was stirred for 20 min. The precipitate formed was filtered off, washed with water (10 mL) and EtOAc (10 mL), and then was dried under vacuum at 40 °C for 16 h to give the title compound (4.82 g, 21 .4mmol, 85%) as a yellow solid.

LCMS (high pH): Rt 0.76 min; [M+H + ] + not detected

δ Η NMR (600 MHz, DMSO-d 6 ) ppm 7.95 (d, J = 6.4 Hz, 1 H, (H-7)), 7.48 (d, J = 1 1.7 Hz, 1 H, (H-4)), 3.38 (s, 3H, (H-10)), 3.37 (s, 3H, (H-12)).

δ 0 NMR (151 MHz, DMSO-d 6 ) ppm 154.3 (s, 1 C, (C-2)), 152.3 (d, J = 254.9 Hz, 1 C, (C-5)), 135.5 (d, J = 13.0 Hz, 1 C, (C-9)), 130.1 (d, J = 8.0 Hz, 1 C, (C-6)), 125.7 (s, 1 C, (C-8)), 104.4 (s, 1 C, (C-7)), 97.5 (d, J = 28.5 Hz, 1 C, (C-4)), 27.7 (s, 1 C, (C-12)), 27.4 (s, 1 C, (C-10)). Step 4

(R)-tert-but \ 4-( 1 ,3-dimethyl-6-nitro-2-oxo-2,3-dihydro-1 H-benzordlimidazol-5-yl)-3- methylpiperazine-1-carboxylate

A stirred suspension of 5-fluoro-1 ,3-dimethyl-6-nitro-1 H-benzo[d]imidazol-2(3/-/)-one (0.924 g, 4.10 mmol), (R)-ie f-butyl 3-methylpiperazine-1 -carboxylate (1.23 g, 6.16 mmol), and DI PEA (1 .43 mL, 8.21 mmol) in DMSO (4 mL) was heated to 120 °C in a Biotage Initiator microwave reactor for 13 h, then to 130 °C for a further 10 h. The reaction mixture was concentrated in vacuo then partitioned between EtOAc and saturated aqueous sodium bicarbonate solution. The aqueous was extracted with EtOAc and the combined organics were dried (Na 2 S0 4 ), filtered, and concentrated in vacuo to give a residue which was purified by silica chromatography (0-100% ethyl acetate in cyclohexane) to give the title compound as an orange/yellow solid (1.542 g, 3.80 mmol, 93%).

LCMS (formate): Rt 1.17 min, [M+H + ] + 406.5.

δ Η NMR (400 MHz, CDCI 3 ) ppm 7.36 (s, 1 H), 6.83 (s, 1 H), 4.04-3.87 (m,1 H), 3.87-3.80 (m, 1 H), 3.43 (s, 6H), 3.35-3.25 (m, 1 H), 3.23-3.08 (m, 2H), 3.00-2.72 (m, 2H), 1.48 (s, 9H), 0.81 (d, J = 6.1 Hz, 3H)

Step 5

(RHerf-butyl 4-(6-amino-1 ,3-dimethyl-2-oxo-2,3-dihydro-1 /-/-benzordlimidazol-5-yl)-3- methylpiperazine-1-carboxylate

To (R)-iert-butyl 4-(1 ,3-dimethyl-6-nitro-2-oxo-2,3-dihydro-1 H-benzo[d]imidazol-5-yl)-3- methylpiperazine-1-carboxylate (1 .542 g) in / ' so-propanol (40 mL) was added 5% palladium on carbon (50% paste) (1.50 g) and the mixture was hydrogenated at room temperature and pressure. After 4 h the mixture was filtered, the residue washed with ethanol and DCM, and the filtrate concentrated in vacuo to give a residue which was purified by silica chromatography (50-100% ethyl acetate in cyclohexane) to afford the title compound (1.220 g, 3.25 mmol, 85%) as a cream solid.

LCMS (high pH): Rt 1 .01 min, [M+H + ] + 376.4.

δ Η NMR (400 MHz, CDCI 3 ) ppm 6.69 (s, 1 H), 6.44 (s, 1 H), 4.33-3.87 (m, 4H), 3.36 (s, 3H), 3.35 (s, 3H), 3.20-2.53 (m, 5H), 1.52 (s, 9H), 0.86 (d, J = 6.1 Hz, 3H).

Step 6

(flVferf-butyl 4-(6-(2-methoxybenzamidoV 1 ,3-dimethyl-2-oxo-2,3-dihvdro-1 H- benzordlimidazol-5-yl)-3-methylpiperazine-1 -carboxylate

A stirred solution of (R)-iert-butyl 4-(6-amino-1 ,3-dimethyl-2-oxo-2,3-dihydro-1 /-/- benzo[d]imidazol-5-yl)-3-methylpiperazine-1 -carboxylate (0.254 g, 0.675 mmol) and pyridine (0.164 ml_, 2.025 mmol) in DCM (2 mL) at room temperature was treated 2-methoxybenzoyl chloride (0.182 mL, 1.35 mmol). After 1 h at room temperature the reaction mixture was concentrated in vacuo to give a residue which was taken up in DMSO:MeOH (1 :1 ) and purified by HPLC (Method C, high pH) to give the title compound (0.302 g, 0.592 mmol, 88%) as a white solid.

LCMS (high pH): Rt 1 .27 min, [M+H + ] + 510.5.

δ Η NMR (400 MHz, CDCI 3 ) ppm 10.67 (s, 1 H), 8.53 (s, 1 H), 8.24 (dd, J = 7.8, 1.7 Hz, 1 H), 7.54-7.48 (m, 1 H), 7.18-7.12 (m, 1 H), 7.07 (d, J = 8.1 Hz, 1 H), 6.82 (s, 1 H), 4.27-3.94 (m, 2H), 4.08 (s, 3H), 3.45 (s, 3H), 3.40 (s, 3H), 3.18-2.99 (m, 2H), 2.92-2.70 (m, 3H), 1.50 (s, 9H), 0.87 (d, J = 6.1 Hz, 3H).

Step 7

(R)-N-( 1 ,3-dimethyl-6-(2-methylpiperazin-1 -yl)-2-oxo-2,3-dihydro-1 H-benzordlimidazol-5-yl)- 2-methoxybenzamide

A stirred solution of (R)-ie f-butyl 4-(6-(2-methoxybenzamido)-1 ,3-dimethyl-2-oxo-2,3- dihydro-1 /-/-benzo[d]imidazol-5-yl)-3-methylpiperazine-1-carboxylate (302 mg, 0.592 mmol) in DCM (4 mL) at room temperature was treated with trifluoroacetic acid (3 ml_). After 15 minutes the mixture was concentrated in vacuo to give a residue which was loaded on a solid-phase cation exchange (SCX) cartridge (5 g), washed with MeOH, and then eluted with methanolic ammonia (2 M). The appropriate fractions were combined and concentrated in vacuo to give a white solid (240 mg). Half of this material was taken up in DMSO:MeOH (1 :1 ) and purified by HPLC (Method B, high pH) to give the title compound (101 mg, 0.245 mmol, 41 %) as a white solid.

LCMS (high pH): Rt = 0.90 min, [M+H + ] + 410.5.

δ Η NMR (600 MHz, DMSO-d 6 ) ppm 10.74 (s, 1 H), 8.39 (s, 1 H), 8.05 (dd, J = 7.7, 1.8 Hz, 1 H), 7.57 (ddd, J = 8.3, 7.2, 2.0 Hz, 1 H), 7.29 (d, J = 8.1 Hz, 1 H), 7.23 (s, 1 H), 7.17-7.1 1 (m, 1 H), 4.10 (s, 3H), 3.33 (s, 3H), 3.32 (s, 3H), 3.30 (br s, 1 H), 3.07-3.02 (m, 1 H), 3.02-2.99 (m, 1 H), 2.92-2.87 (m, 1 H), 2.80 (td, J = 1 1.3, 2.7 Hz, 1 H), 2.73 (td, J = 1 1 .0, 2.7 Hz, 1 H), 2.68-2.63 (m, 1 H), 2.55 (dd, J = 12.0, 9.8 Hz, 1 H), 0.71 (d, J = 6.1 Hz, 3H).

δ 0 NMR (151 MHz, DMSO-d 6 ) ppm 162.1 , 156.8, 154.1 , 134.4, 133.2, 131.5, 130.1 , 126.6, 125.7, 121.9, 121.0, 1 12.5, 103.0, 99.4, 56.8, 55.4, 55.3, 53.3, 46.3, 26.8, 26.6, 16.7.

[a D ] 25 °c = -50.1 (c = 0.3, MeOH).

Biological Test Methods

The compound of formula (IA) was tested in one or more of the following assays. Expression and purification of BET and BRPF1 proteins.

BET proteins were produced using protocols given in the literature. 1 6H-Flag-TEV- BRPF1 (622-738) was expressed in E.coli BL21 (DE3) cells. The pellet from the E.coli culture was resuspended in buffer A (50 mM HEPES pH 7.5, 300 mM NaCI, 10 mM imidazole, and 0.5 mM TCEP) plus 0.1 mg/ml lysozyme (Sigma 92971 -50G-F) and 1 μΙ/ml Protease Inhibitor Cocktail (Sigma P8340). Cells were lysed by sonication, on ice, and centrifuged at 100,000 x g for 90 minutes at 4 ° C. The supernatant was applied to a

HisTRAP HP Column (GE Healthcare 17-5248-02) equilibrated with buffer A, washed with ten column volumes buffer A, and the bound protein eluted using a linear gradient of 10-500 mM imidazole over twenty column volumes. Eluted BRPF1 protein was cleaved with rTEV protease at a ratio of 1 :200, and dialysed overnight at 4°C against buffer B (50 mM HEPES pH 7.5, 150 mM NaCI and 0.5 mM TCEP) using SnakeSkin Dialysis Tubing 3.5K MWCO (Thermo Scientific #68035). Cleaved protein was applied to a HiLoad 26/60 Superdex 75 prep grade size exclusion column (GE Healthcare 45-002-489), equilibrated with buffer B. Fractions containing BRPF1 were pooled, concentrated to 5.9 mg/ml using an Amicon Ultra- 15 Centrifugal Filter Unit with Ultracel-3 membrane (Millipore UFC900308), aliquoted and stored at -80°C. Protein identity was confirmed by peptide mass fingerprinting and predicted molecular weight confirmed by Liquid Chromatography/Mass Spectrometry. Expression and purification of BRPF2 and BRPF3 proteins

BRPF1 , 2 and 3 TR-FRET assays.

Compounds were screened against 6H-Flag-Tev-BRPF1 (622-738), 6HisFlag-Tev- BRPF2 (also known as BRD1 ) (551 -673) or 6His-Flag-Tev-BRPF3 (579-706) protein in dose- response format in a TR-FRET assay measuring competition between test compound and a synthetic fluorescent ligand. Compounds were titrated from 10 mM in 100% DMSO and 100 nl_ transferred to a low volume black 384 well micro titre plate using a Labcyte Echo 555. A Thermo Scientific Multidrop Combi was used to dispense 5 μΙ_ of 4 nM BRPF1 , 20 nM BRPF2 or 40 nM BRPF3 protein respectively in an assay buffer of 50 mM HEPES, 150 mM NaCI, 5% glycerol, 1 mM DTT and 1 mM CHAPS, pH 7.4, and in the presence of the appropriate fluorescent ligand concentration (~K d concentration for the interaction between protein and ligand). After equilibrating for 30 mins in the dark at rt, the bromodomain protein :fluorescent ligand interaction was detected using TR-FRET following a 5 μΙ_ addition of either 3 nM Lanthascreen Elite Tb-anti His antibody (Invitrogen PV5863) for the Alexa 488 ligands, or 3 nM europium chelate labelled anti-6His antibody (Perkin Elmer, W1024, AD01 1 1 ) for the Alexa 647 ligand, in assay buffer. Time resolved fluorescence energy transfer (TR-FRET) was then detected on a time-resolved fluorescence laser equipped Perkin Elmer Envision multimode plate reader using the appropriate protocol (excitation = 337 nm; emission 1 Alexa 488 = 495 nm; emission 2 Alexa 488 = 520 nm, emission 1 Alexa 647 = 615 nm; emission 2 Alexa 647= 665 nm ). TR-FRET ratio was calculated using the following equation: Ratio = ((Acceptor fluorescence at 520 or 665 nm) / (Donor fluorescence at 495 or 615 nm)) * 1000. Data were analysed as for the BRD4 assay.

BRPF1 BRPF2 BRPF3

Alexa Fluor 488 labelled ligand Alexa Fluor 488 labelled ligand Alexa Fluor 647 labelled ligand (ligand binding to BRPF1 ) 100 (ligand binding to BRPF2) 200 (ligand binding to BRPF3) 400 nM nM nM

BRD4 TR-FRET assays.

Compounds were screened against either 6H-Thr BRD4 (1 -477) (Y390A) (BRD4 BD2 mutation to monitor compound binding to BD1 ) or 6H-Thr BRD4 (1 -477) (Y97A) (BRD4 BD1 mutation to monitor compound binding to BD2) in a dose-response format in a TR-FRET assay measuring competition between test compound and an Alexa Fluor 647 derivative of I- BET762. 1 Compounds were titrated from 10 mM in 100% DMSO and 50 nl_ transferred to a low volume black 384 well micro titre plate using a Labcyte Echo 555. A Thermo Scientific Multidrop Combi was used to dispense 5 μΙ_ of 20 nM protein in an assay buffer of 50 mM HEPES, 150 mM NaCI, 5% glycerol, 1 mM DTT and 1 mM CHAPS, pH 7.4, and in the presence of 100 nM fluorescent ligand (~K d concentration for the interaction between BRD4 BD1 and ligand). After equilibrating for 30 mins in the dark at rt, the bromodomain protein :fluorescent ligand interaction was detected using TR-FRET following a 5 μΙ_ addition of 3 nM europium chelate labelled anti-6His antibody (Perkin Elmer, W1024, AD01 1 1 ) in assay buffer. Time resolved fluorescence (TRF) was then detected on a TRF laser equipped Perkin Elmer Envision multimode plate reader (excitation = 337 nm; emission 1 = 615 nm; emission 2 = 665 nm; dual wavelength bias dichroic = 400 nm, 630 nm). TR-FRET ratio was calculated using the following equation: Ratio = ((Acceptor fluorescence at 665 nm) / (Donor fluorescence at 615 nm)) * 1000. TR-FRET ratio data was normalised to high (DMSO) and low (compound control derivative of I-BET762) controls and IC 50 values determined for each of the compounds tested by fitting the fluorescence ratio data to a four parameter model: y = a + (( b - a) / ( 1 + ( 10 A x / 10 A c ) A d ) where 'a' is the minimum, 'b' is the Hill slope, 'c' is the IC 50 and 'd' is the maximum.

The compound of formula (IA) was tested in all of the BRPF1 , BRPF2, BRPF3, BRD4 BD1 , and BRD4 BD2 TR-FRET assays described above and were found to have a plC 50 as shown in the table below:-

NanoBRET assays.

HEK293 cells (8 x 10 5 ) were plated in each well of a 6-well plate and co-transfected with Histone H3.3-HaloTag (NM_002107) and NanoLuc-BRPF1 isoform 1 (P55201 -1 ) bromodomain amino acids 625-735 or isoform 2 (P55201 -2) bromodomain amino acids 625- 741 . Isoform 2 has an insertion S660 -> SEVTELD in the bromodomain. Twenty hours post- transfection cells were collected, washed with PBS, and exchanged into media containing phenol red-free DMEM and 4% FBS in the absence (control sample) or the presence

(experimental sample) of 100 nM NanoBRET 618 fluorescent ligand (Promega). Cell density was adjusted to 2 x 10 5 cells/mL and then re-plated in a 96-well assay white plate (Corning Costar #3917). Inhibitors were then added directly to media at final concentrations between 0-33 μΜ and the plates were incubated for 18 h at 37 °C in the presence of 5% C0 2 .

NanoBRET furimazine substrate (Promega) was added to both control and experimental samples at a final concentration of 10 μΜ. Readings were performed within 5 minutes using the CLARIOstar (BMG) equipped with 450/80 nm bandpass and 610 nm longpass filters with a 0.5 sec reading setting. A corrected BRET ratio was calculated and is defined as the ratio of the emission at 610 nm/450 nm for experimental samples (i.e. those treated with NanoBRET fluorescent ligand) subtracted by the emission at 610 nm/450 nm for control samples (not treated with NanoBRET fluorescent ligand). BRET ratios are expressed as milliBRET units (mBU), where 1 mBU corresponds to the corrected BRET ratio multiplied by 1000.

The compound of formula (IA) was tested in the BRPF1 isoform 1 , and isoform 2 assays described above and were found to have a plC 50 as shown in the table below:

Solubility CLND solubility measurement.

Solubility was determined by precipitation of 10 mM DMSO stock concentration to 5% DMSO pH7.4 phosphate buffered saline, with quantification by ChemiLuminescent Nitrogen Detection.

Results

Compound of Formula (IA): 140 micrograms/ml

Compound of Formula (IB): 134 micrograms/ml

Fasted State Simulated Intestinal Fluid (FaSSIF)

Compound of Formula (IA): >1000 micrograms/ml

References

Chung C,. et al, J. Med. Chem., 201 1 , 54, 3827-3838.