WO2016067012A1

WO2016067012A1 - Compounds as sirt2 inhibitors

Info

Publication number: WO2016067012A1
Application number: PCT/GB2015/053217
Authority: WO
Inventors: Matthew FUCHTER; Paolo DI FRUSCIA; Michael Sternberg; Chris Reynolds
Original assignee: Imperial Innovations Limited
Priority date: 2014-10-27
Filing date: 2015-10-27
Publication date: 2016-05-06
Also published as: GB201419102D0

Abstract

The invention provides compounds of formula (I) or a salt thereof, wherein R¹, R², R³, R⁴, R⁵ and R⁶are as defined in the specification. The invention also provides compositions comprising the compounds, and methods of using the compounds for the treatment of a disease in which inhibition of SIRT2 provides a therapeutic or prophylactic effect, for example cancers,metabolic disorders, inflammatory disorders,neurodegenerative disorders and central nervous system disorders.

Description

COMPOUNDS AS SIRT2 INHIBITORS

Field of Invention This application relates to compounds which have activity as inhibitors of SIRT2, and which are useful in the prevention or treatment of diseases such as cancer, metabolic disorders and neurodegenerative disorders, for example Parkinson's disease.

Background to the invention

Sirtuins (silent information regulator 2-related proteins) or class III HDACs, are members of the histone deacetylase family, sharing high sequence identity with the yeast Saccharomyces cerevisiae protein Sir2 (silent information regulator 2) and requiring NAD⁺ as the cofactor to affect deacetylation (Gregoretti, I. V., et al, Mol. Biol. 2004, 338, 17-31). The sirtuin family is broadly conserved from bacteria to humans and seven sirtuin isoforms, named SIRT 1-7, have been identified in humans. All SIRT proteins contain a conserved catalytic core domain comprised of approximately 275 amino acid residues with variable N- and C-termini. The seven isozymes differ in their substrate specificity, biological functions and cellular localisation: SIRTl, 6 and 7 principally localise in the nucleus, however SIRTl has also been found in the cytoplasm; SIRT2 is predominantly a cytoplasmic protein, but shuttles to the nucleus during mitosis; SIRT3, 4 and 5 are mitochondrial enzymes (Finkel, T., et al, R., Nature 2009, 460, 587-591).

In addition to the NAD-dependent deacetylation of ε-amino-acetylated lysine residues of target proteins by SIRTs, several of these enzymes have been reported to mediate other transformations. For example, SIRT4 and 6 have been shown to catalyse the ADP- ribosylation of protein substrates (Saunders, L. R., et al, Oncogene 2007, 26, 5489-5504.; Laurent, G., et al, Mol. Cell 2013, 50, 686-698.), and SIRT5 has significant desuccinylase activity (Du, J., et al, . Science 2011, 334, 806-809.; Fischer, F., et al, PLoS One 2012, 7, e45098, 1-9.).

The most studied sirtuin isoforms are SIRTl and SIRT2, which have been found to deacetylate a wide range of histone and non-histone proteins, therefore having a fundamental role in several physiological and pathological pathways (Michan, S., et al, Biochem. J. 2007, 404, 1-13; Milne, J. C, et al, Curr. Opin. Chem. Biol. 2008, 12, 11-17; Baur, J. A., et al, Nat. Rev. DrugDiscov. 2012, 11, 443-461). While SIRT2 has been shown to deacetylate histone H4/K16, its substrates are predominantly non-histone proteins. For example, it has been found to inhibit adipocyte differentiation by regulating FoxOl acetylation status, to deacetylate Fox03a in response to oxidative stress and caloric restriction, to deacetylate a- tubulin, and to play a role in p53 deacetylation. SIRT2 is overexpressed during mitosis, affecting the cell cycle and its activity has been found to be deregulated in a variety of cancers (Zhang, Y., et al, Biochem. Biophys. Res. Commun. 2009, 386, 729-733.; Li, Y, et al, Genes Cells 2011, 16, 34-45; Kim, H. S., et al, Cancer Cell 2011, 20, 487-499.), metabolic disorders (Luthi-Carter, R,., et al, Proc. Natl. Acad. Sci. U. S. A. 2010, 107, 7927-7932.; Jing, E., et al, Cell Metab. 2007, 6, 105-114.) and neurological disorders (Beirowski, B., et al, Proc. Natl. Acad. Sci. U. S. A. 2011, 108, E952-E961.; Halting, K., et al, ACS Chem. Biol. 2007, 2, 529-532.). Accordingly, small-molecule modulators of SIRT2 may be used as agents to treat SIRT2- dependent pathologies, and as tools to investigate and define the biological roles of SIRT2.

A variety of SIRT inhibitors, some with selectivity for SIRT2, have been discovered to date, as shown in Figure 1. These include the physiological inhibitor nicotinamide (1); the 2- hydroxy-naphthaldehyde derivatives sirtinol (2), cambinol and salermide (3); AGK2 (4); AK- 7 (5) and its analogous 3-(N-arylsulfamoyl)benzamide derivatives; the natural dilactone tanikolide dimer (6); splitomicin derivatives; suramin; NAD⁺ derivatives; 3'-phenethyloxy-2- anilinobenzamide analogues (7); 10, l l-dihydro-5H-dibenz[b,f]azepine derivative (8);

thieno[3,2-d]pyrimidine-6-carboxamides (9); thioacetylated pseudopeptides, and a variety of recently discovered inhibitors. However, there remains a need in the art for further compounds active as inhibitors of SIRT2.

Summary of the Invention In a first aspect, the invention provides a compound of formula (I), or a salt thereof,

A is -(CR⁹R¹⁰)m-; m is 0, 1, 2 or 3;

R¹ is selected from the group consisting of

Ci-6alkyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of -F, -OH, -CN, -OCi-4alkyl,

R⁷R⁸ and -OCF₃;

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF -OH, -OCi_-4alkyl, -OCF₃, - R⁷R⁸, -CN, and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and

3-10-membered heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF -OH, -OCi_-4alkyl, -OCF₃, -NR⁷R⁸, -CN, and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

and where m is 1, 2 or 3, R¹ may additionally be -OCi_-4alkyl, -CN, or -NHC(0)Ci_-4alkyl; B is -(CR^uR¹²)n- or -(CH2)_P-C(0)-(CH₂)_q-; n is 0, 1, 2 or 3; p and q are each independently 0, 1 or 2;

R² is selected from the group consisting of

3-10-membered carbocycle which is unsubstituted or substituted by

1, 2, or 3 substituents each independently selected from the group consisting of

halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃, -NR⁷R⁸, -CN; -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

phenyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from halogen, -OCH3 and -OH;

-CH₂-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH3 and -OH;

and -O-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH3 and -OH;

and 3-10-membered heterocycle which is unsubstituted or substituted by

halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF3; - R⁷R⁸; -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

phenyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from halogen, -OCH₃ and -OH;

-CH₂-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OC¾ and -OH;

and -O-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OC¾ and -OH;

R³ is selected from the group consisting of

hydrogen;

Ci-6alkyl which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of -F, -OH, -OCH₃, -OCF₃, R⁷R⁸ and -CN;

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi-4alkyl, -CN, -CF₃, NR⁷R⁸ and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and 3-10-membered heterocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi-4alkyl, -CN, -CF₃, R⁷R⁸ and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

R⁴ is hydrogen or -Ci-4alkyl; either R⁵ and R⁶ together are -CH2-CH2- so that together with the intervening atoms they form a 6-membered carbocycle, or R⁵ and R⁶ are each independently selected from the group consisting of H and -Ci-4alkyl; each R⁷ and R⁸ is independently selected from the group consisting of hydrogen and -C1-4- alkyl; and each R⁹, R¹⁰, R¹¹ and R¹² is independently selected from the group consisting of hydrogen, methyl and -CN; with the proviso that the compound is not 3-[(2-methoxy-l-naphthyl)methyl]-7-(3- pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof, or 7-[(4-fluorophenyl)methylamino]-3-(3-quinolylmethyl)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof.

Compounds of formula (I) have surprisingly been found to have activity as inhibitors of SIRT2. Example compounds of the invention have been found to be particularly potent inhibitors of SIRT2, as demonstrated by their low IC50 values. Example compounds of the invention have also surprisingly been found to be selective for inhibition of SIRT2 over other SIRT proteins i.e. SIRT1, SIRT3 and SIRT5.

The invention also provides a compound which is (7R)-3-[(2-methoxy-l-naphthyl)methyl]- 7-(3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one, or a salt thereof. The invention also provides a compound which is (7S)-3-[(2-methoxy-l-naphthyl)methyl]-7- (3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one, or a salt thereof.

The invention also provides a pharmaceutical composition which comprises:

(i) a compound of formula (Γ), or a salt thereof,

wherein: A is -(CR⁹R¹⁰)m-; m is 0, 1, 2 or 3;

R¹ is selected from the group consisting of

R⁷R⁸ and -OCF₃;

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3; -OH, -OCi_-4alkyl, -OCF₃, - R⁷R⁸, -CN, and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and

3-10-membered heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3; -OH, -OCi_-4alkyl, -OCF₃, -NR⁷R⁸, -CN, and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

and where m is 1, 2 or 3, R¹ may additionally be -OCi_-4alkyl, -CN, or -NHC(0)Ci_-4alkyl;

B is -(CR^uR¹²)n- or -(CH2)_P-C(0)-(CH₂)_q-; n is 0, 1, 2 or 3; p and q are each independently 0, 1 or 2; R² is selected from the group consisting of

3-10-membered carbocycle which is unsubstituted or substituted by

halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃, - R⁷R⁸, -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

and -O-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OC¾ and -OH; and 3-10-membered heterocycle which is unsubstituted or substituted by

halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃; - R⁷R⁸; -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

-CH₂-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH₃ and -OH;

and -O-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH₃ and -OH;

R³ is selected from the group consisting of hydrogen;

Ci-6alkyl which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of -F, -OH, -OCH3, -OCF3, R⁷R⁸ and -CN;

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi-4alkyl, -CN, -CF₃, NR⁷R⁸ and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and

3-10-membered heterocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi-4alkyl, -CN, -CF3, NR⁷R⁸ and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

R⁴ is hydrogen or -Ci-4alkyl; either R⁵ and R⁶ together are -CH2-CH2- so that together with the intervening atoms they form a 6-membered carbocycle, or R⁵ and R⁶ are each independently selected from the group consisting of H and -Ci-4alkyl; each R⁷ and R⁸ is independently selected from the group consisting of hydrogen and -C1-4- alkyl; and each R⁹, R¹⁰, R¹¹ and R¹² is independently selected from the group consisting of hydrogen, methyl and -CN; and

(ii) a pharmaceutically acceptable carrier.

The invention also provides

a compound of formula (I) or (Γ) as defined above, or a salt thereof;

or a pharmaceutical composition comprising a compound of formula (I) or (Γ) as defined above, or a salt thereof, and a pharmaceutically acceptable carrier;

for use as a medicament. The invention also provides use of a compound of formula (I) or (Γ) as defined above, or a salt thereof, for the manufacture of a medicament for the prevention or treatment of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect. The invention also provides a method of treating or preventing a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect in a mammal, which comprises administering to the mammal a therapeutically effective amount

of a compound of formula (I) or (Γ) as defined above, or a salt thereof,

or of a pharmaceutical composition comprising a compound of formula (I) or (Γ) as defined above, or a salt thereof, and a pharmaceutically acceptable carrier.

The invention also provides a kit of parts comprising:

(a) a first pharmaceutical composition comprising a compound of formula (I) or (Γ) as defined above, or a salt thereof, and a pharmaceutically acceptable carrier; and

(b) a second pharmaceutical composition comprising a further therapeutic agent and a pharmaceutically acceptable carrier.

Brief description of the drawings

Figure 1 shows the structures of some known SIRT inhibitors.

Figure 2 (a) and 2 (b) show concentration/inhibition curves for the compounds of Examples 1 and 7 against SIRTl, SIRT2, SIRT3 and SIRT5 in a fluorogenic assay.

Figure 3 shows concentration/inhibition curves for the compound of Example 1 against SIRTl and SIRT2, in a SIRT-Glo™ assay.

Figure 4 (a) shows SIRT2 activity against tubulin-K40 peptide at varying concentrations of the compound of Example 1 (empty circles 0 μΜ; filled triangles 1.25 μΜ; empty triangles 2.5 μΜ; filled squares 5 μΜ). Lines show the activity pattern for competition. Figure 4 (b) shows SIRT2 activity against NAD⁺ at varying concentrations of the compound of Example 1 (empty circles 0 μΜ; filled triangles 1.25 μΜ; empty triangles 2.5 μΜ; filled squares 5 μΜ). Lines show the activity pattern for non-competitive inhibition (upper graph) and mixed-type competition (lower graph).

Figure 5 (a) shows predicted binding of the compound of Example 1 (space-filling representation) at the active site of human SIRT2 (molecular surface representation, PDB ID: 1J8F). Figures 5 (b) and (c) show close-up views of the compound of Example 1 docked into the acetyl ated- substrate binding domain of SIRT2. Figure 5 (d) shows rigid superposition of SIRT1 (PDB ID: 4IG9), SIRT2 (PDB ID: 1J8F), SIRT3 (PDB ID: 3GLS) and SIRT5 (PDB ID: 2B4Y) crystal structures. The compound of Example 1 is displayed docked into the acetyl ated- substrate binding domain of SIRT2, and critical active site residues (stick representation) are displayed.

Figure 6 shows western blot data showing the levels of FOX03a, acetylated-a-tubulin and β- tubulin in harvested MCF-7 cells following treatment with the compound of Example 1 or a comparator compound (upper panel) and shows normalisation of the quantified acetylated-a- tubulin levels to ^-tubulin (lower panel).

Figure 7 shows the results of clonogenic assays in MCF-7 Cells: the upper panel shows representative images of colonies exposed to various concentrations of the compound of Example 1 and a comparator compound (0 μΜ; 0.5 μΜ; 5 μΜ; 12.5 μΜ, 25 μΜ) (crystal violet staining used); the lower panel shows the average cell proliferation (relative to control) of colonies exposed to various concentrations of the compound of Example 1 and a comparator compound (0 μΜ; 0.5 μΜ; 5 μΜ; 12.5 μΜ, 25 μΜ).

Figure 8 shows the effects of the compound of Example 1 in an in vitro model of

Parkinsonian cell death, in rat mescenscephalic dopaminergic neurons.

Figure 9 shows the results of an assay carried out to determine the ability of the compounds of Examples 1, 6 and 7 to produce H2O2 in the presence of 1 mM DTT via redox cycling.

Detailed description of the invention

The present invention provides compounds that are inhibitors of SIRT2. The terms "inhibitor of SIRT2" and "SIRT2 inhibitor" as used herein is intended to cover any moiety which binds to SIRT2 and inhibits its activity. The inhibitors may act as competitive inhibitors, or partial competitive inhibitors. Without being bound by any particular theory, the compounds of the present invention are believed to bind and inhibit SIRT2 via the acetylated-substrate pocket of SIRT2.

Definitions

The following definitions apply to the terms as used throughout this specification, unless otherwise limited in specific instances. As used herein, the term "alkyl " means both straight and branched chain saturated

hydrocarbon groups. Examples of alky l groups include methyl, ethyl, n-propyl, i so-propv , n- butyl, t-butyl, i-butyl, sec-butyl, pentyl and hexyl groups. Among unbranched alkyl groups, there are preferred methyl, ethyl, n-propyl, n-buty groups. Among branched alkyl groups, there may be mentioned t-butyl , i-butyl, I -ethyl propyl and 1 -ethylbutyl groups.

As used herein, the term "carbocyclyl " (or carbocycle) is intended to mean a carbon ring system, which may be saturated, partially unsaturated, or aromatic. The carbon ring system may be monocyclic or contain more than one ring (e.g. the ring system may be bicyclic). Examples of monocyclic saturated carbocycles include cyclopropyl, cyclobutyl, cy clopentyl, cyclohexyl, cycloheptyl, cyclooctyl . Examples of bicyclic saturated carbocycles include bicyclooctane, bicyclononane, bicyclodecane (decalin ) and bicyclooctane. A further example of a saturated carbocycle i s adamantane. Examples of monocyclic non- saturated carbocycles include cyclopentene and cyclohexene. Examples of aromatic carbocycles include phenyl and naphthyl . Further examples of bicyclic aromatic carbocycles include those in which one of the rings is aromatic and the other i s non-aromatic, for example tetrahydronaphthyl (tetralin) and indane.

As used herein, the term "cycloalkyl " means a saturated carbon ring system. A cycloalkyl group can be monocyclic or bicyclic. A bicyclic group may, for example, be fused or bridged. Examples of monocyclic cycloalkyl groups include cyclopropyl, cyclobutyl and cyclopentyl . Other examples of monocyclic cycloalkyl groups are cyclohexyl, cycloheptyl and cyclooctyl . Examples of bicyclic cycloalkyl groups include bicyclo [2.2. 1 ]hept-2-yl . As used herein, the term "halogen" or "halo" means fluorine, chlorine, bromine or iodine.

As used herein, the term "heterocyclvl" (or heterocycle) means an aromatic or a non-aromatic cyclic group of carbon atoms wherein from one to four of the carbon atoms i s/are replaced by one or more heteroatoms independently selected from nitrogen, oxygen or sulfur. A heterocyclvl (or heterocycle) group may, for example, be monocyclic or bicyclic. In a bicyclic heterocyclvl (or heterocycle) group there may be one or more heteroatoms in each ring, or only in one of the rings. A heteroatom may be S, O or N. Examples of monocyclic non-aromatic heterocyclyl (or heterocycle) include aziridinyl, azetidinyl, pyrrol idinyl, imidazolidinyl, pyrazolidinyl, piperidinyl, piperazinyl,

t et ra h yd r ofu r a n y 1 , tetrahydropyranyl, morpholinyl, thiomorpholinyl and azepanyl . Examples of monocyclic aromatic heterocyclyl (or heterocycle) groups include furanyl , thienyl, pyrrol yl, oxazolyl, thiazolyl, imidazolyl, oxadiazolyl, thiadiazolyl, pyridyl, triazolyl, triazinyl, tetrazolyl, pyridazyl, isothiazolyl, isoxazolyl, pyrazinyl, pyrazolyl and pyrimidinyl. Examples of bi cyclic aromatic heterocyclyl groups ( or heterocycle) include quinoxalinyl, quinazolinyl, pyridopyrazinyl, benzoxazolyl, benzothiophenyl, benzimidazolyl,

naphthyridinyl, quinolinyl, benzo furanyl, indolyl, benzothiazolyl, ox azo 1 y 1 [4, 5 -b ] py r i di y 1 , pyridopyrimidinyl, isoquinolinyl and benzodroxazole. Further examples of bi cyclic aromatic heterocyclyl groups include those in which one of the rings is aromatic and the other is non- aromatic, such as di h drobenzo furanyl , indanyl, indolinyl, isoindolinyl,

t et ra h y droi soq u i n ol i ny 1 , tetrahydroquinolyl and benzoazepanyl .

The compounds of the invention may contain chiral (asymmetric) centers. The molecule as a whole may be chiral . Unless specified otherwise, individual stereoisomers (enantiomers and diastereoi somers) and mixtures of these are within the scope of the present invention. For the avoidance of doubt, an embodiment or preferred aspect of any one feature of the compound of the invention may be combined with any embodiment or preferred aspect of another feature of the compound of the invention to create a further embodiment. For the avoidance of doubt, any embodiment or preferred aspect of any one feature or combination of embodiments or features of the compounds of the invention also relates to salts of the compounds.

In one embodiment, the compound has the formula (IA):

(ΪΑ)

wherein A, B, m, n, p, q, R¹, R², R⁴, R⁵, R⁶, R⁷,R⁸, R⁹, R¹⁰, R^{1 1} and R¹² are as defined above for the compound of formula (I) or (Γ).

In one preferred embodiment, the compound has the formula (IB):

wherein A, B, m, n, p, q, R¹, R\ R³, R⁴, R⁷,R⁸, R⁹, R¹⁰, R" and R¹² are as defined for the compound of formula (I) or (Γ) above.

More preferably, the compound has the formula (IC):

wherein A, B, m, n, p, q, R¹, R², R⁴, R⁷,R⁸, R⁹, R¹⁰, R^u and R¹² are as defined for the compound of formula (I) or ( I ) above. In one preferred embodiment of the compound of formula ( I ) or ( 1 ), R ' is selected from the group consisting of hydrogen, and phenyl which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of -F, -CI, -OCH3, -CN, -CH3, and -CF3. More preferably R³ is hydrogen or unsubstituted phenyl. Most preferably R³ is hydrogen.

In one preferred embodiment of the compound of formula (I) or (Γ), R⁴ is hydrogen.

In one preferred embodiment of the compound of formula (I) or (Γ), R⁵ and R⁶ are each independently selected from the group consisting of hydrogen and methyl, or R³ and R⁶ together are -CH2-CH2- so that together with the intervening atoms they form a 6-membered carbocycle. Most preferably R⁵ and R⁶ together are -CH2-CH2- so that together with the intervening atoms they form a 6-membered carbocycle, as is the case for the compounds of formula (IB) and (IC) shown above.

In one particularly preferred embodiment the compound has the formula (ID):

wherein A, B, m, n, p, q, R¹, R², R⁷,R⁸, R⁹, R¹⁰, R¹¹ and R¹² are as defined for the compound of formula (I) or (Γ) above.

In one preferred embodiment of the compound of formula (I) or (I ), A is -CH2- or -CH₂CH₂- ; more preferably A is -CH₂-.

In one preferred embodiment of the compound of formula ( I ) or (Γ), R⁹ is hydrogen, methyl or -CN, and each of R¹⁰, R ^{1 1} and R¹² is hydrogen. More preferably each R⁹, R¹⁰, R ^{1 1} and R¹² is hydrogen.

In one preferred embodiment of the compound of formula (I) or (Γ), R¹ is C u.alkyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of -F, -OH, -CN, -OCi-4alkyl, R⁷R⁸ and -OCF3; more preferably R¹ is unsubstituted Ci-6alkyl; yet more preferably R¹ is unsubstituted C4 alkyl; still more preferably R¹ is t-butyl.

In one preferred embodiment of the compound of formula (I) or (Γ), R¹ is a 3-10 membered carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3> -OH, -OCi_-4alkyl, -OCF3, - R⁷R⁸, -CN, and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; more preferably R¹ is a 6-10 membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF3; still more preferably R¹ is a 6-10 membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -C1-4 alkyl, -CF₃,

-OCi-4alkyl and -OCF₃; yet more preferably R¹ is phenyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OCi-4alkyl, -CN, -Ci-4alkyl, -OCF₃ and -CF₃; still more preferably R¹ is phenyl which is unsubstituted or substituted by 1 or 2 substituents each independently selected from the group consisting of -F, -OCH₃ and -Me. In one embodiment R¹ is indanyl.

In one preferred embodiment of the compound of formula (I) or (Γ), R¹ is a 3-10-membered heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3, -OH, -OCi_-4alkyl, -OCF₃, -NR⁷R⁸, -CN, and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; more preferably R¹ is a 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3, -OCi_-4alkyl, -OCF₃, -CN and -Ci_-4alkyl; still more preferably R¹ is a

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3;

-OCi-4alkyl, -OCF₃, and -Ci-4alkyl; yet more preferably R¹ is a 5-6-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OCi-4alkyl, -Ci-4alkyl, -CF₃ and -OCF₃; still more preferably R¹ is an 5-6-membered aromatic heterocycle which is unsubstituted or substituted by -F, -OCH₃ or Me; yet more preferably R¹ is thiophene or pyridine; still more preferably R¹ is 2-thiophenyl or 3-pyridinyl. In one preferred embodiment of the compound of formula (I) or (1 ), R¹ is a 3-10-membered saturated heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi-4alkyl, -OCF3, - R⁷R⁸, -CN, and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups. In one preferred embodiment of the compound of formula (I) or (Γ), A is -CH2-, and R¹ is unsubstituted -Ci-6alkyl; more preferably A is -CH₂-, and R¹ is unsubstituted C4 alkyl; still more preferably A is -GHz- and R¹ is t-butyl.

In one preferred embodiment of the compound of formula (I) or (Γ), A is -CH2- and R¹ is a 6- 10 membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -C1-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF3; more preferably A is -CH₂- and R¹ is a 6-10 membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -C1-4 alkyl, -CF₃, -OCi- 4alkyl and -OCF₃; yet more preferably A is -CH₂- and R¹ is phenyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OCi-4alkyl, -CN, -Ci-4alkyl, -OCF₃ and -CF₃; still more preferably A is -CH₂- and R¹ is phenyl which is unsubstituted or substituted by 1 or 2 substituents each independently selected from the group consisting of -F, -OCH₃ and -Me. In one embodiment m is 0 (i.e. A is bond) and R¹ is indanyl. In one preferred embodiment of the compound of formula (I) or (Γ), A is -CH₂- and R¹ is a 5- 6-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH,

-OCi_-4alkyl, -Ci_-4alkyl, -CF₃, -CN and -OCF₃; more preferably A is -CH₂- and R¹ is a 5-6- membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3

substituents each independently selected from the group consisting of halogen, -OCi-4alkyl, -Ci-4alkyl, -CF₃, and -OCF₃; yet more preferably A is -CH₂- and R¹ is an 5-6-membered aromatic heterocycle which is unsubstituted or substituted by -F, -OCH₃ or Me; still more preferably A is -CH₂- and R¹ is thiophene or pyridine; yet more preferably A is -CH₂- and R¹ is 2-thiophenyl or 3-pyridinyl. In one embodiment of the compound of formula (I) or (Γ), each R and each R⁸ is -Ci-4alkyl. In one embodiment each R⁷ and each R⁸ is -CH₃. In one preferred embodiment of the compound of formula (I) or (Γ), B is -(CH]),_r and n is 0, 1, 2 or 3; more preferably B is -(CH₂)n- and n is 1 or 2; still more preferably B is -CH₂-.

In one embodiment of the compound of formula (I) or (Γ), R² is a 3-10-membered heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃, - R⁷R⁸, -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; phenyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from halogen, -OCH₃ and -OH; -CH₂-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH₃ and -OH; and

-O-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH₃ and -OH.

Preferably R² is a 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3> -OCi_-4alkyl, -OCF₃, -CN and unsubstituted -Ci-₄alkyl. More preferably R² is a 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3;

-OCi-4alkyl, -OCF₃, and unsubstituted -Ci-4alkyl; yet more preferably R² is quinoline; still more preferably R² is 3-quinolinyl.

In one preferred embodiment of the compound of formula (I) or (Γ), R² is a 3-10-membered carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃, -NR⁷R⁸, -CN; -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; phenyl which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from halogen, -OCH₃ and -OH; -CH2-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH3 and -OH; and

-O-phenyl which is unsubstituted or substituted on the phenyl moiety by 1, 2, or 3 substituents each independently selected from halogen, -OCH3 and -OH. More preferably R² is a 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF₃, -OCi-4alkyl, -OCF3, -CN and unsubstituted -Ci-4alkyl; yet more preferably R² is a 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF₃, -OCi-4alkyl, -OCF3, and unsubstituted -Ci-4alkyl; still more preferably R² is

naphthalene which is unsubstituted or substituted by -OCi-4alkyl; yet more preferably R² is a 2-methoxynapthalen-l-yl group.

In one preferred embodiment of the compound of formula (I) or (I ) B is -(CH2)-, and R² is a

5- 10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3,

-OCi-4alkyl, -OCF3, -CN and unsubstituted -Ci-4alkyl; more preferably B is -(CH2)-, and R² is a 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3, -OCi-4alkyl, -OCF3 and unsubstituted -Ci-4alkyl; yet more preferably B is -(CH₂)-, and R² is quinoline; still more preferably B is -(CH₂)-, and R² is 3-quinolinyl.

In one preferred embodiment of the compound of formula (I) or (Γ) B is -(CH2)-, and R² is a

6- 10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3, -OCi-4alkyl, -OCF3, -CN and unsubstituted -Ci-4alkyl; more preferably B is -(CH₂)-, and R² is a 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3, -OCi-4alkyl, -OCF3, and unsubstituted -Ci-4alkyl; yet more preferably B is -(CH₂)-, and R² is naphthalene which is unsubstituted or substituted by

yet more preferably B is -(CH₂)-, and R² is a 2-methoxynapthalen-l-yl group. In one particularly preferred embodiment of the compound of formula (I) or (Γ), the compound has the formula (ID):

wherein A is -(CH₂)-; R¹ is selected from the group consisting of unsubstituted -Ci-6alkyl;

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, -CN,-OCi_-4alkyl and -OCF₃; and

5- 10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, -CN,-OCi_-4alkyl and -OCF₃;

B is -(CH₂)-; and

R² is selected from the group consisting of

6- 10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF₃, -OCi- alkyl, -OCF₃, -CN and unsubstituted -Ci- alkyl; and

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF₃, -OCi- alkyl, -OCF₃, -CN and unsubstituted -Ci- alkyl.

In one particularly preferred embodiment of the compound of formula (I) or (Γ), the compound has the formula (ID):

A is -(CH2)-; R¹ is unsubstituted -Ci-6alkyl; B is -(CH₂)-; and

R² is an 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, 3 substituents each independently selected from the group consisting of halogen, -OH, -CF OCi_-4alkyl, -OCF3, -CN, and unsubstituted -Ci-₄alkyl.

A is -(CH₂)-;

R¹ is a 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, CN, -OCi_-4alkyl and -OCF3;

B is -(CH₂)-; and

R² is selected from the group consisting of 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3> -OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl; and

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH,

-CF_3> -OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl.

A is -(CH₂)-;

R¹ is an 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF3;

B is -(CH₂)-; and

R² is selected from the group consisting of

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF₃, -OCi- alkyl, -OCF₃, -CN and unsubstituted -Ci- alkyl; and

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF₃, -OCi- alkyl, -OCF₃, -CN and unsubstituted -Ci- alkyl. In one particularly preferred embodiment of the compound of formula (I) or (Γ), the compound has the formula (ID):

wherein A is -(CH2)-; R¹ is selected from the group consisting of unsubstituted -Ci-6alkyl;

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃; and

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃;

B is -(CH₂)-; and

R² is an 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3; -OH, -OCi- alkyl, -OCF₃, -CN and unsubstituted -Ci- alkyl.

wherein A is -(CH₂)-;

R¹ is selected from the group consisting of unsubstituted -Ci-6alkyl;

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, -OCi_-4alkyl, -CN and -OCF₃; and

-Ci_-4 alkyl, -CF₃, -OCi_-4alkyl, -CN and -OCF₃;

B is -(CH₂)-; and

R² is an 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3; -OCi- alkyl, -OCF₃, -CN and unsubstituted -Ci- alkyl.

wherein A is -(CH₂)-;

R¹ is selected from the group consisting of unsubstituted-C4alkyl, unsubstituted thiophene, unsubstituted pyridine, or phenyl which is unsubstituted or substituted by 1 or 2 substituents each independently selected from the group consisting of -F, -OCH3 and -CH₃;

B is -(CH₂)-; and

R² is quinoline or naphthalene which is unsubstituted or substituted by by -OCH3.

In one embodiment of the compound of formula (I) or (Γ), the SIRT2 inhibitor has the formula (I A)

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF3; and

B is -(CH₂)-;

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3> -OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl.

R⁴ is hydrogen; and

R³ and R⁶ are each independently selected from the group consisting of hydrogen and Ci-₄ alkyl.

In one embodiment of the compound of formula (I) or (Γ), the compound has the formula (IA)

(IA) wherein A is -(CH2)-; R¹ is selected from the group consisting of unsubstituted -Ci-6alkyl;

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CM alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF3; and

5-10-membered aromatic heterocycle which is unsubstituted or substituted by, 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CM alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃;

B is -(CH₂)-; R² is an 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3, -OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl;

R⁴ is hydrogen; and

R⁵ and R⁶ are each independently selected from the group consisting of hydrogen and Ci-4 alkyl.

In one embodiment of the compound of formula (I) or (I ), the compound has the formula (IB)

unsubstituted -Ci-6alkyl;

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF3; and

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CM alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃;

B is -(CH₂)-;

R² is selected from the group consisting of 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, OH, -CF_3> -OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl; and

5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, OH, -CF_3> -OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl;

R ^' is hydrogen or unsubstituted phenyl; and

R⁴ is hydrogen or Ci-₄ alkyl.

In one embodiment of the compound of formula (I) or (F), the compound has the formula (IB)

unsubstituted -Ci-6alkyl;

B is -(CH₂)-; R² is an 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, 3 substituents each independently selected from the group consisting of halogen, -OH, -CF OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl;

R³ is hydrogen or unsubstituted phenyl; and

R⁴ is hydrogen.

In one preferred embodiment of the compound of formula (I) or (Γ), the compound has the formula (IC)

wherein A is -(CH2)-;

R¹ is selected from the group consisting of unsubstituted -Ci-6alkyl;

B is -(CH₂)-;

-CF3, -OCi_-4alkyl, -OCF3, -CN and unsubstituted -Ci_-4alkyl; and

R⁴ is hydrogen or Ci-₄ alkyl .

wherein A is -(CH2)-;

R¹ is selected from the group consisting of unsubstituted -Ci-6alkyl;

6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH -Ci_-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF3; and 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH -Ci_-4 alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃;

B is -(CH₂)-; R² is an 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -CF_3, - OCi-4alkyl, -OCF3, -CN and unsubstituted -Ci-4alkyl; and

R⁴ is hydrogen.

In one embodiment, the compound is a compound of formula (I) or (Γ) as defined above, with the proviso that RHs not a 3-pyridyl group and A is not -CH2-. In another embodiment, the compound is a compound of formula (I) or (Γ) as defined above, with the proviso that RHs not a 4-fluorophenyl group and A is not -CH₂.

In one embodiment, the compound is a compound of formula (I) or (Γ) as defined above, with the proviso that R² is not a 3-quinolinyl group and B is not -CH₂-. In another embodiment, the compound is a compound of formula (I) or (Γ) as defined above, with the proviso that R² is not a 2-methoxy-l-napthyl group and B is not -CH₂-.

In one particularly preferred embodiment of the compound of formula (I) or (Γ), the compound is any one of the following compounds:

7-(benzylamino)-3-[(2-methoxy-l-naphthyl)methyl]-5,6,7,8-tetrahydrobenzothiopheno[2,3- d]pyrimidin-4-one; 3-[(2-methoxy-l-naphthyl)methyl]-7-(o-tolylmethylamino)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one;

3-[(2-methoxy-l-naphthyl)methyl]-7-(2-thienylmethylamino)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one;

7-[(3-fluorophenyl)methylamino]-3-[(2-methoxy-l-naphthyl)methyl]-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

3-[(2-methoxy-l-naphthyl)methyl]-7-[(3-methoxyphenyl)methylamino]-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one; and

7-(2,2-dimethylpropylamino)-3-[(2-methoxy-l-naphthyl)methyl]-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one; or a salt thereof. The compounds 3-[(2-methoxy-l-naphthyl)methyl]-7-(3-pyridylmethylamino)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one and 7-[(4-fluorophenyl)methylamino]-3-(3 quinolylmethyl)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof are commercially available as an undefined mixture of optical isomers. However, to the best of the inventors' knowledge, no information is available regarding the properties of those compounds, and the individual enantiomers of the compounds or salts thereof have not been made available to the public.

Accordingly, the present invention does not encompass 3-[(2-methoxy-l-naphthyl)methyl]-7 (3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one as an undefined mixture of optical isomers, or a salt thereof, in itself. The present invention also does not encompass 7-[(4-fluorophenyl)methylamino]-3-(3-quinolylmethyl)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one as an undefined mixture of optical isomers, or a salt thereof, in itself.

In one embodiment, the compound of the invention is not racemic 3-[(2-methoxy-l- naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3- d]pyrimidin-4-one or a salt thereof, or racemic 7-[(4-fluorophenyl)methylamino]-3-(3- quinolylmethyl)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof.

In one particularly preferred embodiment the compound is (7R)-3-[(2-methoxy-l- naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3- d]pyrimidin-4-one, or a salt thereof.

In one particularly preferred embodiment the compound is (7S)-3-[(2-methoxy-l- naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3- d]pyrimidin-4-one, or a salt thereof.

In one particularly preferred embodiment the compound is (+)-3-[(2-methoxy-l- naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3- d]pyrimidin-4-one, or a salt thereof.

In one particularly preferred embodiment the compound is (-)-3-[(2-methoxy-l- naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3- d]pyrimidin-4-one, or a salt thereof.

In one embodiment the compound is (7R)-7-[(4-fluorophenyl)methylamino]-3-(3- quinolylmethyl)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one, or a salt thereof. In one embodiment the compound is (7S)-7-[(4-fluorophenyl)methylamino]-3-(3- quinolylmethyl)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one, or a salt thereof.

In one embodiment the compound is (+)-7-[(4-fluorophenyl)methylamino]-3-(3- quinolylmethyl)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one, or a salt thereof. In one embodiment the compound is (-)-7-[(4-fluorophenyl)methylamino]-3-(3- quinolylmethyl)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one, or a salt thereof.

In one preferred embodiment of the compound of formula (I) or (Γ), the compound is any one of the following compounds, or a salt thereof:



The compound of the invention may be in the form of a salt, e.g. a pharmaceutically acceptable salt. Salts of compounds of the invention which are suitable for use in medicine are those wherein a counter-ion is pharmaceutically acceptable. However, salts having non- pharmaceutically acceptable counter-ions are within the scope of the present invention, for example, for use as intermediates in the preparation of the compounds of the invention and their pharmaceutically acceptable salts.

Suitable salts according to the invention include those formed with organic or inorganic acids. In particular, suitable salts formed with acids according to the invention include those formed with mineral acids, strong organic carboxylic acids, such as alkanecarboxylic acids of 1 to 4 carbon atoms which are unsubstituted or substituted, for example, by one or more halogen, such as saturated or unsaturated dicarboxylic acids, such as hydroxy carboxylic acids, such as amino acids, or with organic sulfonic acids, such as (C_rC₄)-alkyl- or aryl-sulfonic acids which are unsubstituted or substituted, for example by one or more halogen. Pharmaceutically acceptable acid addition salts include those formed from hydrochloric, hydrobromic, sulphuric, nitric, citric, tartaric, acetic, phosphoric, lactic, pyruvic, acetic, trifluoroacetic, succinic, perchloric, fumaric, maleic, glycolic, lactic, salicylic, oxaloacetic, methanesulfonic, ethanesulfonic, p-toluenesulfonic, formic, benzoic, malonic, naphthalene-2-sulfonic, benzenesulfonic, isethionic, ascorbic, malic, phthalic, aspartic, and glutamic acids, lysine and arginine. Other acids, which may or may not in themselves be pharmaceutically acceptable, may be useful as intermediates in obtaining the compounds of the invention and their pharmaceutical acceptable acid addition salts. Those skilled in the art of organic chemistry will appreciate 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". Solvates, such as hydrates, exist when the drug substance incorporates solvent, such as water, in the crystal lattice in either stoichiometric or non-stoichiometric amounts. Drug substances are routinely screened for the existence of hydrates since these may be encountered at any stage of the drug manufacturing process or upon storage of the drug substance or dosage form. Solvates are described in S. Byrn et al, Pharmaceutical Research, 1995. 12(7): p. 954-954, and Water-Insoluble Drug Formulation, 2^nd ed. R. Liu, CRC Press, page 553, which are incorporated herein by reference.

Accordingly, it will be understood by the skilled person that the compounds of the invention may therefore be present in the form of solvates. Solvates of compounds of the invention which are suitable for use in medicine are those wherein the associated solvent is

pharmaceutically acceptable. For example, a hydrate is an example of a pharmaceutically acceptable solvate. However, solvates having non-pharmaceutically acceptable associated solvents may find use as intermediates in the preparation of the compounds according to the invention.

As mentioned above, the compounds of the invention have activity as inhibitors of SIRT2. Preferably the compound of the invention has an IC50 against SIRT2 of less than 100 μΜ. Many of the example compounds have been found to be potent inhibitors of SIRT2, and more preferably the compound of the invention has an IC50 against SIRT2 of less than 10 μΜ; still more preferably less than 5 μΜ; yet more preferably less than 1 μΜ.

The compounds of the invention find use in the treatment or prevention of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect. The compounds may be administered in the form of a pharmaceutical composition comprising the compound of the invention and a pharmaceutically acceptable carrier. Accordingly, the invention also provides a pharmaceutical composition comprising (i) a compound of formula (I) or (Γ) as defined above, or a salt thereof; and (ii) a pharmaceutically acceptable carrier.

The invention also provides a compound of formula (I) or (Γ) as defined above or a salt thereof, or a pharmaceutical composition comprising a compound of formula (I) or (Γ) as defined above or a salt thereof, and a pharmaceutically acceptable carrier, for use as a medicament. The compound of formula (I) or (Γ) as defined above or pharmaceutical composition comprising the compound of formula (I) or (Γ) as defined above find use in the prevention or treatment of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect, for example a cancer, metabolic disorder, inflammatory disorder, neurodegenerative disorder or a central nervous system disorder. In one preferred embodiment, the disease or disorder is selected from the group consisting of breast cancer, hepatocellular carcinoma, cervical cancer, liver cancer, brain cancer, kidney cancer, acute myeloid leukaemia, prostate cancer, pancreatic cancer, neuroblastoma, type II diabetes, prediabetes, insulin resistance syndrome, high blood pressure, abnormal cholesterol levels, polycystic ovary syndrome, metabolic syndrome, cardiovascular disease, vascular disease, hypercholesterolemia, obesity, dementia, Alzheimer's disease, Parkinson's disease and Huntington's disease. In one preferred embodiment the disease or disorder is selected from the group consisting of dementia, Alzheimer's disease, Parkinson's disease and Huntington's disease, more preferably Parkinson's disease. In another preferred embodiment, the disease or disorder is selected from the group consisting of breast cancer, hepatocellular carcinoma, cervical cancer, liver cancer, brain cancer, kidney cancer, acute myeloid leukaemia, prostate cancer, pancreatic cancer and neuroblastoma. In another preferred embodiment, the disease or disorder is selected from the group consisting of type II diabetes, pre-diabetes, insulin resistance syndrome, high blood pressure, abnormal cholesterol levels, polycystic ovary syndrome, metabolic syndrome, cardiovascular disease, vascular disease,

hypercholesterolemia and obesity.

The invention also provides a method for the treatment or prophylaxis of a disease or disorder in a subject in which inhibition of SIRT2 provides a therapeutic or prophylactic effect in a mammal, which comprises administering to the mammal a therapeutically effective amount of a compound of formula (I) or (Γ) as defined above or a salt thereof, or a pharmaceutical composition comprising a compound of formula (I) or (Γ) as defined above and a

pharmaceutically acceptable carrier. Preferences for diseases/disorders are the same as those listed above.

The invention also provides use of a compound of formula (I) or (Γ) as defined above or a salt thereof, for the manufacture of a medicament for the treatment or prophylaxis of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect. Preferences for diseases/disorders are the same as those listed above.

Preferred compounds of the invention are those which are selective for the SIRT2 enzyme over one or more other sirtuins (for example SIRT1, SIRT3 and/or SIRT5). For example, use of a compound of the invention that is a selective SIRT2 inhibitor may result in fewer side effects compared with use of a less selective compound. In one preferred embodiment, the compound of the invention has at least 5-fold, more preferably at least 10-fold, still more preferably at least 30-fold selectivity for SIRT2 over at least one of SIRT1, SIRT3 and/or SIRT5 (e.g. the compound inhibits SIRT2 with an IC50 value which is 5-fold, 10-fold, or 30- fold lower than the IC50 value for another sirtuin). In one preferred embodiment, the compound of the invention has at least 5-fold, more preferably at least 10-fold, still more preferably at least 30-fold selectivity for SIRT2 over each of SIRT1, SIRT3 and SIRT5.

The amount of active ingredient which is required to achieve a therapeutic effect will, of course, vary with the particular compound, the route of administration, the subject under treatment, including the type, species, age, weight, sex, and medical condition of the subject and the renal and hepatic function of the subject, and the particular disorder or disease being treated, as well as its severity. An ordinarily ski lled physician, veterinarian or clinician can readily determine and prescribe the effective amount of the drug required to prevent, counter or arrest the progress of the condition.

Oral dosages of the present invention, when used for the indicated effects, will range between about 0.01 mg per kg of body weight per day (mg/kg/day) to about 100 mg/kg/day, preferably 0.01 mg per kg of body weight per day (mg/kg/day) to 10 mg/kg/day, and most preferably 0. 1 to 5.0 mg/kg/day, for adult humans. For oral administration, the compositions are preferably provided in the form of tablets or other forms of presentation provided in discrete units containing 0.01 , 0.05, 0.1 , 0.5, 1.0, 2.5, 5.0, 10.0, 15.0, 25.0, 50.0, 100, and 500 milligrams of the active ingredient for the symptomatic adjustment of the dosage to the patient to be treated. A medicament typically contains from about 0.01 mg to about 500 mg of the active ingredient, preferably from about 1 mg to about 100 mg of active ingredient. Intravenously, the most preferred doses will range from about 0.1 to about 10 mg/kg/minute during a constant rate infusion. Compounds of the present invention may be administered in a single daily dose, or the total daily dosage may be administered in divided doses of two, three or four times daily. Compounds of the present invention may be administered in intranasal form via topical use of suitable intranasal vehicles, or via transdermal routes, using those forms of transdermal skin patches well known to those of ordinary skill in the art. To be administered in the form of a transdermal delivery system, the dosage administration will, of course, be continuous rather than intermittent throughout the dosage regimen.

While it is possible for the active ingredient to be administered alone, as mentioned above the active ingredient may be present in a pharmaceutical formulation or composition. Accordingly, the invention provides a pharmaceutical composition comprising (i) a compound of formula (I) or (Γ) or a salt thereof; and (ii) a pharmaceutically acceptabl e carrier. Pharmaceutically acceptable diluents, excipients and carriers are collectively referred to herein as "carrier" materials. Pharmaceutical compositions of the invention may take the form of a pharmaceutical formulation as described below.

The pharmaceutical formulations according to the inv ention include those suitable for oral , parenteral ( including subcutaneous, intradermal, intramuscular, intravenous [bolus or infusion], and intraarticular), inhalation (including fine particle dusts or mists which may be generated by means of various types of metered dose pressurized aerosols), nebulizers or insufflators, rectal, intraperitoneal and topical (including dermal, buccal, sublingual, and intraocular) admini stration, although the most suitable route may depend upon, for example, the condition and disorder of the recipient. The formulations may conveniently be presented in unit dosage form and may be prepared by any of the methods well known in the art of pharmacy. All methods include the step of bringing the active ingredient into association with the carrier which constitutes one or more accessory ingredients. In general the formulations are prepared by uniformly and intimately bringing into association the active ingredient with liquid carriers or finely divided solid carriers or both and then, if necessary, shaping the product into the desired formulation.

Formulations of the present invention suitable for oral administration may be presented as discrete units such as capsules, cachets, pills or tablets each containing a predetermined amount of the active ingredient; as a powder or granules; as a solution or a suspension in an aqueous liquid or a non-aqueous liquid, for example as elixirs, tinctures, suspensions or syrups; or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion. The active ingredient may al o be presented as a bolus, electuary or paste.

A tablet may be made by compression or moulding, optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing in a suitable machine the active ingredient in a free-flowing form such as a powder or granules, optionally mixed with a binder, lubricant, inert diluent, lubricating, surface active or dispersing agent. Moulded tablets may be made by moulding in a suitable machine a mixture of the powdered compound moistened w ith an inert liquid diluent. The tablets may optionally be coated or scored and may be formulated so as to provide slow or controlled release of the active ingredient therein. The compounds of the present invention can, for example, be admini stered in a form suitable for immediate release or extended release. Immediate release or extended release can be achieved by the use of suitable pharmaceutical compositions comprising the compounds of the present invention, or, particularly in the case of extended release, by the use of devices such as subcutaneous implants or osmotic pumps. The compounds of the present invention may al so be administered liposomallv.

Exemplary compositions for oral admi ni stration include suspensions which can contain, for example, microcrystalline cellulose for imparting bulk, alginic acid or sodium alginate as a suspending agent, methylcellulose as a viscosity enhancer, and sweeteners or flavoring agents such as those known in the art; and immediate release tablets which can contain, for example, microcrystalline cellulose, dicalcium phosphate, starch, magnesium stearate, calcium sulfate, sorbitol, glucose and/or lactose and/or other excipients, binders, extenders, disintegrants, diluents and lubricants such as those known in the art. 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, carboxy methyl eel 1 ul ose, polyethylene glycol, axes and the like. Disintegrators include without limitation starch, methylcellulose, agar, bentonite, xanthan gum and the like. The compounds according to the invention can also be delivered through the oral cavity by sublingual and/or buccal administration. Molded tablets, compressed tablets or freeze-dried tablets are exemplary forms which may be used. Exemplary compositions include those formulating the present compounds with fast dissolving diluents such as mannitol, lactose, sucrose and/or cyclodextrins. Al so included in such formulations may be high molecular weight excipients such as celluloses (avicel ) or polyethylene glycols (PEG). Such formulations can also include an excipient to aid mucosal adhesion such as hydroxy propyl cellulose (FfPC), hydroxy propyl methyl cellulose (HPMC), sodium carboxy methyl cellulose (SCMC), maleic anhydride copolymer (e g., Gantrez), and agents to control release such as polyacrylic copolymer (e.g. Carbopol 934). Lubricants, glidants, flavors, coloring agents and stabilizers may also be added for ease of fabrication and use. Lubricants used in these dosage forms include sodium oleate, sodium stearate, magnesium stearate, sodium benzoate, sodium acetate, sodium chloride and the like. For oral admini stration in liquid form, the oral drug components can be combined with any oral, nontoxic, pharmaceutically acceptable inert carrier such as ethanol, glycerol, water, and the like. The compounds of the present invention 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,

1,2-dipalmitoylphosphatidylcholine, phosphatidyl ethanolamine (cephaline), or

phosphatidylcholine (lecithin).

Formulations for parenteral administration include aqueous and non-aqueous sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose containers, for example sealed ampoules and vials, and may be stored in a freeze- dried (lyophilised) condition requiring only the addition of the sterile liquid carrier, for example saline or water- for-i n j ecti on ,

immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the kind previously described.

Exemplary compositions for parenteral administration include injectable solutions or suspensions w hich can contain, for example, suitable non-toxic, parenterally acceptable diluents or solvents, such as mannitol, 1,3-butanediol, water. Ringer' s solution, an i otonic sodium chloride solution, or other suitable dispersing or wetting and suspending agents, including synthetic mono- or digl cerides, and fatty acids, including oleic acid, or

Cremaphor.

Exemplary compositions for nasal, aerosol or inhalation administration include solutions in saline, which can contain, for example, benzyl alcohol or other suitable preservatives, absorption promoters to enhance bioavailability, and/or other sol ubili zing or di spersing agents such as those know n in the art.

Formulations for rectal admini stration may be presented as a suppository with the usual carriers such as cocoa butter, synthetic glyceride esters or polyethylene glycol . Such carriers are typically solid at ordinary temperatures, but liquefy and/or dissolve in the rectal cav ity to release the drug.

Formulations for topical admi nistration in the mouth, for example buccally or sublingually, include lozenges compri sing the active ingredient in a flavoured basi s such as sucrose and acacia or tragacanth, and pastilles comprising the active ingredient in a basis such as gelatin and glycerine or sucrose and acacia. Exemplary compositions for topical administration include a topical carrier such as Plastibase (mineral oil gelled with polyethylene). Preferred unit dosage formulations are those containing an effective dose, as hereinbefore recited, or an appropriate fraction thereof, of the active ingredient.

It should be understood that in addition to the ingredients particularly mentioned above, the formulations of this invention may include other agents conventional in the art having regard to the type of formulation in question, for example those suitable for oral administration may include flavouring agents.

Whilst a compound of the invention may be used as the sole active ingredient in a

medicament, it is also possible for the compound to be used in combination with one or more further therapeutic agents. Accordingly there is provided a compound of formula (I) or (Γ) or a salt thereof, together with a further therapeutic ingredient, for simultaneous, sequential or separate administration. There is also provided a pharmaceutical composition comprising (i) a compound of formula (I) or (Γ) or a salt thereof; (ii) a pharmaceutically acceptable carrier; and (iii) a further therapeutic agent. There is also provided a kit of parts comprising: (a) a first pharmaceutical composition comprising a compound of formula (I) or (Γ) or a salt thereof, and a pharmaceutically acceptable carrier; and (b) a second pharmaceutical composition comprising a further therapeutic agent, for example a SIRT2 inhibitor, and a pharmaceutically acceptable carrier. Said further therapeutic agent may be a further S1RT2 inhibitor, for example a further compound according to the invention (i.e. a further compound of formula (I) or (Γ) or a salt thereof). Said further therapeutic agent may also be a different therapeutic agent; for example a further therapeutic agent useful for the treatment of a cancer, metabolic disorder, inflammatory disorder, neurodegenerative disorder or a central nervous system disorder. In one preferred embodiment, the further therapeutic agent is one which is useful in the prevention and/or treatment of a disease or disorder selected from breast cancer,

hepatocellular carcinoma, cervical cancer, liver cancer, brain cancer, kidney cancer, acute myeloid leukaemia, prostate cancer, pancreatic cancer, neuroblastoma, type II diabetes, prediabetes, insulin resistance syndrome, high blood pressure, abnormal cholesterol levels, polycystic ovary syndrome, metabolic syndrome, cardiovascular disease, vascular disease, hypercholesterolemia, obesity, dementia, Alzheimer' s disease, Parkinson' s disease and Huntington' s disease. In one preferred embodiment, the compound of the invention is administered in combination with an effective amount of an agent useful in the prevention or treatment of Parkinson^'s disease or the symptoms of Parkinson' s di sease, for example an agent selected from the group consisting of caffeine; nicotine; antioxidants, for example vitamins C and D; levodopa; a dopamine agoni st, for example bromocriptine, pergolide, pramipexole, ropini ole, piribedil, cabergoline, apomorphine, lisuride or apomorphine; a monoamine oxidase B inhibitor, for example selegiline or rasagiline; amantadine; an anticholinergic agent; quetiapine; a cholinesterase inhibitor; and modafmil. One or more of those further agents may be used in combination with a compound of the invention.

In another embodiment, the compound of the invention is administered in combination with an effective amount of an agent used in the prevention or treatment of Huntington' s di sease or the symptoms of Huntington' s disease, for example an agent selected from the group consisting of tetrabenazine; a neuroleptic; a benzodiazepine; amantadine; remacemide;

valporic acid; a dopamine agonist, for example bromocriptine, pergolide, pramipexole, ropinirole, piribedil, cabergoline, apomorphine, lisuride or apomorphine; a monoamine oxidase B inhibitor, for example selegiline or rasagiline; amantadine; an anticholinergic agent; quetiapine; a cholinesterase inhibitor, modafinil; a selective serotonin reuptake inhibitor; and mirtazapine. One or more of those further agents may be used in combination with a compound of the invention.

In another embodiment, the compound of the invention is administered in combination with an effective amount of an agent used in the prevention or treatment of Alzheimer^' s Di sease or the symptoms of Alzheimer' s disease, for example an agent selected from the group consisting of an acetylcholinesterase inhibitor, for example tacrine, rivastigmine, galantamine or donepezil; an MD A receptor antagonist, for example memantin or huperzine A; and antipsychotic agents. One or more of those further agents may be used in combination with a compound of the invention.

In a further embodiment; the compound of the invention may be effectively admini stered in combination with an effective amount of an anti-cancer agent, for example a

chemotherapeutic agent (also known as a cytotoxic agent). Examples of chemotherapeutic agents include alkylating agents (for example cisplatin, carboplatin, oxaliplatin, nitrogen mustards (e.g. mechlorethamine, cyclophosphamide, melphalan, chlorambucil, ifosfamide and busulfan), nitrosoureas ( e.g. N-Nitroso-N-methylurea, carmustine, lomustine and semustine, fotemustine and streptozotocin), tetrazines (e.g. dacarbazine, mitozolomide and temozolomide), aziri dines (e.g. thiotepa, mytomycin and diaziquone) and al kyl sulfonates (e.g. busulfan); anti-metabolites (for example anti-folates, fluoropyrimidines,

deoxynucleoside analogues and thiopurines); anti-mi crotubule agents (for example vinca alkaloids (e.g. vincristine, vinblastine, vinorelbine, vindesine, and vinflunine) and taxanes (e.g. paclitaxel and docetaxel)); topoisomerase inhibitors (for example irinotecan, topotecan, etoposide, doxorubicin, mitoxantrone, teniposide, novobiocin, merbarone, and aclarubicin); cytotoxic antibiotics (for example anthracyclines (e.g. doxorubicin, daunorubicin, epirubicin, idaaibicin, pirarubicin, aclarubicin, and mitoxantrone), actinomycin, bleomycin, plicamycin and mitomycin); antibody-drug conjugates (for example Gemtuzumab ozogamicin,

Brentuximab vedotin and Trastuzumab emtansine) or tyrosine-kinase inhibitors (for example imatinib, gefitinib, erlotinib and sunitinib). One or more of those further agents may be used in combination with a compound of the invention.

In a preferred embodiment the compound of the invention is administered in combination with an effective amount of a cheniotherapeutic agent selected from an alkylating agent (for example cisplatin, carboplatin, oxaliplatin, nitrogen mustards (e.g. mechlorethamine, cyclophosphamide, melphalan, chlorambucil , ifosfamide and busulfan ), nitrosoureas (e.g. N- Nitroso-N-methylurea, carmustine, lomustine and semustine, fotemustine and streptozotocin), tetrazines (e.g. dacarbazine, mitozolomide and temozolomide), aziridines (e.g. thiotepa, mytomycin and diaziquone) and alkyl sulfonates (e.g. busulfan), an anti-microtubule agent (for example vinca alkaloids (e.g. vincristine, vinblastine, vinorelbine, vindesine, and vinflunine) and taxanes (e.g. paclitaxel and docetaxel)), a cytotoxic antibiotic (for example anthracyclines (e.g. doxorubicin, daunorubicin, epirubicin, idarubicin, pirarubicin, aclarubicin, and mitoxantrone), actinomycin, bleomycin, plicamycin and mitomycin); and a tyrosine-kinase inhibitor (for example imatinib, gefitinib, erlotinib and sunitinib). More preferably the cheniotherapeutic agent is selected from ci splatin, carboplatin, oxaliplatin, nitrogen mustards (e.g. mechlorethamine, cyclophosphamide, melphalan, chlorambucil, ifosfamide and busulfan), paclitaxel, epirubicin, imatinib, gefitinib, erlotinib and sunitinib. The above further therapeutic agents, when employed in combination with the compounds of the present invention, may be used, for example, in those amounts indicated in the Physicians' Desk Reference (PDR) or as otherwise determined by one of ordinary skill in the art. Where an compound of the invention is utilized in combination with a further therapeutic agent(s), either concurrently or sequentially, the following combination ratios and dosage ranges are preferred: when combined with a further therapeutic agent, the compound of the invention may for example be employed in a weight ratio to the further therapeutic agent within the range from about 99: 1 to 1 :99, for example from about 10: 1 to about 1 : 10.

Where the compound of the invention is administered in combination with a further therapeutic agent, the individual components of such a combination may be administered separately at different times during the course of therapy or concurrently in divided or single combination forms. The present invention is therefore to be understood as embracing all such regimes of simultaneous or alternating treatment and the term "administering" is to be interpreted accordingly.

In one embodiment, the compound of the invention comprises an isotope atom, preferably a radioactive isotope atom. As defined herein, an isotope atom is an atom of an element that is not the most common naturally occurring isotope. The presence of isotope atoms (e.g.

deuterium) in compounds of the invention may affect the metabolic properties of the compounds. Such compounds may alternatively or additionally find use as diagnostic agents for the diagnosis of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect. Accordingly, the present invention also provides a compound of formula (I) or (Γ), said compound comprising an isotope atom (preferably a radioactive isotope atom), or a salt thereof, for use as a diagnostic agent for the diagnosis of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect.

The compounds of the invention also find use as reference compounds in methods of discovering other inhibitors of SIRT2. Thus, the invention also provides use of a compound of formula (I) or (Γ) (for example a compound comprising an isotope atom, preferably a radioactive isotope atom) or a salt thereof, as a reference compound in a method of identifying a further inhibitor of SIRT2. For example, such a method may involve a competitive binding experiment in which binding of a compound of formula (I) or (Γ) to SIRT2 is reduced by the presence of a further compound which has SIRT2 binding characteristics, for example stronger SIRT2-binding characteristics than the compound of formula (I) or (Γ).

Numerous synthetic routes to the compounds of the present invention can be devised by any person skilled in the art and the exemplified synthetic routes described below do not limit the invention. Where appropriate, any initially produced compound according to the invention can be converted into another compound according to the invention by known methods.

The invention also provides a process for the preparation a compound of formula (IB ), or a salt thereof,

wherein A is -(CH₂)m-; m is 1, 2, or 3; B is -(CH₂)_n-; n is 1, 2 or 3; R¹ is selected from the group consisting of unsubstituted -Ci-6alkyl;

5- 10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4alkyl, -CF_3> -CN, -OCi_-4alkyl and -OCF₃; and

6- 10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4alkyl, -CF_3> -CN, -OCi_-4alkyl and -OCF₃;

B is -(CH₂)_n-; n is 1, 2 or 3;

R² is selected from the group consisting of 5- 10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4alkyl, -CF₃, -CN -OCi_-4alkyl and -OCF₃; and

6- 10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH,

-Ci_-4alkyl, -CF₃, -CN -OCi_-4alkyl and -OCF₃;

R³ is selected from the group consisting of hydrogen;

Ci-6alkyl which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of -F, -OH, -OCH₃, -OCF₃ and -CN;

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi_-4alkyl, -CN, -CF₃ and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and 3-10-membered heterocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi_-4alkyl, -CN, -CF₃ and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and

R⁴ is hydrogen; the process comprising:

(i) reacting a compound of formula (IF) in which R³ is as defined for the compound of formula (IB ) above, with a compound of formula (IIF) in which LG represents a leaving group, and in which R² and B are as defined for the compound of formula (IB ) above, to produce a compound of formula (IV)

(II ) (IV)

(ii) converting the compound of formula (IV) to a compound of formula (V) by treatment with acid in the presence of water

(IV) (V) ; and

(iii) reacting the compound of formula (V) with a compound of formula (VI^'), in which R¹ and A are as defined for the compound of formula (IB ) above, and with a reducing agent to produce said compound of formula (IB ^')

(V) OB^') _{; and}

(iv) optionally converting the compound of formula (IB ) to a salt thereof.

In step (i), a compound of formula (IF) is reacted with a compound of formula (III ). The leaving group in the compound of formula (III ) may for example be a halogen such as chlorine, or it may be a tosylate (CH3C6H4S(0)20-), mesylate (CH3S(0)20-) or triflate (CF₃S(0)20-) group. Step (i) is typically carried out in the presence of a solvent, for example a polar aprotic solvent such as DMF. Step (i) is typically carrier out in the presence of a base, for example an inorganic base such as caesium carbonate. Step (i) may be carried out at ambient temperature.

In step (ii), a compound of formula (IV) is converted to a compound of formula (V) by treatment with acid in the presence of water. The acid used in step (ii) may for example be trifluoroacetic acid. An organic solvent such as dichloromethane may be used in step (ii). Step (ii) may be carried out at ambient temperature.

In step (iii), a compound of formula (V) is reacted with a compound of formula (VI ), and with a reducing agent. The reducing agent may for example be sodium

triacetoxyborohydride. Step (iii) is generally carried out in the presence of an organic solvent such as tetrahydrofuran. Step (iii) may be carried out at ambient temperature. In one preferred embodiment, a compound of formula (V), a compound of formula (VI ) and sodium triacetoxyborohydride are admixed in THF at ambient temperature.

In step (iv), conversion of a compound of formula (IB ) to a salt thereof may be carried out using routine methods. For example, where a compound of formula (IB ) is in the form of a free base, it may be converted to a hydrochloride salt by dissolving the compound of formula (IB ) in a suitable solvent, adding HC1 dissolved in a suitable solvent to form the

hydrochloride salt, and removing the solvent.

Compounds of formula (IF) in which R³ is hydrogen may for example be produced as shown below:

Scheme 1

(VF) (VIF) (IF)

Reagents and conditions: (a) Methyl 2-cyanoacetate, S₈, Et₂ H, EtOH, rt, 16 h.

(b) H2CHO, H4HCO2, 150 °C (MW), 30 min. The process described above is particularly useful for the synthesis of SIRT inhibitors of formula (IB ) in which A is -CH₂-; B is -CH₂-; and R³ is hydrogen.

Compounds of formula (ΙΓ) in which R³ is phenyl may for example be producible by an analogous process to that shown in Scheme 1 but using benzamide in step (b) in place of formamide.

Compounds of formula (IA) in which A is -(CH₂)m-; m is 1, 2, or 3; B is -(CH₂)_n-; n is 1, 2 or 3; R¹ is selected from the group consisting of unsubstituted Ci-6alkyl;

6- 10-membered which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4alkyl, -CF_3; -CN, -OCi_-4alkyl and -OCF₃; B is -(CH₂)_n-; n is 1, 2 or 3; R² is selected from the group consisting of

5- 10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4alkyl, -CF₃, -CN -OCi_-4alkyl and -OCF₃; and

6- 10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4alkyl, -CF₃, -CN -OCi_-4alkyl and -OCF₃;

R³ is hydrogen; R⁴ is hydrogen; R⁵ is hydrogen; and R⁶ is methyl may for example be produced according to the following scheme:

XIII IA in which the compound of formula (VIII) is converted to its methyl ester; the compound of formula (IX) then undergoes a Gewald reaction (e.g. by treatment with ethyl 2-cyanoacetate, S₈, and Et2 H) to produce the compound of formula (X); the compound of formula (X) is then treated with formamide and ammonium formate at elevated temperature to produce the compound of formula (XI); the compound of formula (XI) is reacted with a compound of formula (ΠΓ) as defined above, to produce the compound of formula (XII); the ester- containing compound of formula (XII) is then reacted with DIBAL at low temperature (e.g. - 78°C) either to produce aldehyde (XIII) directly or, where over-reduction occurs, to produce the corresponding alcohol which is then oxidised to produce aldehyde (XIII) (e.g. using an oxidant such as TPAP- NMO, or Swern conditions); the compound of formula (XIII) is then reacted with a compound of formula (VF) as defined above, and with a reducing agent, to produce a compound of formula (IA).

The processes of the invention may comprise additional processing steps to those shown; for example intermediates and/or final compounds may be subject to purification. Where protecting groups are used, the process may comprise routine protection and/or deprotection steps. Synthesis of Example Compounds

Chemistry Materials and Methods

Chemical shifts (δ) are quoted in parts per million (ppm) and are referenced to a residual solvent peak: CDC1₃ (δ_Η: 7.26, 5_C: 77.0), DMSO-d₆ (δ_Η: 2.50, 5_C: 39.5). Coupling constants (J) are quoted in Hertz (Hz). Enantiomers of the compound of example 1 were resolved by preparative HPLC, using a ChiralPak OJ-H 20 x 250 mm column and 35% 2-propanol containing 0.25% DEA in CO2 mobile phase (flow rate: 70 ml/min, detection: 220 nm). Purities of all assayed compounds were determined by combustion analysis or analytical HPLC and were found to have >95% purity unless otherwise specified. All manipulations of air or moisture sensitive materials were carried out in oven- or flame-dried glassware under an inert atmosphere of nitrogen or argon. Syringes, which were used to transfer reagents and solvents, were purged with nitrogen prior to use. Reaction solvents were distilled from CaH₂ (CH2CI2), Na/Ph₂CO (THE) or obtained anhydrous from commercial suppliers (DMF). All reagents were obtained from commercial suppliers and used without further purification unless indicated otherwise.

Intermediate 1

Methyl 2'-aminospiro[l,3-dioxolane-2,7'-4,5,6,7a-tetrahydro-3aH-benzothiophene]-3'- carboxylate

A solution of diethylamine (882 μΐ_^, 8.55 mmol) in EtOH (3 mL) was added dropwise to a solution of commertially available 1,4-cyclohexanedione monoethylene acetal (4.0 g, 25.64 mmol), methyl 2-cyanoacetate (1.5 mL, 17.09 mmol) and elemental sulfur (547 mg, 17.09 mmol) in EtOH (5 mL). The resultant mixture was stirred at room temperature for 16 h and then cooled to -20 °C for 2 h. The product was collected by filtration under reduced pressure and triturated with hexane to give the title compound (4.28 g, 93%) as a white solid: mp 74- 76 °C; ¾ NMR (400 MHz, CDCI3) δ 1.88 (t, J = 6.6 Hz, 2H), 2.72 (s, 2H), 2.90 (t, J = 6.6 Hz, 2H), 3.77 (s, 3H), 4.00 (s, 4H), 5.97 (br s, 2H); ¹³C NMR (100 MHz, CDCI3) δ 25.3, 31.4, 34.8, 50.6, 64.6 (2C), 105.0, 108.2, 114.2, 131.4, 162.6, 166.3; MS (ESI) m/z 270 (M+H)⁺; HRMS (ESI) m/z calcd for C12H16NO4S (M+H)⁺: 270.0800, found: 270.0802.

Intermediate 2

Spiro[l,3-dioxolane-2,8'-3,4b,5,6,7,8a-hexahydrobenzothiopheno[2,3-d]pyrimidine]-4'- one

A mixture of methyl 2'-aminospiro[l,3-dioxolane-2,7'-4,5,6,7a-tetrahydro-3aH- benzothiophene]-3'-carboxylate (Intermediate 1) (3.0 g, 11.15 mmol), formamide (20 mL, excess) and ammonium formate (5.62 g, 89.20 mmol) was heated to 150 °C in a microwave reactor for 30 min. The mixture was cooled to room temperature and H₂0 (30 mL) was added. The resultant solid was collected by filtration under reduced pressure and triturated with H₂0 to yield the title compound (1.24 g, 42%) as an off-white solid: mp 215-218 °C; ¾ MR (400 MHz, DMSO-d₆) δ 1.87 (t, J= 6.2 Hz, 2H), 2.92 (s, 2H), 3.00 (t, J = 6.2 Hz, 2H), 3.94 (s, 4H), 8.01 (s, 1H), 12.35 (br s, 1H); ¹³C NMR (100 MHz, DMSO-d₆) δ 24.3, 31.0, 35.3, 64.4 (2C), 107.5, 122.5, 130.1, 130.2, 145.6, 158.1, 163.5; MS (ESI) m/z 265 (M+H)⁺; HRMS (ESI) m/z calcd for Ci2Hi₃N₂0₃S (M+H)⁺: 265.0647, found: 265.0636; Anal, calcd for Ci₂Hi₂N₂0₃S: C, 54.53; H, 4.58; N, 10.60; found: C, 54.46; H, 4.48; N, 10.73.

Intermediate 3

3'-[(2-Methoxy-l-naphthyl)methyl]spiro[l,3-dioxolane-2,8'-5,6,7,8a-tetrahydro-4bH- benzothiopheno[2,3-d]pyrimidine]-4'-one

To a solution of spiro[l,3-dioxolane-2,8'-3,4b,5,6,7,8a-hexahydrobenzothiopheno[2,3- d]pyrimidine]-4'-one (Intermediate 2) (1.0 g, 3.79 mmol) in DMF (15 mL) were added 1- (chloromethyl)-2-methoxynaphthalene (1.17 g, 5.69 mmol) and CS2CO3 (6.18 g, 18.95 mmol). The resultant mixture was stirred at room temperature for 16 h. The suspension was partitioned between EtOAc (100 mL) and H2O (100 mL). The organic phase was separated and washed with brine (100 mL), dried over MgS04, filtered and the solvent evaporated under reduced pressure. The residue was purified by silica gel flash-column chromatography, with hexanes/EtOAc (7:3) as the eluent, to give the title compound (1.2 g, 73%) as a white solid: mp 162-164 °C; ¾ NMR (400 MHz, CDCI3) δ 2.01 (t, J = 6.4 Hz, 2H), 2.97 (s, 2H), 3.33 (t, J = 6.4 Hz, 2H), 4.01 (s, 3H), 4.04 (s, 4H), 5.66 (s, 2H), 7.32-7.38 (m, 2H), 7.48-7.52 (m, 1H), 7.80 (d, J = 8.1 Hz, 1H), 7.83 (s, 1H), 7.91 (d, J = 9.2 Hz, 1H), 8.03 (d, J = 8.8 Hz, 1H); ¹³C NMR (100 MHz, CDCI3) δ 24.3, 31.1, 35.6, 38.1, 56.3, 64.7 (2C), 107.9, 112.5, 115.6, 121.9, 122.9, 124.1, 127.9, 128.5, 129.1, 130.5, 130.6, 131.4, 132.9, 145.8, 156.0, 158.1, 162.6; MS (FTMS) m/z 435 (M+H)⁺; HRMS (FTMS) m/z calcd for C24H23N2O4S (M+H)⁺: 435.1379, found: 435.1374. Intermediate 4

3-[(2-Methoxy-l-naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH-benzothiopheno[2,3- d]pyrimidine-4,8-dione

To a solution of 3'-[(2-methoxy-l-naphthyl)methyl]spiro[l,3-dioxolane-2,8'-5, 6,7,8a- tetrahydro-4bH-benzothiopheno[2,3-d]pyrimidine]-4'-one (Intermediate 3) (1.0 g, 2.30 mmol) in CH2CI2 (20 mL) and H2O (2 mL) was added trifluoroacetic acid (5 mL). The resultant mixture was stirred at room temperature for 16 h. The solution was partitioned between CH2CI2 (50 mL) and sat. aq. NaHCC (50 mL). The organic phase was separated and washed with brine (50 mL), dried over MgSC^, filtered and the solvent evaporated under reduced pressure to give the title compound (854 mg, 95%) as a pale yellow solid: mp: 216- 219 °C; ¹H MR (400 MHz, CDCI3) δ 2.75 (t, J= 6.8 Hz, 2H), 3.57 (t, J = 6.8 Hz, 2H), 3.62 (s, 2H), 4.03 (s, 3H), 5.68 (s, 2H), 7.34-7.40 (m, 2H), 7.51-7.55 (m, 1H), 7.82 (d, J = 8.1 Hz, 1H), 7.90 (s, 1H), 7.94 (d, J = 9.2 Hz, 1H), 8.06 (d, J = 8.4 Hz, 1H); ¹³C MR (100 MHz, CDCI3) δ 24.4, 38.5, 38.6, 39.6, 56.4, 112.5, 115.3, 121.4, 122.8, 124.1, 127.9, 128.6, 129.1, 129.5, 131.2, 131.6, 132.9, 146.4, 156.1, 158.1, 163.2, 206.6; MS (FTMS) m/z 391 (M+H)⁺; HRMS (FTMS) m/z calcd for C22H19N2O3S (M+H)⁺: 391.1116, found: 391.1115.

Example 1

3-[(2-Methoxy-l-naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

To a solution of 3-[(2-methoxy-l-naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH- benzothiopheno[2,3-d]pyrimidine-4,8-dione (Intermediate 4) (70 mg, 0.18 mmol) in THF (5 mL) were added 3-picolylamine (18 μL, 0.18 mmol), sodium triacetoxyborohydride (114 mg, 0.54 mmol) and acetic acid (cat.). The resultant mixture was stirred at room temperature for 16 h. THF was evaporated under reduced pressure and the residue partitioned between EtOAc (10 mL) and sat. aq. Na₂C03 (10 mL). The organic layer was separated, washed with brine (10 mL), dried over MgS04, filtered and the solvent evaporated under reduced pressure. The residue was purified by silica gel flash-column chromatography, with CFTiCh/MeOH (9: 1) as the eluent, to yield the title compound (43 mg, 52%) as a white solid: mp 138-140 °C; ¾ NMR (400 MHz, CDC1₃) δ 1.74-1.83 (m, 1H), 2.11-2.16 (m, 1H), 2.61-2.66 (m, 1H), 3.02- 3.16 (m, 3H), 3.36 (dt, J = 18.3, 5.2 Hz, 1H), 3.92 (s, 2H), 4.02 (s, 3H), 5.66 (d, J = 2.1 Hz, 2H), 7.27 (d, J= 4.8 Hz, 1H), 7.33-7.38 (m, 2H), 7.49-7.53 (m, 1H), 7.71 (dt, J= 7.6, 2.2 Hz, 1H), 7.80 (d, J = 8.4 Hz, 1H), 7.84 (s, 1H), 7.92 (d, J= 9.2 Hz, 1H), 8.06 (d, J= 8.8 Hz, 1H), 8.51 (dd, J= 3.2, 1.6 Hz, 1H), 8.59 ( d, J= 2.0 Hz, 1H); ¹³C NMR (100 MHz, CDCI3) δ 24.0, 28.5, 32.1, 38.2, 48.5, 52.6, 56.3, 112.4, 115.5, 122.0, 122.9, 123.4, 124.0, 127.9, 128.5, 129.0, 131.1, 131.3, 131.4, 132.9, 135.6, 135.7, 145.6, 148.5, 149.6, 156.0, 158.1, 162.3; MS (ESI) m/z 483 (M+H)⁺; HRMS (FTMS) m/z calcd for C28H27N4O2S (M+H)⁺: 483.1855, found: 483.1846; Anal, calcd for C28H26N4O2S: C, 69.69; H, 5.43; N, 11.61; found: C, 69.60; H, 5.46; N, 11.58; HPLC: t_R= 12.00 min. Examples 2 and 3

(7R)-3-[(2-Methoxy-l-naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

(7S)-3-[(2-Methoxy-l-naphthyl)methyl]-7-(3-pyridylmethylamino)-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

3-[(2-methoxy-l-naphthyl)methyl]-7-(3-pyridylmethylamino)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one (Example 1) was separated into its enantiomers preparative chiral HPLC. The enantiomers had the following optical rotations: (+)-l [a]_D ²⁹ = +7 (c = 0.14, CHCls); (-)-l [a]_D ²⁹ = -7 (c = 0.14, CHCI3). xample 4

7-(Benzylamino)-3-[(2-methoxy-l-naphthyl)methyl]-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

Following the procedure described for the preparation of Example 1, 3-[(2-methoxy-l- naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH-benzothiopheno[2,3-d]pyrimidine-4,8-dione (Intermediate 4) (50 mg, 0.13 mmol) was treated with benzylamine (16 μΐ., 0.15 mmol), sodium triacetoxyborohydride (50 mg, 0.23 mmol) and acetic acid (cat.) in THF (5 mL) to give, after purification by silica gel flash-column chromatography with CFTiCh/MeOH (9: 1) as the eluent, the title compound (17 mg, 28%) as a dark grey solid: mp 168-170 °C; ¾ NMR (400 MHz, CDC1₃) δ 1.84-1.89 (m, 1H), 2.21-2.26 (m, 1H), 2.80-2.91 (m, 1H), 3.02- 3.14 (m, 3H), 3.35 (dt, J = 18.2, 5.2 Hz, 1H), 3.95 (s, 2H), 4.02 (s, 3H), 5.68 (d, J = 2.1 Hz, 2H), 6.80-6.95 (m, 1H), 7.20 (d, J = 7.6 Hz, 3H), 7.25-7.35 (m, 3H), 7.51-7.55 (m, 2H), 7.80 (d, J= 8.4 Hz, 1H), 7.84 (s, 1H), 7.92 (d, J = 9.2 Hz, 1H), 8.06 (d, J= 8.8 Hz, 1H); ¹³C NMR (100 MHz, CDCI3) δ 24.3, 28.7, 32.3, 38.2, 52.5, 55.5, 56.2, 112.5, 113.6, 115.8, 122.2, 122.8, 124.2, 127.7, 128.5, 129.1, 129.7, 131.3, 131.6, 131.7, 132.8, 141.9, 145.6, 156.1, 158.1, 159.9, 162.4; MS (ESI) m/z 482 (M+H)⁺; HRMS (EI) m/z calcd for C29H27N3O2S (M⁺): 481.1824, found: 481.1898; HPLC: t_R = 12.50 min. Example 5

3-[(2-Methoxy-l-naphthyl)methyl]-7-(o-tolylmethylamino)-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

Following the procedure described for the preparation of Example 1, 3-[(2-methoxy-l- naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH-benzothiopheno[2,3-d]pyrimidine-4,8-dione (Intermediate 4) (50 mg, 0.13 mmol) was treated with o-tolylmethanamine (16 μΐ., 0.14 mmol), sodium triacetoxyborohydride (50 mg, 0.23 mmol) and acetic acid (cat.) in THF (5 mL) to give, after purification by silica gel flash-column chromatography with CFTiCk/MeOH (9: 1) as the eluent, the title compound (11 mg, 28%) as a green solid: mp: 164-166 °C; ¾ NMR (400 MHz, CDC1₃) δ 1.84-1.89 (m, 1H), 2.21-2.26 (m, 1H), 2.4 (s, 3H), 2.80-288 (m, 1H), 3.02-3.14 (m, 3H), 3.35 (dt, J = 18.1, 5.2 Hz, 1H), 4.02 (s, 3H), 4.1 (s, 2H), 5.68 (d, J = 2.3 Hz, 2H), 6.84-6.94 (m, 1H), 7.18 (d, J = 7.6 Hz, 3H), 7.25-7.4 (m, 3H), 7.51-7.56 (m, 1H) 7.80 (d, J = 8.4 Hz, 1H), 7.84 (s, 1H), 7.92 (d, J = 9.2 Hz, 1H), 8.06 (d, J = 8.8 Hz, 1H); ¹³C NMR (100 MHz, CDCI3) δ 24.3, 28.7, 29.5, 30.8, 32.3, 38.2, 52.5, 55.2, 56.4, 112.5, 113.7, 115.7, 120.4, 122.1, 122.9, 124.1, 127.9, 128.6, 129.1, 129.5, 131.2, 131.5, 131.7, 132.9, 141.9, 145.6, 156.1, 158.1, 159.8, 162.3; MS (EI) m/z 495 (M⁺); HRMS (EI) m/z calcd for C30H29N3O2S (M⁺): 495.1980, found: 495.2013; HPLC: t_R = 12.54 min.

Example 6

3-[(2-Methoxy-l-naphthyl)methyl]-7-(2-thienylmethylamino)-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

Following the procedure described for the preparation of Example 1, 3-[(2-methoxy-l- naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH-benzothiopheno[2,3-d]pyrimidine-4,8-dione (Intermediate 4) (50 mg, 0.13 mmol) was treated with thiophen-2-ylmethanamine (16 μΐ., 0.14 mmol), sodium triacetoxyborohydride (50 mg, 0.23 mmol) and acetic acid (cat.) in THF (5 mL) to give, after purification by silica gel flash-column chromatography with CHiCh/MeOH (9: 1) as the eluent, the title compound (13 mg, 20%) as an off-white solid: mp 150-152 °C; ¾ NMR (400 MHz, CDCI3) δ 1.71-1.89 (m, 1H), 2.11-2.19 (m, 1H), 2.55-2.68 (m, 1H), 3.02-3.2 (m, 3H), 3.42 (dt, J = 18.3, 5.2 Hz, 1H), 4.02 (s, 3H), 4.23 (s, 2H), 5.68 (d, J = 2.1 Hz, 2H), 7.00 (s, J = 7.6 Hz, 2H), 7.2-7.3 (m, 1H), 7.32-7.45 (m, 2H), 7.49-7.53 (m, 1H), 7.80 (d, J = 8.4 Hz, 1H), 7.84 (s, 1H), 7.92 (d, J= 9.2 Hz, 1H), 8.06 (d, J = 8.8 Hz, 1H); ¹³C NMR (100 MHz, CDCh) δ 23.3, 28.6, 32.1, 38.2, 45.6, 52.1, 56.4, 66.7, 112.5, 115.6, 122.1, 122.9, 124.1, 124.5, 124.9, 126.7, 127.8, 129.1, 131.2, 131.4, 131.6, 132.9, 144.1, 145.7, 156.1, 158.2, 162.4; MS (ESI) m/z 488 (M+H)⁺; HRMS (FTMS) m/z calcd for C27H26N3O2S2 (M+H)⁺: 488.1466, found: 488.1432; HPLC: t_R = 12.26 min.

Example 7

7-[(3-Fluorophenyl)methylamino]-3-[(2-methoxy-l-naphthyl)methyl]-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

Following the procedure described for the preparation of Example 1 3-[(2-methoxy-l- naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH-benzothiopheno[2,3-d]pyrimidine-4,8-dione (Intermediate 4) (50 mg, 0.13 mmol) was treated with (3-fluorophenyl)methanamine (15 μΐ., 0.14 mmol), sodium triacetoxyborohydride (50 mg, 0.23 mmol) and acetic acid (cat.) in THF (5 mL) to give, after purification by silica gel flash-column chromatography with QHhCh/MeOH (9: 1) as the eluent, the title compound (13 mg, 20%) as a yellow solid: mp 156-159 °C; ¾ NMR (400 MHz, CDCh) δ 1.74-1.89 (m, 1H), 2.11-2.16 (m, 1H), 2.60-2.72 (m, 1H), 3.02-3.14 (m, 3H), 3.39 (dt, J = 18.1, 5.2 Hz, 1H), 3.91 (s, 2H), 4.02 (s, 3H), 5.68 (d, J= 2.0 Hz, 2H), 6.87-6.94 (m, 1H), 7.18 (d, J= 7.6 Hz, 2H), 7.25-7.35 (m, 2H), 7.35-7.45 (m, 2H) 7.51-7.56 (m, 1H) 7.80 (d, J = 8.4 Hz, 1H), 7.84 (s, 1H), 7.92 (d, J = 9.2 Hz, 1H), 8.06 (d, J = 8.8 Hz, 1H); ¹³C NMR (100 MHz, CDCh) δ 24.1, 28.5, 32.1, 38.2, 50.5, 52.5, 56.3, 112.1, 112.5, 112.9, 113.8, 114.0, 114.8, 115.0, 115.6, 123.6, 124.0, 127.9, 128.5, 129.1, 129.8, 129.9, 131.1, 131.4, 132.9, 145.6, 156.1, 158.1, 162.3; MS (ESI) m/z 500 (M+H)⁺; HRMS (EI) m/z calcd for C29H26FN3O2S (M⁺): 499.1730, found: 499.1735; HPLC: t_R = 12.33 min. xample 8

3-[(2-Methoxy-l-naphthyl)methyl]-7-[(3-methoxyphenyl)methylamino]-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

Following the procedure described for the preparation of Example 1, 3-[(2-methoxy-l- naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH-benzothiopheno[2,3-d]pyrimidine-4,8-dione (Intermediate 4) (50 mg, 0.13 mmol) was treated with (3-methoxyphenyl)methanamine (19 μΐ., 0.14 mmol), sodium triacetoxyborohydride (50 mg, 0.23 mmol) and acetic acid (cat.) in THF (5 mL) to give, after purification by silica gel flash-column chromatography with CFTiCk/MeOH (9: 1) as the eluent, the title compound (10 mg, 15%) as a pale green solid: mp 167-169 °C; ¾ NMR (400 MHz, CDC1₃) δ 1.74-1.88 (m, 1H), 2.11-2.19 (m, 1H), 2.61-2.66 (m, 1H), 3.02-3.21 (m, 3H), 3.36 (dt, J = 18.0, 5.1 Hz, 1H), 3.8 (s, 3H), 3.9 (s, 2H), 4.05 (s, 3H), 5.66 (d, J = 2.1 Hz, 2H), 6.82 (d, J = 7.6 Hz, 2H), 6.91 (t, J = 7.3 Hz, 1H) 7.25 (d, J = 7.6 Hz, 1H), 7.49-7.53 (m, 2H), 7.55 (dt, J = 7.6, 2.1 Hz, 1H), 7.80 (d, J = 8.4 Hz, 1H), 7.84 (s, 1H), 7.92 (d, J = 9.2 Hz, 1H), 8.06 (d, J = 8.8 Hz, 1H); ¹³C NMR (100 MHz, CDCI3) δ 24.2, 28.7, 30.7, 32.1, 38.2, 52.5, 55.2, 56.4, 59.2, 1 12.5, 1 13.7, 1 15.7, 120.4, 122.2, 122.9, 124.1, 127.9, 128.6, 129.1, 129.5, 131.2, 131.5, 131.7, 132.9, 141.9, 145.6, 156.1, 158.1, 159.8, 162.3; MS (ESI) m/z 512 (M+H)⁺; HRMS (FTMS) m/z calcd for C30H30N3O3S (M+H)⁺: 512.2008, found: 512.2010; HPLC: t_R = 12.44 min. xample 9

7-(2,2-Dimethylpropylamino)-3-[(2-methoxy-l-naphthyl)methyl]-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

Following the procedure described for the preparation of Example 1, 3-[(2-methoxy-l- naphthyl)methyl]-5,6,7,8a-tetrahydro-4bH-benzothiopheno[2,3-d]pyrimidine-4,8-dione (Intermediate 4) (50 mg, 0.13 mmol) was treated with neopentylamine (15 μΐ., 0.13 mmol), sodium triacetoxyborohydride (50 mg, 0.23 mmol) and acetic acid (cat.) in THF (5 mL) to give, after purification by silica gel flash-column chromatography with CFTiCh/MeOH (9: 1) as the eluent, the title compound (10 mg, 15%) as a dark grey solid: mp 147-149 °C; ¾ NMR (400 MHz, CDC1₃) δ 1.05 (s, 9H) 1.74-1.83 (m, 1H), 2.11-2.16 (m, 1H), 2.52 (s, 2H), 2.62-2.75 (m, 1H), 3.02-3.14 (m, 3H), 3.36 (dt, J = 18.3, 5.2 Hz, 1H), 4.02 (s, 3H), 5.68 (d, J = 2.1 Hz, 2H), 7.23 (d, J = 7.6 Hz, 1H), 7.49-7.53 (m, 1H), 7.71 (dt, J = 7.6, 2.1 Hz, 1H), 7.80 (d, J = 8.4 Hz, 1H), 7.84 (s, 1H), 7.92 (d, J = 9.2 Hz, 1H), 8.06 (d, J = 8.8 Hz, 1H); ¹³C NMR (100 MHz, CDCI3) δ 24.5, 27.7, 28.7, 31.4, 32.1, 38.3, 54.5, 56.4, 59.3, 112.5, 1 15.6, 122.1, 123.0, 124.1, 127.9, 128.6, 129.1, 131.1, 131.5, 131.8, 132.9, 145.6, 156.1, 158.1, 162.4; MS (ESI) m/z 462 (M+H)⁺; HRMS (FTMS) m/z calcd for C27H32N3O2S (M+H)⁺: 462.2215, found: 462.2223; HPLC: t_R = 12.18 min. Example 10:

7-[(4-fluorophenyl)methylamino]-3-(3-quinolylmethyl)-5,6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one

Example 10 may be prepared by a method analogous to that used to prepare the compound of Example 1, starting from Intermediate 2, and using 3-(chloromethyl)-quinoline in place of 1- (chloromethyl)-2-methoxynaphthalene, and using 4-fluorobenzylamine in place of 3- picolylamine.

Further Examples 11- 44 were also prepared by a method analogous to that used to the compound of Example 1, and their structures are shown in Table 1 below.

Table 1

CC1=C(CCNCC2=CC=C(0C)C=C2)SC3=C 1 C(N(CC4=C(OC)C=CC5=C4C=CC=C5)C =N3)=0

0=C 1N(C=NC2=C 1C(CCC(C3)NCC4=CN

=CN=C4)=C3S2)CC5=CC6=C(C=C5)C=CC

=C6

0=C1C2=C(SC3=C2CCC(C3)NCC4=CC=C

(C=C4)C#N)N=CN1CC5=CC=CC6=C5C=

NC=C6

0=C1C2=C(SC3=C2CCC(C3)NCCN4CC0 CC4)N=CN1CC5=CC=CC(C6=CC=CC=C6 )=C5

0=C1C2=C(SC3=C2CCC(C3)NCC4=CC=N N=C4)N=CN1CC5=CC=CC6=C5N=CC=C6

0=C1C2=C(SC3=C2CCC(C3)NC4CC(C=C C=C5)=C5C4)N=CN1CC6=CC=CC7=C6N =CC=C7

0=C1C2=C(SC3=C2CCC(C3)NC4=CC5=C

(NN=C5)C=C4)N=CN1CC6=CC=CC7=C6

C=NC=C7

0=C1C2=C(SC3=C2CCC(C3)NC4=CC5=C (0C05)C=C4)N=CN1CC6=CC=CC7=C6N =CC=C7

Examples 11-31 and 34-44 were prepared following a method analogous to that described for Example 1 above. Exam les 32 and 33 were prepared according to the following scheme:

Step 1 2 Step 2 ³

Synthesis of 2-(4-oxopentyl) isoindoline-l,3-dione (2):

To a stirred solution of 1 (20 g, 166 mmol) in DMF (150 mL), K2CO3 (46 g, 333 mmol) and 5-chloropentan-2-one (26.9 g, 183 mmol) was added. The reaction mixture was heated at 80°C for 16 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with ice water and filtered. The residue was washed with water, filtered and concentrated under reduced pressure. The crude material was used for next reaction without purification to afford title compound 2 (20g, crude).

Synthesis of ethyl 2-amino-5-(2-(l,3-dioxoisoindolin-2-yl)ethyl)-4-methylthiophene-3- carboxylate (3):

To a stirred solution of compound 2 (15g, 64.9 mmol) and ethyl 2-cyanoacetate (8.0g, 71.4mmol) in EtOH (200 mL), morpholine (19.5 mL) and sulfur (2.3 g, 72 mmol) were added and stirred at 50°C for 16 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with water and extracted with EtOAc. The combined organic layer was washed with brine, dried over anhydrous Na₂S04 and concentrated under reduced pressure. The crude product was purified by column chromatography using 40% EtOAc/hexane to afford title compound 3 (10.2g, 44%).

LCMS: 358.99(M+H). Synthesis of 2-(2-(5-methyl-4-oxo-3,4-dihydrothieno [2,3-d]pyrimidin-6- yl)ethyl)isoindoline-l,3-dione (4):

To a stirred solution of compound 3 (10.2g, 28.4 mmol) in formamide (120 mL), ammonium formate (3.58g, 56.9 mmol) was added and stirred at 120°C for 16 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with ice water and precipitated solid was filtered. The crude product was purified by column chromatography using 5% MeOH/Dichloromethane to afford title compound 4 (6.0g, 62.5%).

LCMS: 340.0(M+H); ¾ MR (400 MHz, DMSO-d) δ 12.3 (brs, 1H), 7.99(d, J = 8.4 Hz, 1H), 7.85(d, J = 7.8 Hz, 4H), 3.80 (t, 2H), 3.14 - 3.11 (m, 2H), 2.34 (s, 3H).

Synthesis of l-(bromomethyl)-2-methoxynaphthalene (5):

To a stirred solution of 2-methoxy-l-naphthaldehyde (15g, 80.6 mmol) in EtOH (200 mL), NaB¾ (6.2g, 161 mmol) was added and stirred at room temperature for 3 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was concentrated under reduced pressure. The residue was dissolved in water and extracted with dichloromethane. The combined organic layer was washed with brine, dried over anhydrous Na₂S04 and concentrated under reduced pressure. The crude product was dissolved in dichloromethane (200 mL), PBr₃ (32.7g, 120 mmol) was added dropwise and stirred at room temperature for 1 h. After completion of the reaction, the reaction mixture was quenched with water and extracted with dichloromethane. The combined organic layer was washed with brine, dried over anhydrous Na₂S04 and concentrated under reduced pressure to afford title compound 5 (10.2g, crude).

Synthesis of 2-(2-(3-((2-methoxynaphthalen-l-yl)methyl)-5-methyl-4-oxo-3,4- dihydrothieno [2,3-d]pyrimidin-6-yl)ethyl)isoindoline-l,3-dione (6):

To a stirred solution of 4 (6 g, 17.6 mmol) in DMF (60 mL), Cs₂C0₃ (11.6 g, 35.3 mmol) and 5 (6.6 g, 26.5 mmol) was added. The reaction mixture was room temperature for 16 h. The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with ice water and filtered. Residue was washed with water and filtered, concentrated under reduced pressure. The crude material was used for next reaction without purification to afford title compound 6 (5.0g, crude).

LCMS: 510.07(M+H). Synthesis of 6-(2-aminoethyl)-3-((2-methoxynaphthalen-l-yl) methyl)-5-methylthieno [2, 3-d] pyrimidin-4(3H)-one (ScCBl):

To a stirred solution of 6 (5.0 g, 9.82 mmol) in EtOH (50 mL), hydrazine hydrate (15 mL) was added and heated at 90°C for 16h. The progress of the reaction was monitored by TLC. After completion the reaction was evaporated to dryness. The crude product was purified by column chromatography using 7% MeOH/Dichloromethane to afford ScCBl (2.5 g, 67.5%). LC-MS: 380.05 (M+H); ¾ MR (400 MHz, DMSO-d) δ 8.19 (d, J = 8.6 Hz, 1H), 8.09 - 7.99 (m, 2H), 7.95 - 7.87 (m, 1H), 7.60 - 7.50 (m, 2H), 7.43 - 7.34 (m, 1H), 5.55 (s, 2H), 3.98 (s, 3H), 2.86 - 2.70 (m, 4H), 2.43 (s, 3H), 2.12 (s, 2H); HPLC: 99.8%.

Synthesis of 3-((2-methoxynaphthalen-l-yl) methyl)-5-methyl-6-(2-((pyridin-4-ylmethyl) amino) ethyl) thieno [2, 3-d] pyrimidin-4(3H)-one (ScCA4Bl):

To a stirred solution of compound 6 (200 mg, 0.52 mmol) in DCE (5mL), AcOH (0.19g, 3.16 mmol) was added followed by addition of respective amine (56.2mg, 0.52 mmol). The reaction mixture was stirred at room temperature for 2h. Sodium triacetoxyborohydride (163mg, 0.79mmol) was added and stirred at room temperature for 16h.The progress of the reaction was monitored by TLC. After completion of the reaction, the reaction mixture was quenched with water and extracted with EtOAc. The combined organic layer was washed with brine, dried over anhydrous Na₂S04 and concentrated under reduced pressure. The crude product was purified by column chromatography to afford title compound ScCA4Bl.

LC-MS: 471 (M+H).

Biological Assays and Studies - Details and Results (a) SIRT Enzymatic Assays

(i) Fluorogenic Assays

In vitro SIRT assays were conducted by using the fluorogenic peptide substrate from p53 residues 379-382 RHKK(Ac)-AMC for SIRT 1-3 and a Ac-Lys-succ-AMC for SIRT5. The assay buffer contains 50 mM Tris-HCl, pH 8.0, 137 mM NaCl, 2.7 mM KC1, 1 mM MgC12, 1 mg/mL BSA and 1% DMSO. The protocol involves a two-step procedure. The fluorogenic substrate with the acetylated lysine side chain is incubated with the SIRT enzyme to produce the deacetylated products, which are then digested in the second step by the addition of a developer to produce the fluorescent signal proportional to the amount of deacetylated substrates. Deacetylation of substrate peptides was used as a read out of the SIRT activity. All compounds were freshly prepared as 10 mM stock solutions in DMSO and serially diluted to the indicated concentration in the reaction, see Figure 2. All testing compounds were preincubated with the human SIRTs for about 10 min before commencing the reaction through the addition of the substrate. Fluorescence was read (excitatory: 360, emission: 460) using the EnVision Multilabel Plate Reader (Perkin Elmer). The percentages of enzyme activity (relative to DMSO controls) and IC50 values were calculated using the GraphPad Prism 4 program based on a sigmoidal dose-response equation. For this assay, suramin (Trapp, J., et al, ChemMedChem 2007, 2 1419-1431.) was used as a positive control (IC50 = 15.49 ± 0.37) and DMSO used as the negative control.

Results

Examples 1 to 10 were tested for SIRT2 activity in the SIRT2 enzymatic assay described above. The results are shown in Table 2:

Table 2

a Errors represent the standard deviation, calculated from two independent measurements. None of the example compounds used in this study gave any signal interference in this assay format.

The compound of Example 1 was assayed against SIRT1, 3 and 5 using the standard fluorogenic substrates. No inhibition against these isoforms was detected at concentrations up to 100 μΜ, revealing the compound of example 1 to be highly selective (>65-fold) toward SIRT2, as shown in the concentration/inhibition curve in Figure 2 (a). The compound of example 7 was also notably selective for SIRT2, as shown in the concentration/inhibition curve in Figure 2 (b), being 5.6-fold, 6.3-fold and 4.1-fold less potent against SIRT1, SIRT3 and SIRT5 respectively. Errors bars in Figure 2 represent the standard deviation, calculated from three independent measurements.

The compounds of Examples 11-44 were also tested for SIRT2 activity by the SIRT2 enzymatic assay described for Examples 1-10 above.

The compounds of Examples 11-44 were analysed by liquid chromatography-mass spectroscopy (LCMS) using an X-Select CSH C18 (4.6x50)mm 2.5u column, and a mobile phase of A) formic acid in water and B) 0.05% formic acid in acetonitrile. The LCMS used an injection volume of 3.0 uL, a flow rate of 1.0 mL/minute, and the following gradient program: 2% B to 98% B in 2.8 minutes, hold until 4.8 minutes, concentration of B is 2% at 5.0 minutes, up to 7.0 minutes. The retention times and [M+HJ+ ion masses obtained by LCMS, as well as the IC50 values obtained by the SIRT2 enzymatic assay, are given in Table 3 below. Table 3

22 487 1.27 2.27

23 471 1.72 2.21

24 478 0.39 2.15

25 456 1.52 2.4

26 472 1.74 2.25

27 483 1.83 2.25

28 497 2.75 2.91

29 514 5.11 2.99

30 484 5.03 3.43

31 453 4.25 3.61

32 471 2.93 3.18

33 500 3.36 2.64

34 454 5.30 2.25

35 478 4.72 1.75

36 501 3.14 3.16

37 455 71.9% inhibition at lOuM 1.91

38 479 60.9% inhibition at lOuM 3.75

39 479 62.3% inhibition at lOuM 1.90

40 483 75.6% inhibition at lOuM 3.20

41 478 56.0% inhibition at lOuM 2.28

42 477 58.3% inhibition at lOuM 2.12

43 450 70.5% inhibition at lOuM 2.18

44 402 38.3% inhibition at lOuM 2.22

(ii) SIRT-Glo™ Assays

SIRT-Glo™ Assays were performed by following the standard protocol from the manufacturer (Promega cat# G6450). The compound of Example 1 was incubated with SIRT1 or SIRT2 enzyme in the assay buffer for 10 min, and then the assay reagents were added to the reaction. The luminescent signal was read in En Vision Multilabel Plate Reader (Perkin Elmer) after 20-minute incubation. Data were plotted and IC50 values were determined using GraphPad Prism. Data represent the mean ± standard deviation of three independent measurements. Results

Assessment in an enzyme-coupled SIRT-Glo™ assay of the compound of Example 1 gave a comparable, albeit more potent result to the results for the fluorogenic assay, with a measured SIRT2 ICso of 0.17 ± 0.04 μΜ (n=3).

The effect of the compound of Example 1 on SIRT1 activity was assessed in the enzyme- coupled SIRT-Glo™ assay, which also revealed the compound to be highly (~50-fold) selective for SIRT2, as shown in Figure 3. (b) Redox activity and storage study

The compounds of examples 1, 6 and 7 were assessed for their ability to produce H2O2 in the presence of 1 mM DTT via redox cycling. In this assay, the known SIRT1 inhibitor EX-527 was used as a negative control, whereas NSC 663284 was used as a positive control (Johnston, P. A., et al, Assay Drug Dev. Technol. 2008, 6, 505-518.). The experiment was carried out in accordance to Lazo et al., 2008 to measure HRP catalysis of the oxidation of phenol red by H2O2. The assay was performed in a 384-well flat-bottomed clear polystyrene plate (Greiner Bio-One, Monroe, NC). Compounds (ΙΟΟμΜ) and or positive control (100 μΜ H2O2) were in HBSS containing 1 mM DTT in a volume of 20 μΐ.. Compounds and DTT were incubated together at room temperature for 15 min with a subsequent addition for 5 min of 100 μg/mL phenol red and 60 μg/mL HRP detection reagent. The assay was terminated by addition of 10 μΐ. of 1 M NaOH, and the absorbance of the phenol red was measured at 610 nm in a NovaSTAR plate reader (BMG).

A DMSO solution of the compound of example 1 was stored under ambient conditions with no special precautions for ~5 weeks. The purity of the stored sample (by ¾ NMR and HPLC-MS analysis) was measured after 5 weeks.

Results

The compounds of examples 1, 6 and 7 have little or no measurable redox activity at 100 μΜ, as shown in Figure 9. No issue with the stability of the compound of example 1 was observed upon prolonged storage. The purity of the stored sample of the compound of example 1 in DMSO after 5 weeks (by ¾ NMR and HPLC-MS analysis) was identical to the freshly prepared material. (c) SIRT2 Mechanism of Action Assays

Recombinant human SIRT2 (43-356) was expressed as a His-Sumo fusion protein in E. coli and purified by affinity chromatography (HisTrap, GE Healthcare; 50 mM Tris pH 8.0, 500 mM NaCl, 5% glycerol). The His-Sumo tag was cleaved over night at 4 °C using Sumo- protease (protein ratio 1/100) and removed through reverse affinity chromatography. The protein was further purified through gel filtration (S200 16/60, GE Healthcare; 25 mM BisTris propane pH 6.5, 150 mM NaCl, 1 mM TCEP). The deacetylase assay was performed as described by Smith et al {Anal. Biochem. 2009, 294, 101-109). Briefly, the reaction mix contained 0.8 μΜ SIRT2, constant 500 μΜ NAD⁺ for peptide titrations (50 to 600 μΜ) and constant 250 μΜ α-tubulin peptide, MPSD(ac)KTIG, (GL Biochem, Shangai, China) for NAD⁺ titrations (50 to 600 μΜ). NAD⁺ and peptide titrations were performed at 0, 1.25, 2.5, and 5 μΜ of the compound of example 1 with constant 5% DMSO in 20 mM sodium phosphate buffer pH 7.5. The reaction was started by adding SIRT2 and followed for 1 h at room temperature through the absorbance decay at 340 nm in a microplate spectrophotometer MQX200 (MWG-Biotech, Germany). The background signal was measured under similar conditions omitting the substrate peptide from the reaction. Results shown are the average of at least 2 measurements and kinetic parameters were determined using Grafit 7 (Erathicus Software, Horley, UK). Analogous assays varying NAD⁺ concentrations at different inhibitor levels were also run. Results

SIRT2 activity against tubulin-K40 peptide study revealed an activity pattern typical for competition, as shown in Figure 4 (a) (empty circles 0 μΜ; filled triangles 1.25 μΜ; empty triangles 2.5 μΜ; filled squares 5 μΜ), with an increase of the K_m for the peptide in presence of the compound of example 1. As the pattern was present, it was used as the model for fitting the data (lines) in Figure 4 (a).

The Ki for this peptide competitive SIRT2 inhibition by the compound of Example 2 (the (-)- enantiomer of the compound of Example 1) was determined to be 0.62 ± 0.15μΜ (n=2).

The analogous assays varying NAD⁺ concentrations at different inhibitor levels resulted in an activity pattern consistent with non-competitive inhibition, possibly with a small mixed component, as shown in Figure 4 (b) (empty circles 0 μΜ; filled triangles 1.25 μΜ; empty triangles 2.5 μΜ; filled squares 5 μΜ). The activity pattern (lines) was best fitted by the noncompetitive inhibition model (upper graph, Figure 4 (b)). Competitive and un-competitive models did not adequately fit the data. Using a mixed-type model improved the fit slightly (lower graph, Figure 4 (b)), which might indicate a small mixed-type component in the inhibition.

These results indicate that the compound of example 1 likely blocks the acetyl-lysine binding site of SIRT2, but shows no or only small overlap with the NAD⁺-binding pocket.

(d) Docking Studies

(i) SIRT2 docking study

Both enantiomers of the compound of example 1 (i.e. the compounds of examples 2 and 3) were docked into the active site of human SIRT2. Two protein structures were employed for this analysis: a human SIRT2 X-ray crystal structure (PDB ID: 1J8F) (Nguyen, G. T., et al,. Chem. Biol. 2013, 20, 1375-1385.). That crystal structure is an apo-protein. Additionally docking studies were performed on a ligand-bound structure: a human SIRT2 homology model was generated, predicted by the SWISS-MODEL server (Arnold, K., et al,

Bioinformatics 2006, 22, 195-201.), using the yeast Hst2 (yHst2) Sir2 X-ray crystal structure (PDB ID: 1Q17) (Zhao, K., et al, Structure 2003, 77, 1403-1411) as a template. The yeast Hst2 structure is in ternary complex with 2'-0-acetyl ADP ribose and an acetylated histone H4 peptide.

To further validate the docking and biochemical findings, the compounds of examples 4 and 8 were also docked at the active site of human SIRT2 X-ray crystal structure.

Results

Docking studies of the compound of example 1 with the human SIRT2 X-ray crystal structure consistently gave higher-scoring binding modes, through the presence of stronger

intermolecular interactions. The top-scoring poses of both optical isomers of the compound of example 1 (i.e. examples 2 and 3) were predicted to bind to the acetylated-substrate pocket rather than the cof actor-binding cavity, in accordance with the mechanism of action studies {vide supra), displaying strong intermolecular interactions with the neighbouring active site amino acid residues and no clashes with the binding cleft. Furthermore, the 3 top-scoring poses (RMSD <1) for each enantiomer gave comparable docking scores, which supports the biochemical data obtained.

Figure 5 (a) shows the predicted binding pose of the compound of example 1 (space-filling representation) at the active site of human SIRT2 (molecular surface representation, PDB ID: 1J8F). NAD⁺-binding site (orange surface), Ac-Lys pocket (green surface) and Hisl87 (blue surface) are displayed. Figures 5 (b) and (c) show close-up views of the compound of example 1 (yellow stick representation) docked into the acetylated-substrate binding domain of SIRT2 (cyan ribbon and molecular surface representation). Active site residues (blue stick representation) and a key water molecule (red ball) are displayed.

Visual inspection of the top-ranked pose of the compound of example 1, at the active site of human SIRT2 X-ray structure, revealed a number of favourable intermolecular interactions, as shown in Figure 5. The heterotri cyclic core scaffold is well accommodated into the acetylated-substrate binding tunnel, which allows the suitable positioning of the two opposite aromatic moieties, the pyridine and the naphthyl rings, in highly hydrophobic clefts. The pyridine ring, sandwiched between Hisl87 and Phel 19, forms π-stacking interactions with these residues, whereas the free amino N-H group is hydrogen bonded to a tightly bound water molecule. On the other hand, the naphthyl moiety establishes several aromatic and hydrophobic interactions with Tyrl65, Phe243, Met247, Pro268, Phe269 and Leu272 amino acid residues. All these favourable interactions may explain the high potency showed by the compound of example 1. The compounds of examples 4 and 8 displayed similar binding modes to the compound of example 1; the top-ranked docking solutions of both analogues showed lower scores which correlates with the in vitro enzymatic data.

(ii) Isoform docking study

To rationalise the high SIRT2 isoform selectivity of the compound of example 1, as revealed by the biochemical assays, it was decided to model a superposition of the SIRT2 protein, bound to the compound of example 1, with the crystal structures of SIRT1 (PDB ID: 4IG9), SIRT3 (PDB ID: 3GLS) and SIRT5 (PDB ID: 2B4Y).

Results

It was found that the compound of example 1 can no longer maintain the same binding mode within the catalytic site of other SIRT isozymes. Figure 5 (d) shows rigid superposition of SIRT1 (pink ribbon representation, PDB ID: 4IG9), SIRT2 (cyan ribbon and molecular surface representation, PDB ID: 1J8F), SIRT3 (green ribbon representation, PDB ID: 3GLS) and SIRT5 (orange ribbon representation, PDB ID: 2B4Y) crystal structures. The compound of example 1 (yellow stick representation) is displayed docked into the acetylated-substrate binding domain of SIRT2, and critical active site residues (stick representation) are displayed.

As can be seen from Figure 5 (d), several clashes were observed between the compound of example 1 and major loops in the active site of SIRT1, 3 and 5. In particular, the Leu239 and Pro268 residues of SIRT1, SIRT3 and SIRT5 were found to clash with the docked ligand. While Leu239 and Pro268 are conserved in SIRT2, these residues are further away from the docked ligand, due to increased space in the SIRT2 binding pocket.

( ) MCF-7 Cellular Assays

To gauge the cellular activity of the compound of Example 1, the acetylation status of a- tubulin, an established SIRT2 biomarker, was examined by western blot analysis in MCF-7 breast cancer cell lines.

Michigan Cancer Foundation-7 cell line (MCF-7) was pure and grown as a monolayer in DMEM (Dulbecco's Modified Eagle Medium) supplemented with 10% FBS (Fetal Bovine Serum), 100 μg/mL streptomycin and 100 units/mL penicillin. Cells were incubated at 37 °C in an atmosphere of 5% of C0₂.

MCF-7 cells were treated with various doses of the compound of example 1, and with a comparator compound used as a control (a known 10, 1 l-dihydro-5H-dibenz[£,/]azepine derivative, Di Fruscia, P., et al, MedChemComm 2012, 3, 373-378), for 24 hours.

Comparator compound

Cells were then harvested and western blot analysis was performed to determine the levels of FOX03a, acetylated-a-tubulin and ^-tubulin. The cellular experiment was repeated four times.

For the Western blot analysis, whole-cell lysates were obtained and western blot analysis performed as previously described (Essafi et al, Methods Mol. Biol, 2009, 462, 201-211). 20- 25 μg of whole-cell protein extracts were resolved on 8-15% SDS-PAGE gels, transferred onto Protran nitrocellulose membranes (Perkin Elmer) and incubated with specific antibodies in 1 : 1000 dilution. Antibodies against FOX03a (#2497) were purchased from Cell Signaling Technology (Hitchin, UK). Antibodies against acetylated tubulin [6-1 IB- 1] antibody (ab24610) were from Abeam (Cambridge, UK) and ^-tubulin (sc-53646) from (Santa Cruz Biotechnology, Autogen Bioclear, Wiltshire, UK).

Representative western blot data are shown in Figure 6 (upper panel). Quantification of protein expression was performed using ImageJ software (Image Processing and Analysis in Java). Quantified acetylated-a-tubulin levels were normalised to ^-tubulin (see Figure 6 lower panel).

Clonogenic assays were performed to assess the colony formation efficiency of MCF-7 cells following treatment with the compound of example 1 or the comparator compound shown above. A total of 2000 cells were seeded in six well plates, and treated with 0, 0.25, 5, 12.5 and 25 μΜ of the compound of example 1 or the comparator compound, and cultured up to 15 days until cells formed colonies. Colonies were washed three times with PSB and fixed with 4% PFA for 20 min at room temperature. Visible colonies consisting of at least 50 cells were stained with 0.5% crystal violet (Sigma) and left to air dry at room temperature for a few days. Acetic acid 33% (v/v) was then added to solubilise the bound crystal violet and the optical density (OD) was then measured at 592 nm using a microplate reader (Sunrise, Tecan).

Results

The results of the cellular assay in MCF-7 Cells are shown in Figure 6. The compound of Example 1 was more effective in inducing FOX03a accumulation and tubulin acetylation compared with the comparator compound.

Increases in the acetyl-a-tubulin level were observed upon treatment with the compound of example 1. Relative to an untreated control, acetyl a-tubulin levels increase in a dose dependent manner from 0.5 μΜ, with the effect being largest at 1 μΜ. Beyond a dose of 2.5 μΜ the acetyl tubulin level plateaus. Higher concentrations were required to observe a comparable, albeit less dose dependent response with the comparator compound, as shown in Figure 6. The concentrations required to mediate these effects are in line with the different SIRT2 potencies of these two inhibitors: Example 1 SIRT2 IC50 = ~1 μΜ (depending on assay); Comparator Compound SIRT2 IC50 = 18 μΜ.

The western blot results revealed that both the compound of Example 1 and the comparator compound induced the accumulation of FOX03a, but with the compound of example 1 being more effective compared with the less potent comparator compound. Deacetylation of FOX03a by SIRT2 has been shown to result in Skp2-mediated ubiquitination and degradation of FOX03a. A consistent response in terms of an increase in the levels of acetyl tubulin and FOX03a was observed in each of the four repeats of the experiment. The effects of the compound of example 1 on the proliferation of MCF-7 cells was also assessed (Peck, B., et al, Mol. Cancer Ther. 2010, 9, 844-855.). The results of the clonogenic assays are shown in Figure 7. Representative images of colonies after crystal violet staining are shown in Figure 7 (upper panel). The results shown in Figure 7, lower panel, represent an average of three independent experiments ± SD. Statistical significance was determined by Student's t-test (*P < 0.05; **P < 0.01; ***P < 0.01).

Consistently, in the clonogenic assays, the compound of example 1 was more effective in arresting cell proliferation compared to the comparator compound. The dose responses observed correlate with the biochemical SIRT2 inhibitory potency for these compounds, suggesting this effect is target mediated. Collectively, these data suggest that the compound of example 1 is a SIRT2 inhibitor in cells, and that it is even more potent than the previously reported comparator compound.

(f) Neuronal Cell Death Model

Parkinsonian neurodegeneration was modelled in vitro using a cell line of rat

mescenscephalic dopaminergic neurons treated with the irreversible proteasome inhibitor, lactacystin. The neuroprotective potential of the compound of example 1 was measured in the in vitro model of Parkinsonian neurodegeneration, using lactacystin to model Parkinsonian neuronal cell death in the N27 mescencephalic dopaminergic cell line (Adams, F. S.,

Neurochem. Res. 1996, 27, 619-627.)

An immortalised line of rat dopaminergic neurons, 1RB3 AN27 (N27), was maintained in RPMI 1640 medium supplemented with 10% foetal calf serum, 2 mM L-glutamine, 50 U/mL Penicillin and 50 μg/mL Streptomycin (henceforth termed 'complete medium') in a humidified incubator temperature controlled at 37 °C and with 5% C0₂ ventilation. Cells were seeded at 1 x 10⁴ cells/well in 96-well plates and left for 24 h to readopt their natural morphology. After this time, cell culture medium was replaced with fresh complete medium and cells were pre-treated for 48 h with the compound of example 1 at the indicated concentrations before addition of the irreversible proteasome inhibitor lactacystin (Enzo Life Sciences, UK) to give a final concentration of 0.75 μΜ, shown in preliminary experiments to result in -40-50% cell death in this cell line (data not shown). All cell treatments were run in triplicate. 24 h later cytotoxicity assays were performed. For performing the MTS (3-(4,5- dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt) assay the CellTiter 96^® AQ_ueous One Solution Cell Proliferation Assay Kit (Promega,

USA) was used as per the manufacturer's instructions. For performing the neutral red assay a previously published protocol was followed, Repetto et al {Nat. Protoc. 2008, 3, 1125-1131). The neutral red assay was followed sequentially by determination of total protein content in the same well as an additional endpoint measure of cell viability using a variation of the Bradford assay, Arranz et al, (Toxico. In Vitro, 1990, 4, 211-212). All data were expressed as a percentage of control wells treated with complete medium alone for each repeat and presented as mean ± SEM (n = 5). Statistical significance was tested using a one-way

ANOVA with post-hoc Tukey's multiple comparisons test. Results

The compound of example 1 mediated neuroprotection in the in vitro model of Parkinsonian cell death, as shown in Figure 8. Pretreatment of N27 cells for 48 h with the compound of example 1 prior to treatment with lactacystin resulted in a dose dependent increase in the absorbance reading at 490 nm wavelength in the MTS assay for cell viability, indicative of neuroprotection against lactacystin, and greater neuronal survival than vehicle-treated controls. This reached significance at 100 nM and 1 μΜ concentrations of the compound of example 1. Statistical significance ascertained from a 1-way ANOVA with post-hoc Tukey's multiple comparisons test is indicated with asterisks: *=p<0.05, **=p<0.01, ***=p<0.001, n=5 in Figure 8. The 1.45 μΜ dose, at which a significant effect (-23% neuroprotection) was observed, corresponds to the biochemical SIRT2 inhibitory potency and the cellular results obtained using MCF-7 cells {vide supra).

Claims

1. A compound of formula (I), or a salt thereof,

wherein:

A is -(CR⁹R¹⁰)m-; m is 0, 1, 2 or 3;

R¹ is selected from the group consisting of

R⁷R⁸ and -OCF₃;

B is -(CR^uR¹²)n- or -(CH2)_P-C(0)-(CH₂)_q-; n is 0, 1, 2 or 3; p and q are each independently 0, 1 or 2;

R² is selected from the group consisting of

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of

halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃, - R⁷R⁸, -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

and 3-10-membered heterocycle which is unsubstituted or substituted by

halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃; - R⁷R⁸; -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

R³ is selected from the group consisting of

hydrogen;

Ci-6alkyl which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of -F, -OH, -OCH₃, -OCF₃, NR⁷R and -CN; 3-10-membered carbocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi-4alkyl, -CN, -CF₃, R⁷R⁸ and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and

3-10-membered heterocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, -OCi-4alkyl, -CN, -CF₃, NR⁷R⁸ and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; R⁴ is hydrogen or -Ci-4alkyl; either R⁵ and R⁶ together are -CH2-CH2- so that together with the intervening atoms they form a 6-membered carbocycle, or R⁵ and R⁶ are each independently selected from the group consisting of H and -Ci-4alkyl; each R⁷ and R⁸ is independently selected from the group consisting of hydrogen and -C1-4- alkyl; and each R⁹, R¹⁰, R¹¹ and R¹² is independently selected from the group consisting of hydrogen, methyl and -CN; with the proviso that the compound is not 3-[(2-methoxy-l-naphthyl)methyl]-7-(3- pyridylmethylamino)-5,6,7,8-tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof, or 7- [(4-fluorophenyl)methylamino] -3 -(3 -quinolylmethyl)-5 , 6, 7, 8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof.

2. A compound as claimed in claim 1, wherein the compound has the formula (IB)

3. A compound as claimed in claim 1 or 2, wherein R³ is hydrogen.

4. A compound as claimed in any one of claims 1 to 3, wherein R⁴ is hydrogen.

5. A compound as claimed in any one of claims 1 to 4, wherein R¹ is 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃.

6. A compound as claimed in any one of claims 1 to 4, wherein R¹ is a 6-10 membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃.

7. A compound as claimed in any one of claims 1 to 4, wherein R¹ is unsubstituted Ci-6alkyl.

8. A compound as claimed in any one of claims 1 to 7, wherein A is -CH₂-. 9. A compound as claimed in any one of claims 1 to 8, wherein R² is a 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃.

10. A compound as claimed in any one of claims 1 to 8, wherein R² is a 5-10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃.

11. A compound as claimed in any one of claims 1 to 10, wherein B is -CH₂-. A compound as claimed in claim 1, wherein the compound has the formula (ID)

wherein:

R¹ is selected from the group consisting of unsubstituted Ci-6alkyl;

5- 10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃; and

6- 10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci_-4alkyl, -CF₃, -CN, -OCi_-4alkyl and -OCF₃;

R² is selected from the group consisting of

5- 10-membered aromatic heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen; -OH; -Ci_-4alkyl; -CF₃; -CN; -OCi_-4alkyl and -OCF₃; and

6- 10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or

3 substituents each independently selected from the group consisting of halogen; -OH; -Ci_-4alkyl; -CF₃; -CN; -OCi_-4alkyl and -OCF₃.

13. A compound as claimed in claim 12, wherein R² is a 6-10-membered aromatic carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -OH, -Ci-4alkyl, -CF₃, -CN, -OCi-4alkyl and - OCF₃.

14. A compound as claimed in claim 1, which is any one of the following compounds:

7-(benzylamino)-3-[(2-methoxy-l-naphthyl)methyl]-5,6,7,8-tetrahydrobenzothiopheno[2,3- d] pyrimidin-4-one;

3-[(2-methoxy-l-naphthyl)methyl]-7-(o-tolylmethylamino)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one;

7-[(3-fluorophenyl)methylamino]-3-[(2-methoxy-l-naphthyl)methyl]-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one;

3-[(2-methoxy-l-naphthyl)methyl]-7-[(3-methoxyphenyl)methylamino]-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one;

7-(2,2-dimethylpropylamino)-3-[(2-methoxy-l-naphthyl)methyl]-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one; and a compound of any one of Examples 11-44, or a salt thereof.

15. A compound which is

(7R)-3-[(2-methoxy-l-naphthyl)methyl]-7-(3-pyridylmethylamino)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof.

16. A compound which is

(7S)-3-[(2-methoxy-l-naphthyl)methyl]-7-(3-pyridylmethylamino)-5, 6,7,8- tetrahydrobenzothiopheno[2,3-d]pyrimidin-4-one or a salt thereof.

17. A compound as claimed in any one of claims 1 to 16, together with a further therapeutic ingredient, for simultaneous, sequential or separate administration.

18. A pharmaceutical composition which comprises: (i) a compound of formula (Γ), or a salt thereof,

wherein: A is -(CR^yR¹⁽V; m is 0, 1, 2 or 3;

R¹ is selected from the group consisting of

R⁷R⁸ and -OCF₃;

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3;

-OH, -OCi_-4alkyl, -OCF₃, - R⁷R⁸, -CN, and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and

3-10-membered heterocycle which is unsubstituted or substituted by 1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF_3;

-OH, -OCi_-4alkyl, -OCF₃, -NR⁷R⁸, -CN, and -Ci_-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

R² is selected from the group consisting of

3-10-membered carbocycle which is unsubstituted or substituted by

1, 2, or 3 substituents each independently selected from the group consisting of halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃, - R , -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

and 3-10-membered heterocycle which is unsubstituted or substituted by

halogen, -CF₃, -OH, -OCi_-4alkyl, -OCF₃; - R⁷R⁸; -CN;

-Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups;

R³ is selected from the group consisting of

hydrogen;

Ci-6alkyl which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of -F, -OH, -OCH₃, -OCF₃, NR⁷R⁸ and -CN;

3-10-membered carbocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, - OCi-4alkyl, -CN, -CF₃, N R and -Ci-4alkyl which is unsubstituted or substituted by 1 or 2 hydroxy groups; and

3-10-membered heterocycle which is unsubstituted or substituted by 1, 2 or 3 substituents each independently selected from the group consisting of halogen, -OH, - OCi-4alkyl, -CN, -CF₃, NR⁷R⁸ and -Ci-4alkyl which is unsubstituted or substituted by

1 or 2 hydroxy groups;

R⁴ is hydrogen or -Ci-4alkyl; either R⁵ and R⁶ together are -CH2-CH2- so that together with the intervening atoms they form a 6-membered carbocycle, or R⁵ and R⁶ are each independently selected from the group consisting of H and -Ci-4alkyl; each R⁷ and R⁸ is independently selected from the group consisting of hydrogen and -CM- alkyl; and each R⁹, R¹⁰, R¹¹ and R¹² is independently selected from the group consisting of hydrogen, methyl and -CN; and (ii) a pharmaceutically acceptable carrier.

19. A pharmaceutical composition as claimed in claim 18, wherein the composition comprises a further therapeutic agent. 20. A compound as defined in any one of claims 1 to 18, or a pharmaceutical composition as claimed in claim 18 or claim 19, for use as a medicament.

21. A compound as defined in any one of claims 1 to 18, or a pharmaceutical composition as claimed in claim 18 or claim 19 for use in the prevention or treatment of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect.

22. Use of a compound as defined in any one of claims 1 to 18 for the manufacture of a medicament for the prevention or treatment of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect. 23. A method of treating or preventing a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect in a mammal, which comprises administering to the mammal a therapeutically effective amount of a compound as defined in any one of claims 1 to 18, or of a pharmaceutical composition as claimed in claim 18 or claim 19. 24. A kit of parts comprising:

(a) a first pharmaceutical composition comprising a compound as defined in any one of claims 1 to 18, and a pharmaceutically acceptable carrier; and

(b) a second pharmaceutical composition comprising a further therapeutic agent, and a pharmaceutically acceptable carrier.

25. A compound as defined in any one of claims 1 to 18 which comprises an isotope atom, preferably a radioactive isotope atom.

26. Use of a compound as defined in any one of claims 1 to 18 or 25 as a reference compound in a method of identifying inhibitors of SIRT2.

27. A compound as defined in any one of claims 1 to 18 or 25 for use as a diagnostic agent for the diagnosis of a disease or disorder in which inhibition of SIRT2 provides a therapeutic or prophylactic effect.

28. A compound or pharmaceutical composition for use as claimed in claim 21, use of a compound as claimed in claim 22, a method as claimed in claim 23, or use of a compound as clamed in claim 27, wherein the disease or disorder is selected from the group consisting of a cancer, a metabolic disorder, an inflammatory disorder, a neurodegenerative disorder and a central nervous system disorder.

29. A compound or pharmaceutical composition for use as claimed in claim 21, use of a compound as claimed in claim 22, a method as claimed in claim 23, or use of a compound as clamed in claim 27, wherein the disease or disorder is selected from the group consisting of breast cancer, hepatocellular carcinoma, cervical cancer, liver cancer, brain cancer, kidney cancer, acute myeloid leukaemia, prostate cancer, pancreatic cancer, neuroblastoma, type II diabetes, pre-diabetes, insulin resistance syndrome, metabolic syndrome, high blood pressure, abnormal cholesterol levels, polycystic ovary syndrome, cardiovascular disease, vascular disease, hypercholesterolemia, obesity, dementia, Alzheimer's disease, Parkinson's disease and Huntington's disease.