Patent ID: 7452894

Claim:
Use of a compound of formula (I) or a pharmaceutically acceptable salt thereof: wherein R 1 is selected from alkyl, aryl, alkoxy, aryloxy, alkylthio, arylthio, CN, halo, NR 5 R 6 , NR 4 COR 5 , NR 4 CONR 5 R 6 , NR 4 CO 2 R 7 , and NR 4 SO 2 R 7 ; R 2 is selected from N, O or S-containing heteroaryl groups, wherein the heteroaryl group is attached via an unsaturated carbon atom of said heteroaryl group which is adjacent to one or two N, O, or S-heteroatom(s), other than heteroaryl groups substituted at both positions adjacent the point of attachment of the heteroaryl group to the purine moiety; R 3 is selected from H, alkyl, COR 8 , CONR 9 R 10 , CONR 8 NR 9 R 10 , CO 2 R 11 , and SO 2 R 11 ; wherein: alkyl is substituted by a substituent R 12 , wherein R 12 is selected from the group consisting of hydroxy, alkoxy, dialkylamino, NH 2 , aryloxy, CN, halo, cycloalkyl, Ar(R 18 ) a (R 19 ) b (R 20 ) c , non-aromatic heterocyclyl, CO 2 R 13 , CONR 14 R 15 , CONR 8 NR 9 R 10 , C(═NR 13 )NR 14 R 15 , NR 13 COR 14 , NR 13 CO 2 R 11 , trialkylsilyl, and phthalimido, wherein: (a) R 13 , R 14 and R 15 are selected from the group consisting of hydrogen, alkyl, and aryl, or (b) where R 14 and R 15 are in an (NR 14 R 15 )group, R 14 and R 15 may be linked to form a heterocyclic ring; Ar is an aryl group; R 18 , R 19 and R 20 are selected from NR 5 R 6 , substituted alkyl, alkoxy, halogen, NO 2 , CN, hydroxy, NHOH, CHO, CONR 5 R 6 , CO 2 R 5 , NR 4 COR 5 , NR 4 CO 2 R 7 , NR 4 SO 2 R 7 , OCO 2 R 7 and aryl; and a, b and c are 0 or 1 such that a+b+c≧1; R 4 , R 5 and R 6 are independently selected from H, alkyl, and aryl, or where R 5 and R 6 are in an (NR 5 R 6 ) group then R 5 and R 6 may be linked to form a heterocyclic ring; R 7 is alkyl or aryl; R 8 , R 9 and R 10 are independently selected from H, alkyl, and aryl, or R 9 and R 10 may be linked to form a heterocyclic ring, or where R 8 , R 9 , and R 10 are in a (CONR 8 NR 9 R 10 ) group, R 8 and R 9 may be linked to form a heterocyclic group; wherein said heterocylic ring or group is a saturated, partially unsaturated or aromatic 5, 6 or 7 membered ring optionally containing one or more further heteroatoms selected from N, O and S; and R 11 is alkyl or aryl, other than compounds wherein R 3 is H, R 1 is NH 2 and R 2 is thienyl.