Patent ID: 7144886

Claim:
A compound according to general formula 1 or a pharmaceutically acceptable salt thereof, wherein: R 1 is H or CN, R 2 is selected from CH 2 R 5 , CH 2 CH 2 R 5 and C(R 3 )(R 4 )—X 2 —(CH 2 ) a R 5 , R 3 and R 4 are each H; R 5 is selected from N(R 8 )C(═O)R 9 , N(R 8 )C(═S)R 9 and N(R 8 )R 10 ; R 8 is H; R 9 is R 11 (CH 2 ) b ; R 10 is R 11 (CH 2 ) b ; R 11 is heteroaryl; R 12 is R 19 OC(═O); R 19 is R 20 C(═O)OC (R 21 )(R 22 ); R 20 , R 21 and R 22 are each independently selected from H and lower alkyl (C 1 –C 6 ); X 1 is CH 2 , X 2 is CH 2 ; a is 1, 2 or 3 and b is 0–3.