Patent ID: 7601855

Claim:
A compound of the general formula (I-b): wherein: R 1 is hydroxy, halo, C 1-6 alkoxy or C 1-6 alkyl; the drawing and R 2 together represent a double bond or the drawing represents a single bond and R 2 is hydrogen or hydroxy; R 3 , R 4 , and R 5 , are independently hydrogen, hydroxy, NR 10 R 11 , C 1-6 alkoxy or C 1-6 alkyl; R 6 is hydrogen, hydroxy, halo, C 1-6 alkoxy or C 1-6 alkyl; R 7 is hydroxy or C 1-6 alkoxy; R 8 and R 9 are independently hydrogen, hydroxy, halo, C 1-6 alkoxy or C 1-6 alkyl; and R 10 and R 11 are independently hydrogen, C 1-6 alkyl or trialkyl silyl; or a pharmaceutically acceptable salt thereof.