Patent ID: 8084628

Claim:
A method for the treatment of cancer or a tumour mass, which comprises administering to a subject in need thereof a therapeutically effective amount of a compound of formula (I-b): wherein: R 1 is 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, halo, NR 10 R 11 , C 1-6 alkoxy, C 1-6 fluoroalkyl or C 1-6 alkyl; R 6 is hydrogen; R 7 is hydroxy or C 1-6 alkoxy; R 8 and R 9 are independently hydrogen, hydroxy, halo, NR 10 R 11 , C 1-6 alkoxy, C 1-6 fluoroalkyl or C 1-6 alkyl; and R 10 and R 11 are independently hydrogen, C 1-6 alkyl or trialkyl silyl.