| abstract |
Compounds of the formula (II):n n or acid addition salts thereof, wherein R¹ is hydrogen, C₁₋₆ alkyl or C₁₋₄ alkyl substituted by halo or C₁₋₄ alkoxy, R² is C₁₋₄ alkyl or C₁₋₄ alkyl substituted b halo or C₁₋₄ alkoxy, R³ is C₁₋₄ alkyl nor C₁₋₄ alkyl substituted by halo or C₁₋₄ alkoxy orn n forms a C₅₋₇ cycloalkyl or cycloalkenyl group and R⁴ is hydrogen or C₁₋₄ alkyl are described as useful medicaments in the treatment of cancer. Pharmaceutical compositions containing the compounds and their manufacture are also disclosed. |