DERIVATIVES OF VARIOLIN B

摘要

The invention provides antitumour compounds of formula (I), wherein R¹ is an aromatic substituent; R² is hydrogen or a substituent when the dotted line is absent, or R² is absent when the dotted line represents a bond to give a double bond between the nitrogen which bears R² and the carbon which bears R³; R³ is an oxo group -O when the dotted line is absent or is a substituent when the dotted line represents a bond to give a double bond between the nitrogen bearing R² and the carbon bearing R³; R⁴ is hydrogen or a substituent; and pharmaceutically acceptable salts thereof.