摘要 |
The invention provides antitumour compounds of formula (I), wherein R<SUP>1 </SUP>is an aromatic substituent; R<SUP>2 </SUP>is hydrogen or a substituent when the dotted line is absent, or R<SUP>2 </SUP>is absent when the dotted line represents a bond to give a double bond between the nitrogen which bears R<SUP>2 </SUP>and the carbon which bears R<SUP>3</SUP>; R<SUP>3 </SUP>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 R<SUP>2 </SUP>and the carbon bearing R<SUP>3</SUP>; R<SUP>4 </SUP>is hydrogen or a substituent; and pharmaceutically acceptable salts thereof. |