Steroidal alpha-methylene delta-lactones as potential antitumor agents.

Four novel steroidal alpha-methylene delta-lactones have been synthesized and shown to be active against human nasopharyngeal carcinoma (KB) cells in culture. The syntheses involved the use of known alpha-methylenation procedures. In addition, the lactone 6 was directly methylenated by reaction with CH2O/KOH or Et2NH/CH2O/Et2NH.HCl. The formation of a cysteine adduct (15) with the alpha-methylene lactone 10 is reported.