Effective irreversible alkylating reagents based on the structure of clavulones

We describe the design and synthesis of alkylating reagents based on the structure of clavulones. They are composed of cross-conjugated dienone system and irreversibly reacted with two nucleophiles under mildly basic conditions via β-elimination. Hydroxyl derivative 7b showed the highest reactivity toward thiols and showed the strongest cytotoxicity in Hela S3 cells among the three derivatives having a different protecting group at the tert-hydroxyl group.