Novel Derivatives Based on Zerumbone Scaffold as Potential Anticancer Inhibitors

A two-step procedure was applied to couple zerumbone, a natural sesquiterpene, with thiols 8a-k to obtain a small library of ten novel zerumbone derivatives 9a-k with full-length library data of spectra including ¹H-, ¹³C-NMR, and HRMS. The tautomerization of 9a, 9b, and 9c was revealed in DMSO and discussed in the case of 9c. The series of 9a-k together with zerumbone 1 was evaluated for their in vitro cytotoxic activity using three human cancer cell lines, HepG2, A549 and HeLa. The results revealed that all zerumbone derivatives had cytotoxic activity against HepG2, A549, and HeLa cells that was 4-20 times stronger than zerumbone.