文摘
Protoapigenone (1), isolated from Thelypteris torresiana, previously showed significant cytotoxic activityagainst five human cancer cell lines. In a continued structure-activity relationship study, the first totalsynthesis and modification of 1 were achieved. All synthesized compounds and related intermediates wereevaluated for cytotoxic activity against five human cancer cell lines, HepG2, Hep3B, MDA-MB-231, MCF-7, and A549. Among them, 24 showed 2.2-14.2-fold greater cytotoxicity than 1 and naphthyl A-ringanalogues remarkably enhanced the activity.