Additional Bioactive Silvestrol Analogs from the Roots of Collected in Vietnam.

The tropical plant is known to produce cyclopenta[]benzofuran and other types of rocaglate derivatives including silvestrol () and 5‴-episilvestrol () that are of current pharmacological interest. In the present work, further investigation of roots collected in Vietnam has yielded two new rocaglate acetonide derivatives ( and ) and a known pentanor-3,4--dammarane triterpenoid () found for the first time as a natural product, in addition to four known rocaglates (-). The structures of compounds and were confirmed by partial synthesis experiments, and their potential occurrence as extraction artifacts was investigated by targeted selective ion monitoring using UHPLC-MS. All compounds obtained were evaluated against a panel of four human cancer cell lines, in which the six rocaglate derivatives (-) tested all showed submicromolar potencies.