Withalutin, a new cytotoxic withanolide from Athenaea velutina (Sendtn.) D'Arcy.

Bioassay-guided fractionation of dichloromethane extract from leaves led to the isolation of three withanolides, all being reported for the first time in this species. They were identified as withacnistin (), withacnistin acetate () and a new withanolide, designated as withalutin (). The structures were established by spectral data analysis, including MS, 1D and 2D NMR. In addition, ADMET studies were employed to understand the pharmacokinetic properties of these withanolides. The withanolides isolated from reduced cancer cell viability with IC values ranging from 1.52 to 5.39 µM. prediction revealed that withanolides have good gastrointestinal absorption or oral bioavailability properties; and are not likely to be mutagenic or hepatotoxic. These findings revealed that is an important source of cytotoxic withanolides.