Sterols from a Vietnamese Wood-Rotting Phellinus sp.

Abstract

Phytochemical examination of the methanolic extract from fruit bodies of an unidentified Vietnamese Phellinus species led to the isolation of four compounds, one of which is a new steroid, 25-hydroxy-ergosta-7,24(28)-dien-3β -ol, named phellinol, together with senexonol, trametenolic acid B and ergosta-4,6,8(14),22-tetraen-3-one. Their structures were determined by 2D NMR, MS, IR and UV spectroscopy. In addition, the absolute configuration of senexonol was established by X-ray crystallographic analysis of its p-bromobenzoate derivative as 22(R)-hydroxy-4(S),14(S)- dimethyl-cholesta-8,24-dien-3-one. All compounds moderately suppressed the lipopolysaccharide (LPS)-induced production of nitric oxide (NO) in RAW 264.7 cells.