Benzoxazinoid and indoxyl glycosides from Wrightia religiosa

Abstract

A new class of secondary metabolites of the family Apocynaceae, benzoxazinoid, was reported for the first time from Wrightia religiosa. A new benzoxazinoid glycoside, (2S)-2-O-β-d-glucopyranosyl-2H-1,4-benzoxazin-3(4H)-one (2) and a new indole diglycoside, indoxyl 3-O-β-d-apiofuranosyl-(1 → 6)-β-d-glucopyranoside (4) were isolated, together with twelve known compounds, including benzoxazinoid glycosides (1, 3), simple aromatic glycosides (5–8), a lignan glycoside (9), flavonol glycosides (10–13) and a megastigmane glucoside (14). The structure elucidation of these compounds was based on analyses of physical and spectroscopic data including 1D and 2D NMR experiments. A benzoxazinoid with (2S)-configuration was isolated for the first time from natural source.