Three new diarylheptanoid glycosides from Alnus japonica

Abstract

Two new diarylheptanoid glycosides, hirsutanonol 5-O-(6-O-galloyl)-β- D-glucopyranoside and 3-deoxohirsutanonol 5-O-β-D-glucopyranoside, were isolated from fresh leaves of Alnus japonica together with three known diarylheptanoids [hirsutanonol, hirsutanonol 5-O-β-D-glucopyranoside and hirsutenone], five known triterpenes [β-amyrin, 3-O-acetyl-β-amyrin, 3-O- acetyltaraxerol, glutinone and lupenone] and quercitrin. One more new diarylheptanoid glycoside, 3-deoxohirsutanonol 5-O-(6-O-β-D-apiosyl)-β-D- glucopyranoside, was also isolated from bark together with 3- deoxohirsutanonol 5-O-β-D-glucopyranoside, two known diarylheptanoids [hirsutoside and hirsutanonol 5-O-β-D-glucopyranoside] and four known triterpenes [glutinol, glutinone, lupenone and taraxerone]. Their structures were determined on the basis of spectroscopic and chemical evidence.