New Toxic Metabolites From A Mushroom, Hebeloma Vinosophyllum. Ii.1) Isolation And Structures Of Hebevinosides VI, VII, VIII, IX, X, and XI

Abstract

Four new triterpene glycosides, hebevinosides VI, VII, VIII, and IX, whose common aglycone is 3β,7β, 16β-trihydroxycucurbita-5,24-diene (hydroxyhebevinogenin), have been isolated from the acetone extract of a poisonous mushroom, Hebeloma vinosophyllum, and deduced to have the structures of 3,β7β, 16β-trihydroxycucurbita-5,24-diene-3-O-β-D-xylopyranoside-16-O-/β-D-glucopyranoside, 3β,7β, 16βtrihydroxycucurbita-5,24-diene-3-O-β3-D-xylopyranoside-16-0-(4,6-di-O-acetyl)β-D-glucopyranoside, 3β7β16β-trihydroxycucurbita-5,24-diene-3-O-(4-O-acetyl)-β-D-xylopyranoside-16-O-(4,6-di-O-acetyl)-β-D-glucopyranoside, and 3β,7β, 16β-trihydroxycucurbita-3-O-β-D-xylopyranoside, respectively. Two new glycosides, hebevinosides X and XI, whose common aglycone is 3β,16β-dihydroxy-7β-methoxycucurbita-5,24-diene (methoxyhebevinogenin), have also been isolated from the aqueous methanolic extract of the mushroom in addition to hebevinosides I, II, III, IV, and V previously reported, and deduced to be 3β, 16/β-dihydroxy-7β-methoxycucurbita-5,24-diene-3-β-β-D-xylopyranoside-16-0β-D-glucopyranoside and 3β,16β-di-hydroxy-7β-methoxycucurbita-5,24-diene-3-O-β-D-xylopyranoside-16-O-(4,6-di-O-acetyl)- β-D-glucopyranoside, respectively. Among these eleven hebevinosides, I, IV, V, X, and XI, whose common aglycone is methoxyhebevinogenin, have been proved to be artifacts formed from the genuine metabolites III, IX, II, VI, and VII, whose common aglycone is hydroxyhebevinogenin, during extraction of the mushroom with aqueous methanol, respectively, and VIII, whose aglycone is hydroxyhebevinogenin, has also been proved to be a genuine metabolite of this mushroom. The relationship between the structure and toxicity of hebevinosides was also investigated. © 1987, The Pharmaceutical Society of Japan. All rights reserved.