Clionasterol Glucoside and Acylated Clionasterol Glucosides from Oplismenus burmannii

Abstract

AbstractA new clionasterol glucoside, clionasterol‐[(1'→3α)‐O‐β‐D]‐glucopyranoside (1), a new acylated clionasterol glucoside, clionasterol‐[6'‐O‐acyl‐(1'→3β)‐O‐b‐D]‐glucopyranoside (2) and clionasterol (3) were isolated from the aerial parts of Oplismenus burmannii. The nature and length of fatty acid acyl chains in 2 was identified by alkaline methanolysis of compound 2. The aglycone fraction on GC‐MS analysis showed three peaks in GC at tR 49.86 (82.1%), 51.13 (13.3%) and 56.53 (4.6%) min, which were characterized as arachidic acid methyl ester (a) oleic acid methyl ester (b) and 12‐methyltetradecanoic acid methyl ester (c) respectively. Thus 2 was characterized as a mixture of three new compounds, clionasterol‐[6'‐O‐eicosanoyl‐(1'→3β)‐O‐β‐D]‐glucopyranoside (2a), clionasterol‐[6'‐O‐(8Z)‐octa‐deca‐9‐enoyl‐(1'→3β)‐O‐β‐D]‐glucopyranoside (2b) and clionasterol‐[6'‐O‐(12‐methyltetradecanoyl)‐(1'→3β)‐O‐β‐D]‐glucopyranoside (2c).