万年青の成分 (第2報)

Rhodexin Aの構造に就いて

抄録

Rhodexin A resists hydrolysis under mild conditions but submits to hydrolysis with diluted alcohol containing 3.4% of hydrochloric acid to yield β-anhydrorhodexigenin A, identical with α-anhydrosarmentogenin. The sugar obtained by the hydrolysis of rhodexin A was found to be rhamnose from paper partition chromatogram and the phenylosazone. Since rhodexin A yields an iso compound with negative Legal reaction by the action of alkali, it was assumed to possess a tertiary hydroxyl group in C₁₄-position. From these results, rhodexin A is assumed to be a glycoside composed of sarmentogenin as an aglycone and rhamnose as its sugar.