Saponin and Sapogenol. X. Structures of Jegosapogenin and Desacyljegosaponin obtained from Pericarps of Styrax japonica SIEB. et ZUCC.

The full detail of the chemical evidence on the structure of jegosapogenin (=21-O-tigloyl-barringtogenol C (Ia)), which was obtained along with barringtogenol C (I) and barringtogenol D (II) by acid hydrolysis of the pericarps saponin (=jegosaponin) of Styrax japonica SIEB. et ZUCC. (Styracaceae), is described. The structure of desacyl-jegosaponin, which is a common desacylated product of the saponin constituents of jegosaponin, and was prepared in a high yield by alkaline treat-ment of jegosaponin, has been established as barringtogenol C (3)-[β-D-glucopyranosyl-(1glu→2glr)][α-L-rhamnopyranosyl (1rham→2gal)-β-D-galactropyranosyl (1gal→4glr)]-β-D-glucuronopyranoside (VIf) on the basis of the chemical and physicochemical evidence.