Toyokichi Yoshizawa

Antioxidant xanthones from Garcinia subelliptica

Abstract From the woods of Garcinia subelliptica four new xanthones, garciniaxanthone C, 1,2,5-trihydroxyxanthone, 2,6-dihydroxy-1,5-dimethoxyxanthone and 1,2-dihydroxy-5,6-dimethoxyxanthone have been isolated along with a new benzophenone derivative, 4′,6-dihydroxy-2,3′4-trimethoxybenzophenone. Their structures have been determined on the basis of mainly spectroscopic data and some chemical reactions. Antioxidative properties of all the isolated xanthones have been evaluated in vitro using three assay systems to measure antilipidperoxidation, free radical and superoxide anion scavenging activity.

Butanoic acid glucoside composition of whole body and in vitro plantlets of Anoectochilus formosanus

Abstract A butanoic acid glucoside, 3- O - β - D -glucopyranosyl-(3 R )-4-dihydroxy butanoic acid, with known aliphatic glucosides were isolated from the methanol extract of dried whole plants of Anoectochilus formosanus Hay. Butanoic acid glucosides were formed in 3 types of regenerated plantlets in vitro .

A novel macrocyclic spermine alkaloid from Incarvillea sinensis.

A novel macrocyclic spermine alkaloid incasine C′ (1), along with a known compound incasine C (2), were isolated from the whole plants of Incarvillea sinensis, and their structures were elucidated on the basis of chemical and spectroscopic evidence.