Flavonoids from Hypericum Nagasawai Hayata

The whole herb of Hypericum subalatum Hayata contains three flavonoids, caffeic acid esters, a pyranoxanthone, and three xanthines, in addition to the previously reported xanthonolignoids. Among these compounds, 2,7‐dihydroxy‐3,4‐dimethoxyxanthone has not been described in the literature before. The co‐occurrence of xanthone derivatives and flavonoids in this plant is of chemotaxonomic significance.

Additional Constituents of Hypericum Subalatum

Chen

Kuoh

Wang

et al. 1989

The Constituents of Cynanchum Taiwanianum

Chen

Lai

Kao

1991

The isolation and identification of eleven crystalline components from the aerial part of Cynanchum taiwanianum Yamazaki (Asclepiadaceae) are described. Their structures were determined on the basis of spectral evidence and chemical transformation. Besides caffeic acid.ri-amyrin, and methyl phaeophorbide a, the isolated flavonoid components are classified into two groups, i.e. kaernpferol derivatives (kaempferol, astragalin, afzelin, trifolin) and quercetin derivatives (quercetin, isoquercitrin, quercitrin, hyperin). H lllUCO$yl rI1amnosyl galaclosyl J K

Chemical Constituents from the Root and Aerial Parts of Rosa taiwanensis

Yang

Fang

Cheng

1995

The-rootand aerial parts of Rosa taiwanensis Nakai contain the chemical constituents phenols, unsaturated acids, Ioliolide, abscisic acid, flavones, sterols, lupeol, betulin, betulinic acid, oleanolic acid and ursolie acid derivatives, Among them, 2a,3a-dihydroxyurs-12,19-dien-28-oic acid and its C-3 epimer are new compounds. ACKNOWLEDGMENTWe thank the National Science Council of the Republic of China for financial support.