[Studies on antibacterial constituents from the roots of Rubia cordifolia L].

Twelve compounds were isolated from the roots of Rubia cordifolia L.. Nine of them were established by chemical and spectroscopic methods to be alizarin (I),1-hydroxy-2-methyl-9,10-anthraquinone(II),1,3,6-trihydroxy-2-methyl- 9,10-anthra-quinone-3-O-(6'-O-acetyl)-alpha-L-rhamnosyl(1--- -2)-beta-D- glucoside(III),1,3,6-trihydroxy-2-methyl-9,10-anthraqueinone-3-O-a lpha- L-rhamnosyl(1----2)-beta-D-glucoside(IV),1,3,6-trihydrozy-2- methyl-9,10- anthraquinone-3-O-(6'-O-acetyl)-beta-D-glucoside(V),2-carbomethyoxy++ +-3-prenyl- 1,4-naphthohydroquinone di-beta-D-glucoside(VI),rubimallin(VII),beta- sitosterol(VIII) and daucosterol(IX), among them, V is a nwe compound and IX was obtained from this genus for the first time, III, VI and VII showed certain antibacterial activities.