Rotenoids from roots of Clitoria Fairchildiana.

A new rotenoid, named 9-demethylclitoriacetal, together with the known compounds, 11-deoxyclitoriacetal, 6-deoxyclitoriacetal, clitoriacetal and stemonal, was isolated from roots of Clitoria fairchildiana. Its structure was elucidated as 6a,12a-dihydro-6,9,11,12a-tetrahydroxy-2,3-dimethoxy-[1]benzopyrano[3,4-b] [1]benzopyran-12(6H)-one (1), on the basis of spectroscopic and chemical evidence.