Flavonoids from the stem bark of Millettia hemsleyana

The stem bark of Millettia hemsleyana has yielded six simple flavonoids of which three are novel. Dihydromilletenone methyl ether and dihydroisomilletenone methyl ether represent the two keto—enol tautomers of the known β-hydroxychalcone milletenone, trapped by methylation and reduction, and the third new compound, 3′,4′-methylenedioxy-7-methoxyflavone, is the cyclized form of a demethylated milletenone. All compounds were identified on the basis of detailed spectral analysis.