UNUSUAL FLAVONOIDS FROM LONCHOCARPUS-OROTINUS SEEDS

Seeds of Lonchocarpus orotinus have yielded five flavonoids the identities of which have been elucidated by spectroscopic analysis. In addition to the known minimiflorin three novel flavonoids, characterized by the presence of 2'',6''-dihydroxy substitution of the B-ring, were isolated and identified as orotinin (6''-hydroxyminimiflorin), orotinin-5-methyl ether and orotinichalcone. A further compound, which was obtained only in a mixture with orotinin-5-methyl ether, was tentatively identified as the 4,6''-epoxy derivative of the flavan-4-ol of the orotinin series.