Isoflavonoids of yellow lupin. Part II. New 5-O-methylisoflavones in the roots of yellow lupin (Lupinus luteus L. cv. Barpine).

In addition to 5-0-methylgenistein (1), a further investigation of the isoflavonoid constituents in roots of the yellow lupin {Lupinus luteus L. cv.Barpine) has yielded five new 5-0methylisoflavones named barpisoflavone A (2), 5-0-methyl-lupiwighteone (3), barpisoflavone B (4), 5-0-methylderrone (5) and barpisoflavone C (6).These isoflavones were identified by physicochemical methods involving the use of other lupin isoflavones as reference compounds.