Limonoids and alkaloids of the root bark of Dictamnus angustifolius

Six limonoids, limonin, limonin diosphenol, limonexic acid, obacunone, fraxinellone and fraxinellonone; nine alkaloids, dictangustine-A, iso-gamma-fagarine, dictamine, gamma-fagarine, skimmianine, isodictamine, isomaculosidine, N-methylflindersine and preskimmianine; five coumarins, angustifolin, umbelliferone, herniarin, scopoletin and scoparone; three steroids, sitosterol, stigmast-4-ene-3,6-dione and stigmast-4-ene-3-one, together with dictafolin-A and dictafolin-B were isolated from the root bark of Dictamnus angustifolius. Their structures were elucidated by spectral analysis. Among them, dictangustrine-A, iso-gamma-fagarine, dictafolin-A and dictafolin-B are reported for the first time from a natural source. (C) 1998 Elsevier Science Ltd. All rights reserved.