Brassinolide-related new bioactive steroids from Dolichos lablab seed.

Since the discovery of brassinolide (1),1} new brassinolide analogs, dolicholide (2)2) and castasterone (3)3) have been isolated from immature seeds of Dolichos lablab and chestnut gall, respectively.The occurrence of 1 and 3 in Chinese cabbage4) and other plant sources5) has also been demonstrated.Recently, two additional analogs were isolated from the Dolichos seeds, with which the present paper is concerned.The crude extract of the immature seeds (34kg) was first purified by silica gel chromatography.Elution with chloroform-methanol mixtures afforded two active fractions, namely