Studies with plant-cell cultures of the Chinese herbal plant, Tripterygium wilfordii. Isolation and characterization of diterpenes†

A detailed analysis of the established cell-culture line (coded as TRP4a) of the important Chinese herbal plant, Tripterygium wilfordii, in terms of diterpene production, is presented. In this study, 28 diterpenes have been isolated and characterized. Of these, 26 were isolated for the first time from the TRP4a cell line, 8 were novel compounds. From an analysis of the diterpenes obtained, a biosynthetic pathway of the pharmacologically interesting triepoxide, tripdiolide 29, is proposed.