Three new taxane diterpenoids from seeds of the Chinese yew, Taxus yunnanensis and T. chinensis var. mairei.

Three new taxane diterpenoids were isolated from the seeds of the Chinese yew, Taxus yunnanensis Cheng et L. K. Fu and T. chinensis var. mairei Cheng et L. K. Fu. The structures were established as 1beta,10beta-dihydroxy-9alpha,13alpha-diacetoxy-5alpha-(3'-dimethylamino-3'-phenyl)-propionyloxytaxa-4(20),11-diene, 5alpha-hydroxy-9alpha,100,13alpha-triacetoxy-11(15-->1)abeotaxa-4(20),11-di-ene, and 5alpha,13alpha-dihydroxy-9alpha,10beta-diacetoxy-11 (15-->1 )abeo-taxa-4(20),11-diene on the basis of 1D, 2D NMR, and mass spectral analysis.