Taxane diterpenoids from Taxus yunnanensis and Taxus cuspidata

Chemical examination of the seeds of the Chinese yew, Taxus yunnanensis Che ng et L. K. Fu and the Japanese yew, Taxus cuspidata Sieb et Zucc, resulted in the isolation of four taxane diterpenoids. The structures of these taxo ids were established as (12 alpha)-2 alpha-acetoxy-5 alpha,9 alpha,10 beta- trihydroxy-3,11-cyclotax-4(20)-en-13-one; 2 alpha,7 beta,13 alpha-triacetox y-5 alpha,9 alpha-dihydroxy-2(3 --> 20)abeotaxa-4(20),11-dien-10-one; 9 alp ha,10 beta-diacetoxy-5 alpha-cinnamoyloxytaxa-4(20),11-dien-13 alpha-ol and the known 2 alpha,7 beta,9 alpha,10 beta,13-pentaacetoxytaxa-4(20),12-dien e-5 alpha,11 beta-diol on the basis of spectral analysis. (C) 2000 Elsevier Science Ltd. All rights reserved.