Three new rearranged taxane diterpenoids from the bark of Taxus chinensis var. mairei and the needles of Taxus cuspidata

Three new rearranged taxane diterpenoids with 5/7/6-membered ring system we re isolated from the bark of Taxus chinensis var, mairei (1 and 2) and the needles of T. cuspidata (3). The structures of them were established as 2 a lpha,7 beta-diacetoxy-5 alpha, 10 beta, 13 alpha, 15-tetrahydroxy-4 beta (2 0)-epoxy-9 alpha-benzoyloxy 11(15-->1)abeotax-11-ene (1), 2 alpha,4 alpha-d iacetoxy-7 beta-benzoyloxy-5 beta,20-epox 10 beta, 13 alpha,15-tetrahydroxy -11 (15-->1)abeotax-11-ene (2), and 4 alpha, 7 beta-diacetoxy-2 alpha-benzo yloxy-5 beta,20-epoxy-9 alpha, 10 beta, 13 alpha, 15-tetrahydroxy-11(15-->1 )abeotax-11-ene (3) on the basis of spectral data including 2D NMR spectros copies.