ISOLATION AND IDENTIFICATION OF FOUR NEW TETRACYCLIC ATXANES FROM TAXUS YUNNANENSIS

Four new minor toxoids, named as taxayuntin A, B, C and D, have been isolated from the ethanolic extract of the bark of Taxus yunnanensis Cheng et L.K.Fu. Their structures were identified as the new taxane diterpenoids with 5/7/6/4 membered ring system by spectral means and 2D NMR shift correlation experiments.