Studies on the Himalayan yew Taxus wallichiana: Part VII - The taxoids andphenolic constituents of the roots of Taxus wallichiana

The systematic investigation on the roots of Taxus wallichiana has resulted in the isolation of nine taxoids-taxol 1 baccatin III 2, baccatin IV 3, ta xusin 4, a C-14 oxygenated taxoid 5, 1 beta-hydroxybaccatin I 6, pentaaceto xy taxadiene 7, a dibenzoylated rearranged taxoid 8, 7-xylosyl-10-deacetyl- taxol C 9 and three phenolic compounds (-) seco-isolariciresinol 11, taxire sinol 12 and isotaxiresinol 13. The compounds have been characterized on th e basis of their spectral characteristics. The occurrence of taxoid 9 in th e roots of the plant is quite significant. The distribution of the above co mpounds in other parts of the plant are also summarized.