Studies on Taxol® Biosynthesis. Preparation and Tritium Labeling of Biosynthetic intermediates by Deoxygenation of a Taxadiene Tetra-acetate Obtained from Japanese Yew.

Taxa-4(20),11(12)-diene-5α-acetate 5 and Taxa-4(20), 11(12)-diene-5α-acetate, 10β-ol 6, have been identified as early stage intermediates involved in the biosynthesis of Taxol® (paclitaxel). Tritium-labeled 5 and 6 were successfully prepared by Barton deoxygenation using tri-n-butyltintritiide of the C-14-hydroxyl group of a taxoid obtained from Japanese Yew.