| abstract |
[PROBLEMS] To provide a simple and practical method for producing taxol A, B or C. The method comprises: (i) taxol homolog A, B or C is separated from Taxi baritiana bark and (ii) treated with periodate in an acid-free polar solvent to split the diol to dialdehyde at room temperature; (Iii) reduction to acetal with borohydride in polar solvent-acetic acid medium, and (iv) acidification to the intermediate 10-deacetyltaxol A, B or C with a mixture of mineral acid-polar solvent, (v) Reacting with silane in the presence of a base to protect the 2 ', 7-hydroxyl group and (v i) the 10-hydroxyl group is acetylated in situ with an acetylating agent, and (vii) the 2 ', 7-hydroxyl group is deprotected with a mineral acid-polar solvent mixture, (vii) i) Taxol A or B or C is isolated by chromatography on silica. |