| abstract |
A method of acylating C-2' O-protected-10-hydroxy taxol selectively at the C-10 hydroxyl position over the C-7 hydroxy position thereof to produce C-2' O-protected taxol is accomplished first by dissolving C-2' O-protected-10-hydroxy taxol in an acceptable ether solvent therefor, such as tetrahydrofuran, to form a first solution at a first temperature. The first solution is then cooled to a second temperature, and a lithium base, preferably n-butyl lithium, is added to form an intermediate compound having a lithium alkoxide at the C-10 position thereof. An acylating agent, such as acetyl chloride, is then added. The resulting solution may be quenched, for example with ammonium chloride, to eliminate excess of the acylating agent and the lithium base. The result is a solution containing C-2' O-protected taxol. This solution may then be washed, concentrated and purified. The present invention is also directed to C-10 lithium alkoxide intermediate compounds for the production of paclitaxel. |