Synthesis of a [3H]-labelled derivative of the microtubular poison taxol

A labelled derivative of the microtubule poison taxol has been developed on acetylation of the 7-OH function of taxol with [3H] acetic anhydride. The [3H] 7-acetyl taxol synthesized was chemically and radiochemically pure and has not undergone radiolysis during 1.5 years. This compound was also stable in the presence of microtubule proteins. The ID50 of 7-acetyl taxol for stabilization of microtubules was two times the ID50 of taxol. Hence it can be used as a probe for biological studies. The acetylation of the hydroxyl group at position C-7 is a general method applicable to other taxol derivatives as starting compounds.