[Studies of the mechanism of 7-epi-taxol converted to taxol from Taxus extract catalyzed with Al2O3].

Under the catalysis of Al2O3, 7-epi-taxol in Taxus yunnanensis extract could convert to taxol. The factors including the concentration of CH3OH in the mobile phase, the type of Al2O3 and the reaction time could influence the isomeric reaction. The catalysis mechanism fo Al2O3 was investigated. The isomerization of 7-epi-taxol was under the cooperation of the Lewis souci activity core and the basic activity core in the surface of Al2O3 at room temperature. The type and strength of activity core controlled the procedure of reaction, and the suitable content of CH3OH in the mobile phase would accelerate the reaction.