This invention relates to a method of preparing taxane derivatives of formula (VIII) by esterification of protected baccatin III or 10-deacetylbaccatin III by means of an acid of formula (VII), elimination of protection groupings and acylation of the amine function of the side chain. In formulae (VIII) and (VII): Ar stands for aryl, R.sub.3 is a trihalomethyl radical or phenyl substituted by a trihalomethyl radical, R.sub.4 is a hydrogen atom or is the same as R.sub.1. G.sub.1 and G.sub.2 are hydroxy protecting groups. ##STR1##