Patent ID: 6180802
Filing Date: 2001-01-30
Classification: C07D,C07F

Abstract:
A process for the preparation of a 7-(.beta.-substituted-alkoxycarbonyloxy)-10-hydroxytaxane derivative corresponding to the formula 3b: ##STR14##in whichR.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6 and R.sub.14 are each the same or different and each represents a radical Q, wherein:Q is H, OH, R, OR, SH, SR, OCOR, OCOOR, HCO or X, whereinX is a halogen atom, andR represents a linear or branched alkyl, alkenyl or alkynyl radical, a perhaloalkyl radical, a linear or branched heteroalkyl, heteroalkenyl or heteroalkynyl radical, a cycloalkyl or cycloalkenyl radical, a heterocycloalkyl or heterocycloalkenyl radical, an aryl radical or an aralkyl radical, wherein said radicals are unsubstituted or substituted; andR.sub.7 represents an alkoxycarbonyl group substituted at the 2-position which is more hindered than 2,2,2-trichloroethoxycarbonyl and which is removable by a .beta.-elimination mechanism,wherein said process comprises the slow addition, at a temperature greater than room temperature, of the alkoxycarbonyl chloride substituted at the 2-position corresponding to the alkoxycarbonyl group at R.sub.7, diluted in an appropriate solvent, to a vigorously stirred solution of the 7-10-dihydroxytaxane of general formula 3a ##STR15##in which R.sub.1, R.sub.2, R.sub.4, R.sub.5, R.sub.6 and R.sub.14 are as defined above, in the presence of pyridine and/or of a hindered substituted pyridine.