| abstract |
There is provided a process for preparing cephalotaxine esters corresponding to the following general formula I, which comprises the cephalotaxine backbone, and that can be written as C(R 1 )(R 2 )(XH)COO[CTX], wherein CTX represents the cephalotaxine backbone, being optionally substituted, the process consisting in bringing the corresponding cephalotaxine compound, or salts, isomers or tautomeric forms thereof, which is free or which is in the form of a metal alkoxide CTXOM, into contact with a heterocyclic side chain precursor having both a bifunctional protected (bidentate) and activated (acylating) form of an acid bearing a hydrogenated heteroatom, in the alpha (α) position with respect to the carboxyl group, and corresponding to the following general formula: n n n n n n n n n n in a customary aprotic solvent, preferably with a catalyst which may be a hindered tertiary amine, at a temperature of between −80° C. and +100° C., preferably in the range 0 to 30° C. |