N-demethylation of cyamemazine via non-classical Polonovski reaction and its conjugation to bovine serum albumin.

A modified Polonovski reaction has been employed to obtain the N-demethylated metabolite of the neuroleptic drug cyamemazine. The synthesis involves N-oxide formation, isolation of the corresponding N-oxide, and a FeSO(4)·7H(2)O mediated Polonovski reaction to afford the desired monodesmethyl cyamemazine. In a subsequent step the hapten N-demethylcyamemazine-hemiglutarate was synthesized and its conjugated to bovine serum albumin (BSA).