| abstract |
Cisapride, i.e. cis-4-amino-5-chloro-N-[1-[3-(4 fluoro-phenoxy)propyl]-3-methoxy-4-piperidinyl]-2-methoxy-benzamide, and similar benzamide derivatives, are prepared from novel 1-aryloxyalkyl- or 1-aralkyl-3-arylcarbonyloxy-4-oxo-piperidines, by nuclear substituent re arrangement involving acyl transfer under animal forming conditions, to give the corresponding 1-aryloxyalkyl- or 1-aralkyl-3-hydroxy-4-lower alkoxy-4-arylamido piperidine. This in turn is readily converted to the corresponding 3-oxo-4-arylamido-piperidine by reaction with strong organic acid, which can then be reduced, deprotected and 3-methylated to give the final compound, e.g. cisapride. |