Process for preparing dipeptidyl peptidase IV inhibitors and intermediates therefor

摘要

A process for production of cyclopropyl-fused pyrrolidine-based inhibitors of dipeptidyl peptidase IV is provided which employs a BOC-protected amine of the structure prepared by subjecting an acid of the structure to reduce amination by treating the acid with ammonium formate, nicotinamide adenine dinucleotide, dithiothreitol and partially purified phenylalanine dehydrogenase/formate dehydrogenase enzyme concentrate (PDH/FDH) and without isolating treating the resulting amine of the structure 2 with di-tert-butyl dicarbonate to form the BOC-protected amine.