Passerini multicomponent reaction of protected alpha-aminoaldehydes as a tool for combinatorial synthesis of enzyme inhibitors

Three-component Passerini condensation of N-Boc-alpha-aminoaldehydes with various isocyanides and carboxylic acids leads, after Boc-deprotection/transacylation, to complex peptide-like structures containing an alpha-hydroxy-beta-aminoacid unit or, after oxidation, an alpha-oxo-beta-aminoacid unit.