novel N-(protected α-tri-, tetra- and pentapeptidoyl)benzotriazoles couple in aqueous acetonitrile solution at 0 ˚C with free amino acids, dipeptides, and tripeptides to afford N-terminal-protected polypeptides (61-92%) including those containing unprotected OH, SH, and indole NH groups, with no detectable racemization. acylation -peptides-coupling- amino acids - medicinal chemistry