A highly efficient route to enantiomerically pure L-N-Bz-Pmp(t-Bu)2-OH and incorporation into a peptide-based protein tyrosine phosphatase inhibitor

Phosphonomethyl phenylalanine (Pmp), a nonhydrolyzable mimic of phosphotyrosine, is an important building block in the development of peptide-based PTP inhibitors. We have designed a novel, efficient synthesis of N-Bz-Pmp(t-Bu)(2)-OH. A Pmp-containing peptide based on a known biological substrate of the tyrosine phosphatase CD45 (Ac-TEGQ-Pmp-QPQP-NH2) inhibits CD45 with an IC50 value of approximately 100 mu M with virtually no inhibition of TCPTP up to concentrations of 120 mu M. (c) 2007 Elsevier Ltd. All rights reserved.