Synthesis and evaluation of phosphoramidate amino acid-based inhibitors of sialyltransferases.

Several phosphoramidate analogues of CMP-N-acetylneuraminic acid were prepared for evaluation as inhibitors of alpha-2,3- and alpha-2,6-sialyltransferase. Central to the synthesis was the oxidative coupling of an amino acid ester with an H-phosphonate to construct the phosphoramidate linkage. All compounds synthesized were weak inhibitors of both of the sialyltransferases as determined by an HPLC-based inhibition assay.