Orthogonally protected Abu(P) (benzyl (2R,S)-4-diethylphosphonyl-2-phthalim
ido butanoate 4) has been synthesized. It has been used as a key intermedia
te for the synthesis of two new phthalimido-desmuramyldipeptide analogs con
taining diethylphosphnate moiety at the position of omega-carboxylic group
of Glu.