Synthesis of enantiomerically pure quaternary glutamic acids via chemo- and diastereoselective alkylation of (5S)-3-([2-methoxycarbonyl]ethyl)-5-phenyl-5,6-dihydro-2H-1,4-oxazin-2-one

Synthesis of enantiomerically pure quaternary glutamic acids via chemo- and diastereoselective alkylation of (5S)-3-([2-methoxycarbonyl]ethyl)-5-phenyl-5,6-dihydro-2H-1,4-oxazin-2-one