Enantioselective synthesis of new 4-substituted glutamic acid derivatives

Several new 4-substituted glutamic acid derivatives are described: 4-phosphinomethyl glutamic acid derivatives were prepared starting from (2S)-N-Boc-tert-butyl-4-methylene glutamate. The 4-carboxymethyl and 4-aminomethyl glutamic acid derivatives were obtained using asymmetric 1,4-addition conjugate of the enolate of Schiff base 1 to unsaturated esters.