Asymmetric synthesis of all four isomers of topographically constrained novel amino acids: β-isopropyltyrosines

Article abstract of DOI:10.1016/S0957-4166(97)00381-9

All four stereoisomers of the highly constrained novel amino acid, β-isopropyltyrosine, have been synthesized with high stereoselectivities (>90% de) and in 40-50% overall yields by using the optically pure 4-phenyloxazolidinone as a chiral auxiliary via asymmetric Michael addition, direct or indirect azidation, hydrogenolysis and demethylation reactions.