Studies towards a total synthesis of Sarains A-C. Stereospecific condensation of α,β-unsaturated esters with the phenyl oxazoline derivative of threonine

Article abstract of DOI:10.1016/S0040-4039(98)02639-2

Michael addition of oxazoline lithium enolate 5 to E and Z α,β- unsaturated esters proceeds with high enoate facial selectivity to yield enantiopure oxazoline derivatives of disubstituted glutamic acids. When a Z enoate is employed, the C4'-C3'-C7' stereo