X=Y-ZH SYSTEMS AS POTENTIAL 1,3-DIPOLES. PART 22. CYCLOADDITION REACTIONS OF PYRIDOXAL IMINES. RELEVANCE TO α-AMINO ACID RACEMASES AND TRANSAMINASES.

Article abstract of DOI:10.1016/S0040-4020(01)86100-7

Pyridoxal imines of α-amino acid esters and related amines undergo cycloaddition to N-phenylmaleimide on heating in acetonitrile, toluene or xylene.The cycloadditions proceed in good yield, are stereospecific, and involve an endo-transition state.The reac