Enzymes in carbohydrate synthesis: N-acetylneuraminic acid aldolase catalyzed reactions and preparation of N-acetyl-2-deoxy-D-neuraminic acid derivatives

This paper describes the structural characteristics of substrates accepted by N-acetylneuraminic acid (Neu5Ac) aldolase (E.C. 4.1.3.3), the results from its stability studies, its use in the synthesis of Neu5Ac and 9-O-acetyl-Neu5Ac (Neu5,9Ac sub(2)), and the chemical conversion of Neu5Ac to the 2-deoxy derivatives. Values of kinetic parameters (K sub(m) and V sub(max)) for 14 aldoses including N-acetyl-D-mannosamine (ManNAc) and pyruvate were determined at pH 7.5 and 25 degree C in the direction of condensation. To illustrate the utility of Neu5Ac as a synthetic starting material, a potential inhibitor of Neu5Ac-associated enzymes was prepared. Its structure was analyzed by super(1)H and super(13)C NMR spectroscopy and X-ray crystallography.