ESSENTIAL DIFFERENCES IN SPONTANEOUS REACTION OF L-LYSINE AND L-ARGININE WITH FORMALDEHYDE AND ITS QUANTUM CHEMICAL INTERPRETATION

Abstract

It has been recently reported by us that spontaneous reaction between formaldehyde and L-lysine yields N-methylated products at room temperature. In this paper we discussed this reaction extending to L-arginine. While the reaction between formaldehyde and L-lysine produces different N-methylated derivatives, no methylated only NG-hydroxymethylated derivatives can be observed in the reaction mixture between formaldehyde and L-arginine. The difference in the reaction between L-lysine and L-arginine with formaldehyde can be explained with the different nucleophilicity of the amino group in lysine and that of the imino group in arginine examined by the electrostatic potential of N atoms by the ELPO quantumchemical calculation method of Náray-Szabó.