[Study by the proton magnetic resonance method of complex formation between nucleosides and compounds modeling amino acid residues of proteins in dimethyl sulfoxide]

Abstract

Proton magnetic resonance was used to investigate in dimethyl-sulfoxide specificity of complex formation between nucleosides and a number of substances modelling of carboxyl, guanidine and amide side chain residues of aminoacids. It was observed downfield chemical shift of NH2 group of guanosine and disappearence. NH groups resonance for all nucleosides containing its in heterocycle in complex with carboxyl group. The next selectivity of interaction of nucleosides with carboxyl was observed: Ino greater than Guo greater than Urd ==Thd greater than Ado==Cyd. Obtained data indicates formation specific hydrogen bonds between carboxyl group and NH2 group of guanine and more strong hydrogen bonds with NH groups of all bases. In the case of guanidine group there are more weaker interaction and for amide group complex is not observed at all.