Biopolymers and cell. 1993. Volume 9. № 3. 17 - 22

ZHELTOVSKY N. V., SAMIYLENKO S. P., KOLOMIETS I. N., KONDRATYUK I. V., STEPANYUGIN A. V.

The Investigation of Interactions of Hypoxanthine, Xanthine and Their Methyl and Glycosyl Derivatives With Amino Acid Carboxylic Group by Spectroscopic Methods

Summary

    The interactions of some methyl and glycosyl derivatives of hypo-xanthine and xanthine with ionized and neutral amino acid carboxylic group were in¬vestigated in dimethylsulfoxide. It was established that ionized carboxylic group forms complexes with hypoxanthine, inosine, xanthine, 3-methylxanthine and 9-methylxanthine. In the last case the proton transfer occurs from the base to carboxylate-ion. The met-hylation of hypoxanthine and xanthine nucleosides at N7 atoms results in their ability to interact with a neutral carboxylic group. The weak interaction with neutral carbo¬xylic group was observed in the case of 9,-methylxanthine. 1-Methylxanthine proved to be indifferent to the two forms of carboxylic group.