Prototropic molecular–zwitterionic tautomerism of xanthine and hypoxanthine

Autor:	S. P. Samijlenko, I. M. Kolomiets, I. V. Kondratyuk, Dmytro M. Hovorun
Rok vydání:	2000
Předmět:	Inorganic Chemistry chemistry.chemical_compound Chemistry Stereochemistry Organic Chemistry Proton NMR Anhydrous Xanthine Tautomer Spectroscopy Hypoxanthine Analytical Chemistry
Zdroj:	Journal of Molecular Structure. 523:109-118
ISSN:	0022-2860
Popis:	The prototropic molecular–zwitterionic tautomerism of xanthine (Xan) and hypoxanthine (Hyp) was investigated by the semi-empirical quantum-chemical AM1 method. Geometric, energetic and electronic features of their complete molecular–zwitterionic families of tautomers were established. The influence of the environment with universal solvatation mechanism on the tautomeric equilibrium was evaluated at Onzager approximation. The comparison of the calculations with the 1 H NMR data favors the N7H Xan and the N9H Hyp tautomers in anhydrous DMSO solutions. The possible biochemical role of tautomeric (especially zwitterionic) forms of Xan and Hyp is discussed. Stabilizing influences of environment and specific interactions with proteins on rare tautomeric forms are considered.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::00b1a4ba50f3c0dea0dfb39326cecc79 https://doi.org/10.1016/s0022-2860(99)00385-3 Zobrazit plný text záznamu Full Text from ScienceDirect