Density Functional Theory (B3LYP/6-311+G(d, p)) Study of Stability, Tautomerism and Acidity of 2-Thioxanthine in Gas and Aqueous Phases

Abstract

This work is a contribution of theoretical chemistry to the knowledge of 2-thioxanthine's properties. Its aim first consists in checking the chemistry's results related to the exploitation of semi-empirical methods; it provides theoretical data on the acidity of 2-thioxanthine tautomers. To do this, the DFT method with the B3LYP functional, associated with the 6-311+G(d, p) basis set was used. The aqueous phase was modelled with the Polarizable Continuum Model (PCM). The results show that in gas and aqueous phases 2-thioxanthine can exist as a mixture of four tautomers 2TX(