%0 Journal Article
%T Density Functional Theory (B3LYP/6-311+G(d, p)) Study of Stability, Tautomerism and Acidity of 2-Thioxanthine in Gas and Aqueous Phases
%J -
%D 2019
%X 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(1,3,7), 2TXX(1,3,9), 2TX(1,7,10) and 2TX(1,9,10). The relative stability decreases in the order 2TX(1,3,7)> 2TX(1,3,9)> 2TX(1,9,10)> 2TX(1,7,10). This work establishes that the tautomer 2TX(1,9,10) comes from the 2TX(1,3,7) via the 2TX(1,3,9) one. It demonstrates that the acidity of the most stable tautomer¡¯s nitrogen 2TX(1,3,7), decreases in the order 7> 3> 1 in gas phase and in the order 3> 7>1 in aqueous phase. It provides data to elucidate the mechanisms to understand biological activities of 2£¿thioxanthine
%K 2-Thioxanthine
%K Stability
%K Tautomerism
%K Acidity
%K B3LYP
%U http://www.sciencepublishinggroup.com/journal/paperinfo?journalid=228&doi=10.11648/j.ijctc.20190701.17