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Identification of the Most Stable Guanine Tautomer for Hydroxylation Reaction Mechanism Studies using DFT calculations

Mamaru Bitew Alem


Abstract: Identifying the most stable tatutomer for reaction mechanism studies is essential. For this reason, the present work was intended to explore the most stable and reactive guanine tautomer. To explore the most stable guanine tautomer a DFT/B3LYP method and level of theory were applied for electronic structure calculation and quantum mechanical description. Guanine was shown to exist in four different tautomeric forms (2AX 19 H, 2AX 17 H, 2AX 3 7 H and 2AX 9 11 H), with the normalized energies 0 kcal/mol, 0.292 kcal/mol, 1.288 kcal/mol and 7.362 kcal/mol respectively. The electronic calculations found to support 2AX 17 H tautomer as the most stable and reactive guanine tautomer. We have also found that the keto forms are dominated over the enol tautomeric forms.

KEY WORDS: Enol , Guanine, ketol , tautomer.

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