Phototautomerism of Isocytosine in a Water Medium: Theoretical and Experimental Study

Resumo

We have carried out a combined theoretical (at the TDDFT BLYP/6-311++G** level of theory) and experimental study of the mechanism of phototautmerization of the N(3)H oxo tautomer of isocytosine dissolved in a water medium. The study reveals that this photoreaction occurs along the ¹πσ* excited-state reaction paths of the oxo and hydroxy tautomers of the compound through conical intersections S₀/S₁. The last strucutres are located at the CASSCF level for both tautomers.