A QM/MM molecular dynamic simulation and vibrational spectroscopic study of 6-azaCytidine and cytidine

Abstract: The conformational and vibrational properties of 6-azaCytidine (6-azaC) and Cytidine (Cyt) have been studied in gas phase and aqueous environment. The two most stable conformers of each molecule have been identified and investigated in more details. The stability order of the two most stable conformers of both molecules is changing going from gas phase to solution. The first solvation shell of both molecules has been studied using QM/MM-MD (Quantum Mechanics/Molecular Mechanics-Molecular Dynamic) simulations. The Raman vibrational spectra in gas phase and aqueous solution have been simulated and compared with the available experimental data. The two molecules exhibit certain differences reflected in their spectra as a result of structural and conformational differences.