Structural and vibrational properties of a reverse inhibitor against the hiv virus Dideoxynucleoside zalcitabine in gas and aqueous solution phases

In the present chapter, the structural and vibrational properties of Zalcitabine, whose chemical name is Dideoxycytidine (DDC) were theoretically studied by using the hybrid B3LYP method together with the 6-31G(d) basis set. Two stable conformers for DDC were determined in both media. The structural properties of both conformers in aqueous solution were performed taking into account the solvent effects by means of the self- consistent reaction field (SCRF) method employing the integral equation formalism variant (IEFPCM). The magnitude of the intramolecular interactions of both sugar deoxyribose and pyrimidine rings of DDC in the two media were studied at the same level of theory by using natural bond orbital (NBO) calculations and the atoms and molecules theory (AIM). Thus, the atomic charges, molecular electrostatic potentials, bond orders, and the HOMO and LUMO orbitals for the two conformers of DDC were calculated and compared with those results obtained of the literature for other antiviral agent, thymidine. In addition, the force fields for those two stable structures were performed by using the SQM methodology, the internal normal coordinates and the.