Theoretical and QSPR Study of the Physicochemical Properties of Barbiturates by Using Chemical Graph Theory

In this study the relationship between the Randic (1X), Balaban (J), Szeged (Sz), Harary (H), Wiener (W), Hyper- Wiener (WW) and Wiener Polarity (Wp) to the thermal energy (Eth J/mol) and heat capacity (CV J/molK) of barbiturates is represented. The ab initio method with HF/6-31G level of theory was used for investigating the physicochemical properties of barbiturates.The multiple linear regressions (MLR) and Back ward methods (with significant at the 0.05 level) were employed to give the QSPR models.After MLR analysis, we studied the validation of linearity between the molecular descriptors in the best models for used properties. The predictive powers of the models were discussed by using the method of cross-validation. The results have shown that the Harary index could be efficiently used for estimating heat capacity (Cv) and two descriptors (Wp, WW) could be used for modeling and predicting the thermal energy of respect compounds.