A NOVEL QSAR MODEL FOR EVALUATING AND PREDICTING THE INHIBITION ACTIVITY OF H1-RECEPTOR ANTAGONISTS: A SERIES OF THIENOPYRIMIDINE DERIVATIVES

ABSTRACT A Quantitative Structure Activity Relationship (QSAR) study has been established using combination of most influencing physiochemical parameters viz. thermodynamic, electronic, geometric & quantum mechanical descriptors, and H1-antihistaminic activity of a series of thienopyrimidines, the novel Histamine H1 receptor antagonists. Genetic function approximation (GFA) technique was used to identify the descriptors that have influence on biological activity. Dipole, AlogP 98, Jurs and LUMO descriptors were found to influence biological activity significantly. Lipophilicity of compounds was found to have a significant role in H1 Histaminic inhibition along with other thermodynamic, spatial and electronic descriptors. Positive contribution of Dipole, AlogP 98 descriptors suggests that molecules with lipophilic-electronic substituents are more likely to improve the potency. Developed models were found to be significant and predictive as evidenced from their internal and external cross-validation statistics.  Keywords: H1-receptor antagonists; thienopyrimidines; molecular descriptor; genetic function approximations; cross-validation; quantitative structure activity relationship Abbreviations: QSAR : Quantitative structure activity relationship GFA   : Genetic function approximation LOF   : Friedman’s lack of fit VIF    : Variance inflation factor Â