3D QSAR STUDIES IN CONJUNCTION WITH k-NEAREST NEIGHBOR MOLECULAR FIELD ANALYSIS (k-NN-MFA) ON A SERIES OF SUBSTITUTED 2-PHENYL-BENZIMIDAZOLE DERIVATIVES AS AN ANTI ALLERGIC AGENTS

A set of forty one substituted 2-phenyl-benzimidazole with anti allergic activity against IgE was subjected to three dimensional quantitative structure activity relationship studies through recently introduced knearest neighbor molecular field analysis with step wise forward-backward as variable selection method to study the correlation between the molecular properties and the In-vitro IgE activities. In the present study k-NN-MFA calculations for both electrostatic and steric field were carried out. The master grid maps derived from the best model has been used to display the contribution of electrostatic potential and steric field. The k-NN-MFA models obtained by using 90 % of training set selection showed that electrostatic and steric interactions play major role in determining biological activity. The statistical results showed significant correlation coefficient r (q) of 0.5757, r for external test set (pred_r) 0.7238, coefficient of correlation of predicted data set (pred_rse) of 0.5799, degree of freedom 33 and k nearest neighbor of 2.The k-NN MFA contour plots provided further understanding of the relationship between the structural features of substituted-2-phenyl-benzimidazole derivatives and their activities, which should be applicable to design new, potential anti allergic agents.