3D-QSAR CoMFA/CoMSIA studies on 5-aryl-2,2-dialkyl-4-phenyl-3(2H)-furanone derivatives, as selective COX-2 inhibitors.

Comparative Molecular Field Analysis (CoMFA) and Comparative Molecular Similarity Indices Analysis (CoMSIA) were performed on a series of 5-aryl-2,2-dialkyl-4-phenyl-3(2H)-furanone derivatives, as selective cyclooxygenase-2 (COX-2) inhibitors. Ligand molecular superimposition on the template structure was performed by the atom/shape based root mean square fit and database alignment methods. Removal of three outliers from the initial training set of 49 molecules improved the predictivity of the model. The statistically significant model was established of 36 molecules, which were validated by a test set of ten compounds. The atom and shape based root mean square alignment (IV) yielded the best predictive CoMFA model [R2(cv) = 0.664, R2 (non-cross-validated square of correlation coefficient) = 0.916, F value = 47.341, R2(bs) = 0.947 with six components, standard error of prediction36 = 0.360 and standard error of estimate36 = 0.180] while the CoMSIA model yielded [R2(cv) = 0.777, R2 (non-cross-validated square of correlation coefficient) = 0.905, F value = 66.322, R2(bs) = 0.933 with four components, standard error of prediction36 = 0.282 and standard error of estimate36 = 0.185]. The contour maps obtained from 3D-QSAR studies were appraised for activity trends for the molecules analyzed. Results indicate that steric, electrostatic, hydrophobic (lipophilic) and hydrogen bond donor substituents play a significant role in COX-2 inhibitory activity and selectivity of the compounds. The data generated from the present study will further help design novel, potent and selective COX-2 inhibitors.