a quantitative structure-activity relationship (qsar) study of some diaryl urea derivatives of b-raf inhibitors

in the current study, both ligand-based molecular docking and receptor-based quantitative structure activity relationships (qsar) modeling were performed on 35 diaryl urea derivative inhibitors of v600e b-raf. in this qsar study, a linear (multiple linear regressions) and a nonlinear (partial least squares least squares support vector machine (pls-ls-svm)) were used and compared. the predictive quality of the qsar models was tested for an external set of 31 compounds, randomly chosen out of 35 compounds. the results revealed the more predictive ability of pls-ls-svm in analysis of compounds with urea structure. the selected descriptors indicated that size, degree of branching, aromaticity, and polarizability affected the inhibition activity of these inhibitors. furthermore, molecular docking was carried out to study the binding mode of the compounds. docking analysis indicated some essential h-bonding and orientations of the molecules in the active site. the solubility and dissolution rate of abz were increased 1.8-2.6 folds and 3-25 folds, respectively. unexpectedly, sls decreased the solubility index of drug powder even lower than the unprocessed drug which was attributed to drug-sls ionic interaction as depicted from fourier transform infrared spectroscopy. it was concluded that by applying the facile, one-step, industrially scalable technique and the use of small amounts of excipient (only 4% of the formulation), a great improvement (21 folds) in dissolution rate of abz was achieved. this finding may be used in the pharmaceutical industries for the formulation of therapeutically efficient dosage forms of class ii and iv drugs classified in biopharmaceutical classification system.