Synthesis and Biological Evaluation of Salicylic Acid and N-Acetyl-2-carboxybenzenesulfonamide Regioisomers Possessing a N-Difluoromethyl-1,2-dihydropyrid-2-one Pharmacophore: Dual Inhibitors of Cyclooxygenases and 5-Lipoxygenase with Antiinflammatory Activity.