Aminocarbonyl Arylvinylbenzamides as Gastric Sparing Anti-inflammatory Agents

Some (E/Z)‐aminocarbonyl arylvinylbenzamides (B1–B15) were synthesized, evaluated for anti‐inflammatory activity and ulcerogenic tendency, and their effect on gastro‐intestinal motility in the rats was studied. These benzamides comprising of aliphatic unsaturated region situated between two amide linkages were synthesized by nucleophilic ring opening of appropriate azlactones (AZ1–AZ4) by suitable amines. The characterization of newly synthesized benzamides was performed by IR, 1H‐ and 13C‐NMR, mass and elemental analysis. Amongst the tested compounds, benzamide B1, B2, B4, B5, and B13 were able to produce comparable or superior anti‐inflammatory activity at 10 and 20 mg/kg p.o. dose with respect to standard diclofenac in carrageenan induced rat paw edema model with lessened propensity to cause gastro‐intestinal hypermotility and were found to have nil tendencies to generate gastric ulcers. A series of N‐[(E/Z)‐2‐(4‐substituted/unsubstitutedphenyl)‐1‐{[arylamino]carbonyl} vinyl]benzamides (B1–B15) was synthesized by utilizing easily accessible starting material 4‐substituted/unsubstituted benzylidene‐2‐phenyloxazol‐5‐one (AZ1–AZ4) and subjected to anti‐inflammatory activity, gastrointestinal motility, and gastric damage studies in rats.