title: 2-aryl-5-benzoxazolealkanoic acid derivatives with notable antiinflammatory activity.
abstract: The synthesis and antiinflammatory activity of 5-substituted 2-arylbenzoxazoles are described. Initial screening on carrageenin-induced rat paw edema showed that alpha-methylacetic substitution in the 5 position was preferable to substitutions with the equivalent esters, amides, alcohols, amines or tetrazoles. Halogen substitution in the aryl ring led to the most active compounds which were 2-(4-chlorophenyl)-alpha-methyl-5-benzoxazoleacetic acid (14) and 2-(4-fluorophenyl)-alpha-methyl-5-benzoxazoleacetic acid (29). These compounds were three to five times more active than phenylbutazone as assessed from ED30 values determined on rat paw edema 5 hr after single oral doses.
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000138:chemical synthesis* / Q000627:therapeutic use / Q000633:toxicity; D002264:Carboxylic Acids / Q000138:chemical synthesis / Q000627:therapeutic use / Q000633:toxicity; D002351:Carrageenan; D004487:Edema / Q000139:chemically induced / Q000188:drug therapy; D005260:Female; D007928:Lethal Dose 50; D010080:Oxazoles / Q000138:chemical synthesis* / Q000627:therapeutic use / Q000633:toxicity; D010991:Plethysmography; D051381:Rats
chemical_list: D000893:Anti-Inflammatory Agents; D002264:Carboxylic Acids; D010080:Oxazoles; D002351:Carrageenan