Some new benzoxazolinone derivatives with analgesic and anti-inflammatory activities.

Fourteen new 6-acyl-2-benzoxazolinone, ethyl-(6-acyl-2-benzoxazolinone) acetate and (6-acyl-2-benzoxazolinone-3-yl) acetic acid derivatives were synthesized, and their physical properties and UV absorption data were determined. Their chemical structures were elucidated by IR, 1H-NMR and elemental analysis. The analgesic activities of these compounds were investigated by a modified Koster's test. It was shown that the respective activities of compounds 1-4 and 10-14 were higher than that of acetylsalicylic acid. Therefore, they were screened for additionally anti-inflammatory activities using the carrageenan mouse paw edema test. The compounds were further screened for their ability to inhibit prostaglandin E2 (PGE2) induced paw edema and compared to indometacin. Compounds 12 and 13 were very potent in inhibiting PGE2 induced edema.