Analgesic activity of acylated 2-benzoxazolinone derivatives

Ten new benzoxazolinone derivatives having a disubstituted benzoyl group at the six position of the ring were synthesized by reacting 2-benzoxazolinon e with aromatic carboxylic acids in the presence of polyphosphoric acid. Th e structure of the compounds were elucidated by IR,H-1 NMR, MS and elementa l analysis. Analgesic activity was evaluated by a modified Koster test. Sev en compounds showed analgesic activities higher than that of acetylsalicyli c acid. (C) 1999 Elsevier Science S.A. All rights reserved.