ANTIINFLAMMATORY ACTIVITY OF NOVEL INDOLE-DERIVATIVES

3-[(2-Imidazolyl, benzimidazolyl or benzoxazolyl)alkyl]indoles 2a-h were synthesized by cyclizing the carboxylic group of (3-indolyl)alkanoic acids 1 with ethylenediamine, o-phenylenediamine or o-aminophenol, respectively. Reaction of 1 with p-aminoacetophenone or aryl-substituted thiosemicarbazones yielded N-(4-acetylphenyl)-(2 or 4)-(indol-3-yl)alkylcarboxamides 3a-b or l-arylidene 4-[2-(indol-3-yl)(acetyl or propionyl)]thiosemicarbazides 5a-h; 3a-b were cyclized into N-[4-(2-aminothiazol-4-yl)phenyl]-(2 or 4)-(indol-3-yl)alkylcarboxamides 4a-b. Cyclization of 5a-h with malonic acid yielded 1-[2-(indol-3-yl)(acetyl or propionyl)]-3-arylideneamino-2-thiobarbituric acids 6a-h, which were finally converted into corresponding Mannich bases 7a-f. Compounds 2a-h, 4a-b, 6a-h and 7a-f were evaluated for their antiinflammatory activity. Compounds 2e, 2g, 4b, 6c and 6d exhibited promising antiinflammatory activity with a lower ulcerogenic liability than indomethacin.