In order to search for new compounds with stronger anti-inflammatory activity and less side effects, phenyl 5-chloro-2-oxindole-1-carboxylate, obtained from 5-chloro-2-oxindole via esterification with phenyl chloroformate and subsequent hydrolyzation, reacted with 4-(methylsulfonyl) benzoyl chloride and 4-dimethylaminopyridine, followed by acidification with hydrochloric acid to yield phenyl 5-chloro- 3-(hydroxy-p-methylsulfonylphenylmethylene)-2-oxo-2,3-dihydroindole-1-carboxylate (II₁), which was condensed with corresponding amines, followed by acidification with hydrochloride acid to afford the target compounds II₂～II₁₅, respectively. Fifteen novel title compounds were synthesized, and their structures were confirmed by IR, ¹H NMR, MS spectra and elemental analyses. II₁₀, II₁₁ and II₁₅ exhibited marked anti-inflammatory activity in xylene-induced mice ear swelling model. Moreover, II₁₀ and II₁₁ showed significant anti-inflammatory activity comparable to diclofenac sodium and tenidap sodium (P＞0.05) in carrageenan-induced rat paw edema model. II₁₁ had less gastrointestinal side effect than diclofenac sodium (p＜0.05) and tenidap sodium (P＜0.01).

Key words: 5-chloro-3-(hydroxy-p-methylsulfonylphenylmethylene)-2-oxo-2,3-dihydroindole-1- carboxamides, gastrointestinal side effect, synthesis, anti-inflammatory activity, tenidap