Various dimethyl 3-substituted pyrrole-2, 4-dicarboxylates (3) were synthesized by the reaction of methyl isocyanoacetate (2) with methyl α-isocyanoacrylates (5) in the presence of base. This type of reaction was also applicable to the preparation of 3-substituted pyrrole-2, 4-dicarboxamides (10) by employing appropriate amide compounds (8) or (9) and (12) as reactants. Hydrolysis followed by decarboxylation of the pyrrole diester compounds (3) gave 3-substituted pyrroles (14) in good yields. A series of these compounds (14) showed antiinflammatory activities against carrageenan-induced rat paw edema. Among the compounds tested, 3-(2-chlorophenyl) pyrrole (14d) was found to be more potent than mefenamic acid.
通过
异氰基乙酸甲酯(2)与α-异
氰基
丙烯酸甲酯(5)在碱存在下的反应,合成了各种 3-取代的
吡咯-2,4-二
羧酸二甲酯(3)。这种反应也适用于以适当的酰胺化合物(8)或(9)和(12)为反应物,制备 3-取代的
吡咯-2,4-二甲酰胺(10)。
吡咯二酯化合物(3)
水解后再进行脱羧反应,可以得到产率很高的 3-取代
吡咯(14)。一系列这些化合物(14)对角叉菜胶诱导的大鼠爪
水肿具有抗炎活性。在测试的化合物中,发现 3-(2-
氯苯基)
吡咯(14d)比
甲芬那酸更有效。