A number of polychlorinated (phenoxyphenyl)acetic acids were prepared as close structural analogues of the antiinflammatory compound fenclofenac, [2-(2,4-dichlorophenoxy)phenyl]acetic acid. Increased potency was shown in several of these compounds, in particular, [2-(2,3,5,6-tetrachlorophenoxy) phenyl]acetic acid (8), which was 40 times more potent than fenclofenac in the adjuvant-induced arthritis screen. In further tests it was found to be equipotent with indomethacin but with a much reduced incidence of acute toxicity (LD50 and ulcerogenicity). On chronic dosing, however, serious toxicity problems arose (including anemia, neutrophilia, and severe peritonitis), and this led to the abandonment of further work on the compound. Three further analogues were prepared containing NH, S, and SO moieties bridging the phenyl rings. Although the NH compound bore a very close structural resemblance both to the above O-linked compound and the potent antiinflammatory drug diclofenac, [2-[(2,6-dichlorophenyl)imino]phenyl]acetic acid, it showed low activity in primary screens. Similarly, neither the S- or SO-bridged analogues had potencies that approached that of 8.

中文翻译：

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具有抗炎活性的取代的（2-苯氧基苯基）乙酸。2。

制备了许多多氯代（苯氧苯基）乙酸作为抗炎化合物芬氯芬酸[2-（2，4-二氯苯氧）苯基]乙酸的紧密结构类似物。这些化合物中的几种化合物，特别是[2-（2,3,5,6-四氯苯氧基）苯基]乙酸（8），显示出更高的效价，在佐剂诱导的关节炎筛查中，其效价比芬氯芬酸高40倍。 。在进一步的测试中，发现与消炎痛是等效的，但急性毒性（LD50和致溃疡性）的发生率大大降低。然而，在长期给药时，出现严重的毒性问题（包括贫血，中性粒细胞增多和严重的腹膜炎），这导致对该化合物的进一步研究工作被放弃。制备了另外三个类似物，它们含有桥接苯环的NH，S和SO部分。尽管NH化合物与上述O-连接的化合物和强效抗炎药双氯芬酸[2-[（（2,6-二氯苯基）亚氨基]苯基]乙酸都具有非常相似的结构相似性，但在初筛中显示出较低的活性。同样，S桥或SO桥的类似物均未达到8的效价。