AbstractFlupirtine and retigabine were essential drugs to combat pain and epilepsy. However, the Kv7 potassium channel openers are fraught with hepatotoxicity and tissue discoloration, respectively, limiting their therapeutic value. Both adverse events are likely due to reactive metabolites arising from oxidative metabolism. Designing safer analogues lacking the structural elements leading to described side effects is an active area of current research. One of the main metabolites of flupirtine is the biologically inactive 4‐fluorohippuric acid. Hitherto unexplained, the proposed metabolic pathway leading to the formation of 4‐fluorohippuric acid from flupirtine is verified here. Through the use of eighteen flupirtine analogues, mechanistic details of this pathway could be elucidated. A possible connection with the in vitro hepatotoxicity of the flupirtine analogues and the levels of 4‐fluorobenzoic acid formed in enzyme incubations was examined by correlation analysis. These findings provide important information for the design of new flupirtine analogues as potential drug candidates.
摘要氟吡汀和瑞替加滨是治疗疼痛和癫痫的基本药物。然而,Kv7 钾通道开放药分别存在肝毒性和组织变色问题,限制了它们的治疗价值。这两种不良反应很可能是由于氧化代谢产生的活性代谢物造成的。设计出缺乏导致上述副作用的结构元素的更安全的类似物是当前研究的一个活跃领域。氟吡汀的主要代谢物之一是无生物活性的 4-氟嬉尿酸。迄今为止,导致氟吡汀形成 4-氟环嘌呤酸的代谢途径尚未得到解释,本文验证了这一提议。通过使用 18 种氟吡汀类似物,可以阐明这一途径的机理细节。通过相关分析,研究了氟吡汀类似物的体外肝毒性与酶培养中形成的 4-氟苯甲酸水平之间可能存在的联系。这些发现为设计新的氟吡汀类似物作为潜在候选药物提供了重要信息。