Human African trypanosomiasis is causing thousands of deaths every year in the rural areas of Africa. In this manuscript we describe the optimization of a family of phtalazinone derivatives. Phosphodiesterases have emerged as attractive molecular targets for a novel treatment for a variety of neglected parasitic diseases. Compound 1 resulted in being a potent TbrPDEB1 inhibitor with interesting activity against T. brucei in a phenotypic screen. Derivative 1 was studied in an acute in vivo mouse disease model but unfortunately showed no efficacy due to low metabolic stability. We report structural modifications to achieve compounds with an improved metabolic stability while maintaining high potency against TbrPDEB1 and T. brucei. Compound 14 presented a good microsomal stability in mouse and human microsomes and provides a good starting point for future efforts.

中文翻译：

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领先的酞菁酮磷酸二酯酶抑制剂作为新型抗锥虫化合物的优化。

非洲人类锥虫病每年在非洲农村地区造成数千人死亡。在此手稿中，我们描述了酞菁酮衍生物家族的优化。磷酸二酯酶已成为一种有吸引力的分子靶标，可用于治疗多种被忽视的寄生虫病。化合物1导致作为一种有效的抑制剂TbrPDEB1用针对令人感兴趣的活性布氏锥虫在表型筛选。在急性体内小鼠疾病模型中对衍生物1进行了研究，但不幸的是，由于代谢稳定性低，它没有显示出任何功效。我们报道了结构修饰，以实现具有改善的代谢稳定性的化合物，同时保持针对TbrPDEB1和布氏锥虫。化合物14在小鼠和人微粒体中表现出良好的微粒体稳定性，并为以后的工作提供了良好的起点。