The optimization of a series of 5-phenylacetyl 1,4,5,6-tetrahydropyrrolo[3,4-c]pyrazole derivatives toward the inhibition of Aurora kinases led to the identification of compound 9d. This is a potent inhibitor of Aurora kinases that also shows low nanomolar potency against additional anticancer kinase targets. Based on its high antiproliferative activity on different cancer cell lines, favorable chemico-physical and pharmacokinetic properties, and high efficacy in in vivo tumor models, compound 9d was ultimately selected for further development.

中文翻译：

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1,4,5,6-四氢吡咯并[3,4-c]吡唑类化合物：鉴定出具有良好抗肿瘤激酶抑制作用的有效Aurora激酶抑制剂。

一系列针对抑制Aurora激酶的5-苯基乙酰基1,4,5,6-四氢吡咯并[3,4-c]吡唑衍生物的优化导致了化合物9d的鉴定。这是Aurora激酶的有效抑制剂，对其他抗癌激酶靶标也显示出较低的纳摩尔浓度。基于其对不同癌细胞系的高抗增殖活性，良好的化学物理和药代动力学特性以及在体内肿瘤模型中的高功效，最终选择了化合物9d进行进一步开发。