The indolin-2-one fused-ring system and the 2,4-dimethylpyrrole unit represent key structural motifs in the anticancer drug sunitinib (Sutent®) and predecessor angiogenesis inhibitors that have undergone anticancer clinical trials (e.g. semaxanib, SU5416). In pursuit of novel anti-angiogenic scaffolds, we were interested in identifying whether the indolin-2-one group in these structures could be modified without losing activity. This paper describes novel condensation chemistry used to prepare a test series of (E)- and (Z)-alkenes related to SU5416 that retain the 2,4-dimethylpyrrole unit while incorporating ring-opened indolin-2-ones. Unique structural characteristics were identified in the compounds, such as intramolecular hydrogen bonds in the (Z)-alkenes, and several examples were shown to possess significant anti-angiogenic activity in a rat aorta in vitro model of angiogenesis. The work demonstrates that the indolin-2-one moiety is not an absolute requirement for angiogenesis inhibition in the sunitinib/SU5416 class.
吲哚啉-2-酮融合环系统和 2,4-二甲基吡咯单元是抗癌药物舒尼替尼(Sutent®)和已进行抗癌临床试验的前身血管生成抑制剂(如 semaxanib、SU5416)的关键结构基团。为了寻找新型抗血管生成支架,我们有兴趣确定这些结构中的吲哚啉-2-酮基是否可以在不失去活性的情况下进行修饰。本文介绍了用于制备与 SU5416 相关的(E)-和(Z)-烯试验系列的新型缩合化学,这些烯保留了 2,4-二甲基吡咯单元,同时加入了开环的吲哚啉-2-酮。在这些化合物中发现了独特的结构特征,如 (Z)- 烯烃中的分子内氢键,并在大鼠主动脉血管生成的体外模型中证明了几个实例具有显著的抗血管生成活性。研究结果表明,吲哚啉-2-酮分子并不是抑制舒尼替尼/SU5416 类药物血管生成的绝对必要条件。