設計與合成吲哚-2-酮衍生物作為潛能蛋白激酶抑制劑及其活性評估

Abstract

為同時抑制多個疾病相關之標靶，先期研究將抗有絲分裂劑之藥效基團（磺醯胺基）和吲哚-2-酮結合。第一系列共軛吲哚-2-酮類蛋白質抑制劑以J3944為代表。以此為基礎設計第二系列化合物，將位於吲哚-2-酮骨架第三位置的苯環由吡咯環取代，這致使化合物對細胞週期蛋白依賴型激酶2具有更強的抑制活性，其半抑制濃度為0.4微莫爾。若在吲哚-2-酮之第五或七位置進行修飾則會導致化合物的活性變差。相反的，6-芳基脲-3-吡咯-2-亞甲基吲哚-2-酮類衍生物對多個受體酪氨酸激酶具有納莫爾級的抑制活性。構效關係的研究結果顯示，化合物具有蛋白質激酶抑制活性的關鍵在於：鏈結取代基位於吲哚-2-酮骨架中心之位置，以及脲基中的羰基官能基。因此，設計第三系列基於吲哚-2-酮的抑制劑時，在吲哚-2-酮的六號位置引入了丙二醯胺鏈結。而丙二醯胺的構象限制又致使第四系列具有吡啶-2-酮基和吡啶-4-酮基的抑製劑隨之被研發出來。生物活性研究顯示，第三系列丙二醯胺類化合物和第四系列吡啶酮類化合物是有潛效的極光激酶B抑制劑，其半抑制濃度在亞微莫爾至納莫爾範圍。這些化合物對Fms樣的酪胺酸激酶3也有交叉抑制作用。我們認為相繼抑制Fms樣酪胺酸激酶3和極光激酶B可能會對治療急性髓系白血病提供潛在的幫助。本論文以吲哚-2-酮之適用性為出發點，進行有潛效蛋白質激酶抑制劑的研發，並從而得到具抑制極光激酶和其他蛋白激酶的化合物。

In order to hit several disease-relevant targets simultaneously, sulfonamido moiety, which is a pharmacophore of antimitotic agents, was conjugated to indolin-2-one. This resulted in the first series of indolin-2-one based inhibitors, such as J3944. Replacing phenyl ring on the 3-position of indolin-2-one by pyrrolyl ring led to more potent CDK2 inhibitor (IC50 = 0.4 μM). Modifications on linkages at the 5- or 7-position of indolin-2-one core resulted in much inferior compounds. In contrary, 6-arylureido-3-pyrrol-2-ylmethylideneindolin-2-one derivatives exhibited potency to multiple receptor tyrosine kinases in nanomolar range. Results of structure-activity relationship study showed that both position of linker on indolin-2-one core and carbonyl group in ureido moiety are crucial for kinase inhibition activity. The third series indolin-2-one based inhibitors were designed with malonamido moiety attached to the 6-position of indolin-2-one as the linker. Conformational restriction of malonamido moiety led to the fourth series inhibitors bearing pyridin-2-one and pyridin-4-one moieties. Biological studies showed that malonamide and pyridone compounds were potential Aurora-B kinase inhibitors with IC50 values in submicro- to nanomolar range. They also had cross activity to Flt-3. It is believed that the sequential inhibition of Flt-3 and Aurora-B kinase may provide potential therapeutic benefits to treat acute myeloid leukemia. In this thesis, the applicability of indolin-2-one as a reasonable starting point to develop potential protein kinase inhibitors was highlighted.