Combining the tail and the ring approaches for obtaining potent and isoform-selective carbonic anhydrase inhibitors: Solution and X-ray crystallographic studies
作者:Murat Bozdag、Marta Ferraroni、Elisa Nuti、Daniela Vullo、Armando Rossello、Fabrizio Carta、Andrea Scozzafava、Claudiu T. Supuran
DOI:10.1016/j.bmc.2013.11.016
日期:2014.1
However the pyridine derivative undergoes a tilt of the heterocyclic ring compared to the benzene analog, which leads to a very different orientation of the two scaffolds when bound to the enzyme. This tilt also leads to a clash between a carbon atom from the pyridine ring of the first inhibitor and the OH moiety of Thr200, leading to less effective inhibitory properties of the pyridine versus the benzene
5-(3-甲苯磺酰脲)吡啶-2-磺酰胺和4-甲苯磺酰苯磺酰胺(ts - SA)的区别仅在于CH被氮原子取代,但它们对金属酶碳酸酐酶的抑制特性却大不相同(CA,EC 4.2.1.1)。通过在两种化合物的人CA II加合物上进行X射线晶体学分析,这些差异已得到合理化。与所有磺酰胺一样,这两种化合物以去质子形式与酶活性位点的Zn(II)离子结合,并且它们的有机支架遍布整个腔,参与与氨基酸残基和水分子的许多相互作用。然而,与苯类似物相比,吡啶衍生物经历了杂环的倾斜,当与酶结合时,这导致两个支架的取向非常不同。该倾斜还导致来自第一抑制剂的吡啶环的碳原子与Thr200的OH部分之间的碰撞,从而导致吡啶相对于苯磺酰胺衍生物的有效抑制性质。的确,ts - SA是一种混杂的低纳摩尔抑制剂,占10种人(h)CA同种型中的7种,而吡啶磺酰胺仅是一种与肿瘤相关的hCA IX和XII的低纳摩尔抑制剂,对其他9种亚型