Evaluation of 1,1-cyclopropylidene as a thioether isostere in the 4-thio-thienopyrimidine (TTP) series of antimalarials
作者:Robert D. Barrows、Jared T. Hammill、Michael C. Tran、Mofolusho O. Falade、Amy L. Rice、Christopher W. Davis、Thomas J. Emge、Paul R. Rablen、R. Kiplin Guy、Spencer Knapp
DOI:10.1016/j.bmc.2020.115758
日期:2020.11
(TTP) series of antimalarials, represented by 1 and 17, potently inhibit proliferation of the 3D7 strain of P. falciparum (EC50 70–100 nM), but suffer from oxidative metabolism. The 1,1-cyclopropylidene isosteres 6 and 16 were designed to obviate this drawback. They were prepared by a short route that features a combined Peterson methylenation / cyclopropanation transformation of, e. g., ketone 7. Isosteres
以1和17表示的4-(杂芳硫基)噻吩并[2,3- d ]嘧啶(TTP)系列抗疟药有效抑制恶性疟原虫3D7菌株的增殖(EC 50 70–100 nM),但受到影响来自氧化代谢。设计1,1-环亚丙基等排物6和16以消除该缺点。它们是通过短途径制备的,所述短途径具有例如酮7的结合的彼得森甲基化/环丙烷化转化的特征。相对于父母1和17,等位基因6和16具有显着减弱的抗疟疾效力。可以根据后两个方面增加的平面外空间需求来合理化此结果。为了支持该假设,相对平坦的酮7保留了1的某些效力,即使就电子学,键合长度和角度而言,酮7的模拟性相对较差。我们还证明了晶体学和计算上质子化时分子内硫空穴相互作用1的强度明显增加。