2,4-Diamino-6,7-dimethoxyquinazolines. 3. 2-(4-heterocyclylpiperazin-1-yl) derivatives as .alpha.1-adrenoceptor antagonists and antihypertensive agents
作者:Simon F. Campbell、Rhona M. Plews
DOI:10.1021/jm00393a019
日期:1987.10
alpha-adrenoceptor affinity and antihypertensive activity. These quinazoline derivatives showed high binding affinity (ca. 10(-10) M) and selectivity (greater than 10,000) for alpha 1-adrenoceptors in vitro, with no relevant activity at alpha 2 sites. Several compounds displayed similar activity to prazosin (Ki = 1.9 X 10(-10) M) while the dimethoxytriazine derivative 30 (Ki = 8 X 10(-11) M) was more potent. Like
制备了一系列的4-氨基-6,7-二甲氧基-2(4-杂环基哌嗪-1-基)喹唑啉(3),并筛选了α-肾上腺素受体亲和力和降压活性。这些喹唑啉衍生物在体外对α1-肾上腺素受体具有高结合亲和力(约10(-10)M)和选择性(大于10,000),在α2位点无相关活性。几种化合物显示出与哌唑嗪(Ki = 1.9 X 10(-10)M)相似的活性,而二甲氧基三嗪衍生物30(Ki = 8 X 10(-11)M)更有效。像prazosin(pA2 = 8.37 +/- 0.24)一样,30被证明是有效的(pA2 = 8.63 +/- 0.15),去甲肾上腺素的α1介导的血管收缩作用的竞争性拮抗剂。系列3的高结合亲和力最可能是由于在生理pH下形成了质子化的α1-肾上腺素受体药效基团33,加上喹唑啉2取代基的有效疏水相互作用。哌唑嗪和30的计算机辅助叠加表明,糠酰和二甲氧基三嗪部分之间几乎没有结构对应,而且