Ethenesulfonamide Derivatives, a Novel Class of Orally Active Endothelin-A Receptor Antagonists
作者:Hironori HARADA、Jun-ichi KAZAMI、Susumu WATANUKI、Ryuji TSUZUKI、Katsumi SUDOH、Akira FUJIMORI、Akihiro TANAKA、Shin-ichi TSUKAMOTO、Isao YANAGISAWA
DOI:10.1248/cpb.49.606
日期:——
In the present article we wish to report the discovery of a novel class of ETA-selective endothelin (ET) receptor antagonists through the modification of the ETA/ETB non-selective antagonist, Ro47-0203 (Bosentan, 1). Replacement of the benzenesulfonamide group of 1 with a 2-phenylethenesulfonamide group gave compound 5a and resulted in improvement in ETA-selectivity. Optimization of the alkoxy side chain attached to the core pyrimidine ring yielded the 2-fluoroethoxy derivative (5n) with further improvement of ETA-selectivity. [IC50=2.1 nM for ETA receptor, ETB/ETA ratio=1200]. After oral administration, compound 5n inhibited the big ET-1 induced pressor response in pithed rats with a DR2 value of 2.6 mg/kg and also exhibited a potent antagonistic activity in conscious rats.
在本文章中,我们希望报告通过改造ETA/ETB非选择性拮抗剂Ro47-0203(博生坦,1)发现一种新型ETA选择性内源性血管收缩素(ET)受体拮抗剂。将1的苯磺酰胺基团替换为2-苯基乙烯磺酰胺基团,得到化合物5a,并改善了ETA选择性。对连接在核心嘧啶环上的烷氧基侧链进行优化,得到2-氟乙氧基衍生物(5n),进一步提高了ETA选择性。[IC50 = 2.1 nM,ETB/ETA比率=1200]。口服给药后,化合物5n抑制了大剂量ET-1在麻醉大鼠中的压升反应,DR2值为2.6 mg/kg,并且在清醒的大鼠中表现出强效的拮抗活性。