Imidazo(1,2-a)pyridines. I. Synthesis and Inotropic Activity of New 5-Imidazo(1,2-a)pyridinyl-2(1H)-pyridinone Derivatives.
作者:Motosuke YAMANAKA、Kazutoshi MIYAKE、Shinji SUDA、Hideto OHHARA、Toshiaki OGAWA
DOI:10.1248/cpb.39.1556
日期:——
A series of 1, 2-dihydro-5-imidazo[1, 2-α]pyridinyl-2(1H)-pyridonones was synthesized and evaluated for positive inotropic activity. 1, 2-Dihydro-5-imidazo[1, 2-α]pyridin-6-yl-6-methyl-2-oxo-3-pyridinecarbonitrile (11a) hydrochloride monohydrate (E-1020) was found to be a potent and selective inhibitor of phosphodiesterase III and a long-acting, potent, orally active positive inotropic agent. Additional imidazo[1, 2-α]pyridin-2-yl (3a), -3-yl (16), -7-yl (20) and -8-yl (24a) compounds were also prepared. Altering the pyridine substitution from the 2-position to the 6-position produced a 2-fold increse in the i.v. cardiotonic potency (ED50) from 52 to 23 μg/kg, while substitution at the 3-, 7- or 8-position reduced potency. In the 2-positional isomers, introduction of halogen groups enhanced the activity and 3-chloro-1, 2-dihydro-5-(6-fluoroimidazo[1, 2-α]pyridin-2-yl)-6-methyl-2(1H)-pyridinone (3u) was the most potent (i.v. ED50 11 μg/kg) in this series. E-1020 is presently under development for the treatment of congestive heart failure.
合成了一系列1,2-二氢-5-咪唑[1,2-α]吡啶基-2(1H)-吡啶酮,并评估了它们的正性变力活性。1,2-二氢-5-咪唑[1,2-α]吡啶-6-基-6-甲基-2-氧-3-吡啶腈(11a)盐酸盐一水合物(E-1020)被发现是一种强效且选择性的磷酸二酯酶III抑制剂,以及一种长效、强效、口服活性正性变力剂。还制备了额外的咪唑[1,2-α]吡啶-2-基(3a)、-3-基(16)、-7-基(20)和-8-基(24a)化合物。将吡啶取代从2位改变到6位,静脉注射强心效力(ED50)从52增加到23 μg/kg,增加了2倍,而在3-、7-或8位取代则降低了效力。在2位异构体中,引入卤素基团增强了活性,3-氯-1,2-二氢-5-(6-氟咪唑[1,2-α]吡啶-2-基)-6-甲基-2(1H)吡啶酮(3u)是该系列中最强效的(静脉ED50 11 μg/kg)。E-1020目前正在开发用于治疗充血性心力衰竭。