作者:Ichiro Araya、Shintaro Kanazawa、Hiroyuki Akita
DOI:10.1248/cpb.56.176
日期:——
A scaleable synthetic route is described to obtain 2-(4-acetylpiperadin-1-yl)-6-[3,5-bis(trifluoromethyl)phenylmethyl]-4-(2-methylphenyl)-6,7,8,9-tetrahydro-5H-pyrimido[4,5-b][1,5]oxazocin-5-one (1, KRP-103) as a neurokinin (NK)1 antagonist. The key step in the synthesis is the intramolecular cyclization of N-[3,5-bis(trifluoromethyl)phenylmethyl]-N-(3-hydroxypropyl)-4-chloro-6-(2-methylphenyl)-2-methylthiopyrimidine-5-carboxamide (15) which was obtained by amide formation between 4-(2-methylphenyl)-2-methylthio-6-oxo-1,6-dihydropyrimidine-5-carboxylic acid (8) and 3-[3,5-bis(trifluoromethyl)phenylmethylamino]-1-propanol (3). Treatment of 15 with 1,8-diazabicyclo[5,4,0]undec-7-ene provided 6-[3,5-bis(trifluoromethyl)phenylmethyl]-4-(2-methylphenyl)-2-methylthio-6,7,8,9-tetrahydro-5H-pyrimido[4,5-b][1,5]oxazocin-5-one (6). This intermediate (6) is transformed into the candidate compound (1) by two steps; oxidation, and substitution reaction of the resultant sulfone (7) with 1-acetylpiperazine. This synthetic method is free of chromatographic purification and is amenable to large scale synthesis.
本文描述了一种可规模化合成的路线,以获得 2-(4-乙酰基哌啶-1-基)-6-[3,5-双(三氟甲基)苯基甲基]-4-(2-甲基苯基)-6,7,8,9-四氢-5H-嘧啶并[4,5-b][1,5]恶唑啉-5-酮(1,KRP-103),作为神经激肽(NK)1 拮抗剂。合成的关键步骤是 N-[3,5-双(三氟甲基)苯基甲基]-N-(3-羟基丙基)-4-氯-6-(2-甲基苯基)-2-甲硫基嘧啶-5-甲酰胺(15)的分子内环化、4-(2-甲基苯基)-2-甲硫基-6-氧代-1, 6-二氢嘧啶-5-甲酸 (8) 与 3-[3,5-双(三氟甲基)苯基甲基氨基]-1-丙醇 (3) 形成酰胺。用 1,8-二氮杂双环[5,4,0]十一-7-烯处理 15,可得到 6-[3,5-双(三氟甲基)苯基甲基]-4-(2-甲基苯基)-2-甲硫基-6,7,8,9-四氢-5H-嘧啶并[4,5-b][1,5]恶唑啉-5-酮(6)。该中间体(6)通过两个步骤转化为候选化合物(1):氧化,以及生成的砜类化合物(7)与 1-乙酰基哌嗪发生取代反应。这种合成方法无需色谱纯化,适合大规模合成。