Synthesis of detomidine and medetomidine metabolites: 1,2,3-trisubstituted arenes with 4′(5′)-imidazolylmethyl groups
作者:Ivan Stoilov、David S. Watt、Jack P. Goodman、Jan S. T. Pyrek
DOI:10.1002/jhet.5570300631
日期:1993.12
undergo rapid oxidative metabolism at the aromatic methyl group distal to the imidazole ring. In the detomidine series, the addition of a Grignard reagent prepared from 2-((3′,4′-dimethoxyphenyl)methoxy)methyl)-6-bromotoluene (13) to imidazole-4(5)-carboxaldehyde (7) provided 2-(((3′,4′-dimethoxyphenyl)methoxy)methyl)-6-(1′-hydroxy-1′-(5′-imidazolyl)methyl)tolulene (14). In a subsequent reduction,
两种合成策略允许合成地托米定(1)和美托咪定(4)的各种代谢物,它们是有效的α-2肾上腺素受体激动剂,在咪唑环远端的芳族甲基上经历快速的氧化代谢。在地托米定系列中,将由2-(((3',4'-二甲氧基苯基)甲氧基)甲基)-6-溴甲苯(13)制备的格利雅试剂添加到咪唑4(5)-甲醛(7)中2 -((((3',4'-二甲氧基苯基)甲氧基)甲基)-6-(1'-羟基-1'-(5'-咪唑基)甲基)甲苯(14)。在随后的还原中,可以区分仲苄基羟基和被保护为3,4-二甲氧基苄基醚的伯苄基羟基。除去保护基,提供了3-(羟甲基)全胃苷(3-HD)(2)和氧化生成的3-羧基全胃苷(3-CD)(3)。然而,在美托咪定系列中,类似的2-((((3',4'-二甲氧基苯基)甲氧基)甲基)-6-(1'-羟基-1'-甲基-1'-(5'-咪唑基)的氢解反应)甲基)甲苯(17)失效,需要另外的更长的脱水和还原途径来确保3-(羟