<i>N</i>-Hydroxyamide-Containing Heterocycles. Part 2. Synthesis and Iron(III) Complex-Forming Tendency of 1-Hydroxy-2(1<i>H</i>)-pyrimidinone and -pyrazinone
作者:Junko Ohkanda、Takeshi Tokumitsu、Keiryo Mitsuhashi、Akira Katoh
DOI:10.1246/bcsj.66.841
日期:1993.3
4-dimethoxy-2-butanone, and 2,4-pentanedione under acidic conditions gave the corresponding 1-benzyloxy-2(1H)-pyrimidinones (3 and 3′) in moderate yields. In contrast, the reaction of N-(benzyloxy)urea or N-methoxyurea with 1-phenyl-1,3-butanedione exclusively gave 3-alkoxyimino derivatives (4). 1-Benzyloxy-2(1H)-pyrazinones (9a and 9b) were synthesized via three steps starting from N-(t-butoxycarbonyl)glycine
N-(苄氧基)脲与1,1,3,3-四乙氧基丙烷、4,4-二甲氧基-2-丁酮和2,4-戊二酮在酸性条件下反应得到相应的1-苄氧基-2(1H) -嘧啶酮(3 和 3'),产率适中。相反,N-(苄氧基)脲或N-甲氧基脲与1-苯基-1,3-丁二酮的反应仅产生3-烷氧基亚氨基衍生物(4)。1-苄氧基-2(1H)-吡嗪酮(9a 和 9b)从 N-(叔丁氧基羰基)甘氨酸开始,通过三个步骤合成。化合物 3c、9a 和 9b 在乙酸中加氢或用 30% HBr 处理得到 1-羟基-4,6-二甲基-2(1H)-嘧啶酮 (HOPY) 和 1-羟基-(HOPR-H)和 1-羟基-5,6-二甲基-2(1H)-吡嗪酮 (HOPR-Me)。它们在酸性区域与 N-羟基酰胺基团形成铁 (III) 的 3:1 络合物,