Studies on the Mechanism of 1,2-Dihydropyrazin-2-one Ring Formation from Dipeptidyl Chloromethyl Ketone and Its Chemical Properties: Immediate Deamination during Catalytic Hydrogenation
作者:Anna Miyazaki、Yutaka Fujisawa、Kimitaka Shiotani、Yoshio Fujita、Tingyou Li、Yuko Tsuda、Toshio Yokoi、Sharon D. Bryant、Lawrence H. Lazarus、Yoshio Okada
DOI:10.1248/cpb.53.1152
日期:——
1,2-Dihydropyrazin-2-one derivatives, which have two aminoalkyl groups at the positions 3 and 6, were found to be efficient tools for the construction of potent, selective and long-acting opioid mimetics. During the course of preparation, we found that the catalytic hydrogenation of 3,6-bis(benzyloxycarbonylaminomethyl)-5-methyl-1,2-dihydropyrazin-2-one to remove the benzyloxycarbonyl groups resulted in a side reaction. By MS and NMR studies and by preparation of additional 1,2-dihydropyrazin-2-one derivatives, the structure of the by-product was identified as 3-aminomethyl-5,6-dimethyl-1,2-dihydropyrazin-2-one. Preparation of additional compounds substituted with deuterium provided us with sufficient information to confirm the structure of the product and to support a cyclization mechanism in its formation.
在3和6位具有两个氨基烷基团的1,2-二氢吡嗪-2-酮衍生物被发现是构建强效、选择性和长效类吗啡模拟物的有效工具。在准备过程中,我们发现3,6-双(苄氧羰基氨基甲基)-5-甲基-1,2-二氢吡嗪-2-酮的催化氢化以去除苄氧羰基基团导致了副反应。通过质谱和核磁共振研究以及制备额外的1,2-二氢吡嗪-2-酮衍生物,副产物的结构被鉴定为3-氨基甲基-5,6-二甲基-1,2-二氢吡嗪-2-酮。制备含有氘的额外化合物为我们提供了足够的信息以确认产物的结构并支持其形成的环化机制。