Synthesis of Substituted Imidazo[1,5-a]pyrimidines, 1H-pyrrolo[2,3- b]pyridines and 3-methyl-3H-imidazo[4,5-b]pyridines
作者:Jingshing Wu、Xuechao Xing、Gregory Cuny
DOI:10.2174/157017809787893000
日期:2009.4.1
various malondialdehydes or 1,3-diketones gave substituted imidazo[1,5-a]pyrimidines. However, cyclization of 2-aminopyrroles and 5-amino-1-methylimidazoles resulted in condensations on a carbon atom of the heterocyclic ring instead of nitrogen generating 1H-pyrrolo[2,3- b]pyridines (i.e. 7-azaindoles) and 3-methyl-3H-imidazo[4,5-b]pyridines, respectively. In these cases the addition of pyrrolidine to the
原位生成的5-氨基咪唑与各种丙二醛或1,3-二酮环化,得到取代的咪唑并[1,5-a]嘧啶。然而,2-氨基吡咯和5-氨基-1-甲基咪唑的环化导致杂环碳原子上的缩合而不是氮的生成1H-吡咯并[2,3-b]吡啶(即7-氮杂吲哚)和3-甲基-3H-咪唑并[4,5-b]吡啶。在这些情况下,在氨基与丙二醛或1,3-二酮的羰基之一之间初步缩合后,向反应混合物中添加吡咯烷可显着提高1H-吡咯并[2,3-b]吡啶的收率和3-甲基-3H-咪唑并[4,5-b]吡啶。