含氮杂环在药物和类药物化合物中无处不在;然而,区域选择性合成已被证明具有挑战性。在此,我们报告了我们为开发合成吡唑并[1,5- a ]吡啶的区域选择性方法所做的努力,并偶然发现了一种用于区域选择性形成咪唑并[1,5- a ]吡啶的方案。总之,这些转化允许从一个共同的中间体快速和选择性地形成两个重要的杂环基序。
A Versatile Annulation Route to Primary-Amino-Substituted Naphthyridine Esters
摘要:
A straightforward four-step synthesis of primary-amino-substituted naphthyridine esters from commercially available cyanopyridines was described. The route makes use of a condensation reaction between pyridinyl acetates with N,N-dimethylformamide dimethylacetal (DMF-DMA) to form ortho-cyano vinylogous carbamates. These intermediates can undergo facile cyclization with ammonium acetate in acetic acid to generate the corresponding naphthyridine esters in good synthetic yields. The synthesis of primary-amino-substituted 7-azaquinoxaline was also described.