First synthesis of novel pentaheterocyclic ring system of 1,2,4-triazolo[2″,3″:6′,1′]pyrimido[4′,5′:2,3]pyrido[1,2-<i>a</i>]benzimidazole
作者:Nehal M. Elwan
DOI:10.1002/jhet.5570410222
日期:2004.3
4-dicarbonitrile (1) with dimethylformamide-dimethylacetal (DMF-DMA) gave 1-[N,N-(dimethylaminomethylene)amino]-3-arylpyrido[1,2-a]benzimidazole-2,4-dicarbonitrile (2). Compounds (1) reacted with triethylorthoformate yielding 1-[N-(ethoxymethylene)amino]-3-arylpyrido[1,2-a]benzimidazole-2,4-dicarbonitrile (3). 3-Amino-4-imino-5-aryl-6-cyanopyrimido[5′,4′:5,6]pyrido[1,2-α] benzimidazole (4) was synthesized
1-氨基-3-芳基吡啶并[1,2- a ]苯并咪唑-2,4-二腈(1)与二甲基甲酰胺-二甲基乙缩醛(DMF-DMA)的反应,得到1- [ N,N-(二甲基氨基亚甲基)氨基] -3 -芳基吡啶并[1,2 - a ]苯并咪唑-2,4-二腈(2)。化合物(1)与原甲酸三乙酯反应,生成1- [ N-(乙氧基亚甲基)氨基] -3-芳基吡啶并[1,2 - a ]苯并咪唑-2,4-二甲腈(3)。通过(2)或(2)的缩合反应合成3-氨基-4-亚氨基-5-芳基-6-氰基嘧啶[5',4':5,6]吡啶[1,2-α]苯并咪唑(4)。(3)与水合肼。的反应(4)用乙酸酐,氯甲酸乙酯或异硫氰酸芳基得到的新环系统的各衍生物即-1,2,4-三唑并- [2“,3”:6',1']嘧啶并[4',5 ′:2,3]吡啶[1,2- a ]苯并咪唑(5-7)。