709030-32-0Relevant articles and documents
First Synthesis of Novel Pentaheterocyclic Ring System of 1,2,4-Triazolo[2″,3″:6′,1′]pyrimido [4′,5′ :2,3]pyrido[1,2-a]benzimidazole
Elwan, Nehal M.
, p. 281 - 284 (2007/10/03)
Reaction of 1-amino-3-arylpyrido[1,2-a] benzimidazole-2,4-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-a] benzimidazole (4) was synthesized via condensation of either (2) or (3) with hydrazine hydrate. Reactions of (4) with acetic anhydride, ethyl chloroformate or aryl isothiocyanate yielded the respective derivative of the new ring system namely 1,2,4-triazolo[2″,3″:6′,1′]pyrimido[4′ ,5′:2,3]pyrido[1,2-a]benzimidazole (5-7).