A facile synthesis of 5,7-dihydro-5-oxopyrido[3′,2′:5,6]pyrimido[1,2-<i>a</i>]benzimidazoles. A new heterocyclic ring system
作者:Paola Caroti、Carlo Ceccotti、Antonio Da Settimo、Fabio Palla、Giampaolo Primofiore
DOI:10.1002/jhet.5570230645
日期:1986.11
2-chloropyridine-3-carbonyl chloride and 1-alkyl-2-aminobenzimidazoles afforded the N-(1-alkylbenzimidazole-2-yl)-2-chloropyridine-3-carboxamides, which were cyclized to 5,7-dihydro-5-oxopyrido[3′,2′:5,6]pyrimido[1,2-a]benzimidazoles. The assigned structures of these hitherto unknown heterocyclic compounds were confirmed by their ir and 1H nmr spectra and chemical evidence.
2-氯吡啶-3-羰基氯与1-烷基-2-氨基苯并咪唑之间的反应,得到N-(1-烷基苯并咪唑-2-基)-2-氯吡啶-3-羧酰胺,将其环化为5,7-二氢- 5-氧吡喃并[3',2':5,6]嘧啶并[1,2- a ]苯并咪唑。这些迄今未知的杂环化合物的指定结构已通过其ir和1 H nmr光谱和化学证据得以证实。