Synthesis and biological activity of fluorinated 2-amino-4-aryl-3,4-dihydro[1,3,5]triazino[1,2-a]benzimidazoles

Synthesis of ethyl 6‐aryl‐4‐oxo‐4,6‐dihydro‐1(12)(13)h‐pyrimido‐[2′,1′:4,5][1,3,5]triazino[1,2‐a]benzimidazole‐3‐carboxylates

“…The synthesis of ethyl 6-aryl-4-oxo-4,6-dihydro-1(12)(13)H-pyrimido [2',1':4,5] [1,3,5]triazino [1,2-a]benzimidazole-3-carboxylates (4a-p) was described via pyrimidine ring annulation to 4-aryl-3,4-dihydro[1,3,5]triazino [1,2-a]benzimidazole-2-amines (2a-p) which were obtained from 2-guanidinobenzimidazole (1). Tautomerism in the prepared compounds was investigated using nmr spectroscopy.…”

“…Heterocyclic compounds with 1,3,5-triazino [1,2-a]benzimidazole nucleus have been reported to possess a variety of biological effects [2][3][4][5][6][7][8][9][10][11][12][13]. Our laboratory has been working on the synthesis and biological evaluation of new fused 1,3,5-triazines with a particular interest in 1,3,5-triazino [1,2-a]benzimidazoles because of their potential antifolate activity [1][2][3].…”

“…Our laboratory has been working on the synthesis and biological evaluation of new fused 1,3,5-triazines with a particular interest in 1,3,5-triazino [1,2-a]benzimidazoles because of their potential antifolate activity [1][2][3]. In this report we describe the synthesis of a new fused four-ring heterocyclic compounds bearing the 1,3,5-triazino [1,2-a]benzimidazole nucleus.…”

“…The synthesis of 3,4-dihydro [1,3,5]triazino[1,2-a]-benzimidazole-2-amines through a base catalyzed cyclization of 2-guanidinobenzimidazole (1) with benzaldehyde was first reported by Nagarajan et al in 1970 [23]. Using 1, a variety of aromatic aldehydes and piperidine as a catalyst, we have prepared a library of 4-aryl-3,4-dihydro[1,3,5]triazino [1,2-a]benzimidazole-2-amines (2a-p) (Scheme 1).…”

“…The reaction of the prepared 4-aryl-3,4-dihydro[1,3,5]triazino [1,2-a]benzimidazole-2-amines (2a-p) with diethyl ethoxymethylenemalonate afforded the formation of ethyl 6-aryl-4-oxo-4,6-dihydro-1(12) (13)H-pyrimido- [2',1':4,5] [1,3,5]triazino [1,2-a]benzimidazole-3-carboxylates (4a-p) (Scheme 2).…”