Abstract
Reaction of 2-aminobenzimidazole with aroylisothiocyanates gave 2-aroylaminobenzimidazoles ( 3 ) and N-aroyl-N′-(benzimidazol-2-yl)-thioureas ( 4 ). The products obtained on reaction of 4 with PCl5 in POCl3, and with oxidising agents have been identified as 4-arylbenzimidazolo[1,2-a]-s-triazin-2-ones ( 5 ) and 2-aroylamino-benzimidazolo[1,2-b]-1,2,4-thiadiazolines ( 7 ) respectively.