Substituted benzimidazoles and structurally related compounds are of pharmacological and therapeutical interest. 1 In some cases, bioisosteric replacement within the benzimidazole scaffold leading to imidazo[4,5-b]pyridines resulted in improved properties as compared to the corresponding parent compound. 2 Their preparation resulted from reaction of a primary amine with 2-chloro-3-nitropyridine 1. The resulting 2-aminopyridine intermediate was N-acylated ( ...