Nitrogen Rich Heterocycles as a Privileged Fragment in Lead Discovery

Nitrogen rich heterocycles such as pyrazole, imidazole, triazoles, tetrazole, triazines and their fused systems including imidazotriazines and triazolotriazines have been attracted medicinal chemists because of their prominent biological activities. Due to the presence of nitrogens as an electronegative atom, these heterocycles are capable of constituting various strong bonds. This capability has provoked the scientists to incorporate these fascinating fragments into their designed drug like molecules. This review attempts to summarize various pharmacological activities of nitrogen rich heterocyclic systems.