Advances in the synthesis of non-annelated polynuclear heterocyclic systems comprising the 1,2,5-oxadiazole ring

This review is concerned with recently developed synthetic methods for non-annelated polynuclear heterocyclic systems that incorporate, along with a furazan and(or) furoxan ring, polynitrogen and nitrogen – oxygen heterocycles (1,2,4- and 1,3,4-oxadiazole, 1,2,3- and 1,2,4-triazole, tetrazole, pyrazole, sym-triazine, 1,2,4,5-tetrazine and so on) linked via C–C or C–N bonds or heteroatomic $[\text{N},\text{O},\text{S},\text{N}==\text{N}]$ bridges. Methods for preparing assemblies in which a furazan ring and(or) a furoxan ring are linked to one another by C–C bonds or heteroatoms (N, O, S) are surveyed. Potential applications of the synthesized structures as pharmacologically active and high-energy compounds are discussed.

The bibliography includes 266 references. (review)