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diazanaphthalene

n. (context organic compound English) Any bicyclic heterocycle formally derived from naphthalene by replacing two carbon atoms with those of nitrogen

Wikipedia
Diazanaphthalene

Diazanaphthalenes are a class of aromatic heterocyclic chemical compounds that have the formula CHN. They consist of a naphthalene double ring in which two of the carbon atoms have been replaced with nitrogen atoms. There are ten positional isomers, which differ by the locations of the nitrogen atoms.

The group consist of two subgroups: