the two nitrogen atoms of the functional groups being doubly-bound to each other, e.g. azoformamide

Derivatives of carbonic acid containing functional groups covered by groups in which at least one nitrogen atom of these functional groups is further bound to another nitrogen atom not being part of a nitro or nitroso group > the two nitrogen atoms of the functional groups being doubly-bound to each other, e.g. azoformamide

Derivatives of carbonic acid containing functional groups covered by groups C07C269/00 - C07C279/00 in which at least one nitrogen atom of these functional groups is further bound to another nitrogen atom not being part of a nitro or nitroso group > the two nitrogen atoms of the functional groups being doubly-bound to each other, e.g. azoformamide