Tetrazine

Tetrazine is a compound that consists of a six-membered aromatic ring containing four nitrogen atoms with the molecular formula C2H2N4.

Three core-ring isomers exist: 1,2,3,4-tetrazines, 1,2,3,5-tetrazines, and 1,2,4,5-tetrazines, also known as v-tetrazines, as-tetrazines and s-tetrazines respectively.

[1] 1,2,3,4-Tetrazines are often isolated fused to an aromatic ring system and are stabilized as the dioxide derivatives.

[citation needed] Heavily substituted tetrazines form the verdazyls, a family of stable radicals.

[3] Protected tetrazines are strong acetylene acceptors in Diels-Alder equilibria.