Diazine

In organic chemistry, diazines are a group of organic compounds having the molecular formula C4H4N2. Each contains a benzene ring in which two of the C-H fragments have been replaced by isolobal nitrogen. There are three structural isomers:
 * pyridazine (1,2-diazine) [[image:Pyridazin.svg|45px]]
 * pyrimidine (1,3-diazine) [[image:Pyrimidin.svg|45px]]
 * pyrazine (1,4-diazine) [[image:Pyrazin.svg|45px]]