6,7-Dihydro-6-hydroxydipyrido[1,2-a:2′,1′-c]pyrazinium dibromide and dipyrido[1,2-a:2′,1′-c]pyrazinium dibromide are reduced in aqueous solution by a one-electron transfer to give stable radical cations. In the case of the latter salt the one-electron transfer is largely reversed by atmospheric oxidation.