A series of 1,4-diacetyl-1,4-dihydropyrazines fused with two bornene, cyclopentene, and cyclohexene rings were prepared by the reduction of the corresponding pyrazines with zinc powder in the presence of aceticanhydride. Cyclic voltammetry measurements revealed that the oxidation potentials of the dihydropyrazines decrease in the order of cyclohexene-, bornene-, and cyclopentene-fused derivatives