2,5-DI-(4-PYRIDYL)-S-TETRAZINE

3,6-DI-4-PYRIDYL-1,2,4,5-TETRAZINE

3,6-BIS(4-PYRIDYL)-1,2,4,5-TETRAZINE

3,6-di(pyridin-4-yl)-1,2,4,5-tetrazine