6-chloro-3-pyridin-3-yl-[1,2,4]triazolo[4,3-b]pyridazine

3-chloro-6-[4-(2-fluorophenyl)piperazin-1-yl]pyridazine

3-chloro-6-cyclohexylpyridazine

3,6-二氯-4-乙基吡嗪

3,6-二氯-4,5-二乙基吡嗪