Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate3,5-二氨基-6-氯吡嗪-2-羧酸甲酯Methyl 3,5-diamino-6-chloropyrazine-2-carboxylate3,5-Diamino-6-chloropyrazine-2-carboxylic Acid Methyl EsterMethyl 3,5-Diamino-6-chloropyrazinecarboxylate3,5-Diamino-6-chloro-2-pyrazinecarboxylic Acid Methyl Ester