1-Cyano-3-[2-[2-[(N-cyano-N′-methylcarbamimidoyl)amino]ethyldisulfanyl]ethyl]-2-methylguanidine; N-Cyano-3-(cyanoamino)-N′-methyl-7,8-dithia-2,4,11-triazadodec-2-en-12-imidamide (ACI),1-Cyano-3-[2-[2-[(N-cyano-N′-methylcarbamimidoyl)amino]ethyldisulfanyl]ethyl]-2-methylguanidine,Impurity in commercial preparations of Cimetidine.,Cimetidine Therapeutic