3-(((2-((Diaminomethylene)amino)thiazol-4-yl)methyl)thio) propanamide|3-(((2-((diaminomethylene)amino)thiazol-4-yl)methyl)thio)propanamide ;|3-[[[2-[(Diaminomethylene)amino]thiazol-4-yl]methyl]sulphanyl]propanamide HCl salt|Famotidine Amide Impurity|Famotidine USP RC D ; 3-[[[2-[(Diaminomethylene)amino]thiazol-4-yl]methyl]sulphanyl]propanamide.|USP Famotidine Related Compound C;|USP Famotidine Related Compound D