the widely used drug cimetidine ( tagamet ) can be nitrosated in the presence of nitrite and under mild acid conditions to form a compound , nitrosocimetidine ( nc ) , which has a chemical structure very similar to those of the mutagens and laboratory carcinogens n-methyl-n'-nitro-n-nitrosoguanidine ( mnng ) and methylnitrosourea ( mnu ) .
C0008783
cimetidine
C0592157
tagamet