Page 230 - Chemical and process design handbook

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CIMETIDINE

Cimetidine, a highly substituted guanidine, is sold as Tagamet, and is
widely used as an antiulcer medication. It acts by blocking the histamine
molecules in the stomach from signaling the stomach to secrete acid.
Cimetidine is manufactured by the action of a substituted guanidine on
an amino-thio compound in the presence of methyl cyanide.
CH NHCSCH + NH CH CH SCH Z → CH NHCNHCH CH SCH Z
3 3 2 2 2 2 3 2 2 2

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