Hexamethylenetetramine ((CH2)6N4, or C6H12N4), (urotropin, hexamin, English: Methenamine (INN), 1,3,5,7-tetraazaadamantane, hexamethylenetetramine or hexametylenetetramine). Methenamin is applied in medicine under the international unlicensed name (IUN).
It is applied in production of phenol-formaldehyde resins
In the food industry it is registered as additive preservative (E239 code). It is often applied in cheese making, and also to preservation of caviar