Hexamethylenetetramine, also known as methenamine, hexamine, or its trade name Urotropin, is a heterocyclic organic compound with the formula (CH)N.  This white crystalline compound is highly soluble in water and polar organic solvents.  It has a cage-like structure similar to adamantane.  It is useful in the synthesis of other organic compounds, including plastics, pharmaceuticals, and rubber additives. It sublimes in vacuum at 280 °C.