<unk> , also called hexamethylenetetramine or methenamine (INN), is a heterocyclic organic compound that can be prepared by the reaction of formaldehyde and ammonia.  It is crystalline and white in appearance.  Particle size ranges from 80-800 micrometres.  It is moderately soluble in water and very soluble in most organic solvents.  It has a cage-like structure similar to adamantane.
It has two very different types of uses: as an antibiotic (commonly the hippurate salt, methenamine hippurate), and as a solid fuel tablet used for cooking while camping or hiking. The name methenamine is more common in its medicinal uses and<unk>  is more common in commercial uses.
Hexamine
Diethylpropion
Benzalkonium chloride
Methylpentynol
Metomidate
Tritoqualine
Benzoctamine
Methohexital