Hexamethylenetetramine, also known as methenamine, hexamine, or urotropin, is a heterocyclic organic compound with the formula (CH2)6N4. 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. Synthesis, structure, reactivity
Hexamethylenetetramine was discovered by Aleksandr Butlerov in 1859. It is prepared industrially by combining formaldehyde and ammonia:
The reaction can be conducted in gas phase and in solution. The molecule has a tetrahedral cage-like structure, similar to adamantane. Four vertices are occupied by nitrogen atoms, which are linked by methylene groups. Although the molecular shape defines a cage, no void space is available at the interior for binding other atoms or molecules, unlike crown ethers or larger cryptand structures. The molecule behaves like an amine base, undergoing protonation and N-alkylation (e.g. quaternium-15). Applications
The dominant use of hexamethylenetetramine is in the production of powdery or liquid preparations of phenolic resins and phenolic resin moulding compounds, where it is added as a hardening component. These products are used as binders, e.g. in brake and clutch linings, abrasive products, non-woven textiles, formed parts produced by moulding processes, and fireproof materials. Medical uses
As the mandelic acid salt (methenamine mandelate) or the hippuric acid salt (methenamine hippurate), it is used for the treatment of urinary tract infection. In an acidic environment, methenamine is believed to act as an antimicrobial by converting to formaldehyde.
Society and culture
Brand names
As of 2016 the drug was available worldwide as drops for ophthalmic use and as tablets, both in various strengths, under many brand names which include: Acustop Cataplasma, Adofeed, Anazin, Anflupin, Anorcid, Ansaid, Antadys, Antafen, Antipain, Baenazin, Benactiv, Biprofin, Biprotec, Bro-Z, Brufen, Brufoz, Cebutid, Clinadol, Coryfin, Dispain, Edolfene, Eyeflur, Falken, Fiera, Flu Ro Fen, Flubifix, Flufen, Flugalin, Flupe, Flur di fen, Fluractive, Fluran, Flurbi Pap, Flurbic, Flurbiprofen, Flurbiprofène, Flurbiprofeno, Flurflex, Flurofen, Fluroptic, Fo Bi Pu Luo Fun, Forphen, Fortine, Froben, Frolix, Fubifen, Fubiprofen, Fubofen, Fukon, Fulruban, Furofen, Kai Fen, Kavoflog, Kotton, Lefenine, Majezik, Maprofen, Maxaljin, Maximus, Meiprofen, Neliacan, Nibelon, Nirolex Gola, Ocufen, Ocuflur, Optifen, Orofaringeo, Painil, Profen, Projezik, Ropion, Sigmaprofen, Stayban, Strefen, Strepfen, Strepflam, Strepsils (various formulations), Sulan, Tie Shr Shu, TransAct, Upnon, Urbifen, Yakuban, Zepolas, Zeralgo, Zero-P, and Zeton. References
Further reading
Dean L (2019). "Flurbiprofen Therapy and CYP2C9 Genotype". In Pratt VM, McLeod HL, Rubinstein WS,  et al. (eds.). Medical Genetics Summaries. National Center for Biotechnology Information (NCBI). PMID 30742399. Bookshelf ID: NBK537365.