Trimethylamine N-oxide Trimethylamine N-oxide Trimethylamine "N"-oxide (TMAO) is an organic compound with the formula (CH)NO. It is in the class of amine oxides. Although the anhydrous compound is known, trimethylamine "N"-oxide is usually encountered as the dihydrate. It is a product of the oxidation of trimethylamine, a common metabolite in animals. Both the anhydrous and hydrated materials are white, water-soluble solids. Trimethylamine "N"-oxide is an osmolyte found in saltwater fishes, sharks, rays, molluscs, and crustaceans. It is considered as a protein stabilizer that may serve to counteract urea, the major osmolyte of sharks, skates and rays. It is also higher in deep-sea
Dihydrogen bond Dihydrogen bond In chemistry, a dihydrogen bond is a kind of hydrogen bond, an interaction between a metal hydride bond and an OH or NH group or other proton donor. With a van der Waals radius of 1.2 Å, hydrogen atoms do not usually approach other hydrogen atoms closer than 2.4 Å. Close approaches near 1.8 Å, are, however, characteristic of dihydrogen bonding. An early example of this phenomenon is credited to Brown and Heseltine. They observed intense absorptions in the IR bands at 3300 and 3210 cm for a solution of (CH)NHBH. The higher energy band is assigned to