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 complex separations > 1 Å are better described as dihydride complexes (see figure). The usual method for characterization is H NMR spectroscopy. The magnitude of spin-spin coupling, "J", is a useful indicator of the strength of the bond between the hydrogen and deuterium in HD complexes. For example, "J" is 43.2 Hz in HD but 33.5 Hz in W(HD)(CO)(PPr). Dihydrogen complexes typically have shorter H-spin-lattice relaxation times than the corresponding dihydrides. An ideal if nontrivial method of characterization of dihydrogen complexes is neutron diffraction. Neutrons interact strongly with hydrogen atoms, which allows one to infer their location in a crystal. In