Naturally occurs as the L-form in a variety of vegetables. Although used in food as a flavoring ingredient in fish products, it has also been used therapeutically in the treatment of peptic ulcers, colitis and gastritis.
Reported found in asparagus, cabbage, cabbage juice, celery, sweet corn, milk, potato, tea, green tea and
tomato.
A derivative of L-Methionine (M260440). Naturally occurring sulfonium compound found in a large number of plants. Identification of antiulcer vitamin in cabbage leaves. Antiulcerative.
ChEBI: Methylmethionine sulfonium salt is an organic molecular entity.
Methiosulfonium chloride is used for its protective effect on the liver and gastrointestinal mucosa, whereas the iodide finds use for rheumatic disorders.
298 g dl-methionine, 2000 ml water and 151.1 methyl chloride were put into autoclave (volume 3 L) made from V4-a steel. The mixture was heated at temperature 50°-55°C for 8 hours and pressure 12-13 atmospheres.
On cooling an excess of methyl chloride was evaporated, the slightly yellow residue was mixed with 0.2% activated coal and filtered. Water was evaporated in vacuum at 45°-55°C. 2 L methanol was poured into an almost colorless syrup obtained, cooled to -5°-(-10°)C. The methylmethioninesulfonium chloride crystallized.
It was filtered off to give 340 g (85.3%) of desired product 99.5 % purity (data of thin-layer chromatography).
Taste characteristics at 5 ppm: sulfureous creamy, tomato, malty, vegetable like
Chloride: Ardesyl (Beytout, France), withdrawn from the market; Cabagin (Kowa, Japan). Iodide: Lobarthrose (Opodex, France), withdrawn from the market.
Likely impurities are methionine, methionine sulfoxide and methionine sulfone. Crystallise Vitamin U from water by adding a large excess of EtOH. It is hygroscopic. It should be stored in a cool, dry place and protected from light. It has also been purified on a column of Dowex 50 H+ form, washed with H2O and eluted with 6N ammonia, lyophilised, the residue is dissolved in dilute HCl, lyophilised again and then it is obtained as colourless prisms by vapour diffusion of Et2O in a 1:1 (v/v) mixture of MeOH/EtOH in which the hydrochloride is dissolved [Del Re Acta Cryst B 33 3289 1977]. The iodide salt, m ~ 150o(dec), is obtained by dissolving it in 50% aqueous EtOH and adding ~3.5 volumes of absolute EtOH. The bromide salt has m 140o(dec) [Toennies & Kolb J Amer Chem Soc 67 849 1945].
