Thiamine hydrochloride

Description of Method. The water-soluble vitamins Bi (thiamine hydrochloride), B2 (riboflavin), B3 (niacinamide), and Be (pyridoxine hydrochloride) may be determined by CZE using a pH 9 sodium tetraborate/sodlum dIhydrogen phosphate buffer or by MEKC using the same buffer with the addition of sodium dodecyl-sulfate. Detection Is by UV absorption at 200 nm. An Internal standard of o-ethoxybenzamide Is used to standardize the method. 

Physical Chemical Characterization. Thiamine, its derivatives, and its degradation products have been fully characterized by spectroscopic methods (9,10). The ultraviolet spectmm of thiamine shows pH-dependent maxima (11). H, and nuclear magnetic resonance spectra show protonation occurs at the 1-nitrogen, and not the 4-amino position (12—14). The H spectmm in D2O shows no resonance for the thiazole 2-hydrogen, as this is acidic and readily exchanged via formation of the thiazole yUd (13) an important intermediate in the biochemical functions of thiamine. Recent work has revised the piC values for the two ionization reactions to 4.8 and 18 respectively (9,10,15). The mass spectmm of thiamine hydrochloride shows no molecular ion under standard electron impact ionization conditions, but fast atom bombardment and chemical ionization allow observation of both an intense peak for the patent cation and its major fragmentation ion, the pyrimidinylmethyl cation (16). 

Thiamine Hydrochloride, MSDS 3834, Hoffmann-La Roche Inc., Nutley, N.J. 

C3NS S — N — — Thiamine hydrochloride monohydrate rhodanine 2-imino-5-phenyl-4-thiazolidinone ... 

To a solution of 20 parts of thiamine hydrochloride in 30 parts of water is added an aqueous solution of sodium hydroxide (7.2 parts of NaOH in 30 parts of water), and the mixture is cooled with water. The mixture is allowed to stand for 30 minutes, 60 parts of chloroform is added, followed by a solution of 30 parts of crude sodium tetrahydrofurfurylthiosulfate in 30 parts of water, and the whole is stirred for 30 minutes. The chloroform layer is separated and the aqueous layer is extracted twice with 20 parts of chloroform. All the chloroform solutions are combined and shaken with 50 parts of 5% hydrochloric acid. The acid solution is decolorized and neutralized with alkali carbonate, whereupon thiamine tetrahydrofurfuryl disulfide separates out in the resinous state but soon solidifies [MP 129 (decomp.)]. The yield is 16 parts. Recrystallization from ethyl acetate gives colorless prisms melting at 132°C (decomp.). 

See also Vitamin Bi Thiamine deficiency, 26 291 Thiamine hydrochloride, 25 795 Thiamine hydrochloride... 

Stock solution 4. 100 x stock solution of vitamins was prepared by dissolving biotin (20 mg), folic acid (20 mg), pyrodoxine hydrochloride (100 mg), riboflavin (50 mg), thiamine hydrochloride (50 mg), nicotinic acid (50 mg), pantothenic acid (50 mg), vitamin B12 (1 mg), 4-aminobenzoic acid (50 mg) and thioctic acid (50 mg) in deionized water. The volume was adjusted to 1.0 L. The solution was filtered, sterilized and stored as 10 mL aliquots at —20 °C. 

Vitamin Bj or thiamine (Figure 19.21) is 3-(4-amino-2-methylpyrimidin-5-ylmethyl)-5-(2-hydroxyethyl)-4-methylthiazolium. It is isolated, synthesized, and used in food supplements and in food fortifications as a solid thiazolium salt in the form of thiamine hydrochloride or thiamine mononitrate [403]. 

A fluorometric method was developed for determination of atmospheric H2O2 simultaneously with other species present at ppbv or lower levels, avoiding chromatographic separation. H2O2 is selectively collected by diffusion through a Nafion membrane, and is carried by a water stream into a reactor where it oxidizes thiamine hydrochloride (117) to a fluorescent ionic form of thiochrome (118), catalyzed by bovine hematin (75b) in alkaline solution, as shown in equation 40. The end solution containing 118 is passed through... 

Strong acid/strong base titrations are used in pharmacopoeial assays of perchloric acid, hydrochloric acid, sulphuric acid and thiamine hydrochloride. 

Argentimetric titration is used in pharmacopoeial assays of sodium chloride and potassium chloride tablets, thiamine hydrochloride, mustine chloride and carbromal. 

Das Gupta, S., Moorthy, M.V., Chowdhri, B.L. and Ghosh, A.K. Effect of thiamine hydrochloride on the blood level of 2-formyl 1-methyl pyridinium oxime chloride (2-PAM.Cl) in rats. 

Josselson, J., Sidell, F.R. 1976. The effect of Intravenous thiamine hydrochloride on pralldoxlme pharmacokinetics In man. EB-TR-76115. 

Josselson, J., Sldell, F.R. 1977. Thiamine hydrochloride as an adjunct to pralidoxlme In a simulated therapeutic setting. EB-TR-76118. 

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