Synthesis of ascorbic acid

Chemical Synthesis. The first synthesis of ascorbic acid was reported ia 1933 by Reichsteia and co-workers (14,39—42) (Fig. 4). Similar, iadependent reports pubHshed by Haworth and co-workers followed shordy after this work (13,43—45). L-Xylose (16) was converted by way of its osazone (17) iato L-xylosone (18), which reacted with hydrogen cyanide forming L-xylonitfile (19). L-Xylonitfile cyclized under mild conditions to the cycloimine of L-ascorbic acid. Hydrolysis of the cycloimine yielded L-ascorbic acid. The yield for the conversion of L-xylosone to L-ascorbic acid was ca 40%. 

Figure 20.7 The industrial synthesis of ascorbic acid from glucose.

Oluwafemi O. S., Revaprasadu N and Adeyemi O. O. (2010). A facile "green" synthesis of ascorbic acid-capped ZnSe nanoparticles. Colloids Surf B Biointerfaces, 79,126-130. 

Haworth, W.N. Hirst, E.L. (1933) Synthesis of Ascorbic Acid. Chemistry Industry (London), 645-646. 

The reaction of D-glucosone and other osones with cyanide, as a first stage in the synthesis of ascorbic acid and its analogs, has been reviewed by Smith.136... 

Moreau, R. Dabrowski, K. (1998) Body pool and synthesis of ascorbic acid in adult sea lamprey (Petromyzon marinus) an agnatan fish with gulonolactmie oxidase activity. Proc. Natl. Acad. Sci. USA, 95,10279-82. 

Danehy, J. P. 1981. Synthesis of ascorbic acid from lactose. U.S. Patent 4,259,443. 

L-Sorbose plays an important part as an intermediate in the synthesis of ascorbic acid (vitamin C). Reichstein and Griissner100 achieved this synthesis by the oxidation of 2,3 4,6-diisopropylidene-L-sorbose (XLVI) to the corresponding keto-L-gulonic acid derivative (XLVII), which gave 2-keto-L-gulonic acid (XLVIII) on hydrolysis. Isomerization produced ascorbic acid identical with the natural vitamin. 

The Primary Product of the Synthesis of Ascorbic Acid and its Analogues, W. N. Haworth and E. L. Hirst, Helv. Chim. Acta, 17, 520 (1934). 

Biotin -member of the B-complex family Water soluble Metabolism of fats synthesis of ascorbic acid healthy skin hair balding and greying. Soya beans, brown rice, nuts, fruit, brewer s yeast and milk. It can be synthesised by intestinal bacteria. 100 pg No... 

Synthesis of Ascorbic acid and of Disaccharides (i) The synthesis of Vitamin C (75), ascorbic acid from D-galactose (ref.72) and that from D-glucose (ref.73) were described in the same year which also saw the development of the the latter as an industrial route. Sorbitol obtained by the reduction of D-glucose was oxidised with the bacterium Acetobacter suboxvdans to L-sorbose which as the bis-acetonylidene derivative was next oxidised to the corresponding acid, L-2-oxogulonic acid, the methyl ester of which was base-catalysed to afford the final product as illustrated. 

The phosphorylation of ascorbic acid under basic conditions has been studied extensively. The synthesis of ascorbic acid 2-phosphate, 22, has been reported by Seib et al. (9) via treatment of 5,6-O-isopropylidene ascorbic acid, with phosphorus oxychloride under highly basic conditions (pH 12). Hydrolysis of the ketal protecting group of the 2-phosphate intermediate 20 affords the 2-O-phosphate 22, whose structure has been... 

The direct extrapolations from animals that synthesize ascorbic acid to a 70-kg human ignores the observations that in large animals the synthesis of ascorbic acid only accounts for a small fraction of the L-gulonate oxidized (132), Also, extrapolation to 70 kg of body weight should first correct for differences in metabolic body size the correction should include (wtkg ), which is appropriate in many instances (133),... 

Sunlight is not necessary for the synthesis of ascorbic acid in plants but is needed to produce optimal vitamin C concentrations. Photosynthesis produces the precursor hexoses needed for ascorbic acid synthesis (38,51),... 

Reactions with sulfur trloxlde. Sulfur trloxlde (SO3) may react violently with nucleophiles unless the conditions are well controlled and this route Is not commmonly used for syntheses of xenobiotic sulfate conjugates. However a method suitable for both macro and micro scale synthesis of ascorbic acid 2-P sj sulfate (Figure 6A) was recently reported where the SO3 was Introduced to the substrate dissolved In DMF at -180"C (7 ). The reaction was completed at -15 C In 30 min and gave a 74Z yield of the 2-0-sulfate. 

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