Glucitol synthesis

The sugar alcohol anhydride polygalitol, 1,5-anhydro-D-glucitol, may be prepared from the root of Poly gala Senega L.49 The process is, however, a time-consuming one and chemical synthesis of the substance by Raney... 

Lemer (29) reported a simple synthesis of L-erythrose that involves 2,3-di-O-isopropylidene-D-gulono-1,4-lactone (7b) as a key intermediate. Reduction of the lactone group of 7b with sodium borohydride, followed by periodate oxidation of the L-glucitol derivative, afforded 2,3-O-isopropy-lidene-L-erythrose. The free sugar may be readily obtained by acidic hydrolysis of the latter. 

G. W. J. Fleet, P. W. Smith, R. J. Nash, L. E. Fellows, R. B. Parekh, and T. W. Rademacher, Synthesis of 2-acetamido-l,5-imino-l,2,5-trideoxy-D-mannitol and of 2-acetamido-l,5-imino-l,2,5-trideoxy-D-glucitol, a potent and specific inhibitor of a number of P-N-acetylglucosaminidases, Chem. Lett. (1986) 1051-1054. 

K. Dax, V. Grassberger, and A. E. Stiitz, Simple synthesis of l,5,6-trideoxy-l,5-imino-D-glucitol, the first fluorine-containing derivative of glucosidase inhibitor 1-deoxynojirimycin, J. Carbohydr. Chem., 9 (1990) 903-908. 

J. Di, B. Rajanikanth, and W. A. Szarek, Fluorinated l,5-dideoxy-l,5-iminoalditols Synthesis of l,5,6-trideoxy-6-fluoro-l,5-imino-D-glucitol (l,6-dideoxy-6-fluoronojirimycin) and 1,4,5-trideoxy-4-fluoro-l,5-imino-D-ribitol (l,2,5-trideoxy-2-fluoro-l,5-imino-L-ribitol), J. Chem. Soc., Perkin Trans. 1 (1992)2151-2152. 

In a different synthesis of 1,5-anhydrohexitols from a compound having a pyranoid ring, Lehmann and Friebolin31 treated 1,5-anhydro-2-deoxy-D-arafemo-hex-l-enitol (D-glucal) (20) with a-toluenethiol in the presence of light, and obtained l,5-anhydro-2-S-benzyl-2-thio-D-mannitol (21) and the epimeric anhydro-D-glucitol in equal amounts. 

Tri-0-acetyl-l,5-anhydro-2-deoxy-D-arabino-hex-l-enitol (tri-O-acetyl-D-glucal) was the starting point for the synthesis of 1,5-anhy-dro-2-chloro-2-deoxy-D-glucitol or -D-mannitol by way of the 1,2-dichloride (22), which was reduced32 by means of lithium aluminum hydride to the 2-chloro-2-deoxy derivative (23). That the chlorine... 

The synthesis of an alditol having a 4-membered (oxetane) ring was first reported by Ustyuzhanin and coworkers,50 who prepared 1,3-anhydro-5,6-di-0-methyl-2,4-0-methylene-D-glucitol by saponification of the 1-p-toluenesulfonate of the corresponding derivative of D-... 

In the synthesis of 1,6-anhydro-D-glucitol, at least, a 2,6-anhydride is a byproduct.53 Its structure was assigned on the basis of its i.r. spectrum, in comparison with those of the 1,6- and 1,5-anhydro-D-glucitols, and the fact that no diglycolic acid was obtained after periodate oxidation followed by oxidation with hypobromite. 

D-Glucitol (Sorbitol or Hexanhexol), HOCH2(CHaOH)4CH2OH raw 182.17, ndls (with lA or 1 w), tnp about ll0°(dry), -100° or less (with w), very hygr when dry sol in w hot ale. Found in various fruits prepd by sodium amalgam reduction of d-sorbose or by pressure hydrogenation of dextrose with Ni catalyst. Used far prepn of ascorbic acid (Vitamin C), for synthesis of resins, surface-active agents, varnishes, syrups, cosmetic creams aod for explosive Sorbitol Hexanitrate... 

Yurkevich and his colleagues presented evidence of some novel controls on the synthesis and secretion of /3-D-fructofuranosidase by strains of Saccharomyces cerevisiae. Addition of D-mannitol to give a concentration of 0.5 M in the medium increased the concentration of /3-D-fructofuranosidase in Saccharomyces (globosus) cerevisiae. Similar results were obtained with D-glucitol and D-xylose. As this increase was inhibited by 36 pM cycloheximide, Yurkevich and Khamani168 concluded that a change to a hypertonic medium caused an increase in de novo biosynthesis of /3-D-fructofuranosidase. 

Regtosdective reduction of an epoxide. A key step in a short synthesis of (+)-muscarine (6) from the dibenzoate of 2,5-anhydro-D-glucitol (1) involves reduction of the epoxide 2. Use of SMEAH gives a 12 1 mixture of 3 and 4 use or LiAlH4 gives the same diols in the ratio 3 1. ... 

The paradigmatic hexosaminidase inhibitor with basic nitrogen in the ring, 2-acetamido-1,2-dideoxynojirimycin (2-acetamido-l,2,5-trideoxy- 1,5-imino-D-glucitol, 33) has not been found naturally to date. This inhibitor was first prepared by Fleet and co-workers [76,77] in a 17-step synthesis from D-glucose via methyl 3-0-benzyl-2,6-dideoxy-2,6-imino-a-D-mannopyranoside together... 

A different approach for the synthesis of di-O-methylisosorbide and other lower di-0-alkylated derivatives, using chloromethane in different solvent systems, with or without the aid of additional phase-transfer catalysts, was the subject of a patent application.181 In addition, a one-vessel dehydration -methylation reaction starting from D-glucitol was mentioned. Mixtures of mono- and di-O-methylisosorbide resulted on alkylation of the diol with... 

In summary, the synthesis of L-ascorbic acid (1, see Scheme 4) by way of D-glucose (8) -> D-glucitol (24) -> L-sorbose (25) -> 2,3 4,6-di-0-isopropylidene-L-xi/(o-2-hexulofuranose (26) -> 2,3 4,6-di-0-iso-propylidene-L-xy(o-2-hexulofuranosonic acid (27) -> 1 may be achieved in excellent yield in commercial practice, it affords 1 in >50% overall yield.255 During the course of the development of this synthesis, a number of papers were published in which the whole sequence was performed, and the overall yield reported. In 1934, the over-... 

It may be noted that l,2,3,4-tetra-0-benzoyl-5,6-0-isopropylidene-D-glucitol (52) has been oxidized with trityl tetrafluoroborate324 325 to 3,4,5,6-tetra-O-benzoyl-keto-L-sorbose (53) in 50% yield. This illustrates an interesting oxidation of acetals, and constitutes a partial, chemical synthesis of L-sorbose (25) from D-glucitol (24). 

All synthetic efforts directed towards the synthesis of L-ascorbic acid that have thus far been presented began with the reduction of D-glucose (8) to D-glucitol (24), followed by oxidation atC-5 and C-6. An alternative approach to the synthesis of L-ascorbic acid is first to convert D-glucose (or its equivalent) into D-glucuronic acid (54) (or its equivalent), followed by reduction of 54 at G-1 and then oxidation at C-5, or oxidation of 54 first at C-5 and then reduction at C-l. These options are shown in Scheme 7 in both, formation of L-oty/o-2-hexulo-sonic acid (28) (or its equivalent) results. In this Section, several approaches to the synthesis of L-ascorbic acid that proceed through an intermediate equivalent to 55 will be presented. 

Uniformly labelled 1 was prepared by the Reichstein-Griissner synthesis (see Scheme 4), starting with unifonnly labelled D-glu-cose.597-599 L-[2,3,4,5,6-14C]Ascorbic acid was prepared 800 from L-[U-14C]xylose by way of L-threo-pentos-2-ulose (9) (see Scheme 2). The L-[U-14C]xylose was prepared from D-[U-,4C]glucitol by using the route shown in Scheme 21. 

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