Glucitol structure

Fig. 2. Structures of hexitols (a) allitol, (b) sorbitol (D-glucitol), (c) D-maimitol, (d) dulcitol, (e) L-iditol, and (f) D-altritol.

There are solitary examples of other alditol phosphates as components of this class of polymers. Arabinitol 1-phosphate is part of the S. pneumoniae type 17F capsular polysaccharide. o-Glucitol 6-phosphate is a component of the group-specific polysaccharide from group B Streptococcus, which has a most unusual, ramified structure. In a polysaccharide from Nocardia... 

Brigl and Griiner45 reported the isolation of three products when 1,6-di-O-benzoyl-D-mannitol (29) was heated in boiling 1,1,2,2-tet-rachloroethane in the presence of p-toluenesulfonic acid as the catalyst. These compounds were assigned mono- and di-anhydro structures, and were later shown by Hockett and coworkers46,47 to be 1,4-anhydro-D-mannitol dibenzoate (30), l,4 3,6-dianhydro-D-man-nitol dibenzoate (31), and 2,5-anhydro-l,6-di-0-benzoyl-D-glucitol (32). The latter compound, which can be readily isolated from the... 

Irradiation of unprotected carbohydrates was the subject of greatest photochemical interest to the early carbohydrate photochemists.1 The investigations of these early workers were concerned primarily with the effect of reaction conditions upon the photochemical process, rather than with the identity of the reaction products. Between 1960 and 1969, a comprehensive series of papers was published on the photochemical reactions of D-glucose and D-glucitol.95-99 These studies contributed greatly to understanding of the photochemistry of unprotected carbohydrates, as not only was the result of variation in the reaction conditions studied but also the structures of the products were determined. 

The structure considered to be 2,3 4,5-di-O-methylene-D-glucitol could also be 2,4 3,5-di-0-methylene-D-glucitol. Haworth and Wiggins79 did not determine which of these structures the methyl L-gulonate derivative actually possesses. 

In connection with the structure of glycoproteins, Lloyd and Kabat studied the separation of six alditol acetates,452 and Kim and coworkers57 examined the separation of L-fucitol, D-glucitol, D-manni-tol, and galactitol. Alditol acetates have been used in studies on... 

Oxepane (seven-membered) rings (1,6-anhydrohexitols)52 have been prepared from the 3,4-isopropylidene acetals of D-mannitol, D-glucitol, and L-iditol, by way of alkaline hydrolysis of the corresponding 1,2 5,6-dianhydrides. The ring structures of the products were established through periodate oxidation and lead tetraacetate oxidation the requisite amount of formic acid was produced, and 3 equivalents of lead tetraacetate were consumed. No inversions at any of the asymmetric centers were involved in the reactions conducted, so the oxepanes had retained the configurations of the starting hexitols. 

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. 

Jackson and Hayward59hydroxyl group in l,4 3,6-dianhydro-D-glucitol is preferentially sulfonylated prior to conversion into the mixed ester is incorrect. They based their conclusions on studies of the rate of replacement of p-tolylsulfonyloxy group by iodide in the three dianhydro stereoisomers. However, their proof of structure was questioned by Lemieux and Mclnnes59acetoxonium intermediate prior to attack by the iodide ion. 

The crystal and molecular structures of l,4 3,6-dianhydro-2-0-(p-bromophenylsulfonyl)-(exo)-D-glucitol 5-nitrate(endo) were reported by Camerman, Camerman, and Trotter.69 The bond distances and valency angles were found to be normal, with an intramolecular apparent attraction between an oxygen atom of the N02 and the ring-oxygen atom of the second ring the distance was found to be 0.29 nm. 

The competitive inhibition of aldolase by a number of structural analogs of D-ftuctose 1,6-diphosphate has been investigated.120 Among these analogs were 1,4-anhydro-DL-ribitol 5-phosphate, 1,4-anhydro-DL-xylitol 5-phosphate, 1,4-anhydro-D-arabinitol 5-phosphate, 2,5-anhydro-D-mannitol 1,6-diphosphate, and 2,5-anhydro-D-glucitol 1,6-diphosphate. Their respective, enzyme-inhibitor,... 

Maltitol (4-O-CC-D-glucopyranosyl-D-glucitol) formed by catalytic hydrogenation of maltose (97), has been obtained both as a noncrystalline powder and a viscous liquid (98). Structures of disaccharide alcohols are shown in Figure 3. 

D-Glucitol hexanitrate256 and the pentanitrates of xylitol,257 ribitol,257 and L-arabinitol257 have been partially denitrated by the action of pyridine, but the structures of the reaction products were not ascertained. The dinitrates of the 1,4.3,6-dianhydro derivatives of D-mannitol, D-glucitol, and L-iditol react only slowly in anhydrous pyridine,258 and only traces of mononitrates could be detected in aqueous pyridine, mononitrates accounted for a maximum of 10% of the decomposed dinitrates. 

This reaction was extended to 0-(o-nitrobenzylidene) derivatives of glycerol,67 D-mannitol,68 and D-glucitol.69 Some regioselectivity seems to have been observed, as two acetal groups [of the three for the tri-O-(o-nitrobenzylidene) derivatives of D-mannitol and D-glucitol] were found to have reacted. The identity and the structure of the photo-... 

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