Glucitol ethers, separation

Certain synthetic heptitols that could not be separated by paper chromatography or by electrophoresis have been separated as their O-trimethylsilyl derivatives.404 The procedure of reductive, alkaline hydrolysis, much used in glycopeptide research, yields alditols that have been estimated as their trimethylsilyl ethers,59,405 and D-glucitol in mammalian nerve has similarly been determined.406... 

The separation of the mediyl ethers of glucose as their acetylated methyl glycosides and as their acetylated glucitols has been studied by H. G. Jones and J. K. N. Jones, " and the behavior of a series of methylated methyl glucosides was reported by Heyns and coworkers the results were used in connection with a mass-spectrometric study. 

The resolution of methyl ethers of D-glucitol as their acetates, trifluoro-acetates, or trimethylsilyl derivatives was examined. For the last compounds, it was found that 2,6- and 3,6-dimethyl ethers are only partly separated, and that the 2- and 3-monomethyl ethers are not separated at all. This result accords with the observation that trimethylsilyl ethers of alditols are often poorly resolved. 

Acetonation of 3-0-methyl-D-glucitol affords the isomeric 1,2 5,6-and 2,4 5,6-di-0-isopropylidene derivatives which are differentiated on silica gel layers [hRf 50 and 25, respectively, in benzene-methanol (90 + 10)] with visualization by iodine vapor [85]. The four stereoisomers of l,2 5,6-di-0-trichloroethyUidene-a-D-glucofuranose, which differ in the configuration of the acetal carbons atoms, are resolved on silica gel with ethyl acetate-petroleum ether (b. p. 40—50°) (50 + 50) [86]. Chloroform-acetone (97 + 3) and benzene-ether (90 + 10) have been used to separate mixtures of acylated di-O-isopropylidene-hexitols [87, 88]. 

Xylitol and o-glucitol have been measured using o-glucitol dehydrogenase. Mixtures of polyhydroxy compounds have been separated as their tungstate complexes. Polyol profiles in cerebrospinal fluid have been measured by g.l.c. of the TMS ethers. ... 

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