Benzoyl-D-glucose

In the case of the above mentioned benzoyl-D-glucose derivatives a correlation was found between the formation of D-glucose dibenzamide and the permanent or transitory existence of a free aldehyde group. The same behavior was noted for triacetyl-oZdehydc-L-erythrose (XLI), which by the action of ammonia produces L-erjrthrose diacetamide (XLII). Isbell and Frush have obtained a similar result in the case of tetraacetyl-oWe/it/do-L-arabinose which, when treated with methanolic ammonia, gave L-arabinose diacetamide in 53 % yield. 

Primary alcohol groups in several protected ribo-, fructo- and glucofuranoses including 2,3,4-tri-O-benzoyl-D-glucose, 1,2-isopropylidene-D-xylo-furanose, 2,3 4,5-di-0-isopropylid-ene-D-fructopyranose, methyl 2,3-O-isopropylidene-P-D-ribofuranoside, l,2-0-isopropylidene-3,5-0-benzylidene-D-glucofuranose and... 

The reaction was also studied with acetylated and benzoylated pyranose and furanose derivatives of D-galactose,18 D-mannose,19 D-lyxose,20 L-rhamnose,10 D-ribose, D-xylose, and L-arabinose,21 and with some partially benzoylated D-glucoses.22... 

The presence of alkoxide ion would enhance the rate of ammonolysis, and the formation of bis(amido) derivatives by an ortho-ester mechanism (see Section VI, p. 110) would be partially suppressed in the competitive set of reactions. Thus, ammonolysis of penta-O-benzoyl-D-glucose in the presence of 5 mmolar proportions of sodium meth-oxide showed a decrease of 11% in the yield of the bis(benzamido)-glucitol derivative as compared with the same reaction conducted without added methoxide ion.47... 

Mixed bromides 33, 34 formed from either 1 -0-acetyl-2,3,5,6-tetra-O-benzoyl-/ -D-glucose or -galactose, also undergo preferential endo-elimina-tion on treatment with DBU, and give the alkene (170). As in the pyranose series, exo-elimination is favored with use of zinc - acetic acid, and geometric isomers (171) are the main products and are formed93 together with the 3-deoxy-3-ene (172). 

Borate complexes have been utilized by Brigl and Griiner47 to effect partial esterification. Anhydrous D-glucose and metaboric acid dissolved in acetone give a complex which exhibits the analysis of a diborate. Reaction of the latter with an excess of benzoyl chloride gives 2,6-di-O-benzoyl-D-glucose (XL). D-Mannitol likewise forms a diborate, which produces the 1,6-di-O-benzoyl derivative (XLI) upon benzoylation. In the presence of boric acid, D-glucose diethyl thioacetal yields the 6-benzoate (XLII). In the non-aqueous medium the formation of complexes... 

Tri-O-benzoyl-D-glucose and benzoyl chloride in pyridine give... 

Brigl and Muhlschlegel148 were able to isolate 3,4,5,6-tetra-O-benzoyl-D-glucose diethyl thioacetal from the thioacetal and benzoyl chloride in an aqueous solution of alkali. When the reaction is carried out in pyridine, both the tetra- and the penta-benzoate are obtained. The tetrabenzoate has been described as a convenient intermediate for the synthesis of 2-0-methyl-n-glucose and its derivatives.149 It is somewhat surprising that position 2 should exhibit this resistance to benzoylation, since preferential methylation occurs in this position. A benzoyl migration could possibly explain the anomalous observations. 

Benzochloro-a>D-glucose is obtained in 77% yield by reaction of penta-0-benzoyl-/ -D-glucose with 1 mole of TiCl4 in CHC13 for 4 h at 60°.1015... 

Displacements Catalyzed by Adds.—The acid-catalyzed mercaptala-tion reaction with ethanethiol normally leads to the aldose diethyl dithio-acetal, but, in anhydrous reaction media, further ethylthio substituents may be introduced into the molecule, usually at C-2. Brigl and coworkers found that ethanethiol and hydrogen chloride convert 3,4,5,6-tetra-O-benzoyl-D-glucose diethyl dithioacetal into 3,4,5,6-tetra-O-benz-oyl-2-)S-ethyl-2-thio-D-glucose (mannose) diethyl dithioacetal. The diethyl... 

Tetrabenzoyl 3,4,5,6-Tetra-O-benzoyl-D-glucose diethyl dithioacetal... 

Sugar esters are also found widely in nature. Phosphoric acid esters are important intermediary products of metabolism, while sulfuric acid esters are constituents of some polysaccharides. Examples of organic acid esters are vacciniin in blueberry (6-benzoyl-D-glucose) and the tannintype compound, corilagin (1,3,6-trigalloyl-D-glucose) ... 

P-Benzoyl-D-glucose (Periplanetin) Araiostegia perdurans Copel. C13H16O7 193-195 -22.0 55 ... 

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