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Sucrose with periodate

No oxidation products of sucrose other than those produced by degradation have been described. Oxidation of sucrose with periodic acid has been carried out, but neither the method nor the products need to be considered for the present purpose. [Pg.297]

Barry and Mitchell were the first to oxidize sucrose with periodic acid, separating the product as a phenylhydrazone. On finding that, after oxidation, each of the two monosaccharides of the sucrose reacted with only one molar proportion of phenyhydrazine, these workers attributed to the oxidized sucrose not a dialdehyde, but the following hemialdal [bis(hemi-acetal) hydrate] structure. [Pg.152]

The ready condensation of sucrose with excess triphenylmethyl chloride in pyridine to a tri-trityl ether is, however, more easily explained by XV or II, which have three, instead of two (c/. I), primary alcohol groups to react selectively in the condensation. Fleury and Courtois oxidized sucrose for twenty-four hours at 14° with an excess of suitably buffered periodic acid and found that three moles of the oxidant were consumed and one mole of formic acid was eliminated. This highly selective oxidant is known to cleave unsubstituted 1,2 glycols quantitatively to two carbonyl groups and to eliminate the center carbon atom... [Pg.16]

Methylated 1,4-dihydropyrazines (1,2,4-tri-, 1,2,4,5-tetra-, and 1,2,4,6-tetramethyl) as well as imidazolines have been isolated from the reaction of sucrose with methylamine at high temperatures (120°-260°), for prolonged reaction periods (18 hours) and in the presence of ammonium phosphate as catalyst. 1,4-Dihydropyrazines are also isolated from the reaction of sucrose and ethanolamine sucrose-ammonia interaction yields a wide range of pyrazines and imidazoles.369-372... [Pg.184]

Oxidation — Apart from C02 and H20, there are three series of products that result from the oxidation of saccharide. They are 2,3-dialdehydes (5.43 and 5.49) formed on the oxidative cleavage of saccharides (5.42 and 5.48) with periodates, the sole oxidants providing such course of oxidation. Such dialdehydes are considered toxic. Further oxidation of dialdehydes leads to glyceric acid (5.45), glyoxalic acid (5.47), hydroxypyruvic acid (5.46), and erythronic acid (5.51), as shown below for the oxidative cleavage of sucrose (5.42) and maltose (5.48). [Pg.93]

Sucrose derivatives with substituents at the primary positions undergo selection oxidation with periodate in the glucose ring, the 6,l, 6 -tri-0-trilyl derivative reacting at the 2,3-diol, and the TBDMS analogue at the 3,4-position. Products of oxidation were... [Pg.29]

Figure 4. Effect of hyperosmolality on lysosomal enzyme release from rabbit neutrophils. Cells were preincubated 10 min at 37 C in either regular HEPES buffer at 320 mosmol/kg ( ) or in HEPES buffer with 0.3-M sucrose at 680 mosmol/kg ( ), 5 Mg/mL cyto-chalasin B was added, cells were stimulated with FMLP, and p-glucuronidase was released into the medium during a 6-min period measured. Figure 4. Effect of hyperosmolality on lysosomal enzyme release from rabbit neutrophils. Cells were preincubated 10 min at 37 C in either regular HEPES buffer at 320 mosmol/kg ( ) or in HEPES buffer with 0.3-M sucrose at 680 mosmol/kg ( ), 5 Mg/mL cyto-chalasin B was added, cells were stimulated with FMLP, and p-glucuronidase was released into the medium during a 6-min period measured.
Bovine growth hormone, a difficult protein for which to develop controlled release systems due to its propensity toward self-aggregation and inactivation, has successfully been incorporated into polyanhydride matrices (18). The growth hormone was colyophilized with sucrose, dry-mixed with finely powdered polyanhydride, and then compression molded into 1.4-cm-diaraeter wafers, 1 mm thick. As is shown in Fig. 15, release of bovine growth hormone was well controlled over a prolonged period of time. The assay for bovine... [Pg.60]


See other pages where Sucrose with periodate is mentioned: [Pg.35]    [Pg.96]    [Pg.24]    [Pg.17]    [Pg.20]    [Pg.306]    [Pg.891]    [Pg.35]    [Pg.930]    [Pg.235]    [Pg.11]    [Pg.83]    [Pg.109]    [Pg.132]    [Pg.213]    [Pg.301]    [Pg.229]    [Pg.96]    [Pg.48]    [Pg.142]    [Pg.488]    [Pg.489]    [Pg.426]    [Pg.105]    [Pg.407]    [Pg.5]    [Pg.23]    [Pg.36]    [Pg.44]    [Pg.296]    [Pg.92]    [Pg.93]    [Pg.91]    [Pg.74]    [Pg.698]    [Pg.719]    [Pg.105]    [Pg.46]    [Pg.10]    [Pg.198]    [Pg.170]    [Pg.44]   
See also in sourсe #XX -- [ Pg.127 ]




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