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Methyl a- and -D-glucopyranoside

Reeder and Eckstedt389 studied the interaction of con A with teichoic acids from Staphylococcus aureus and Staphylococcus epidermidis by gel diffusion, and precipitation in a fluid system. The teichoic acid from strain Tj of S. epidermidis contains a-D-glucopyranosyl residues, and it precipitated with con A, whereas strain T2, which is /3-D-glucosylated, did not. Classical precipitin curves resulted when con A interacted with strains T2 and 412 (also a-D-glucosylated) the precipitation was specifically inhibited by D-glucose, 2-acetamido-2-deoxy-D-glucose, and methyl a- and /3-D-glucopyranosides.389... [Pg.176]

Step 7 Proton transfer from the positively charged ring oxygen to the oxygen of methanol giving a mixture of methyl a- and (3-D-glucopyranoside. The acid catalyst is regenerated in this step. [Pg.1045]

Methyl a-D-glucopyranoside may be converted,271 in a remarkably selective reaction, into its 2,4,6-tribenzyl ether (in 62% yield) on treatment with three molar equivalents of sodium hydride in benzyl chloride at 110°, a substitution pattern that might have been predicted in view of the low, relative reactivity of HO-3 towards alkylation in the mechanistically related, Haworth procedure.268 Similar, selective benzylations have also been achieved on partially substituted derivatives of methyl a- and /3-D-galactopyranoside272 and on methyl 6-deoxy-a-L-galactopyranoside62 in all of these, an unexpectedly high relative-reactivity of HO-4 (ax) compared to that of HO-3 (eq) was noted, indicating that steric factors are not the sole influence on reactivity in these cases. Nevertheless, the primary hydroxyl... [Pg.57]

Thus, irradiation of phenyl /3-D-glucopyranoside yielded D-glucose (up to 70% yield) the conversion of the same glucoside into methyl a- and jS-D-glucopyranoside (transglycosylation) may also serve as an example to illustrate the reaction mechanism (see Scheme 6). [Pg.184]

Although hydrazine hydrate in ethanol is effective in achieving denitration of carbohydrate nitrates,243,244 the reagent showed little selectivity in its reactions244 with the 2,3-dinitrates of methyl 4,6-O-ben-zylidene-a- and methyl 4,6-0-ethylidene-a- and -/3-D-glucopyranoside. [Pg.58]

Such compounds have been identified amongst the products of deamination, followed by reduction, of methyl 2-amino-2-deoxy-a-and -/3-D-glucopyranoside.89a Two methyl 2-deoxy-2-(hydroxy-methyl)pentofuranosides, epimeric at C-2, were detected in each case, and the results of deuterium-incorporation experiments suggested that the primary product was epimerized, probably during reduction with sodium borohydride. However, in the writer s opinion, the configurations assigned to the primary and epimerized products are incorrect and should be reversed. [Pg.22]

Studies have revealed that the deamination of 2-amino-2-deoxy-D-glucosides is more complicated than previously supposed. It has been reported that methyl 2-amino-2-deoxy-a- and -/3-d-glucopyranoside give, in addition to 2,5-anhydro-D-mannose, methyl 2-deoxy-2-C-formyl-a- and -/S-D-ribofuranoside (for example, 97 to 98) in yields of 25 and 19%, respectively, under the experi-... [Pg.233]

Figure 1. Methyl a- and ft-D-glucopyranoside, showing orientation (dotted line) of the resultant negative end of ring oxygen dipole (the hydrogens and hydroxyl groups on C-3, -4, and -6 have been omitted for clarity)... Figure 1. Methyl a- and ft-D-glucopyranoside, showing orientation (dotted line) of the resultant negative end of ring oxygen dipole (the hydrogens and hydroxyl groups on C-3, -4, and -6 have been omitted for clarity)...
Schuerch and coworkers140 153 also studied the methanolysis of 6-0-acyl-2,3,4-tri-0-benzyI-a-D-glucopyranosyl halides, and observed the effects of the 6-O-acyl substituent upon the reaction rate and the ratio of methyl a- to /3-D-glucopyranoside. In applying this principle, Lem-ieux and coworkers132 133 prepared oligosaccharides in good yield as mentioned earlier. [Pg.275]


See other pages where Methyl a- and -D-glucopyranoside is mentioned: [Pg.19]    [Pg.57]    [Pg.73]    [Pg.83]    [Pg.255]    [Pg.51]    [Pg.158]    [Pg.163]    [Pg.30]    [Pg.99]    [Pg.269]    [Pg.275]    [Pg.41]    [Pg.19]    [Pg.57]    [Pg.73]    [Pg.83]    [Pg.255]    [Pg.51]    [Pg.158]    [Pg.163]    [Pg.30]    [Pg.99]    [Pg.269]    [Pg.275]    [Pg.41]    [Pg.54]    [Pg.98]    [Pg.283]    [Pg.284]    [Pg.185]    [Pg.351]    [Pg.352]    [Pg.82]    [Pg.21]    [Pg.47]    [Pg.73]    [Pg.56]    [Pg.18]    [Pg.25]    [Pg.27]    [Pg.129]    [Pg.201]    [Pg.72]    [Pg.240]    [Pg.358]    [Pg.14]    [Pg.28]    [Pg.246]    [Pg.35]    [Pg.60]    [Pg.61]    [Pg.161]   


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A-D-glucopyranoside

D-Glucopyranoside

D-Glucopyranosides

Glucopyranosid methyl

Glucopyranoside methyl 6-0-

Glucopyranoside methyl-, a- and

Methyl (3 d glucopyranoside

Methyl D-glucopyranosides

Methyl a d glucopyranoside

Methyl a-glucopyranoside

Methyl glucopyranosides

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