D-Glucopyranose derivatives

Similarly, various a-D-glucopyranose derivatives having a mesyloxy group at C-4 and an acetoxyl group at C-l are also converted into 1,4-anhydro-/3-D-galactopyranose derivatives on treatment with sodium azide in such aprotic solvents as N,N-dimethylformamide.51 The use of sodium azide in N,N-dimethylformam ide under forcing conditions originated in attempts at nucleophilic displacements to form azido,... 

An approach to 2-deoxy-2-(thiocyanato)-D-glucopyranose derivatives has been reported by Igarashi and Honma.37 This reaction proceeds in the presence of acetic acid and acetic anhydride by addition of thiocyanogen to 3,4,6-tri-O-acetyl-D-glucal (20), with the formation of a mixture of isomeric thiocyanates (274 and 275) and isothiocyanate 21 (3% yield), as well as 3,4,6-tri-0-acetyl-2-(thiocyanato)-D-glucal (276). 

D. Tailler, J. C. Jacquinet, A. M. Noirot, and J. M. Beau, An expeditious and stereocontrolled preparation of 2-azido-2-deoxy-P-D-glucopyranose derivatives from D-glucal, J. Chem. Soc. Perkin Trans. /(1992) 3163-3164. 

H. Kamitakahara, F. Nakatsubo, and K. Murakami, Syntheses of 1,4-anhydro-u-D-glucopyranose derivatives having acyl groups, Mokuzai Gakkaishi, 40 (1994) 302-307. 

H. Kamitakahara and F. Nakatsubo, Substituent effect on ring-opening polymerization of regioselectively acylated 1,4-anhydro-a-D-glucopyranose derivatives, Macromolecules, 29 (1996) 1119-1122. 

In wKich a-D-glucopyranose derivatives are sweeter or produce larger taste responses than B-D-glucopyranose derivatives. (2) The requirement of equatorial hydroxyls at C-2 and C-4 of the D-glucopyranoside molecule for a maximum stimulation in the gerbil parallels a similar requirement for increased sweet taste in man (33.) and maximum stimulation in the sugar receptors of the gly (31). (3) The residues at the... 

FIGURE 2.36 The a,p-anomeric ratio of some D-glucopyranose derivatives. 

Eby, R, Schuerch, C, The use of 1-O-tosyl-D-glucopyranose derivatives in a-D-glucoside s)mthesis,... 

Selected reactions with C-l j -toluenesulfonates can be seen in Tables III and IV. In the series of 2,3,4-tri-Oj-benzyl-l-Q-g-tolylsulfonyl-D-glucopyranose derivatives, a few examples of the influence of C-6 substituent, solvent, and structure of reacting alcohol can be seen (Table III, no. 1-5). The S.-pheny 1 carbamate derivative (no. 5) has been used in a stepwise hexasaccharide synthesis (30), and has been used to prepare -aminophenylethyl glucotetraopyranosides for coupling to proteins (31). The stereoselectivity was equally good in the higher members of the series. 

The octaacetates of /3-isomaltose, /8-maltose, /3-nigerose, and a-koji-biose were obtained in 80, 55.8, 67, and 64% yields, respectively, by reaction of 50b with the appropriately protected D-glucopyranose derivatives in the presence of silver perchlorate and s-collidine, followed by hydrogenolysis and acetylation. /3-Isomaltose octaacetate was also obtained in 79.4% yield by the reaction of 50b with 1,2,3,4-... 

The broad-spectrum antibiotic sptreptozotocin 98 is a 2-deoxy-2-ureido-D-glucopyranose derivative and, consequently, afforded the furo[2,3-d]-imidazol-6-yl acyclo C-nucleoside 99 when treated with sulfamic acid or with hydrogen and palladium (67JA4808 76JAN1218 79JOC9) (Scheme 30). 

Correlations for Certain Aldopyranose Derivatives. In the range 960 to 730 cm Barker et al. (I954a,b,c) have found bands eharacteristie of several aldopyranoses and their derivatives. They identified (1954a), for D-glucopyranose derivatives, three principal sets of bands, which are presented in Table 6.2. These were as follows for a anomers, type la at 917 13 cm type 2a at 844 8 cm" and type 3a at 766 10 cm" and for P anomers, type lb at 920 5 cm" S type 2b at 891 7 cm" and type 3b at 774 9 cm" ... 

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