Substituted-Phenyl Glycosides

Salicin is a glucoside found in willow bark Salix) and in poplar bark Populus). Particularly in the poplar bark, it is found accompanied by a second glucoside, populin. Salicin is o-hydroxymethylphenyl /3-D-glucoside, 

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The azirine derivative (58), when photolysed in the presence of an immunoglobulin, labelled the galactan-binding area.- - Also in the area of carbohydrate-protein binding, novel descriptors have been used in the analysis of the quantitative structure-activity relationship of the binding of p-substituted phenyl glycosides to concanavalin A. " ... 

In a study of the chiroptical properties of some substituted-phenyl glycosides, it was noted that steric and electronic effects associated with orrAo-substituents may change the sign of some of the c.d. bands of the aromatic chromophore. ... 

The influence of hydrophobic substituents on the inhibition potency of aryl a- and /3-D-gluco- and a-D-manno-pyranosides was also investigated. A linear correlation was demonstrated between the hyd-rophobicity of the substituent and the inhibiting power of the glycoside for o-, m-, and p-substituted-phenyl /3-D-gIucopyranosides.180,181,333,436... 

Phenyl 3- or 4-O-alkyl-R-D-glucopyranosides yield substituted 1,6-anhydro-/3-D-glucopyranoses,32,48-52 whereas 2-O-alkyl derivatives do not react under those conditions.32,33,43,49 The phenyl glycosides of 2-, 3-, or 4-deoxyhexoses behave similarly (see Sect. VII,3). 

Thompson and coworkers investigated the acid hydrolysis of aryl glycosides of /3-n-glucopyranose and d-n-glucopyranuronic acid. They found that the rates of hydrolysis of substituted-phenyl d-u-glucopyranosid-uronic acids show little sensitivity to effects of a polar aglycon group (Ham-... 

Aryl 1-thioglycosides have also been examined for their ease of acid hydrolysis.i Pora-substituted-phenyl 1-thioglycopyranosides of fi-D-glucose, /S-D-galactose, -D-xylose, and a-L-arabinose were hydrolyzed in 3 N hydrochloric acid at 80° the rates are in the order (p-substituents) 0H>0Me>Me>H>Cl>Br>N02. This is the same as the order found for glycosides (see Table XXVI). 

Ac or Bz) at 160—190°C gave, after chromatography, modest yields of methyl or phenyl 2,3,4,6-tetra-0-acetyl(benzoyl)-P-D-glucopyranoside, whereas the a-anomers of (27) were not susceptible to decarboxylation. Fusion of (27 R = Ph, R = Ac) with 2-chloro- or 2-nitro-phenol at 130—140°C provided satisfactory preparations of the substituted-phenyl P-glycosides in yields of 65 % and 95 %, respectively. These reactions proceed by way of 1,2-orthoester intermediates. 

H-(3-Ethylindolyl)-D-xylopyranosylamine, eight H-(substituted-phenyl)pentopyranosylamines, and their M-nitroso-derivatives have been synthesized and their mutagenicities reported. The synthesis and antitumour activity of quaternary ellipticine N-glycosides is covered in Chapter 19, and the e.i.-m.s. fragmentation of per-Q-acetylated H-(4-substituted-phenyl)glycopyranosylamines in Chapter 22. 

E.i.-m.s. data for acetylated 2-ketopyranoses and their glycosides, and for per-Q-acetylated li-(4-substituted phenyl)-D-xylo- and D-gluco-pyranosylamines have been reported,as have both e.i.- and c.i.-m.s. data for the amino-sugar derivatives (1) and (2), The g.c.-m.s. (e.i. and c.i.) of the per-Q-methylated... 

Unsaturated C-glycosides can be made by direct substitutions applied to other 2,3-unsaturated compounds. Thus, phenyl glycosides treated with ethyl nitroacetate, trlphenylphosphine and... 

The preparation of N-phenylcarbamates from incompletely substituted, carbohydrate boronates is, perhaps, the least destructive of esterifying reactions, requiring only that the compounds be heated with phenyl isocyanate in dry benzene or toluene. Several reports have appeared on successful application to glycoside,22,51,58,69 sugar,47 and alditol23 derivatives. 

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