Glucopyranoside phenyl

Key + = hydrolyzed — = not hydrolyzed = slow hydrolysis. 6 Methyl a-D-glucopyranoside. c p-Nitrophenyl a-D-glucopyranoside. Phenyl a-D-glucopyranoside. 

It was of interest to determine whether glycosides of 6-deoxy-D-xylo-hex-5-enopyranose were susceptible to enzyme hydrolysis by / -glucosi-dase. Since aromatic glucosides are hydrolyzed by this enzyme at a much faster rate than aliphatic glycosides, phenyl 6-deoxy-/ -D-rt/Zo-hex-5-enopyranoside (18) was prepared (20). Phenyl / -D-glucopyranoside was converted to the 6-tosylate by selective esterification and then, by conventional procedures, transformed to phenyl 2,3,4-tri-0-acetyl-6-deoxy-... 

Phenyl tetra-O-acetyl-a-D-glucopyranosyl sulfoxide or phenyl 2,3,4,6-tetra-Oacetyl-1-thio-a-D-glucopyranoside S-oxide... 

Neohesperidin dihydrochalcone 2-O-a-L-rhamnosyl- -D-glucopyranoside substituted phloroglucinol, -QH, substituted phloroglucinol, -C2H4 phenyl OH and —OMe... 

Reaction of ally I tetraacetyl P-D-glucopyranoside and phenyl boronic... 

Only a few reactions with bidentate ligands have been described. 32, reacting with the chiral carbohydrate derivative phenyl-4,6-o-(R)-benzylidene -2,3, 0-bis(diphenyl-phosphino-/ -D-glucopyranoside) (Ph-/ -glup), gave the compound [TcBr(CO)3 (Ph-/Tglup)] (56) in 53% yield. The complex was characterized by elemental analysis and i.r. spectroscopy [71]. Furthermore, reaction with dithio-... 

Decomposition of salicin (2-(hydroxymethyl)phenyl-/ -D-glucopyranoside) yields two alcohols glucose (a compound with numerous 1°, 2°, and a 3° hydroxyl functionalities, Fig. 13.4.6) and l-0H-2-CH20H-benzene (a 1° alcohol, Fig. 13.4.7). Further oxidation of l-0H-2-CH20H-benzene leads to the formation of salicylic acid ... 

Lack of selectivity in the reaction of the /3-D-glucoside derivative with one molar equivalent of benzylthiocarbonyl chloride has also been noted 40% of the 2,3-diester and 40% of the starting material were isolated.40 Similarly, unimolar benzoylation of phenyl 4,6-0-benzylidene-/3-D-glucopyranoside gave only 9% of the 3-ester, together with 47% of the 2,3-diester.41 Acylation of benzyl 4,6-0-benzylidene-/8-D-glucopyranoside with acetic anhydride-pyridine-pyridine hydrochloride yielded,42 in contrast to the reaction with the... 

Phenyl l-thio-0-D-glucopyranoside tetraacetate to 1,5-anhydro-D-glucitol... 

The effect on /3-glucosidase activity of substitution in the glucon has been carefully investigated by the school of Helferich. It has been established that substitution of the hydroxyl groups at C2, C3 and C4 renders the /3-D-glucopyranoside unhydrolyzable (i.e., E.V. less than 10 s) by almond emulsin. This refers to phenyl 3-methyl-/3-D-gluco-pyranoside,29 phenyl 2,4,6-trimethyl-/3-D-glucopyranoside89 and to the... 

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). 

Carbohydrates remain an attractive source of chirality in preparation of ligands for asymmetric catalysis. Functionalized phospholanes, 192 [167], and chiral bisphosphinites 193 [168] with an attached crown ether unit were obtained recently from D-mannitol and from phenyl 2,3-di-0-allyl-4,6-0-benzylidene-p-D-glucopyranoside, respectively (Figure 18). Compounds 194 and 195 were obtained in the photochemical addition of H2P(CH2)3PPH2 onto the crresponding alkenes - Pd-complexes of these new bisphosphines were successfully applied as catalysts in the copolymerization of CO and... 

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