D-melibiose

Aoyama has also shown that 5-indolylboronic acid (3) imdergoes fluorescence quenching upon complexation with oligosaccharides [38]. The stability constants of monosaccharides followed the trend observed by Lorand and Edwards [12] however, higher oligomers of saccharides enjoyed increased stabilization relative to lower oligomers due to a secondary interaction with the indole N-H. The observed stability constants (fC pp) for 3 were D-fructose 630 M", D-glucose 7.1 M" and D-melibiose 58 in water at pH 9. 

D-melibiose 339 M , while the monoboronic acid 28a has a binding constant of 96 in 52.1 wt% methanol-water at pH 8.21 (phosphate buffer). The selectivity of 27a-f for D-melibiose mirrors that for D-glucose, indicating that these diboronic acid sensors form stable 1 1 cyclic structures with the furanose segment of D-melibiose [84]. These observations and those of Hall with polysaccharides complement the observations made by Norrild for monosaccharides [13,14,85]. 

Rigidification of 40 by disaccharide binding increases the stilbene fluorescence. In particular, the disaccharide D-melibiose shows higher selectivity for 40 than other common disaccharides. 

Tewari YB, Goldberg RN (1991) Thermodynamics of hydrolysis of disacchrides lactulose, a-D-melibiose, palatinose, D-trehalose, D-turanose and 3-o- -D-galactopyranosyl-D-arabinose. Biophys Chem 40 59-67... 

It was found98 that the amount of sucrose consumed could be accounted for entirely as levan and reducing sugars. Fructose formed part of the reducing sugars produced, and there was no appreciable interconversion of aldose and ketose. When raffinose was used as substrate, the products were levan, melibiose and D-fructose (but not sucrose and D-galactose). The following equation expresses fully the net result of the action of the autolyzate ... 

The rate of oxidation of ethylene glycol was found268-269 to attain a broad maximum between pH 2.5 and 6. In a very complete study of the effect of pH on the periodate oxidation of carbohydrates, Neumiiller and Vasseur260 showed that the oxidation of maltose, melibiose, methyl a-D-... 

Melibiosone was prepared by the action of benzaldehyde on melibiose phenylosazone17-191 and was identified by conversion into melibiose p-bro-mophenylosazone. On treatment with emulsin, it was hydrolyzed to D-glucosone and D-galactose.17,203... 

The naturally-occurring 1,6-linked glucose polymers furnish other sources of 2,3,4-trimethyl-D-glucose, which has been isolated from the hydrolysis products of the methyl ethers of gentiobiose,112 118 melibiose,114 raffmose106 116 and dextran.78 74,116... 

C HgaOn-HaO 6-0-a-D-Galactopyranosyl-a,/3-D-glucopyranose monohydrate Q ,/3-melibiose monohydrate (MELIBM10)71... 

This enzyme [EC 3.2.1.22] catalyzes the hydrolysis of melibiose to yield galactose and glucose. It will also act on terminal, nonreducing a-D-galactose residues in a-D-galactosides. In addition, it will hydrolyze a-D-fucosides. 

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