Definitions disaccharides

Classification Disaccharide Definition Commercial prod, is the monohydrate Empirical C12H22O11 Formula C6H70(0H)40C6H70(0H)4 Properties Wh. hard cryst. mass orwh. powd., odorless to si. char, odor but readily absorbs odors, mildly sweet taste, odorless sol. in water, alcohol, ether si. sol. in alcohol m.w. 342.34 dens. 1.525 (20 C) m.p. 203.5 C (dec.) b.p. 

Laclosum Milk sugar Sacchamm lactin Saccharum lactis ClassiTication Disaccharide Definition Commercial prod, is the monohydrate Empirical CjjHjjO,... 

Several disaccharides containing one residue of an amino sugar have been synthesized by definitive chemical methods in connection with the study of the oligosaccharides from human milk. Others have only been prepared, as noted, by degradation of natural oligosaccharides. 

Fig. 16.—Schematic representation of a disaccharide residue of amylose showing the definition of the virtual bond (broken lines). [Reproduced with permission from Fig. 4 of P. Dais, Carbohydr. Res., 160 (1987) 73-93 and Elsevier Science B.V.]...

In the eight disaccharide hydrates, six water molecules are four-coordinated and three are three-coordinated. In the four trisaccharide hydrates, the ratio is reversed with eight three-coordinated and three four-coordinated. This suggests that the more complex the molecules, the greater trend toward three-coordination, but the sampling is too small for a definitive conclusion. 

Jorpes " associated activity with degree of sulfation (see page 361), and he reported that his amorphous preparations had a sulfur content of 13.5 % (sodium salt basis). The fractionation procedures (brucine salt) were performed on heparins obtained from various tissues, " and it was postulated that the heparin material was not a definite compound but was a mixture of mucoitin polysulfuric acid esters. Fractions corresponding in their sulfur content to mono-, di-, and tri-sulfates (per disaccharide period) were obtained, together with sulfur-free fractions (see also Marbet and Winter-stein ). The most active material had a sulfur content of 13.8%, corresponding to three sulfate groups per disaccharide unit. 

Branching. It is hoped that branching can be definitely established by purely chemical means, and that the type of linkage can be identified by isolation of the disaccharide involved. 

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