Alditol oligosaccharides

Tostevin, J. E., "The Hydrodynamic Properties of the Alditol Oligosaccharides," Ph.D. Dissertation, The Institute of Paper Chemistry, 1966. 

D.3 Glycoprotein Constituents (Carbohydrates, Alditols, Oligosaccharides, Mucopolysaccharides, Sialic Acid)... 

The phospht lation of alditols, oligosaccharides, and glycoproteins by use of sodium phosphate in anhydrous media has been described, and a papct on the direct esterification of a dialkyl phoqthate with organic halides in the presence of silver oxide included a number of carbohydrate examples, such as the formation of peracetylated -D-galactosyl phosphate from a-acetobromogalactose. Chl(MO-W, -diisopropylaminoalkoxyphoq)hines [ROP(Cl)N(i-Pr)2J in P3mdine... 

Treatment of the known deoxymannojirimycin derivative 34 (Vol. 23, p. 180, ref. 25) with 2,3,4,6-tetra-O-benzoyl-D-glucopyranosyl chloride or -mannopyranosyl chloride led to derivatives 35. ° See also Chapters 3 and 4 for related imino-alditol glycosides and imino-alditol oligosaccharides, respectively. 

Reduction. Mono- and oligosaccharides can be reduced to polyols (polyhydroxy alcohols) termed alditols (glycitols) (1) (see Sugar alcohols). Common examples of compounds in this class ate D-glucitol (sorbitol) [50-70-4] made by reduction of D-glucose and xyhtol [87-99-0] made from D-xylose. Glycerol [56-87-5] is also an alditol. Reduction of D-fmctose produces a mixture of D-glucitol and D-mannitol [69-65-8],... 

Many bacterial polysaccharides contain phosphoric ester groups. There is a limited number of examples of monoesters. More common are phosphoric diesters, connecting an amino alcohol or an alditol to the polysaccharide chain. Another possibility is that oligosaccharide or oligosaccharide-alditol repeating units are connected to a polymer by phosphoric diester linkages. In addition to the intracellular teichoic acids, several bacteria, for example, different types of Streptococcus pneumoniae, elaborate extracellular polymers of this type. These polymers are generally discussed in connection with the bacterial polysaccharides. 

In a study completed during the early development of f.a.b.-m.s., both f.d. and f.a.b. were used to characterize 101 fractions containing neutral oligosaccharides isolated from human milk. Samples were examined as their peracetylated alditols. In subsequent work, the structures of two minor acidic oligosaccharides from human milk were investigated. The per-methylated derivatives were analyzed by f.a.b.-m.s., and their compositions and sequences were defined by the f.a.b. data. Methylation analysis and partial formolysis were the other principal methods used. 

Oligosaccharides were isolated from PMII by weak acid hydrolysis and separation by SEC and HPAEC-PAD. The isolated oligosaccharides were desalted, reduced and methylated. GC-MS analysis of the partially methylated alditol acetates has been used to reveal the structure of the oligosaccharides. 

PA-1 was partially hydrolyzed with O.IM TFA (40°C, 24 h) and the three fractions (PA-l-I, PA-l-II and PA-l-III) were obtained by Bio-gel P-6. Especially, about 50% of TBA-positive material (PA-l-III) was eluted in the fraction of small oligosaccharide. Permethylated oligosaccharide-alditols from PA-l-III were analyzed by GC-EIMS, and three disaccharide-alditols (IP, 2P and 3P) were detected. EI-MS and component sugar analysis suggested that the major peak, IP was Rha-(l- 5)-Kdo-ol and the minor peaks, 2P and 3P were two epimers of Araf-( l->5)-Dha. 

Figure 2 (A) Effect of lithium-degradation on anti-complementary activity of PG-lc (B) Anti-complementary activity of oligosaccharide-alditols obtained from PG-lc by lithium degradation...

Figure 3 Mitogenic activity of products and oligosaccharide-alditols from PG-lc by lithium degradation...

The oligosaccharide-alditols in PG-lc-4 were analyzed by GC-MS as permethylated oligosaccharide-alditols. The results indicated that PG-lc-4 contained di- to tetrasaccharide-alditols possessing glycosyl units such as Hex-(l- 4)-6-deoxyHex-ol, Pen->Pen->deoxyHex-ol, Pen- Hex->deoxyHex-ol, Hex->Hex- Hex-ol,... 

Alkaline conditions are used so frequently in carbohydrate separations on CarboPac columns that it should be pointed out that acidic conditions are suitable for separation of acidic sugars. Figure 24 shows the separation of sialic acid containing oligosaccharides.256 Alkaline conditions were used for neutral milk oligosaccharides and mucin oligosaccharide alditols were characterized similarly.257 The carbohydrates released from yeast mannopro-tein with N-acetyl-P-D-glucosaminidase were also fractionated on CarboPac ... 

Reddy, G. P. and Bush, C. A., High-performance anion exchange chromatography of neutral milk oligosaccharides and oligosaccharide alditols derived from mucin glycoprotein, Anal. Biochem., 198, 278, 1991. 

Methylation analysis Permethylation of intact oligosaccharides Hydrolysis of glycosidic linkages Reduction to monosaccharide alditols Acetylation of free hydroxyl groups previously involved in link-... 

---