Glucosamin

Supplement 1942 195-449 Hydroxy-amines Aminoethyl alcohol, 274. Carbonyl-amines Aminoacetaldehyde, 307. Aminoacetone, 314. Hydroxy-carbonyl amines Glucosamine, 328. Aminocarboxylic acids Glycine, 333. Hydroxylamines, 534. Hydrazines, 546. Azo Compounds. 562. Oryano-metallic Compounds, 580. 

Another structural variation is the replacement of a hydroxyl group m a carbohydrate by an ammo group to give an ammo sugar The most abundant ammo sugar is one of the oldest and most abundant organic compounds on earth N Acetyl d glucosamine is the... 

Fig. 3. The stmcture of the nodulation (Nod) factors of i bium meliloti 2011 (44), where is 2 or 3, R is —H or—COCH, and R is C 2 as shown, C gT, or ie, a fatty acid chain having from 1 to 3 double bonds. The A/-acetyl glucosamine residues and an acyl moiety, R, are present ia all...

A M A D 0 R I Glucosamine Rearrangement Conversion of N-glucosxfes of aldoses to N-glucosides of ketoses... 

Dibenzyl phosphoramidates have been prepared from amino acids and the j)hos-phoryl chloride, (Bn0)2P(0)Cl. ° A diphenyl phosphoramidate has been prepared from a glucosamine it is converted by transesterification into a dibenzyl derivative to facilitate cleavage. ... 

To 40 g. of dry chitin in a 500-ml. beaker is added 200 ml. of concentrated hydrochloric acid (c.p., sp. gr. 1.18), and the mixture is heated on a boiling water bath for 2.5 hours with continuous mechanical agitation. At the end of this time solution is complete, and 200 ml. of water and 4 g. of Norite are added. The beaker is transferred to a hot plate, and the solution is maintained at a temperature of about 60° and is stirred continuously during the process of decolorization. After an hour the solution is filtered through a layer of a filter aid such as Filter-Cel. The filtrate is usually a pale straw color however, if an excessive color persists, the decolorization may be repeated until the solution becomes almost colorless. The filtrate is concentrated under diminished pressure at 50° until the volume of the solution is 10-15 ml. The white crystals of glucosamine hydrochloride are... 

The preparation of glucosamine hydrochloride from lobster shells and crab shells by essentially this method has been reported by Irvine, McNicoll, and Hynd and Hudson and Dale. Other methods involving the use of cicad larvae shells and shrimp shells ls also have been reported. 

The next major bonded phase project was the development of the GBR resin, which stands for modified glucose bonded on both the backbone and the ring of basic PDVB gels. The manufacture of this product was ultimately achieved, as outlined later. The gel is first brominated, which places bromine atoms on both tertiary hydrogens of the PDVB. The brominated gel is then reacted with chlorosulfonic acid, and a specially treated reduced D-glucosamine is coupled to the gel. This process has the potential to covalently bond up to three sugar residues to each available divinylbenzene residue in the PDVB polymer. The exact reaction conditions used are proprietary however, the surface of the finished product is believed to look similar to Figs. 13.11 and 13.12. 

FIGURE 9.20 The glycosyl phosphatidylinositol (GPI) moiety is an elaborate lipidanchoring group. Note the core of three mannose residues and a glucosamine. Additional modifications may include fatty acids at the inositol and glycerol —OH groups. 

Na2S204, NaOH. This method was used for deprotection of a glucosamine. Cleavage occurs by reduction to the amine, which then undergoes a 1,6-elimination. 

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