D-glucosamine

D-Glucosamine is phosphorylated by a hexokinase preparation from yeast. The resulting phosphorylated derivative consumes four moles of periodate per mole and is, therefore, considered to be D-glucosamine 6-phosphate. 

The rate of D-glucosamine phosphorylation is about 70% of that for D-glucose phosphorylation. Free D-glucosamine and adenosine-5-tri-phosphoric acid disappear at similar rates in the presence of yeast hexokinase.  

Although W-acetyl-D-glucosamine has inhibitory properties, it is apparently not phosphorylated. When AT-acetyl-D-glucosamine is added alone to ox-brain extracts, no carbon dioxide is produced. Yeast hexokinase 

D-Glucosamine 6-phosphate is hydrolyzed by the D-glucose-6-phosphatase of rat-liver mitochondria. The rate of this hydrolysis is about 8 % of that of D-glucose 6-phosphate hydrolysis. A phosphatase which preferentially catalyzes the hydrolysis of D-glucosamine 6-phosphate has been prepared from Neurospora crassa. This enzyme is not stimulated by magnesium ions and has an optimum activity between pH 6 and 7.5. It appears to be distinct from acid, alkaline, and other specific phosphatases. 

With the purified enzyme, the phosphoglucomutase reaction is several hundred times faster than the phospho-D-glucosamine mutase reaction.  

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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... 

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. 

Recently, Li et al. [30], Yu et al. [31] reinvestigated the mechanism of graft copolymerization of vinyl monomers onto carbohydrates such as starch and cellulose initiated by the Ce(IV) ion with some new results as mentioned in Section II. Furthermore, they investigated the mechanism of model graft copolymerization of vinyl monomers onto chitosan [51]. They chose the compounds containing adjacent hydroxyl-amine structures, such as D-glucosamine, /mn5-2-amino-cyclohexanol, 2-... 

There has been one report on the biosynthesis of FR900482 [114]. Radiolabeled D-glucosamine 33 and AHBA 38 were efficiently incorporated into 6, and D-[l-13C]-glucosamine was incorporated in the expected orientation (Figure 11.10). The biosynthetic gene cluster for FR900482 has been isolated from Streptomyces sandaensis and indicates a strong biosynthetic relationship with mitomycin C (Y. Mao, D. H. Sherman, unpublished results). 

Henry reaction of the (V-acetyl-D-glucosamine derived nitrosugar 1 with 2,3-O-cyclohexylidene-D-glyceraldehyde (2) furnishes a single product 3 in 85-90% yield7. 

Analog erhalt man aus N-Benzoyl-D-glucosamin-uronsaure 5-Benzoylamino-5-des-oxy-i-gulonolacton (70% d.Th. F 222-232° Zers.). 

Amino-sugars and Related Compounds. Part I. The Deamination of D-Glucosamine Hydrochloride, B. C. Bera, A. B. Foster, andM. Stacey,/. Chem. Soc., (1956) 4531-4535. 

Observations on the Acidic Hydrolysis of Some D-Glucosamine Derivatives," A. B. Foster, D. Horton, and M. Stacey, Chem. Ind. (London)., (1956) 175-176. 

Reactions of 2-(2, 4 -Dinitrophenyl)-amino-2-deoxy-r>-glucose, (DNP-D-glucosamine), and derivatives, P. F. Lloyd and M. Stacey, Tetrahedron, 9 (1960) 116-124. 

Amino-2-deoxy-a-D-glucose (a-D-Glucosamine) from Crustacean Shell, M. Stacey and J. M. Webber, Methods Carbohydr. Chem., 1 (1962) 228-230. 

Lactosediamine (LacdiN) 2-Amino-2-deoxy-P-D-galactopyranosyl-(1 -44)-D-glucosamine... 

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