A-glucosamine

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. ... 

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. 

Die Umsetzung des Tetra-O-acetyl-a-glucosamin-hydrobromids (I) mit Silbercyanat oder mit Phenylisocyanat verlauft anders als mit Thiocyanat es findet in normaler Art Harnstoffbildung statt [I->XIV I —> XV das / -Anomere von XIV ist bereits friiher [29) erhalten worden]. 

This enzyme [EC 2.3.1.3] catalyzes the reaction of acetyl-CoA with A-glucosamine to yield coenzyme A and N-acetyl-A-glucosamine. 

B. Pluvinage, M. G. Ghinet, R. Brzezinski, A. D. Boraston, and K. A. Stubbs, Inhibition of the exo-p-D-glucosaminidase CsxA by a glucosamine-configured castanospermine and an amino-australine analogue, Org. Biomol. Chem., 7 (2009) 41694-172. 

The answer is d. (Hardman, pp 1242-1243.) Streptozocin is an alkylating agent with the capacity to cross-link DNA, thereby inhibiting its synthesis. It is a nitrosourea-like antibiotic that contains a glucosamine moiety that allows it to be selectively taken up by the p cells of the islets of Langerhans. Consequently, it can be useful in treating metastatic islet cell carcinoma. 

In model reactions employing a glucosamine-derived anomeric phosphate, we found that we were able to monitor the appearance of the phosphoroimidazolidate intermediate by mass spectrometry. Similarly, we were able to monitor its disappearance upon slow addition of a famesyl monophosphate salt added via syringe. 

An important advantage of the //-phosphonatc method is that at no stage of the synthetic route, is a labile phosphotriester prepared.1036 1041 1 8 The reaction of salicylchlorophosphite (Scheme 3.19) with a glucosamine derivative furnished a phosphite triester which was subsequently hydrolysed to the //-phosphonate monoester. The latter compound was coupled... 

Guggi, D., N. Langoth, M. H. Hoffer, M. Wirth and A. Bernkop-Schnurch (2004). Comparative evaluation of cytotoxicity of a glucosamine-TBA conjugate and a chitosan-TBA conjugate. Int J Pharm 278(2) 353-360. 

ACGLUA11. N-Acetyl-a-glucosamine (CgH NOg). Mo F, Jensen LH (1975) Acta Crystallogr, Sect B 31 2867... 

One of the most characteristic differences between papain and the other sulfhydryl proteases, ficin and bromelain, is the absence of carbohydrate in papain. Glycopeptides have been isolated from ficin (48) and bromelain (49, 50, 51, 52). In the case of bromelain the carbohydrate moiety composed of mannose, xylose, fucose, and N-acetylglucosamine is covalently linked to an asparagine residue of the peptide chain through a glucosamine component of the sugar moiety (51,52). 

Mucopolysaccharidosis lllC Acetyl-CoA a-glucosamine HS Coarse hair, CNS involvement, aggressive behaviour. 

Asthma has reportedly been exacerbated by the use of a glucosamine-chondroitin supplement for osteoarthritis (28). 

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