4171-72-6Relevant academic research and scientific papers
Why Is Direct Glycosylation with N-Acetylglucosamine Donors Such a Poor Reaction and What Can Be Done about It?
Marqvorsen, Mikkel H. S.,Pedersen, Martin J.,Rasmussen, Michelle R.,Kristensen, Steffan K.,Dahl-Lassen, Rasmus,Jensen, Henrik H.
, p. 143 - 156 (2017/04/26)
The monosaccharide N-acetyl-d-glucosamine (GlcNAc) is an abundant building block in naturally occurring oligosaccharides, but its incorporation by chemical glycosylation is challenging since direct reactions are low yielding. This issue, generally agreed upon to be caused by an intermediate 1,2-oxazoline, is often bypassed by introducing extra synthetic steps to avoid the presence of the NHAc functional group during glycosylation. The present paper describes new fundamental mechanistic insights into the inherent challenges of performing direct glycosylation with GlcNAc. These results show that controlling the balance of oxazoline formation and glycosylation is key to achieving acceptable chemical yields. By applying this line of reasoning to direct glycosylation with a traditional thioglycoside donor of GlcNAc, which otherwise affords poor glycosylation yields, one may obtain useful glycosylation results.
GLYCOSIDASE INHIBITORS AND USES THEREOF
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, (2014/03/25)
The invention provides compounds of Formula (I) for inhibiting gh cosidases, prodrugs of the compounds, and pharmaceutical compositions comprising the compounds or prodrugs of the compounds. The invention also provides method of treating diseases and diso
A synthetic approach to aromatic aminoglycoside as a neamine mimic
Inoue, Ryo,Matsuda, Sho,Oda, Yoshiki,Ooyama, Hirofumi,Yoshida, Akihiro,Hamasaki, Keita,Yamanoi, Takashi
scheme or table, p. 1335 - 1343 (2012/03/27)
This paper describes the synthetic approach to an aromatic a-glycoside as a mimic of neamine, which is a common core structure of some aminoglycoside antibiotics. We achieved the synthesis of the protected precursor of the neamine mimic, 4-(2,6-diamino-2,
1,5-Dideoxy-1,5-imino-D-glucitol Compounds
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Page/Page column 3, (2010/05/13)
1,5-Dideoxy-1,5-imino-D-glucitol compounds as shown in the specification. Also disclosed is a method of treating a hexosaminidase-associated disease.
Synthesis and Some Transformations of 2-Acetamido-5-amino-3,4,6-tri-O-benzyl-2,5-dideoxy-D-glucono-1,5-lactam
Granier, Thierry,Vasella, Andrea
, p. 865 - 880 (2007/10/03)
The lactam 21 was obtained in an overall yield of 72% from the hydroxy amide 16 by oxidation with the Dess-Martin periodinane, acid-catalysed isomerization of the oxidation products in toluene, whereupon 18/19 precipitated, and reductive dehydroxylation of 18/19 (Et3SiH/BF3 · OEt2; Scheme 1). The amide 16 was obtained by ammonolysis of the N-acetylglucosamine-derived lactone 15. Depending on the oxidation method, 16 yielded the keto amide 17, the hydroxy lactams 18/19, and the pyrrolidinecarboxamide 20 in widely different proportions. The pyrrolidinecarboxamide 20 was not reduced under the conditions of the reductive dehydroxylation. Hydrogenolysis of the benzyl-protected lactam 21 gave the trihydroxy lactam 22, while reduction with NaBH4/ BF3 · OEt2 led to the 2-acetamidopiperidine derivative 24 (Scheme 2). Selective (tert-butoxy)carbonylation of the lactam 21 (→ 25) followed by NaBH4 reduction and acid-catalysed solvolysis in EtOH led to the α-ethoxycarbamates 28/29. Similarly, (tert-butoxy)carbonylation of 1 (→ 31) followed by reduction to 32/33 and glycosidation yielded the ethoxycarbamate 34. Treatment of the GlcNAc-derived ethyl glycosides 28/29 with Me3SiCN/ BF3 · OEt2 gave the equatorial amino nitrile 30. Under similar conditions, the Glc-derived glycoside 34 led to the iminooxazolidinone 35. In the presence of a larger proportion of Me3SiCN at 5°, 34 was transformed into the axial, selectively monodebenzylated amino nitrile 36.
Stereocontrolled Synthesis of α-C-Galactosamine Derivatives via Chelation-Controlled C-Glycosylation
Urban, Dominique,Skrydstrup, Troels,Beau, Jean-Marie
, p. 2507 - 2516 (2007/10/03)
The samarium diiodide-promoted reduction of 2-deoxy-2-acetamidogalactosyl pyridyl sulfone α-5 with ketones or aldehydes under Barbier conditions led unexpectedly to the stereoselective synthesis of α-C-galactosamine derivatives in good yields. With carbon
C-glycosides: A stereoselective synthesis of α-C-galactosamines with a glycosyl dianion
Burkhart, Fred,Kessler, Horst
, p. 255 - 256 (2007/10/03)
α-C-glycosides of the galactosamine can be obtained from the configurationally stable α-glycosyl dianion which can be prepared by reductive lithiation of the chloride. Different electrophiles react selectively at the anomeric center.
127. C-glycoside analogues of N4-(2-Acetamido-2-deoxy-β-D-glucopyranosyl)-L-asparagine: synthesis and conformational analysis of a cyclic C-glycopeptide
Hoffmann, Matthias,Burkhart, Fred,Hessler, Gerhard,Kessler, Horst
, p. 1519 - 1532 (2007/10/03)
The synthesis of C-glycosidic analogues 15-22 of N4-(2-acetamido-2-deoxy-β-D-glucopyranosyl)-L-asparagine (ASn(N4GlcNAc)) possessing a reversed amide bond as an isosteric replacement of the N-glycosidic linkage is presented. The peptide cyclo(-D-Pro-Phe-Ala-CGaa-Phe-Phe-) (CGaa = C-glycosylated amino acid; 24) was prepared to demonstrate that 3-[(3-acetamido-2,6-anhydro-4,5,7-tri-O-benzyl-3-deoxy-β-D-glycero-D- guloheptonoyl)amino]-2-[(9H-fluoren-9-yloxycarbonyl)amino]propanoic acid (22) can be used in solid-phase peptide synthesis. The conformation of 24 was determined by NMR and molecular-dynamics (MD) techniques. Evidence is provided that the CGaa side chain interacts with the peptide backbone. The different C-glycosylated amino acids 15-21 were prepared by coupling 3-acetamido-2,6-anhydro-4,5,7-tri-O-benzyl-3-deoxy-β-D-glycero-D-gulo- heptonic acid (4) with diamino-acid derivatives 8-14 in 83-96% yield. The synthesis of 4 was performed from 2-(acetamido-3,4,6-tri-O-benzyl-2-deoxy-β-D-glucopyranosyl)tributylstannane (2) by treatment with BuLi and CO2 in 83% yield. Similarly, propyl isocyanat yielded the glycoheptonamide 7 in 52% from 2. Compound 2 was obtained from 2-acetamido-3,4,6-tri-O-benzyl-2-deoxy-D-glucopyranose (1) by chlorination and addition of tributyltinlithium in 74% yield. A procedure for a multigram-scale synthesis of 1 is given.
Convenient preparation of perbenzylated 2-Azido and 2-N-acetylamino-2-deoxy-D-hexono-1,5-lactones by oxidation of the corresponding lactols
Ayadi, Ebtissam,Czernecki, Stanislas,Xie, Juan
, p. 191 - 199 (2007/10/03)
2-Azido-3,4,6-tri-O-benzyl-2-deoxy-D-galacto, gluco and mannopyranoses (1, 2, 3) were oxidized with DMSO in the presence of acetic anhydride. From 1 and 2 the corresponding lactone derivatives were obtained in good yield (89-92%), whereas from 3, glucono-1,5-lactone was obtained (92%) after complete epimerization at C-2. 2-N-Acetylamino-3,4,6-tri-O-benzyl-2-deoxy-D-galacto, gluco and mannopyranoses (7, 8, 9) were obtained from the corresponding 2-azido phenylselenoglycopyranosides (13, 14, 15) by reduction, N-acetylation and hydrolysis catalyzed by mercury trifluoroacetate. Oxidation of 7 and 8 by tetra-n-propylammonium tetra-oxoruthenate (VII) in the presence of 4-methylmorpholine-N-oxide afforded the corresponding lactones in good yield (90%) and high purity. Epimerization at C-2 occurred during oxidation of 9 and perbenzylated D-glucono-1,5-lactone (11) was obtained (90%).
