- Design, physico-chemical characterization andin vitrobiological activity of organogold(iii) glycoconjugates
-
To develop new metal-based glycoconjugates as potential anticancer agents, four organometallic gold(iii)-dithiocarbamato glycoconjugates of the type [AuIII(2-Bnpy)(SSC-Inp-GlcN)](PF6) (2-Bnpy: 2-benzylpyridine; Inp: isonipecotic moie
- Pettenuzzo, Andrea,Vezzù, Keti,Di Paolo, Maria Luisa,Fotopoulou, Eirini,Marchiò, Luciano,Via, Lisa Dalla,Ronconi, Luca
-
supporting information
p. 8963 - 8979
(2021/07/02)
-
- Synthetic development of sugar amino acid oligomers towards novel podophyllotoxin analogues
-
In this work, we have developed an approach for the synthesis of sugar amino acid oligomers based on the glucosamine scaffold. We found that the solid-phase approach was unsuccessful for the preparation of sugar amino acid oligomers and the limitation of
- Bouchard, Megan,Tremblay, Thomas,Paré-Lacroix, Marie-Pier,Gagné-Boulet, Mathieu,Fortin, Sébastien,Giguère, Denis
-
-
- Synthesis of a Glycosylphosphatidylinositol (GPI) Fragment as a Potential Substrate for Mannoprotein Transglycosidases
-
A glycophosphatidylinositol tetrasaccharide fragment was synthesized to mimic the core features of primary model, that of Saccharomyces cerevisiae. The salient feature of this approach is centered on the quick access to various α-1,2- and α-1,6-mannosyl a
- Belz, Tyson F.,Williams, Spencer J.
-
p. 2053 - 2058
(2021/08/31)
-
- Ultrasonication-Assisted Synthesis of a d-Glucosamine-Based β-CD Inclusion Complex and Its Application as an Aqueous Heterogeneous Organocatalytic System
-
For the first time, an inclusion complex has been crafted between a carbohydrate-based molecule and a β-cyclodextrin (CD) hydrophobic cavity for asymmetric catalytic applications. This novel d-glucosamine-based inclusion compound has been synthesized in h
- Rani, Dhiraj,Sethi, Aaftaab,Kaur, Khushwinder,Agarwal, Jyoti
-
p. 9548 - 9557
(2020/09/09)
-
- Further, Small-Molecule Pyrolysis Products Derived from Chitin
-
In an ongoing study of the products formed on pyrolysis of chitin (4) under a range of conditions, we now detail the isolation and characterisation of the crystalline and hitherto undetected pyridine N-oxide 18 and enamide 19. Pathways for the formation of these products have been proposed and subjected to both experimental and computational assessment.
- Nikahd, Maryam,Mikusek, Jiri,Banwell, Martin G.,Yu, Li-Juan,Coote, Michelle L.,Gardiner, Michael G.
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p. 1187 - 1196
(2020/08/25)
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- Regioselective Manipulation of GlcNAc Provides Allosamine, Lividosamine, and Related Compounds
-
Palladium-catalyzed oxidation of isopropyl N-acetyl-α-d-glucosamine (GlcNAc) is used to prepare the rare sugars allosamine, lividosamine, and related compounds with unprecedented selectivity. The Passerini reaction applied on 3-keto-GlcNAc provides an ent
- Zhang, Ji,Eisink, Niek N.H.M.,Witte, Martin D.,Minnaard, Adriaan J.
-
supporting information
p. 516 - 525
(2019/01/14)
-
- Methyl glycosides via Fischer glycosylation: translation from batch microwave to continuous flow processing
-
Abstract: A continuous flow procedure for the synthesis of methyl glycosides (Fischer glycosylation) of various monosaccharides using a heterogenous catalyst has been developed. In-depth analysis of the isomeric composition was undertaken and high consistency with corresponding results observed under microwave heating was obtained. Even in cases where addition of water was needed to achieve homogeneity—a prerequisite for the flow experiments—no detrimental effect on the conversion was found. The scalability was demonstrated on a model case (mannose) and as part of the target-oriented synthesis of d-glycero-d-manno heptose, both performed on multigram scale.
- Aronow, Jonas,Stanetty, Christian,Baxendale, Ian R.,Mihovilovic, Marko D.
-
-
- Kinetically Controlled Fischer Glycosidation under Flow Conditions: A New Method for Preparing Furanosides
-
Kinetically controlled Fischer glycosidation was achieved under flow conditions. β-Hydroxy-substituted sulfonic acid functionalized silica (HO-SAS) was used as an acid catalyst. This reaction directly converted aldohexoses into kinetically favored furanosides to enable the practical synthesis of furanosides. After optimization of the reaction temperature and residence time, glucofuranosides, galactofuranosides, and mannofuranosides were synthesized in good yields.
- Masui, Seiji,Manabe, Yoshiyuki,Hirao, Kohtaro,Shimoyama, Atsushi,Fukuyama, Takahide,Ryu, Ilhyong,Fukase, Koichi
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supporting information
p. 397 - 400
(2019/02/26)
-
- Triazole Linked N-Acetylglucosamine Based Gelators for Crude Oil Separation and Dye Removal
-
Marine oil-spills have a long-lasting impact on the environment; therefore, it is a major concern in the scientific community to find a solution for remediation. Recently, phase selective organo-gelators emerged as potential materials for removal of oil from water through selective gelation. Herein, we report synthesis of a series of C-6 triazole linked N-acetylglucosamine derivatives, among which three have shown excellent selective gelation of organic solvents, diesel, petrol, and crude oils in water and seawater. We have studied phase selective gelation against different API grade crude oils (from light to heavy), and the gelation was achieved using nontoxic carrier solvent at room temperature in less than 15 min, and gelators were found useful for recovering crude oils. Critical gel concentration (CGC) of crude oil gelators was found to be 2.3-12% (w/v). The variable temperature NMR and FTIR experiments reveal that intermolecular hydrogen bonding was responsible for gel formation. Furthermore, a gelator was utilized for selective dye removal from water.
- Narayana, Chintam,Kumari, Priti,Tiwari, Ghanshyam,Sagar, Ram
-
p. 16803 - 16812
(2019/12/27)
-
- From d-to l-Monosaccharide Derivatives via Photodecarboxylation-Alkylation
-
Photodecarboxylation-alkylation of conformationally locked monosaccharides leads to inversion of stereochemistry at C5. This allows the synthesis of l-sugars from their readily available d-counterparts. Via this strategy, methyl l-guloside was synthesized from methyl d-mannoside in 21% yield over six steps.
- Wan, I. C. Steven,Witte, Martin D.,Minnaard, Adriaan J.
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supporting information
p. 7669 - 7673
(2019/10/08)
-
- An innovative and efficient route to the synthesis of metal-based glycoconjugates: proof-of-concept and potential applications
-
With a view to developing more efficient strategies to the functionalization of metallodrugs with carbohydrates, we here report on an innovative and efficient synthetic route to generate gold(iii) glycoconjugates in high yields and purity. The method is based on the initial synthesis of the zinc(ii)-dithiocarbamato intermediate [ZnII(SSC-Inp-GlcN)2] (Inp = isonipecotic moiety; GlcN = amino-glucose) followed by the transfer of the glucoseisonipecoticdithiocarbamato ligand to the gold(iii) center via transmetallation reaction between the zinc(ii) intermediate and K[AuIIIBr4] in 1?:?2 stoichiometric ratio, yielding the corresponding glucose-functionalized gold(iii)-dithiocarbamato derivative [AuIIIBr2(SSC-Inp-GlcN)]. No protection/deprotection of the amino-glucose scaffold and no chromatographic purification were needed. The synthetic protocol was optimized for glucose precursors bearing the amino function at either the C2 or the C6 position, and works in the case of both α and β anomers. The application of the synthetic strategy was also successfully extended to other metal ions of biomedical interest, such as gold(i) and platinum(ii), to obtain [AuI(SSC-Inp-GlcN)(PPh3)] and [PtII(SSC-Inp-GlcN)2], respectively. All compounds were fully characterized by elemental analysis, mid- and far-IR, mono- and multidimensional NMR spectroscopy, and, where possible, X-ray crystallography. Results and potential applications are here discussed.
- Pettenuzzo, Andrea,Montagner, Diego,McArdle, Patrick,Ronconi, Luca
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supporting information
p. 10721 - 10736
(2018/08/17)
-
- New phosphine-imine and phosphine-amine ligands derived from D-gluco-, D-galacto- and D-allosamine in Pd-catalysed asymmetric allylic alkylation
-
New phosphine-imine and phosphine-amine chiral ligands which were easily prepared from D-gluco-, D-galacto- and D-allosamine furnished a high level of enantiomeric excess (up to 99%) in the Pd(0)-catalysed asymmetric allylic alkylation of racemic 1,3-diphenyl-2-propenyl acetate with malonates.
- Szulc, Izabela,Ko?odziuk, Robert,Zawisza, Anna
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p. 1476 - 1485
(2018/02/19)
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- Ring-Opening Reactions of the N-4-Nosyl Hough-Richardson Aziridine with Nitrogen Nucleophiles
-
Dinosylated α-d-glucopyranoside was directly transformed into α-d-altropyranosides via in situ formed N-4-nosyl Hough-Richardson aziridine with nitrogen nucleophiles under mild conditions in fair to excellent yields. The scope of the aziridine ring-opening reaction was substantially broadened contrary to the conventional methods introducing solely the azide anion at high temperatures. If necessary, the N-4-nosyl Hough-Richardson aziridine can be isolated by filtration in a very good yield and high purity.
- Ru?il, Tomá?,Trávní?ek, Zdeněk,Canka?, Petr
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p. 723 - 730
(2017/04/26)
-
- Synthesis and Study of Molecular Assemblies Formed by 4,6-O-(2-Phenylethylidene)-Functionalized d -Glucosamine Derivatives
-
Low-molecular-weight gelators are interesting small molecules with potential applications as advanced materials. Carbohydrate-based small molecular gelators are especially useful because they are derived from renewable resources and are more likely to be biocompatible and biodegradable. Various 4,6-benzylidene acetal protected α-methyl 2-d-glucosamine derivatives have been found to be effective low-molecular-weight gelators. To understand the influence of the 4,6-benzylidene acetal functional group toward molecular self-assembly and to obtain effective molecular gelators, we synthesized and analyzed a new series of d-glucosamine derivatives in which the phenyl group of the acetal is replaced by a benzyl group. The homologation of the acetal protection from aromatic to aliphatic functional groups allows us to probe the effect of increasing structural flexibility on molecular self-assembly and gelation. In this study, nine representative amides and nine urea analogs were synthesized, and their gelation properties were analyzed in a series of organic solvents and aqueous solutions. The resulting amide and urea derivatives are versatile organogelators forming gels in toluene, ethanol, isopropanol, ethylene glycol, and aqueous mixtures of organic solvents. More interestingly, the amide analogs are also effective gelators for pump oil and engine oil. NMR spectroscopy at variable temperatures was used to analyze the molecular assemblies and intermolecular forces. The selected gelators with several drug and dye molecules in DMSO and water were studied for their effectiveness of encapsulation and release of these agents.
- Chen, Anji,Adhikari, Surya B.,Mays, Kellie,Wang, Guijun
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p. 8076 - 8089
(2017/08/21)
-
- A versatile carbohydrate based gelator for oil water separation, nanoparticle synthesis and dye removal
-
A versatile green gelator suitable for multiple applications is reported. Gelation of organic solvents in a significantly low gelation time (5 s) is achieved. The effect of cooling and sonication on gelation time is investigated. Apart from organic solve
- Narayana, Chintam,Upadhyay, Ravi Kant,Chaturvedi, Raman,Sagar, Ram
-
supporting information
p. 2261 - 2267
(2017/03/22)
-
- Sugar derived alkamine catalytic imine reduction method
-
The invention discloses a method used for catalytic reduction of imine with saccharide-derivatized amino alcohol. According to the method, imine is taken as a substrate. The method comprises following steps: 1) imine and saccharide-derivatized amino alcohol are dissolved in an organic solvent I, wherein molar ratio of imine to saccharide-derivatized amino alcohol ranges from 100:1-20; 2) trichlorosilane with 1.5 to 5 times equivalent weights is added into a solution obtained via step 1) dropwise, an obtained mixture is stirred and reacted for 12 to 36h at a temperature of -20 to 40 DEG C, and a saturated sodium bicarbonate solution is used for quenching; 3) a material obtained via step 2) is extracted with an organic solvent II, and is subjected to column chromatography isolation so as to obtain amine compounds.
- -
-
Paragraph 0035; 0036; 0037
(2016/10/07)
-
- Synthetic heparin pentasaccharides
-
Preparation and use of synthetic monosaccharides, disaccharides, trisaccharides, tetrasaccharides and pentasaccharides useful for the preparation of synthetic heparinoids.
- -
-
Page/Page column 36; 37
(2016/02/12)
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- Studies toward the synthesis of linear triazole linked pseudo oligosaccharides and the use of ferrocene as analytical probe
-
Three different building blocks have been synthesised and used for the synthesis of linear triazole linked pseudo oligosaccharides with copper(I)-catalysed cycloaddition (CuAAC). Ethynylferrocene has been used as analytical probe to improve the UV/Vis pro
- Schmidt, Magnus S.,G?tz, Kathrin H.,Koch, Wolfgang,Grimm, Tanja,Ringwald, Markus
-
-
- Chemo-enzymatic approach to access diastereopure α-substituted GlcNAc derivatives
-
The formation of diastereopure α-substituted GlcNAc derivatives in a simple and straightforward way is a challenging task. Herein, we report the chemical synthesis of diastereomeric α/β-substituted GlcNAc derivatives under non-anhydrous atmosphere using u
- Wang, Su-Yan,Laborda, Pedro,Lu, Ai-Min,Wang, Meng,Duan, Xu-Chu,Liu, Li,Voglmeir, Josef
-
p. 423 - 434
(2017/08/23)
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- PRODUCTION METHOD OF ALKYL N-ACETYLGLUCOSAMINIDE
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PROBLEM TO BE SOLVED: To provide a method for obtaining alkyl N-acetylglucosaminide that comprises few content of N-acetyl glucosamine as impurities, conveniently and efficiently with a low cost. SOLUTION: The invention provides a production method of alkyl N-acetylglucosaminide comprising a step of reducing the content of N-acetyl glucosamine by contacting a mixture of alkyl N-acetylglucosaminide and N-acetyl glucosamine with strongly basic anion exchange resin (where, alkyl means an alkyl group of carbon number 1-4). The invention relates to the production method of alkyl N-acetylglucosaminide which is a mixture of alkyl N-acetylglucosaminide and N-acetyl glucosamine obtained by reaction of N-acetyl glucosamine, chitin, or chitin oligosaccharide with alkyl alcohol under the presence of an acid, or transglycosidation of chitin or chitin oligosaccharide using an enzyme with N-acetylhexosaminidase activity in a mixed solution of alkyl alcohol and water. COPYRIGHT: (C)2016,JPOandINPIT
- -
-
Paragraph 0034; 0035
(2016/12/01)
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- N-acetylgalactosamine green synthetic method
-
The present invention discloses a N-acetylgalactosamine green synthetic method. According to the method, N-acetylglucosamine as a raw material is successively condensed with an alcohol and pivaloyl chloride, and then N-acetylgalactosamine can be obtained
- -
-
Paragraph 0037; 0038
(2016/11/28)
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- Catalytic Depolymerization of Chitin with Retention of N-Acetyl Group
-
Chitin, a polymer of N-acetylglucosamine units with β-1,4-glycosidic linkages, is the most abundant marine biomass. Chitin monomers containing N-acetyl groups are useful precursors to various fine chemicals and medicines. However, the selective conversion of robust chitin to N-acetylated monomers currently requires a large excess of acid or a long reaction time, which limits its application. We demonstrate a fast catalytic transformation of chitin to monomers with retention of N-acetyl groups by combining mechanochemistry and homogeneous catalysis. Mechanical-force-assisted depolymerization of chitin with a catalytic amount of H2SO4 gave soluble short-chain oligomers. Subsequent hydrolysis of the ball-milled sample provided N-acetylglucosamine in 53 % yield, and methanolysis afforded 1-O-methyl-N-acetylglucosamine in yields of up to 70 %. Our process can greatly reduce the use of acid compared to the conventional process.
- Yabushita, Mizuho,Kobayashi, Hirokazu,Kuroki, Kyoichi,Ito, Shogo,Fukuoka, Atsushi
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p. 3760 - 3763
(2015/12/08)
-
- Diaminohexopyranosides as ligands in half-sandwich ruthenium(II), rhodium(III), and iridium(III) complexes
-
The syntheses of methyl 2,3-diamino-4,6-O-benzylidene-2,3-dideoxy-α-d-hexopyranosides of glucose, mannose, gulose, and talose and methyl 2-amino-4,6-benzylidene-2,3-dideoxy-3-tosylamido-α-d-glucopyranoside are exhaustively presented, as well as their application as ligands in half-sandwich ruthenium(II), rhodium(III), and iridium(III) complexes. The complex formation occurs highly diastereoselectively, creating a stereogenic metal center. The molecular structures of the ligands and their complexes were investigated by X-ray structure analysis, NMR spectroscopy, polarimetry, and DFT methods. The diamino monosaccharide complexes have been subjected to antitumor activity studies. In vitro tests of a few ruthenium complexes against different cancer cell types showed antiproliferative activities 4-10 times lower than that of cisplatin.
- B?ge, Matthias,Fowelin, Christian,Bednarski, Patrick,Heck, Jürgen
-
supporting information
p. 1507 - 1521
(2015/05/13)
-
- D-Glucosamine as a novel chiral auxiliary for the stereoselective synthesis of P-stereogenic phosphine oxides
-
D-Glucosamine was successfully employed as a chiral auxiliary for the enantioselective synthesis of phosphine oxides. The influence of the anomeric position was also investigated and revealed the excellent ability of the α-anomer to perform this transform
- D'Onofrio,Copey,Jean-Gérard,Goux-Henry,Pilet,Andrioletti,Framery
-
supporting information
p. 9029 - 9034
(2015/09/01)
-
- A de Novo-Designed Monomeric, Compact Three-Helix-Bundle Protein on a Carbohydrate Template
-
De novo design and chemical synthesis of proteins and of other artificial structures that mimic them is a central strategy for understanding protein folding and for accessing proteins with new functions. We have previously described carbohydrates that act as templates for the assembly of artificial proteins, so-called carboproteins. The hypothesis is that the template preorganizes the secondary structure elements and directs the formation of a tertiary structure, thus achieving structural economy in the combination of peptide, linker, and template. We speculate that the structural information from the template could facilitate protein folding. Here we report the design and synthesis of three-helix-bundle carboproteins on deoxyhexopyranosides. The carboproteins were analyzed by CD, analytical ultracentrifugation (AUC), small-angle X-ray scattering (SAXS), and NMR spectroscopy, and this revealed the formation of the first compact and folded monomeric carboprotein, distinctly different from a molten globule. En route to this carboprotein we observed a clear effect originating from the template on protein folding.
- Malik, Leila,Nygaard, Jesper,Cristensen, Niels J.,Madsen, Charlotte S.,R?sner, Heike I.,Kragelund, Birthe B.,Hoiberg-Nielsen, Rasmus,Streicher, Werner W.,Arleth, Lise,Thulstrup, Peter W.,Jensen, Knud J.
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p. 1905 - 1918
(2015/09/02)
-
- Inhibition of microbial β-N-acetylhexosaminidases by 4-deoxy- and galacto-analogues of NAG-thiazoline
-
NAG-thiazoline is a well-established competitive inhibitor of two physiologically relevant glycosidase families - β-N-acetylhexosaminidases (GH20) and β-N-acetylglucosaminidases (GH84). Based on the different substrate flexibilities of these enzyme groups, we designed and synthesized the 4-deoxy derivative of NAG-thiazoline aiming at the selective inhibition of GH20 β-N-acetylhexosaminidases. One GH84 and two GH20 microbial glycosidases were employed as model enzymes for the inhibition assays. Surprisingly, the new compound 4-deoxy-thiazoline exhibited no activity inhibition with either of the enzyme families of interest. Unlike with the substrates, the 4-hydroxyl group of the inhibitor's sugar ring seems to be crucial for binding the inhibitor to the active sites of these enzymes.
- Krejzov, Jana,Kalachova, Lubica,imon, Petr,Pelantov, Helena,Slmov, Kristna,Ken, Vladimr
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p. 5321 - 5323
(2015/01/08)
-
- Synthesis and characterization of pH responsive D-glucosamine based molecular gelators
-
Small molecular gelators are a class of compounds with potential applications for soft biomaterials. Low molecular weight hydrogelators are especially useful for exploring biomedical applications. Previously, we found that 4,6-O-benzylidene acetal protect
- Goyal, Navneet,Mangunuru, Hari P.R.,Parikh, Bargav,Shrestha, Sonu,Wang, Guijun
-
supporting information
p. 3111 - 3121
(2015/03/03)
-
- Novel phosphoramidate prodrugs of N-acetyl-(d)-glucosamine with antidegenerative activity on bovine and human cartilage explants
-
(d)-Glucosamine and other nutritional supplements have emerged as safe alternative therapies for osteoarthritis (OA), a chronic and degenerative articular joint disease. In our preceding paper, a series of novel O-6 phosphate N-acetyl (d)-glucosamine prod
- Serpi, Michaela,Bibbo, Rita,Rat, Stephanie,Roberts, Helen,Hughes, Claire,Caterson, Bruce,Alcaraz, María José,Gibert, Anna Torrent,Verson, Carlos Raul Alaez,McGuigan, Christopher
-
supporting information; experimental part
p. 4629 - 4639
(2012/07/01)
-
- Synthesis and characterization of monosaccharide derivatives and application of sugar-based prolinamides in asymmetric synthesis
-
For the first time, the β-anomer of N-acetylglucosamine derivative methyl 2-acetamido-3,4,6-tri-O-benzyl-2-deoxy-β-D-glucopyranoside (9b) was synthesized, isolated, and used in the synthesis of sugar-based primary amine 4b. Sugar-based primary amine 5a, a
- Agarwal, Jyoti,Peddinti, Rama Krishna
-
p. 6390 - 6406,17
(2020/09/16)
-
- Glucosamine-based primary amines as organocatalysts for the asymmetric aldol reaction
-
Glucosamine derivatives have been synthesized starting from commercially available N-acetyl-D-glucosamine/glucosamine hydrochloride and have been employed successfully as efficient organocatalysts for the direct asymmetric aldol reaction between cyclohexa
- Agarwal, Jyoti,Peddinti, Rama Krishna
-
scheme or table
p. 3502 - 3505
(2011/06/21)
-
- Oligo-Aminosaccharide compound
-
An oligo-aminosaccharide compound formed by binding 3 to 6 saccharides, such as 2,6-diamino-2,6-dideoxy-α-(1→4)-D-glucopyranose oligomers, or a salt thereof, which has high affinity to a double-stranded nucleic acid.
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Page/Page column 8
(2011/01/12)
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- Synthesis and characterization of d-glucosamine-derived low molecular weight gelators
-
Carbohydrate-based low molecular weight gelators are an interesting class of molecules with many potential applications. Previously, we have found that certain esters and carbamates of 4,6-O-benzylidene-α-d-methyl- glucopyranoside are low molecular weight
- Goyal, Navneet,Cheuk, Sherwin,Wang, Guijun
-
supporting information; experimental part
p. 5962 - 5971
(2010/09/18)
-
- Amide Cis-trans isomerization in aqueous solutions of methyl N -Formyl- d -glucosaminides and Methyl N -Acetyl- d -glucosaminides: Chemical equilibria and exchange kinetics
-
Amide cis-trans isomerization (CTI) in methyl 2-deoxy-2-acylamido-d- glucopyranosides was investigated by 1H and 13C NMR spectroscopy. Singly 13C-labeled methyl 2-deoxy-2-formamido-d- glucopyranoside (MeGlcNFm) anomers provided standard 1H and 13C chemical shifts and 1H-1H and 13C-13C spin-coupling constants for cis and trans amides that are detected readily in aqueous solution. Equipped with this information, doubly 13C-labeled methyl 2-deoxy-2-acetamido-d-glucopyranoside (MeGlcNAc) anomers were investigated, leading to the detection and quantification of cis and trans amides in this biologically important aminosugar. In comparison to MeGlcNFm anomers, the percentage of cis amide in aqueous solutions of MeGlcNAc anomers is small (～23% for MeGlcNFm versus ～1.8% for MeGlcNAc at 42 °C) but nevertheless observable with assistance from 13C-labeling. Temperature studies gave thermodynamic parameters δG°, δH°, and δS° for cis-trans interconversion in MeGlcNFm and MeGlcNAc anomers. Cis/trans equilibria depended on anomeric configuration, with solutions of α-anomers containing less cis amide than those of β-anomers. Confirmation of the presence of cis amide in MeGlcNAc solutions derived from quantitative 13C saturation transfer measurements of CTI rate constants as a function of solution temperature, yielding activation parameters Eact, δG° ?, δH°-, and δS° ? for saccharide CTI. Rate constants for the conversion of trans to cis amide in MeGlcNFm and MeGlcNAc anomers ranged from 0.02 to 3.59 s-1 over 31-85 °C, compared to 0.24-80 s-1 for the conversion of cis to trans amide over the same temperature range. Energies of activation ranged from 16-19 and 19-20 kcal/mol for the cis → trans and trans → cis processes, respectively. Complementary DFT calculations on MeGlcNFm and MeGlcNAc model structures were conducted to evaluate the effects of an acyl side chain and anomeric structure, as well as C2-N2 bond rotation, on CTI energetics. These studies show that aqueous solutions of GlcNAc-containing structures contain measurable amounts of both cis and trans amides, which may influence their biological properties.
- Hu, Xiaosong,Zhang, Wenhui,Carmichael, Ian,Serianni, Anthony S.
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experimental part
p. 4641 - 4652
(2010/06/18)
-
- Accessible sugars as asymmetric olefin epoxidation organocatalysts: Glucosaminide ketones in the synthesis of terminal epoxides
-
A systematically varied series of conformationally restricted ketones, readily prepared from N-acetyl-d-glucosamine, were tested against representative olefins as asymmetric epoxidation catalysts showing useful selectivities against terminal olefins and, in particular, typically difficult 2,2-disubstituted terminal olefins.
- Boutureira, Omar,McGouran, Joanna F.,Stafford, Robert L.,Emmerson, Daniel P. G.,Davis, Benjamin G.
-
supporting information; experimental part
p. 4285 - 4288
(2009/12/05)
-
- Protecting group free glycosidations using p-toluenesulfonohydrazide donors
-
(Figure Presented) N-Glycopyranosylsulfonohydrazides are introduced as glycosyl donors for protecting group free synthesis of O-glycosides, glycosyl azides, and oxazolines. Mono- and disaccharides containing a reducing terminal N-acelylglucosamine residue were condensed with p-toluenesulfonylhydrazide to give the desired β-D-pyranose donors. These donors can be activated with NBS and then glycosidated with the desired alcohol or transformed to the oxazoline or glycosyl azide.
- Gudmundsdottir, Anna V.,Nitz, Mark
-
supporting information; scheme or table
p. 3461 - 3463
(2009/04/16)
-
- Synthesis of Tc-99m labeled glucosamino-Asp-cyclic(Arg-Gly-Asp-d-Phe-Lys) as a potential angiogenesis imaging agent
-
Angiogenesis imaging agents for single photon emission computed tomography (SPECT) play a role in diagnosing tumor-induced angiogenesis as well as tumor metastasis. We synthesized and evaluated radiolabeled RGD glycopeptides by incorporation of the [
- Lee, Byung Chul,Sung, Hyun Ju,Kim, Ji Sun,Jung, Kyung-Ho,Choe, Yearn Seong,Lee, Kyung-Han,Chi, Dae Yoon
-
p. 7755 - 7764
(2008/03/28)
-
- A 1-acetamido derivative of 6-epi-valienamine: An inhibitor of a diverse group of β-N-acetylglucosaminidases
-
The synthesis of an analogue of 6-epi-valienamine bearing an acetamido group and its characterisation as an inhibitor of β-N- acetylglucosaminidases are described. The compound is a good inhibitor of both human O-GlcNAcase and human β-hexosaminidase, as well as two bacterial β-N-acetylglucosaminidases. A 3-D structure of the complex of Bacteroides thetaiotaomicron BtGH84 with the inhibitor shows the unsaturated ring is surprisingly distorted away from its favoured solution phase conformation and reveals potential for improved inhibitor potency. This journal is The Royal Society of Chemistry.
- Scaffidi, Adrian,Stubbs, Keith A.,Dennis, Rebecca J.,Taylor, Edward J.,Davies, Gideon J.,Vocadlo, David J.,Stick, Robert V.
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p. 3013 - 3019
(2008/04/01)
-
- Synthesis and structure-activity relationships of truncated bisubstrate inhibitors of aminoglycoside 6′-N-acetyltransferases
-
Truncated aminoglycoside-coenzyme A bisubstrate analogues were efficiently prepared using a convergent approach where the amine and the thiol are coupled in one pot with the addition of a linker, without the need for protecting groups. These derivatives were tested for their effect on the activity of the resistance-causing enzyme aminoglycoside 6′-N-acetyltransferase Ii, and key structure-activity relationships are reported. Moreover, one of the inhibitors is able to block aminoglycoside resistance in cells expressing this enzyme.
- Gao, Feng,Yan, Xuxu,Shakya, Tushar,Baettig, Oliver M.,Ait-Mohand-Brunet, Samia,Berghuis, Albert M.,Wright, Gerard D.,Auclair, Karine
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p. 5273 - 5281
(2007/10/03)
-
- Inhibitors of aminoglycoside 6'-N-acetyltransferases, compositions and uses thereof
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The present invention relates to inhibitors of aminoglycoside 6''-N-acetyltransferases of Formula I: R-X-Y-Z Formula I wherein: R is selected from the group consisting of: R1 is selected from the group consisting of OH and R2 is selected from the group consisting of OH and R3 is selected from the group consisting of NH2 and OH; R4 is selected from the group consisting of NH2 and R5 is selected from the group consisting of OMe, OEt OPr, and O-iPr; X is selected from the group consisting of NH and O; Y is selected from the group consisting of: R6 is selected from the group consisting of OH, CH3, and OCH3; n is an integer ranging from 1 to 10; and Z is selected from the group consisting of: and R7 is selected from the group consisting of OH, OMe, OEt OPr, O-iPr, O-tBu and
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Page/Page column 17
(2008/06/13)
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- Microwave-accelerated Fischer glycosylation
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Fischer glycosylation has been used for decades for the synthesis of simple alkyl and aryl glycosides from free sugars. The reaction proceeds under reflux in the presence of catalytic acid with the alcohol as solvent. The main deficiency of this reaction is the long reaction time required. In this study microwave heating has been utilised for the Fischer glycosylation reaction of N-acetyl-d-glucosamine, N-acetyl-d-galactosamine, d-glucose, d-galactose and d-mannose with a variety of alcohols (methanol, ethanol, benzyl alcohol and allyl alcohol). Remarkable acceleration of the glycosylation reactions (minutes compared to hours) over conventional reflux heating was observed with good yields and production of the α-glycoside as the dominant product.
- Bornaghi, Laurent F.,Poulsen, Sally-Ann
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p. 3485 - 3488
(2007/10/03)
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- Carbohydrate-derived aminoalcohol ligands for asymmetric Reformatsky reactions
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Members of a family of functionally and stereochemically diverse d-glucosamine-derived tertiary aminoalcohol ligands have been used to promote the asymmetric Reformatsky reaction. The β-hydroxyester product tert-butyl 3-phenyl-3-hydroxy-propanoate was obt
- Emmerson, Daniel P.G.,Hems, William P.,Davis, Benjamin G.
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p. 213 - 221
(2007/10/03)
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- Synthesis of two oligosaccharides, the GPI anchor glycans from S. cerevesiae and A. fumigatus
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Two oligosaccharides, α-D-Manp-(1→2)-α-D-Manp-(1→2)- α-D-Manp-(1→6)-α-D-Manp-(1→4)-α-D-GlcpNAc (I) and α-D-Manp-(1→3)-α-D-Manp-(1→2)-α-D-Manp-(1→2) -α-D-Manp-(1→6)-α-D-Manp-(1→4)-α-D-GlcpNAc (II), the glycosylphosphatidylinositol (GPI) anchor glycans from
- Ma, Zuchao,Zhang, Jianjun,Kong, Fanzuo
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- An efficient synthesis of derivatives of 2-acetamido-4-amino-2,4,6- trideoxy-D-galactopyranose
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Methyl 2-acetamido-4-amino-2,4,6-trideoxy-α-D-galactopyranoside (10) was synthesized from D-glucosamine hydrochloride in eight steps in an overall yield of 31%. Key steps include the selective benzoylation at O-3 of methyl 2-acetamido-2,6-dideoxy-α-D-glucopyranoside in 89% yield and the subsequent Mitsunobu reaction using diphenylphosphoryl azide as the azide source which proceeded in 92% yield. Di- and mono-benzyloxycarbonyl derivatives of 10 were also prepared. Copyright
- Liang, Hong,Grindley
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- Precise structure activity relationships in asymmetric catalysis using carbohydrate scaffolds to allow ready fine tuning: dialkylzinc-aldehyde additions.
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The ready construction of 24 stereochemically and functionally diverse carbohydrate ligand structures from a core D-glucosamine scaffold has allowed the evaluation of broad ranging structure activity relationships in ligand accelerated zincate additions t
- Emmerson, Daniel P G,Villard, Renaud,Mugnaini, Claudia,Batsanov, Andrei,Howard, Judith A K,Hems, William P,Tooze, Robert P,Davis, Benjamin G
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p. 3826 - 3838
(2007/10/03)
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- Novel disaccharides with anti-arthrosic properties
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The invention relates to novel disaccharides of formula (I), wherein R1 is selected from the group consisting of hydrogen, linear or branched (C1-C4) alkyl, phenylalkyl with less than ten carbon atoms and —COCH3; R2 is selected from the group consisting of hydrogen, —COCH3 and SO3M; R3 is selected from the group consisting of hydrogen, linear or branched (C1-C4) alkyl, phenylalkyl with less than ten carbon atoms, —COCH3 and y —COPh, Ph being phenyl; G is selected from amongst —COOR4 and —COOM, R4 is selected from the group consisting of hydrogen, (C1-C2)-alkyl and arylalkyl with less than sixteen carbon atom; A is selected from the group consisting of hydrogen, —SO3H, —SO3M and —COCH3; B is selected from the group consisting of hydrogen, —SO3H, —SO3M and —COCH3, wherein either A or B are necessarily either —SO3H or —SO3M, M being a an organic or metallic cation. Said compounds can be used as anti-arthritic agents, anti-inflammatory agents or to control blood coagulation.
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- Conversion of glucosamine to galactosamine and allosamine derivatives: Control of inversions of stereochemistry at C-3 and C-4
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The reactions of sodium benzoate with a series of trimesylates derived from glucosamine have been examined in an attempt to gain facile access to galactosamine analogues. Trimesylate 17, in which the amino group was protected as a phthalimide, underwent double displacement at positions 4 and 6 to give the dibenzoate 18 with the desired galactosamine configuration. In contrast, trimesylates 21 and 27, in which the amino groups were protected as acetamides, unexpectedly underwent double displacement at positions 3 and 6, giving products 22 and 28, respectively, with allosamine configurations.
- McGeary,Wright,Toth
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p. 5102 - 5105
(2007/10/03)
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- Furanodictine A and B: Amino sugar analogues produced by cellular slime mold Dictyostelium discoideum showing neuronal differentiation activity
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We investigated the constituents of Dictyostelium discoideum to clarify the diversity of secondary metabolites of Dictyostelium cellular slime molds and to explore biologically active substances that could be useful in the development of novel drugs. From a methanol extract of the multicellular fruit body of D. discoideum, we isolated two novel amino sugar analogues, furanodictine A (1) and B (2). They are the first 3,6-anhydrosugars to be isolated from natural sources. Their relative structures were elucidated by spectral means, and the absolute configurations were confirmed by asymmetric syntheses of 1 and 2. These furanodictines potently induce neuronal differentiation of rat pheochromocytoma (PC-12) cells.
- Kikuchi,Saito,Komiya,Takaya,Honma,Nakahata,Ito,Oshima
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p. 6982 - 6987
(2007/10/03)
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- Preparation and Properties of New Surfactants Containing D-Glucosamine as the Building Block
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Three types of new surfactants were prepared by using N-acetyl-D-glucosamine as a starting material.The first type of surfactant, sodium methyl 4,6-O-alkylidene-2-(carboxylatomethylamino)-2-deoxy-D-glucopyranoside, was prepared successively by the following treatments: methyl glucosidation of N-acetyl-D-glucosamine, transacetalization with an appropriate aldehyde dimethyl acetal, deacetylation, and finally reaction of the resulting methyl-4,6-O-alkylidene-2-amino-2-deoxy-D-glucopyranoside (2-amino precursor) with bromoacetic acid.The reaction of this 2-amino precursor with methyl iodide yielded the second type of surfactant, methyl 4,6-O-alkylidene-2-deoxy-2(trimethylammonio)-D-glucopyranoside iodide, in excellent yield.The last type of compound, sodium methyl 2-acetamide-4,6-O-alkylidene-3-O--2-deoxy-D-glucopyranoside, was synthesized by the reaction of methyl 2-acetamide-4,6-O-alkylidene-2-deoxy-D-glucopyranoside with 2-chloropropionic acid.Concerning the two carboxylate types of surfactants, the compounds containing a C9 or C11 hydrophobic chain in the alkylidene part showed higher water solubility than the corresponding compounds containing a C7 hydrophobic chain.Both the micelle-forming property and the ability to lower the surface tension of these carboxylate types of compounds increased with an increase in the length of the hydrophobic chain in the alkylidene part.These compounds can be applied to new acid-decomposable types of cleavable surfactants because they contain an acetal group.The acetal bond of the ammonium type of compound was cleaved more slowly than that of the corresponding carboxylate types of surfactants in 2percent aqueous HCl solution.The biodegradabilities of these compounds were also determined.KEY WORDS: Acetalization, acid decomposition properties, biodegradability, D-glucosamine, surface-active properties.
- Kida, Toshiyuki,Yurugi, Keiji,Masuyama, Araki,Nakatsuji, Yohji,Ono, Daisuke,Takeda, Tokuji
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p. 773 - 780
(2007/10/03)
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- Synthesis of 1D-(1,3,5/2,4)-4-acetamido-5-amino-1,2,3-cyclohexanetriol and its incorporation into a pseudo-disaccharide
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The synthesis of the title compound and 1D-(1,3,5/2,4)-4-acetamido-5-amino-3-O-(β-D-glucopyranosyluronic acid)-1,2,3-cyclohexanetriol is described.Starting from methyl 2-acetamido-2-deoxy-α-D-glucopyranoside 2L-(2,4,5/3)-4-acetamido-3-benzoyloxy-2-benzylo
- Wang, Lai-Xi,Sakairi, Nobuo,Kuzuhara, Hiroyoshi
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