10022-13-6Relevant articles and documents
A facile and stereoselective synthesis of 3,4,6-tri-O-acetyl-2-deoxy-2- phthalimido-β-D-glucopyranosyl chloride
Cao, Zhiling,Liu, Wenjie,Qu, Yingying,Yao, Guowei,Gao, Dachao,Liu, Weiwei
, p. 467 - 469 (2013)
Acetylation of D-glucosamine catalysed by sulfuric acid and N-phthaloylation of the glucosyl acetate yielded 1,3,4,6- tetra-O-acetyl-2- deoxy-2-phthalimido-α-D-glucopyranose. This gave the corresponding pure β-glucosyl chloride upon treatment with PCl5-BF3. An anomeric chlorination with thionyl chloride combined with the Lewis acids (ZnCl2, SnCl4 and BiCl3) resulted in an α/β anomer mixture.
Differently N-protected 3,4,6-tri-O-acetyl-2-amino-2-deoxy-d-glucopyranosyl chlorides and their application in the synthesis of diosgenyl 2-amino-2-deoxy-β-d-glucopyranoside
Bednarczyk, Dorota,Walczewska, Agata,Grzywacz, Daria,Sikorski, Artur,Liberek, Beata,Myszka, Henryk
, p. 10 - 17 (2013)
Four differently N-protected 3,4,6-tri-O-acetyl-2-amino-2-deoxy-d- glucopyranosyl chlorides were synthesized and used as glycosyl donors in reactions with diosgenin. The following amine group protections were tested: trifluoroacetyl (TFA), 2,2,2-trichloroethoxycarbonyl (Troc), phthaloyl (Phth), and tetrachlorophthaloyl (TCP). Products of glycosylation were deprotected to yield diosgenyl 2-amino-2-deoxy-β-d-glucopyranoside. The efficiency of the procedures is discussed. Additionally, a single-crystal X-ray diffraction analysis for 3,4,6-tri-O-acetyl-2-deoxy-2-tetrachlorophthalimido-β-d- glucopyranosyl chloride is reported. Orientations of the pyranose substituents as well as the planarity of the acetoxy and phthalimide groups in the crystal lattice are discussed. Structural evidence is presented for a mesomeric effect in both groups. The preference of the cis over trans orientation of the acetoxy group is confirmed in the crystal lattice.
Enhanced binding to DNA and topoisomerase I inhibition by an analog of the antitumor antibiotic rebeccamycin containing an amino sugar residue
Bailly, Christian,Qu, Xiaogang,Anizon, Fabrice,Prudhomme, Michelle,Riou, Jean-Francois,Chaires, Jonathan B.
, p. 377 - 385 (1999)
Many antitumor agents contain a carbohydrate side chain appended to a DNA-intercalating chromophore. This is the case with anthracyclines such as daunomycin and also with indolocarbazoles including the antibiotic rebeccamycin and its tumor active analog, NB506. In each case, the glycoside residue plays a significant role in the interaction of the drug with the DNA double helix. In this study we show that the DNA-binding affinity and sequence selectivity of a rebeccamycin derivative can be enhanced by replacing the glucose residue with a 2'-aminoglucose moiety. The drug-DNA interactions were studied by thermal denaturation, fluorescence, and footprinting experiments The thermodynamic parameters indicate that the newly introduced amino group on the glycoside residue significantly enhanced binding to DNA by increasing the contribution of the polyelectrolyte effect to the binding free energy, but does not appear to participate in any specific molecular contacts. The energetic contribution of the amino group of the rebeccamycin analog was found to be weaker than that of the sugar amino group of daunomycin, possibly because the indolocarbazole derivative is only partially charged at neutral pH. Topoisomerase I-mediated DNA cleavage studies reveal that the OH→NH2 substitution does not affect the capacity of the drug to stabilize enzyme-DNA covalent complexes. Cytotoxicity studies with P388 leukemia cells sensitive or resistant to camptothecin suggest that topoisomerase I represents a privileged intracellular target for the studied compounds. The role of the sugar amino group is discussed. The study provides useful guidelines for the development of a new generation of indolocarbazole- based antitumor agents.
Structure activity relationships of N-linked and diglycosylated glucosamine-based antitumor glycerolipids
Ogunsina, Makanjuola,Pan, Hangyi,Samadder, Pranati,Arthur, Gilbert,Schweizer, Frank
, p. 15288 - 15304 (2013)
1-O-Hexadecyl-2-O-methyl-3-O-(2′-amino-2′-deoxy-β-D- glucopyranosyl)-snglycerol (1) was previously reported to show potent in vitro antitumor activity on a range of cancer cell lines derived from breast, pancreas and prostate cancer. This compound was not toxic to mice and was inactive against breast tumor xenografts in mice. This inactivity was attributed to hydrolysis of the glycosidic linkage by glycosidases. Here three N-linked (glycosylamide) analogs 2-4, one triazole-linked analog 5 of 1 as well as two diglycosylated analogs 6 and 7 with different stereochemistry at the C2-position of the glycerol moiety were synthesized and their antitumor activity against breast (JIMT-1, BT-474, MDA-MB-231), pancreas (MiaPaCa2) and prostrate (DU145, PC3) cancer cell lines was determined. The diglycosylated analogs 1-O-hexadecyl-2(R)-, 3-O-di-(2′-amino-2′-deoxy- β-D- glucopyranosyl)-sn-glycerol (7) and the 1:1 diastereomeric mixture of 1-O-hexadecyl- 2(R/S), 3-O-di-(2′-amino-2′-deoxy-β-D- glucopyranosyl)-sn-glycerol (6) showed the most potent cytotoxic activity at CC50 values of 17.5 μM against PC3 cell lines. The replacement of the O-glycosidic linkage by a glycosylamide or a glycosyltriazole linkage showed little or no activity at highest concentration tested (30 μM), whereas the replacement of the glycerol moiety by triazole resulted in CC50 values in the range of 20 to 30 μM. In conclusion, the replacement of the O-glycosidic linkage by an N-glycosidic linkage or triazole-linkage resulted in about a two to three fold loss in activity, whereas the replacement of the methoxy group on the glycerol backbone by a second glucosamine moiety did not improve the activity. The stereochemistry at the C2-position of the glycero backbone has minimal effect on the anticancer activities of these diglycosylated analogs.
Direct and efficient monitoring of glycosyltransferase reactions on gold colloidal nanoparticles by using mass spectrometry
Nagahori, Noriko,Nishimura, Shin-Ichiro
, p. 6478 - 6485 (2006)
A simple and efficient assay for glycosyltransferase activity on gold colloidal nanoparticles (GCNPs) by using laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF-MS) is demonstrated by the enzymatic synthesis of the Lewis X trisaccharide on GCNPs containing GlcNAc residues. GCNPs containing multivalent sugars were well dispersed in aqueous solution and proved to be excellent acceptor substrates for the glycosyltransferase reaction. Direct LDI-TOF MS analysis of these GCNPs provided the ion peaks of the sugar derivatives, chemisorbed through S-Au linkages onto the GCNPs, even in the presence of contaminants such as proteins and salts. Thus, it enabled the rapid and direct detection of the enzymatic reaction on the GCNPs by subjecting a small amount (0.15 μL) of the reaction mixture to MS analysis without purification. Subsequent MS/MS analyses (LDI-LIFT-TOF/TOF method) of the product-carrying GCNPs enabled the structures of the sugar derivatives that had been constructed on the GCNPs by enzymatic glycosylation to be determined. A quantitative inhibition assay for glycosyltransferase by using LDI-TOF MS analysis on the GCNPs was demonstrated by using uridine 5′-di-phosphate (UDP) as the inhibitor. This simple assay was then applied to the detection of the enzymatic activity of a crude cell extract of Escherichia coli, which produces Neisseria meningitidis β-1,4-galactosyltransferase (β-1,4-GalT). In this case, the GCNPs were roughly purified by means of ultrafiltration to remove the buffer and detergents before MS analysis. That the GCNPs are dissolved in solution in the reaction medium but are solid in the purification process is greatly advantageous for the simple and efficient detection of enzymatic activity in crude biological samples. Thus, GCNPs containing a variety of biomolecules may become a versatile and efficient tool for the rapid and direct monitoring of metabolism (metabolomics) in living cells when combined with LDI-TOF MS analysis.
Glycoconjugate probes containing a core-fucosylated N-glycan trisaccharide for fucose lectin identification and purification
Cai, Deqin,Xun, Chaochao,Tang, Feng,Tian, Xiaobo,Yang, Liyun,Ding, Kan,Li, Wenzhe,Le, Zhiping,Huang, Wei
, p. 143 - 152 (2017)
Glyco-PAMAM dendrimers and glyco-agarose beads bearing a core-fucosylated N-glycan trisaccharide GlcNAcβ1,4(Fucα1,6)GlcNAc or a non-fucose disaccharide GlcNAcβ1,4GlcNAc were successfully synthesized and characterized by monosaccharide analysis with HPAEC-PAD technique. These glycoconjugates as fucose lectin probes were applied in fucose-specific lectin detection and purification. The model fucose lectin AAL indicated binding activity with the FITC-labeled PAMAM carrying core-fucose trisaccharide. An affinity chromatography column stuffed with the agarose beads carrying core-fucosylated trisaccharide exhibited a good specificity in purification of AAL than non-fucose disaccharide agarose beads. These novel glycoconjugates bearing the precise and simplified core-fucose N-glycan structure provided a potential application for core-fucose-specific lectin discovery.
A practical synthesis of a (1→6)-linked β-D-glucosamine nonasaccharide
Yang, Feng,Du, Yuguo
, p. 495 - 502 (2003)
A (1→6)-β-D-glucosamine nonasaccharide was convergently synthesized using isopropyl thioglycosides as donors. Anomeric acetylated glucosamine derivatives were proved to be good acceptors in the NIS/TMSOTf catalyzed glycosylation. The target nonasaccharide showed a mild antitumor activity against H22 on the preliminary mice tests.
Synthesis and characterization of N-acyl-tetra-O-acyl glucosamine derivatives
Dang, Chi-Hien,Nguyen, Cong-Hao,Nguyen, Thanh-Danh,Im, Chan
, p. 6239 - 6245 (2014)
Novel 1,3,4,6-tetra-O-acyl-N-acyl-d-glucosamine derivatives were synthesized from glucosamine hydrochloride (GlcN·HCl) by the acylation with pyridine as a catalyst. A derivative of tetra-O-acetyl glucosamine contained ketoprofen, a non-steroidal anti-inflammatory drug (NSAID) with analgesic and antipyretic effects, was first synthesized. In analysis of the NMR spectra, the ratio of α:β-anomer showed that penta-acyl-d- glucosamine derivatives and N-acetylated glucosamines containing O-acyl groups have been only the α-anomer. Meanwhile, both the intermediates and the glucoconjugate compound of ketoprofen have only the β-anomer.
Synthesis and immunological evaluation of a low molecular weight saccharide with TLR-4 agonist activity
Basava, Vikram,Romlein, Heather,Bitsaktsis, Constantine,Marzabadi, Cecilia H.
, p. 697 - 705 (2017)
The paucity of FDA approved adjuvants renders the synthesis, characterization, and use of new compounds as vaccine adjuvants, a necessity. For this purpose, a novel saccharide analog has been synthesized from glucosamine, pyruvylated galactose and 1,4-cyclohexanediol and its biological efficacy was determined in innate immune cells. More specifically, we assessed the production of pro-inflammatory cytokines from the murine monocyte cell line, Raw 264.7 and from C57 BL/6 mouse peritoneal macrophages following exposure to the saccharide analog. Our data conclude that the novel saccharide has immunostimulatory activity on mouse macrophages as indicated by the elevated levels of IL-6 and TNF-α in culture supernatants. This effect was TLR-4-dependent but TLR-2-independent. Our data, suggest TLR-4 agonism; a key feature of vaccine adjuvants.
A Fluorescent Transport Assay Enables Studying AmpG Permeases Involved in Peptidoglycan Recycling and Antibiotic Resistance
Perley-Robertson, G. Evan,Yadav, Anuj K.,Winogrodzki, Judith L.,Stubbs, Keith A.,Mark, Brian L.,Vocadlo, David J.
, p. 2626 - 2635 (2016)
Inducible AmpC β-lactamases deactivate a broad-spectrum of β-lactam antibiotics and afford antibiotic resistance in many Gram-negative bacteria. The disturbance of peptidoglycan recycling caused by β-lactam antibiotics leads to accumulation of GlcNAc-1,6-anhydroMurNAc-peptides, which are transported by AmpG to the cytoplasm where they are processed into AmpC inducers. AmpG transporters are poorly understood; however, their loss restores susceptibility toward β-lactam antibiotics, highlighting AmpG as a potential target for resistance-attenuating therapeutics. We prepare a GlcNAc-1,6-anhydroMurNAc-fluorophore conjugate and, using live E. coli spheroplasts, quantitatively analyze its transport by AmpG and inhibition of this process by a competing substrate. Further, we use this transport assay to evaluate the function of two AmpG homologues from Pseudomonas aeruginosa and show that P. aeruginosa AmpG (Pa-AmpG) but not AmpP (Pa-AmpP) transports this probe substrate. We corroborate these results by AmpC induction assays with Pa-AmpG and Pa-AmpP. This fluorescent AmpG probe and spheroplast-based transport assay will enable improved understanding of PG recycling and of permeases from the major facilitator superfamily of transport proteins and may aid in identification of AmpG antagonists that combat AmpC-mediated resistance toward β-lactam antibiotics.
