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1.
Mol Cell ; 84(16): 3115-3127.e11, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39116872

RESUMO

Proteasome is essential for cell survival, and proteasome inhibition induces proteasomal gene transcription via the activated endoplasmic-reticulum-associated transcription factor nuclear factor erythroid 2-like 1 (Nrf1/NFE2L1). Nrf1 activation requires proteolytic cleavage by DDI2 and N-glycan removal by NGLY1. We previously showed that Nrf1 ubiquitination by SKP1-CUL1-F-box (SCF)FBS2/FBXO6, an N-glycan-recognizing E3 ubiquitin ligase, impairs its activation, although the molecular mechanism remained elusive. Here, we show that SCFFBS2 cooperates with the RING-between-RING (RBR)-type E3 ligase ARIH1 to ubiquitinate Nrf1 through oxyester bonds in human cells. Endo-ß-N-acetylglucosaminidase (ENGASE) generates asparagine-linked N-acetyl glucosamine (N-GlcNAc) residues from N-glycans, and N-GlcNAc residues on Nrf1 served as acceptor sites for SCFFBS2-ARIH1-mediated ubiquitination. We reconstituted the polyubiquitination of N-GlcNAc and serine/threonine residues on glycopeptides and found that the RBR-specific E2 enzyme UBE2L3 is required for the assembly of atypical ubiquitin chains on Nrf1. The atypical ubiquitin chains inhibited DDI2-mediated activation. The present results identify an unconventional ubiquitination pathway that inhibits Nrf1 activation.


Assuntos
Fator 1 Nuclear Respiratório , Ubiquitinação , Humanos , Células HEK293 , Fator 1 Nuclear Respiratório/metabolismo , Fator 1 Nuclear Respiratório/genética , Fator 1 Relacionado a NF-E2/metabolismo , Fator 1 Relacionado a NF-E2/genética , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Acetilglucosamina/metabolismo , Células HeLa , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas F-Box/metabolismo , Proteínas F-Box/genética
2.
Bioorg Med Chem ; 100: 117612, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38290307

RESUMO

A fluorescence-quenching-based assay system was constructed to determine the hydrolytic activity of endo-ß-N-acetylglucosaminidases (ENGases) interacting with hybrid-type N-glycans. This was achieved using a dual-labeled fluorescent probe with a nonasaccharide structure. We produced the nonasaccharide skeleton by the stepwise glycosylation of the galactose residue on a galactosyl chitobiose derivative. Next, we introduced azido and acetoxy groups into the nonasaccharide derivative in a stepwise manner, which led to stereochemistry inversion at both the C-4 and C-2 hydroxy groups on its galactose residue. The protecting groups of the resulting nonasaccharide derivative were removed, and the derivative was labeled with an N-methylanthraniloyl group to obtain a reporter dye and a 2,4-dinitrophenyl group as a quenching molecule to obtain target probe 1. The use of this probe along with a microplate reader enabled a facile evaluation of the hydrolytic activities of ENGases Endo-H, Endo-M, Endo-F3, Endo-S, and Endo-CC. Furthermore, this probe could also assist in the search for novel ENGases that are specific to hybrid-type N-glycans.


Assuntos
Acetilglucosaminidase , Corantes Fluorescentes , Corantes Fluorescentes/química , Acetilglucosaminidase/química , Galactose , Polissacarídeos/química , Glicosilação , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/metabolismo
3.
Org Biomol Chem ; 21(10): 2138-2142, 2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36794702

RESUMO

The glycosylation of unprotected carbohydrates has emerged as an area of significant interest because it obviates the need for long reaction sequences involving protecting-group manipulations. Herein, we report the one-pot synthesis of anomeric glycosyl phosphates through the condensation of unprotected carbohydrates with phospholipid derivatives while retaining high stereo- and regioselective control. The anomeric center was activated using 2-chloro-1,3-dimethylimidazolinium chloride to facilitate condensation with glycerol-3-phosphate derivatives in an aqueous solution. A water/propionitrile mixture provided superior stereoselectivity while maintaining good yields. Under these optimized conditions, the condensation of stable isotope-labeled glucose with phosphatidic acid provided efficient access to labeled glycophospholipids as an internal standard for mass spectrometry.

4.
Glycobiology ; 32(4): 314-332, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-34939097

RESUMO

Recent studies demonstrated the occurrence of sialyl free N-glycans (FNGs) in sera from a variety of animals. Unlike the intracellular FNGs that mainly carry a single N-acetylglucosamine at their reducing termini (Gn1-type), these extracellular FNGs have an N,N'-diacetylchitobiose at their reducing termini (Gn2-type). The detailed mechanism for how they are formed, however, remains unclarified. In this study, we report on an improved method for isolating FNGs from sera and found that, not only sialyl FNGs, but also neutral FNGs are present in animal sera. Most of the neutral oligomannose-type FNGs were found to be Gn1-type. We also found that a small portion of sialyl FNGs were Gn1-type. The ratio of Gn1-type sialyl FNGs varies between species, and appears to be partially correlated with the distribution of lysosomal chitobiase activity. We also identified small sialylated glycans similar to milk oligosaccharides, such as sialyl lactose or sialyl N-acetyllactosamine in sera. Our results indicate that there are varieties of free oligosaccharides in sera and the mechanism responsible for their formation is more complicated than currently envisaged.


Assuntos
Oligossacarídeos , Polissacarídeos , Acetilglucosamina , Animais , Citosol
5.
Bioorg Med Chem Lett ; 52: 128391, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34601028

RESUMO

Sulfoquynovosylacyl propanediol (SQAP; 1) has been developed as a radiosensitizer (anti-cancer agent) for solid tumors, but it was easily cleaved in vivo and had a problem of short residence time. We synthesized a novel compound of a SQAP derivative (3-octadecanoxypropyl 6-deoxy-6-sulfo-α-d-glucopyranoside: ODSG; 2) to solve these problems not easily cleaved by lipase. ODSG (2) cytotoxicity was investigated in vitro, resulting in low toxicity like SQAP (1).


Assuntos
Lipase/metabolismo , Radiossensibilizantes/farmacologia , Células A549 , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Radiossensibilizantes/química , Radiossensibilizantes/metabolismo , Relação Estrutura-Atividade
6.
Bioorg Med Chem Lett ; 29(13): 1643-1646, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31076349

RESUMO

We synthesized a fluorogenic probe with a high-mannose type heptasaccharide structure to detect the hydrolytic activity of endo-ß-N-acetylglucosaminidase from Streptomyces plicatus (Endo-H). The heptasaccharide derivative (1) was labeled with an N-methylanthraniloyl group as a reporter dye at the branching point of the ß-mannoside residue and 2,4-dinitrophenyl group as a quencher molecule at the reducing end, which was hydrolyzed by Endo-H, resulting in increased fluorescence intensity. Thus, Endo-H activities could be evaluated easily and quantitatively by measuring the fluorescence signal. Using both this probe (1) and a previously synthesized pentasaccharide probe, the hydrolysis activity of Endo-H and Endo-M were investigated. The results clearly showed a correlation with the substrate specificity of each enzyme.


Assuntos
Corantes Fluorescentes/uso terapêutico , Manose/metabolismo , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/metabolismo , Corantes Fluorescentes/farmacologia
7.
Chembiochem ; 19(2): 136-141, 2018 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-29125207

RESUMO

To demonstrate the structural specificity of the glycosyl donor for the transglycosylation reaction by using endo-ß-N-acetylglucosaminidase from Mucor hiemalis (endo-M), a series of tetrasaccharide oxazoline derivatives was synthesized. These derivatives correspond to the core structure of an asparagine-linked glycoprotein glycan with a ß-mannose unit of a non-natural-type monosaccharide, including ß-glucose, ß-galactose, and ß-talose in place of the ß-mannose moiety. The transglycosylation activity of wildtype (WT) endo-M and two mutants, N175Q and N175A, was examined by using these tetrasaccharide donors with p-nitrophenyl N-acetylglucosaminide (GlcNAc-pNp). The essential configuration of the hydroxy group for the transglycosylation reaction was determined. On the basis of these results, the transglycosylation reaction was investigated by using chemically modified donors, and transglycosylated products were successfully obtained.


Assuntos
Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/metabolismo , Oligossacarídeos/biossíntese , Oxazóis/metabolismo , Biocatálise , Glicosilação , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/química , Estrutura Molecular , Mucor/enzimologia , Oligossacarídeos/química , Oxazóis/química , Conformação Proteica
8.
Chembiochem ; 19(7): 660-663, 2018 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-29323460

RESUMO

We developed a fluorescence-quenching-based assay system to determine the hydrolysis activity of endo-ß-N-acetylglucosaminidases (ENGases). The pentasaccharide derivative 1 was labeled with an N-methylanthraniloyl group as a reporter dye at the non-reducing end and with a 2,4-dinitrophenyl group as a quencher molecule at the reducing end. This derivative is hydrolyzed by ENGase, resulting in an increase in fluorescence intensity. Thus, the fluorescence signal is directly proportional to the amount of the tetrasaccharide derivative, hence allowing ENGase activity to be evaluated easily and quantitatively. Using this system, we succeeded in measuring the hydrolysis activities of ENGases and thus the inhibitory activities of known inhibitors. We confirmed that this assay system is suitable for high-throughput screening for potential inhibitors of human ENGase that might serve as therapeutic agents for the treatment of N-glycanase 1 (NGLY1) deficiency.


Assuntos
Acetilglucosaminidase/química , Ensaios Enzimáticos/métodos , Corantes Fluorescentes/química , Oligossacarídeos/química , Compostos de Anilina/síntese química , Compostos de Anilina/química , Animais , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/síntese química , Humanos , Hidrólise , Camundongos , Oligossacarídeos/síntese química , Raios Ultravioleta , ortoaminobenzoatos/síntese química , ortoaminobenzoatos/química , ortoaminobenzoatos/efeitos da radiação
9.
Appl Microbiol Biotechnol ; 102(5): 2191-2201, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29332217

RESUMO

Cellulose in plant cell walls is mainly covered by hemicellulose and lignin, and thus efficient removal of these components is thought to be a key step in the optimal utilization of lignocellulose. The recently discovered carbohydrate esterase (CE) 15 family of glucuronoyl esterases (GEs) which cleave the linkages between the free carboxyl group of D-glucuronic acid in hemicellulose and the benzyl groups in lignin residues could contribute to this process. Herein, we report the identification, functional expression, and enzymatic characterization of a GE, AfGE, from the filamentous fungus Aspergillus fumigatus. AfGE was heterologously expressed in Aspergillus oryzae, and the purified enzyme displayed the ability to degrade the synthetic substrates mimicking the ester linkage between hemicellulose and lignin. AfGE is a potentially industrially applicable enzyme due to its characteristic as a thermophilic enzyme with the favorable temperature of 40-50 °C at pH 5. Molecular modeling and site-directed mutagenesis studies of AfGE demonstrated that Lys209 plays an important role in the preference for the substrates containing 4-O-methyl group in the glucopyranose ring.


Assuntos
Aspergillus fumigatus/enzimologia , Esterases/metabolismo , Ésteres/metabolismo , Proteínas Fúngicas/química , Aspergillus fumigatus/química , Aspergillus fumigatus/genética , Aspergillus fumigatus/metabolismo , Estabilidade Enzimática , Esterases/química , Esterases/genética , Esterases/isolamento & purificação , Ésteres/química , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Ácido Glucurônico/metabolismo , Estrutura Molecular , Polissacarídeos/metabolismo , Especificidade por Substrato
10.
Chem Pharm Bull (Tokyo) ; 65(5): 432-441, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28458365

RESUMO

Lubricants are essential additives in tablet formulations. Magnesium stearate (Mg-St) is the most commonly used lubricant in tableting. Here, we used sucrose fatty acid ester (SE) as an additive to manufacture tablets by direct compression. We evaluated the effects of hydrophile-lipophile balance (HLB) and the amount of SE on the flowability of a pharmaceutical powder using angle of repose and practical angle of internal friction measurements. In addition, we investigated the effects of SE on tablet properties. When SEs with an HLB ≥3 were added, the angle of repose was approximately the same as that of a pharmaceutical powder containing Mg-St, with no major differences in flowability. However, the practical angle of internal friction became closer to pharmaceutical powder containing Mg-St as HLB decreased. As HLB increased, the practical angle of internal friction approached the value of additive-free pharmaceutical powder. Tablets containing 2.0% Mg-St had a mean hardness of 40 N and disintegrated in approximately 6 min, whereas tablets containing 2.0% SE (low HLB) had a mean hardness of approximately ≥80 N and disintegrated within 3 min. The results indicate that SEs can be used as lubricants in tablet production by direct compression and to reduce problems associated with the use of Mg-St. In particular, we suggest that SEs with low HLB values can be used as excipients to achieve high tablet hardness and short disintegration time.


Assuntos
Ésteres/química , Ácidos Graxos/química , Lubrificantes/química , Sacarose/química , Comprimidos/química
11.
Biosci Biotechnol Biochem ; 80(1): 128-34, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26613404

RESUMO

Manα1 → 2Man, Manα1 → 3Man, Manα1 → 4Man, and Manα1 → 6Man were converted to the glycosylamine derivatives. Then, they were mixed with monobenzyl succinic acid to obtain their amide derivatives. After removing the benzyl group by hydrogenation, the succinylamide derivatives were coupled with the hydrazino groups on BlotGlyco™ beads in the presence of water-soluble carbodiimide. d-Mannobiose-linked beads were incubated with fluorescence-labeled Escherichia coli with type 1 fimbria, and the number of the fluorescent dots associated with the beads was counted in order to determine the binding preference among d-mannobiose isomers. The results showed that the bacteria bind strongly to Manα1 → 2Man1 → beads, Manα1 → 3Man1 → beads, Manα1 → 4Man1 → beads, and Manα1 → 6Man1 → beads, in order. In the presence of 0.1 M methyl α-d-mannopyranoside, most of the bacteria failed to bind to these beads. These results indicate that E. coli with type 1 fimbria binds to all types of d-mannobiose isomers but preferentially to Manα1 → 2Man disaccharide.


Assuntos
Aderência Bacteriana/fisiologia , Escherichia coli/metabolismo , Fímbrias Bacterianas/metabolismo , Mananas/química , Manose/química , Carbodi-Imidas/química , Configuração de Carboidratos , Escherichia coli/química , Fímbrias Bacterianas/química , Corantes Fluorescentes/química , Hidrogenação , Mananas/metabolismo , Manose/metabolismo , Microesferas , Estereoisomerismo , Succinatos/química
12.
Carbohydr Res ; 536: 109024, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38215662

RESUMO

Chemo-enzymatic glycan engineering is considered to be one of the most promising strategies to enhance efficiency in pharmaceutical research. However, it is assumed that this technology has limited industrial application for the production of biological therapeutics because of the high cost of the process. In this study, we developed a scheme for rapidly preparing a glycan oxazoline and a homogeneously glycosylated antibody. The enzyme-immobilized monolith and the flow chemistry-based approach enabled a glycan oxazoline and a homogeneously glycosylated antibody to be obtained at the gram scale from starting materials (sialylglycopeptide and heterogeneously glycosylated protein) within 2.5 h. This cost-effective scheme for obtaining a large amount of glycan donors and homogeneously glycosylated proteins in a short time will be helpful to implement glycan engineering technology for industrial purposes such as pharmaceutical production.


Assuntos
Anticorpos , Polissacarídeos , Polissacarídeos/metabolismo , Glicosilação
13.
FEBS Lett ; 598(18): 2259-2268, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39171510

RESUMO

The cytosolic peptide:N-glycanase (PNGase) is involved in the quality control of N-glycoproteins via the endoplasmic reticulum-associated degradation (ERAD) pathway. Mutations in the gene encoding cytosolic PNGase (NGLY1 in humans) cause NGLY1 deficiency. Recent findings indicate that the F-box protein FBS2 of the SCFFBS2 ubiquitin ligase complex can be a promising drug target for NGLY1 deficiency. Here, we determined the crystal structure of bovine FBS2 complexed with the adaptor protein SKP1 and a sugar ligand, Man3GlcNAc2, which corresponds to the core pentasaccharide of N-glycan. Our crystallographic data together with NMR data revealed the structural basis of disparate sugar-binding specificities in homologous FBS proteins and identified a potential druggable pocket for in silico docking studies. Our results provide a potential basis for the development of selective inhibitors against FBS2 in NGLY1 deficiency.


Assuntos
Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase , Animais , Bovinos , Humanos , Sequência de Aminoácidos , Sítios de Ligação , Cristalografia por Raios X , Proteínas F-Box/metabolismo , Proteínas F-Box/química , Proteínas F-Box/genética , Modelos Moleculares , Simulação de Acoplamento Molecular , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/metabolismo , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/genética , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase/química , Ligação Proteica
14.
Photodiagnosis Photodyn Ther ; 45: 103898, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38008301

RESUMO

We synthesized a new silyl porphyrin derivative conjugated with 6-deoxy-6-sulfo-α-d-glucopyranose (SGlc). Conjugation with SGlc improved A549 cellular uptake without significant changes in the photophysical and photochemical properties and subcellular localization. This improved cellular uptake led to enhanced photodynamic activity. Furthermore, conjugation with SGlc suppressed dark toxicity. These advantages were not observed for a conjugate with a glucose molecule. These results indicated that the conjugation with SGlc is a promising strategy for enhancing photodynamic efficacy.


Assuntos
Fotoquimioterapia , Porfirinas , Humanos , Fármacos Fotossensibilizantes/farmacologia , Fotoquimioterapia/métodos , Células A549 , Glucose , Porfirinas/farmacologia
15.
Methods Mol Biol ; 2613: 73-78, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36587071

RESUMO

1-stearoyl (18:0)-2-arachidoyl (20:0)-sn-glycero-3-phospho-ß-D-glucoside (Phosphatidylglucoside or PtdGlc) was synthesized by direct coupling of D-glucose with the phosphate group of phosphatidic acid (18:0, 20:0). Selective in situ activation of the anomeric center of D-glucose by 2-chloro-1,3-dimethylimidazolinium chloride (DMC) in aqueous media allows the omission of protecting groups while furnishing the required ß-phosphate linkage with high selectivity. The described method is suitable to access PtdGlc in mg scale utilizing a simple two step purification protocol.


Assuntos
Glucose , Glicerofosfolipídeos , Glucosídeos
16.
Carbohydr Res ; 525: 108764, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36812846

RESUMO

Oligomannose-type glycans on glycoproteins are important signaling molecules in the glycoprotein quality control system in the endoplasmic reticulum. Recently, free oligomannose-type glycans generated by the hydrolysis of glycoproteins or dolichol pyrophosphate-linked oligosaccharides were recognized as important signals for immunogenicity. Hence, there is a high demand for pure oligomannose-type glycans for biochemical experiments; however, the chemical synthesis of glycans to achieve high-concentration products is laborious. In this study, we demonstrate a simple and efficient synthetic strategy for oligomannose-type glycans. Sequential regioselective α-mannosylation at the C-3 and C-6 positions of 2,3,4,6-unprotected galactose residues in galactosylchitobiose derivatives was demonstrated. Subsequently, the inversion of the configuration of the two hydroxy groups at the C-2 and C-4 positions of the galactose moiety was successfully carried out. This synthetic route reduces the number of the protection-deprotection reactions and is suitable for constructing different branching patterns of oligomannose-type glycans, such as M9, M5A, and M5B.


Assuntos
Galactose , Polissacarídeos , Polissacarídeos/química , Glicoproteínas/metabolismo , Glicosilação , Oligossacarídeos/química
17.
Carbohydr Res ; 523: 108724, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36435009

RESUMO

A fluorescence-quenching-based assay system to determine the hydrolytic activity of endo-ß-N-acetylglucosaminidases (ENGases), which act on the innermost N-acetylglucosamine (GlcNAc) residue of the chitobiose segment of core-fucosylated N-glycans, was constructed using a dual-labeled fluorescent probe with a hexasaccharide structure. The fluorogenic probe was evaluated using a variety of ENGases, including Endo-M W251N mutant, Endo-F3, and Endo-S, which recognize core fucosylated N-glycans. The occurrence of a hydrolysis reaction was detected by observing an increased fluorescence intensity, ultimately allowing the ENGase activities to be easily and quantitatively evaluated, with the exception of Endo-S. The obtained results clearly indicated the substrate specificities of the examined ENGases.


Assuntos
Polissacarídeos , Polissacarídeos/química , Glicosilação , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/química , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/metabolismo , Especificidade por Substrato
18.
Pediatr Surg Int ; 28(8): 847-50, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22885807

RESUMO

We describe a modified endoscopic injection technique for the treatment of vesicoureteral reflux (VUR). Our modification combines the STING and proximal HIT injection techniques and results in higher success rates in the resolution in VUR.


Assuntos
Dextranos/administração & dosagem , Ácido Hialurônico/administração & dosagem , Injeções/métodos , Refluxo Vesicoureteral/cirurgia , Refluxo Vesicoureteral/terapia , Endoscopia , Humanos , Resultado do Tratamento , Ureter
19.
Chem Commun (Camb) ; 58(95): 13282-13285, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36373598

RESUMO

A split intein-based method has been developed to detect peptide:N-glycanase (PNGase) activity in live cells. PNGase cleaves the linkage between N,N'-diacetylchitobiose and the Asn side-chain of N-intein peptides and the products react rapidly with C-intein by protein trans-splicing to generate an active luciferase.


Assuntos
Inteínas , Luminescência , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase , Processamento de Proteína , Peptídeos
20.
Carbohydr Res ; 494: 108072, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32563100

RESUMO

An α(1,2)-linked oligomannoside derivative having a free C-2 hydroxyl group and a C-3 pivaloyl group was synthesized from a thiophenyl mannose derivative 1 using a one-pot self-condensation and applying a α-stereoselective procedure. The mannosylation exclusively generated α-mannoside linkages. The observed α-directing effect was rationalized by the remote participation of the pivaloyl group in C-3 position. The polymerization degree was controlled by the promoter amount providing the mannobiose derivative as a major product. Applying this method eliminated many synthetic steps. The α(1,2)-linked oligomannoside derivatives, which are key intermediates for the synthesis of oligomannose type N-glycans for glycoproteins, were easily prepared.


Assuntos
Oligossacarídeos/síntese química , Configuração de Carboidratos , Glicosilação , Oligossacarídeos/química
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