Carbasugar Analogues of Galactofuranosides: Pseudodisaccharide Mimics of Fragments of Mycobacterial Arabino­galactan

Frigell, Jens; Pearcey, J.; Lowary, Todd L.; Cumpstey, Ian

doi:10.1002/ejoc.201001380

Cited by 18 publications

(18 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Alternatively, if there is a rapid equilibrium between the two reg- ioisomeric activated alcohols (RO 1 -P + Ph 3 and R 0 O 2 -P + Ph 3 ), possibly via a discrete five-membered ring intermediate, 52 before ratedetermining ring-closure, the regioselectivity may be explained by the higher electrophilicity of C-1 than C-2. Bearing in mind our other results on the relative nucleophilicity of OH-1 and OH-2 in 13 (moderate-good regioselectivity with TsCl as electrophile) 22,21 and epoxide-opening of 18 (excellent regioselectivity), the latter explanation seems more likely.…”

Section: Bnomentioning

confidence: 84%

“…50 We tried to open carbafuranose epoxide 18 under basic conditions (NaH, 15-crown-5, DMF, 70-100°C) without success; no reaction was seen with alcohols Rha OH-4 (22) and Man OH-3 (23), even after several days. We then examined the reactivity of the epoxide 18 towards a sulfur nucleophile for the synthesis of carbagalactofuranose C-1 thioethers.…”

Section: Bnomentioning

confidence: 99%

“…Treatment of diol 13 with DIAD and triphenylphosphine resulted in 1,2-epoxide 18, formed as a single diastereomer by intramolecular Mitsunobu type reaction. 22 The stereochemistry of epoxide 18 was apparent as a two-step procedure from diol 13 via an isolated C-1 tosylate gave the same product 18. 22 We investigated the epoxide-opening reaction with simple model alcohol nucleophiles (10 equiv) in the presence of BF 3 ÁEt 2 O as a Lewis acid catalyst (Scheme 5).…”

Section: Bnomentioning

confidence: 99%

“…22 The stereochemistry of epoxide 18 was apparent as a two-step procedure from diol 13 via an isolated C-1 tosylate gave the same product 18. 22 We investigated the epoxide-opening reaction with simple model alcohol nucleophiles (10 equiv) in the presence of BF 3 ÁEt 2 O as a Lewis acid catalyst (Scheme 5). Opening with primary (ethanol), secondary (isopropanol), or tertiary (tert-butanol) alcohols gave the respective ethers 19a-c in high yields.…”

Section: Bnomentioning

confidence: 99%

“…20 Carbadisaccharides containing carba-(hexo or pento)-furanosides do not appear to have been described before. 2,21,22 Considering the scarce results in the carbahexofuranose field and the great biological significance of galactofuranose, both the synthesis and potential biological applications are of interest.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Carbasugar analogues of galactofuranosides: β-O-linked derivatives and towards β-S-linked derivatives

Frigell¹,

Eriksson²,

Cumpstey³

2011

Carbohydrate Research

Self Cite

View full text Add to dashboard Cite

Section: Bnomentioning

confidence: 84%

Section: Bnomentioning

confidence: 99%

Section: Bnomentioning

confidence: 99%

Section: Bnomentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Carbasugar analogues of galactofuranosides: β-O-linked derivatives and towards β-S-linked derivatives

Frigell¹,

Eriksson²,

Cumpstey³

2011

Carbohydrate Research

Self Cite

View full text Add to dashboard Cite

Hybrid Conducting Biofilm with Built‐in Bacteria for High‐Performance Microbial Fuel Cells

Zhao

Ding

et al. 2015

ChemElectroChem

View full text Add to dashboard Cite

Efficiently transportinge xtracellulare lectrons from microbial biofilms to the electrodes is challenging and criticali na chieving high-performance microbial fuel cells (MFCs). In this work, we develop as imple and effective method to fabricate hybrid electroactive biofilms by inserting bacteria into graphenecarbon-nanotube (G-CNT) networks (namely,G -CNT-biofilm) as an anode for MFCs. This novel architecture greatlye nhances direct extracellular electron transfer between Shewanella oneidensis and the electrode, due to strong adhesion of the hybrid conducting biofilm onto the anode surface, as well as the large surface area of graphene and the highc onductivity of CNTs. Ac urrent density of 120 mAcm À2 and am aximum power density of 97.9 mWcm À2 are obtained in the MFC with the hybrid biofilm anode, which is significantly highert han those of an aturallyg rowing biofilm anode (20 mAcm À2 and 6.5 mWcm À2 ).Electroactive microorganisms, organized as as tructured community (as biofilm) grown or enriched at the anode, have potential applicationsi nb ioelectrochemical systems( BESs), such as microbial fuel cells (MFCs)a nd electrolysis cells (ECs). For example,s uch systemsa re employed in energy generation and simultaneous wastewatert reatment. [1] However,t he relatively low power density in such BESs, mainly caused by poor extracellular electron transfer (EET), remains one of the main obstacles for their use in practical applications. [2] Generally,E ET from bacteria to electrode can occur via two mechanisms:1 )outermembrane cytochromes and conductive nanowires, and 2) mediated electron shuttles. [3] It is believed that EET efficiency is one of the key steps in determining the performance of BESs. Thus, how to dramatically enhance the EET is an important topic forBESs.As one family member of BESs, MFCs also employ electroactive microbial biofilms as biocatalysts to oxidizec omplex organic matter and to convert this chemical energy into electrical current. [4] Thus, the biofilm-based anode,s erving as as olid extracellular electron acceptor, has been considered as the heart of the MFC. [5] To emphasizei ts importance,s everal approaches have been explored to improve the properties of anodesf or facilitating EET processes. [6] For example, av ariety of electrode materials with high specific surface areas have been used, including stainless steel foam, three-dimensional (3D) macroporous electrodes and graphene-based materials. [7] Although these materials are desirable for the attachment of bacterialc ells, the number of cells formed on electrode surface remains ab ig challenge. It is thus highly desirable and important to develop simple and efficient strategies for large amountsofb acterial cells to adhere to the anode surface.Herein, we present as imple and effective methodt oc onstruct an ew architecture of highly electroactive hybrid biofilm, which is composed of ag raphene-carbon-nanotube( G-CNT) network with built-in bacteria (denoted as G-CNT-biofilm)a s an anode for MFCs (Scheme 1). Graphene oxide (GO...

show abstract

Synthesis of Unprecedented Sulfonylated Phosphono‐exo‐Glycals Designed as Inhibitors of the Three Mycobacterial Galactofuranose Processing Enzymes

Frédéric

Tikad

et al. 2016

Chemistry A European J

Self Cite

View full text Add to dashboard Cite

This study reports a new methodology to synthesize exo-glycals bearing both a sulfone and a phosphonate. This synthetic strategy provides a way to generate exo-glycals displaying two electron-withdrawing groups and was applied to eight different carbohydrates from the furanose and pyranose series. The Z/E configurations of these tetrasubstituted enol ethers could be ascertained using NMR spectroscopic techniques. Deprotection of an exo-glycal followed by an UMP (uridine monophosphate) coupling generated two new UDP (uridine diphosphate)-galactofuranose analogues. These two Z/E isomers were evaluated as inhibitors of UGM, GlfT1, and GlfT2, the three mycobacterial galactofuranose processing enzymes. Molecule 46-(E) is the first characterized inhibitor of GlfT1 reported to date and was also found to efficiently inhibit UGM in a reversible manner. Interestingly, GlfT2 showed a better affinity for the (Z) isomer. The three enzymes studied in the present work are not only interesting because, mechanistically, they are still the topic of intense investigations, but also because they constitute very important targets for the development of novel antimycobacterial agents.

show abstract

Carbasugar Analogues of Galactofuranosides: Pseudodisaccharide Mimics of Fragments of Mycobacterial Arabinogalactan

Cited by 18 publications

References 31 publications

Carbasugar analogues of galactofuranosides: β-O-linked derivatives and towards β-S-linked derivatives

Carbasugar analogues of galactofuranosides: β-O-linked derivatives and towards β-S-linked derivatives

Hybrid Conducting Biofilm with Built‐in Bacteria for High‐Performance Microbial Fuel Cells

Synthesis of Unprecedented Sulfonylated Phosphono‐exo‐Glycals Designed as Inhibitors of the Three Mycobacterial Galactofuranose Processing Enzymes

Contact Info

Product

Resources

About

Carbasugar Analogues of Galactofuranosides: Pseudodisaccharide Mimics of Fragments of Mycobacterial Arabino­galactan

Cited by 18 publications

References 31 publications

Carbasugar analogues of galactofuranosides: β-O-linked derivatives and towards β-S-linked derivatives

Carbasugar analogues of galactofuranosides: β-O-linked derivatives and towards β-S-linked derivatives

Hybrid Conducting Biofilm with Built‐in Bacteria for High‐Performance Microbial Fuel Cells

Synthesis of Unprecedented Sulfonylated Phosphono‐exo‐Glycals Designed as Inhibitors of the Three Mycobacterial Galactofuranose Processing Enzymes

Contact Info

Product

Resources

About

Carbasugar Analogues of Galactofuranosides: Pseudodisaccharide Mimics of Fragments of Mycobacterial Arabinogalactan