1
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Remmerswaal W, Elferink H, Houthuijs KJ, Hansen T, ter Braak F, Berden G, van der Vorm S, Martens J, Oomens J, van der Marel GA, Boltje TJ, Codée JDC. Anomeric Triflates versus Dioxanium Ions: Different Product-Forming Intermediates from 3-Acyl Benzylidene Mannosyl and Glucosyl Donors. J Org Chem 2024; 89:1618-1625. [PMID: 38235652 PMCID: PMC10845153 DOI: 10.1021/acs.joc.3c02262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2023] [Revised: 12/19/2023] [Accepted: 12/28/2023] [Indexed: 01/19/2024]
Abstract
Minimal structural differences in the structure of glycosyl donors can have a tremendous impact on their reactivity and the stereochemical outcome of their glycosylation reactions. Here, we used a combination of systematic glycosylation reactions, the characterization of potential reactive intermediates, and in-depth computational studies to study the disparate behavior of glycosylation systems involving benzylidene glucosyl and mannosyl donors. While these systems have been studied extensively, no satisfactory explanations are available for the differences observed between the 3-O-benzyl/benzoyl mannose and glucose donor systems. The potential energy surfaces of the different reaction pathways available for these donors provide an explanation for the contrasting behavior of seemingly very similar systems. Evidence has been provided for the intermediacy of benzylidene mannosyl 1,3-dioxanium ions, while the formation of the analogous 1,3-glucosyl dioxanium ions is thwarted by a prohibitively strong flagpole interaction of the C-2-O-benzyl group with the C-5 proton in moving toward the transition state, in which the glucose ring adopts a B2,5-conformation. This study provides an explanation for the intermediacy of 1,3-dioxanium ions in the mannosyl system and an answer to why these do not form from analogous glucosyl donors.
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Affiliation(s)
- Wouter
A. Remmerswaal
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2300 RA, The Netherlands
| | - Hidde Elferink
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen 6525 AJ, The Netherlands
| | - Kas J. Houthuijs
- Institute
for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, Nijmegen 6525 ED, The Netherlands
| | - Thomas Hansen
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2300 RA, The Netherlands
- Department
of Chemistry and Pharmaceutical Sciences, Amsterdam Institute of Molecular
and Life Sciences (AIMMS), Vrije Universiteit
Amsterdam, De Boelelaan
1108, Amsterdam 1081 HZ, The Netherlands
| | - Floor ter Braak
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen 6525 AJ, The Netherlands
| | - Giel Berden
- Institute
for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, Nijmegen 6525 ED, The Netherlands
| | - Stefan van der Vorm
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2300 RA, The Netherlands
| | - Jonathan Martens
- Institute
for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, Nijmegen 6525 ED, The Netherlands
| | - Jos Oomens
- Institute
for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, Nijmegen 6525 ED, The Netherlands
| | | | - Thomas J. Boltje
- Institute
for Molecules and Materials, Radboud University, Heyendaalseweg 135, Nijmegen 6525 AJ, The Netherlands
| | - Jeroen D. C. Codée
- Leiden
Institute of Chemistry, Leiden University, Einsteinweg 55, Leiden 2300 RA, The Netherlands
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2
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de Kleijne FFJ, Ter Braak F, Piperoudis D, Moons PH, Moons SJ, Elferink H, White PB, Boltje TJ. Detection and Characterization of Rapidly Equilibrating Glycosylation Reaction Intermediates Using Exchange NMR. J Am Chem Soc 2023; 145:26190-26201. [PMID: 38008912 DOI: 10.1021/jacs.3c08709] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2023]
Abstract
The stereoselective introduction of glycosidic bonds (glycosylation) is one of the main challenges in the chemical synthesis of carbohydrates. Glycosylation reaction mechanisms are difficult to control because, in many cases, the exact reactive species driving product formation cannot be detected and the product outcome cannot be explained by the primary reaction intermediate observed. In these cases, reactions are expected to take place via other low-abundance reaction intermediates that are in rapid equilibrium with the primary reaction intermediate via a Curtin-Hammett scenario. Despite this principle being well-known in organic synthesis, mechanistic studies investigating this model in glycosylation reactions are complicated by the challenge of detecting the extremely short-lived reactive species responsible for product formation. Herein, we report the utilization of the chemical equilibrium between low-abundance reaction intermediates and the stable, readily observed α-glycosyl triflate intermediate in order to infer the structure of the former species by employing exchange NMR. Using this technique, we enabled the detection of reaction intermediates such as β-glycosyl triflates and glycosyl dioxanium ions. This demonstrates the power of exchange NMR to unravel reaction mechanisms as we aim to build a catalog of kinetic parameters, allowing for the understanding and eventual prediction of glycosylation reactions.
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Affiliation(s)
- Frank F J de Kleijne
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Floor Ter Braak
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Dimitrios Piperoudis
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Peter H Moons
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Sam J Moons
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Hidde Elferink
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Paul B White
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
| | - Thomas J Boltje
- Institute for Molecules and Materials (IMM), Synthetic Organic Chemistry, Radboud University, 6525 AJ Nijmegen, The Netherlands
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3
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Elferink H, Remmerswaal WA, Houthuijs KJ, Jansen O, Hansen T, Rijs AM, Berden G, Martens J, Oomens J, Codée JDC, Boltje TJ. Competing C-4 and C-5-Acyl Stabilization of Uronic Acid Glycosyl Cations. Chemistry 2022; 28:e202201724. [PMID: 35959853 PMCID: PMC9825916 DOI: 10.1002/chem.202201724] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2022] [Indexed: 01/11/2023]
Abstract
Uronic acids are carbohydrates carrying a terminal carboxylic acid and have a unique reactivity in stereoselective glycosylation reactions. Herein, the competing intramolecular stabilization of uronic acid cations by the C-5 carboxylic acid or the C-4 acetyl group was studied with infrared ion spectroscopy (IRIS). IRIS reveals that a mixture of bridged ions is formed, in which the mixture is driven towards the C-1,C-5 dioxolanium ion when the C-5,C-2-relationship is cis, and towards the formation of the C-1,C-4 dioxepanium ion when this relation is trans. Isomer-population analysis and interconversion barrier computations show that the two bridged structures are not in dynamic equilibrium and that their ratio parallels the density functional theory computed stability of the structures. These studies reveal how the intrinsic interplay of the different functional groups influences the formation of the different regioisomeric products.
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Affiliation(s)
- Hidde Elferink
- Institute for Molecules and MaterialsSynthetic Organic ChemistryRadboud University NijmegenHeyendaalseweg 1356525 AJNijmegen (TheNetherlands
| | - Wouter A. Remmerswaal
- Leiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeiden (TheNetherlands
| | - Kas J. Houthuijs
- Institute for Molecules and MaterialsFELIX LaboratoryRadboud University NijmegenToernooiveld 76525 EDNijmegen (TheNetherlands
| | - Oscar Jansen
- Institute for Molecules and MaterialsFELIX LaboratoryRadboud University NijmegenToernooiveld 76525 EDNijmegen (TheNetherlands
| | - Thomas Hansen
- Leiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeiden (TheNetherlands,Departament de Química Inorgànica i Orgànica & IQTUBUniversitat de Barcelona08028BarcelonaSpain
| | - Anouk M. Rijs
- Institute for Molecules and MaterialsFELIX LaboratoryRadboud University NijmegenToernooiveld 76525 EDNijmegen (TheNetherlands,Division of BioAnalytical ChemistryDepartment of Chemistry and Pharmaceutical SciencesAIMMS Amsterdam Institute of Molecular and Life SciencesVrije Univeristeit AmsterdamDe Boelelaan 10851081 HVAmsterdam (TheNetherlands
| | - Giel Berden
- Institute for Molecules and MaterialsFELIX LaboratoryRadboud University NijmegenToernooiveld 76525 EDNijmegen (TheNetherlands
| | - Jonathan Martens
- Institute for Molecules and MaterialsFELIX LaboratoryRadboud University NijmegenToernooiveld 76525 EDNijmegen (TheNetherlands
| | - Jos Oomens
- Institute for Molecules and MaterialsFELIX LaboratoryRadboud University NijmegenToernooiveld 76525 EDNijmegen (TheNetherlands
| | - Jeroen D. C. Codée
- Leiden Institute of ChemistryLeiden UniversityEinsteinweg 552333 CCLeiden (TheNetherlands
| | - Thomas J. Boltje
- Institute for Molecules and MaterialsSynthetic Organic ChemistryRadboud University NijmegenHeyendaalseweg 1356525 AJNijmegen (TheNetherlands
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4
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Remmerswaal WA, Houthuijs KJ, van de Ven R, Elferink H, Hansen T, Berden G, Overkleeft HS, van der Marel GA, Rutjes FPJT, Filippov DV, Boltje TJ, Martens J, Oomens J, Codée JDC. Stabilization of Glucosyl Dioxolenium Ions by "Dual Participation" of the 2,2-Dimethyl-2-( ortho-nitrophenyl)acetyl (DMNPA) Protection Group for 1,2- cis-Glucosylation. J Org Chem 2022; 87:9139-9147. [PMID: 35748115 PMCID: PMC9295149 DOI: 10.1021/acs.joc.2c00808] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
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The stereoselective
introduction of glycosidic bonds is of paramount
importance to oligosaccharide synthesis. Among the various chemical
strategies to steer stereoselectivity, participation by either neighboring
or distal acyl groups is used particularly often. Recently, the use
of the 2,2-dimethyl-2-(ortho-nitrophenyl)acetyl (DMNPA)
protection group was shown to offer enhanced stereoselective steering
compared to other acyl groups. Here, we investigate the origin of
the stereoselectivity induced by the DMNPA group through systematic
glycosylation reactions and infrared ion spectroscopy (IRIS) combined
with techniques such as isotopic labeling of the anomeric center and
isomer population analysis. Our study indicates that the origin of
the DMNPA stereoselectivity does not lie in the direct participation
of the nitro moiety but in the formation of a dioxolenium ion that
is strongly stabilized by the nitro group.
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Affiliation(s)
- Wouter A Remmerswaal
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Kas J Houthuijs
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Roel van de Ven
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Hidde Elferink
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Thomas Hansen
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands.,Departament de Química Inorgànica i Orgànica & IQTUB, Universitat de Barcelona, 08028 Barcelona, Spain
| | - Giel Berden
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Herman S Overkleeft
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Gijsbert A van der Marel
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Floris P J T Rutjes
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Dmitri V Filippov
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
| | - Thomas J Boltje
- Institute for Molecules and Materials, Radboud University, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Jonathan Martens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Jos Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Jeroen D C Codée
- Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333 CC Leiden, The Netherlands
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5
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Braak FT, Elferink H, Houthuijs KJ, Oomens J, Martens J, Boltje TJ. Characterization of Elusive Reaction Intermediates Using Infrared Ion Spectroscopy: Application to the Experimental Characterization of Glycosyl Cations. Acc Chem Res 2022; 55:1669-1679. [PMID: 35616920 PMCID: PMC9219114 DOI: 10.1021/acs.accounts.2c00040] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
![]()
A detailed
understanding of the reaction mechanism(s) leading to
stereoselective product formation is crucial to understanding and
predicting product formation and driving the development of new synthetic
methodology. One way to improve our understanding of reaction mechanisms
is to characterize the reaction intermediates involved in product
formation. Because these intermediates are reactive, they are often
unstable and therefore difficult to characterize using experimental
techniques. For example, glycosylation reactions are critical steps
in the chemical synthesis of oligosaccharides and need to be stereoselective
to provide the desired α- or β-diastereomer. It remains
challenging to predict and control the stereochemical outcome of glycosylation
reactions, and their reaction mechanisms remain a hotly debated topic.
In most cases, glycosylation reactions take place via reaction mechanisms
in the continuum between SN1- and SN2-like pathways.
SN2-like pathways proceeding via the displacement of a
contact ion pair are relatively well understood because the reaction
intermediates involved can be characterized by low-temperature NMR
spectroscopy. In contrast, the SN1-like pathways proceeding
via the solvent-separated ion pair, also known as the glycosyl cation,
are poorly understood. SN1-like pathways are more challenging
to investigate because the glycosyl cation intermediates involved
are highly reactive. The highly reactive nature of glycosyl cations
complicates their characterization because they have a short lifetime
and rapidly equilibrate with the corresponding contact ion pair. To
overcome this hurdle and enable the study of glycosyl cation stability
and structure, they can be generated in a mass spectrometer in the
absence of a solvent and counterion in the gas phase. The ease of
formation, stability, and fragmentation of glycosyl cations have been
studied using mass spectrometry (MS). However, MS alone provides little
information about the structure of glycosyl cations. By combining
mass spectrometry (MS) with infrared ion spectroscopy (IRIS), the
determination of the gas-phase structures of glycosyl cations has
been achieved. IRIS enables the recording of gas-phase infrared spectra
of glycosyl cations, which can be assigned by matching to reference
spectra predicted from quantum chemically calculated vibrational spectra.
Here, we review the experimental setups that enable IRIS of glycosyl
cations and discuss the various glycosyl cations that have been characterized
to date. The structure of glycosyl cations depends on the relative
configuration and structure of the monosaccharide substituents, which
can influence the structure through both steric and electronic effects.
The scope and relevance of gas-phase glycosyl cation structures in
relation to their corresponding condensed-phase structures are also
discussed. We expect that the workflow reviewed here to study glycosyl
cation structure and reactivity can be extended to many other reaction
types involving difficult-to-characterize ionic intermediates.
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Affiliation(s)
- Floor ter Braak
- Radboud University, Institute for Molecules and Materials, Synthetic Organic Chemistry, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Hidde Elferink
- Radboud University, Institute for Molecules and Materials, Synthetic Organic Chemistry, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
| | - Kas J. Houthuijs
- Radboud University, FELIX Laboratory, Institute of Molecules and Materials, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Jos Oomens
- Radboud University, FELIX Laboratory, Institute of Molecules and Materials, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Jonathan Martens
- Radboud University, FELIX Laboratory, Institute of Molecules and Materials, Toernooiveld 7, 6525 ED Nijmegen, The Netherlands
| | - Thomas J. Boltje
- Radboud University, Institute for Molecules and Materials, Synthetic Organic Chemistry, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands
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6
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Elferink H, Titulaer WHC, Derks MGN, Veeneman GH, Rutjes FPJT, Boltje TJ. Chloromethyl Glycosides as Versatile Synthons to Prepare Glycosyloxymethyl‐Prodrugs. Chemistry 2022; 28:e202103910. [PMID: 35045197 PMCID: PMC9304170 DOI: 10.1002/chem.202103910] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Indexed: 11/21/2022]
Abstract
This work investigates the addition of monosaccharides to marketed drugs to improve their pharmacokinetic properties for oral absorption. To this end, a set of chloromethyl glycoside synthons were developed to prepare a variety of glycosyloxymethyl‐prodrugs derived from 5‐fluorouracil, thioguanine, propofol and losartan. Drug release was studied in vitro using β‐glucosidase confirming rapid conversion of the monosaccharide prodrugs to release the parent drug, formaldehyde and the monosaccharide. To showcase this prodrug approach, a glucosyloxymethyl conjugate of the tetrazole‐containing drug losartan was used for in vivo experiments and showed complete release of the drug in a dog‐model.
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Affiliation(s)
- Hidde Elferink
- Synthetic Organic Chemistry Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Willem H. C. Titulaer
- Synthetic Organic Chemistry Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Maik G. N. Derks
- Synthetic Organic Chemistry Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Gerrit H. Veeneman
- PharmaCytics B.V., Pivot Park Kloosterstraat 9 5349 AB Oss The Netherlands
| | - Floris P. J. T. Rutjes
- Synthetic Organic Chemistry Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Thomas J. Boltje
- Synthetic Organic Chemistry Institute for Molecules and Materials Radboud University Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
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7
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Kleijne FFJ, Elferink H, Moons SJ, White PB, Boltje TJ. Characterization of Mannosyl Dioxanium Ions in Solution Using Chemical Exchange Saturation Transfer NMR Spectroscopy. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202109874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Frank F. J. Kleijne
- Synthetic organic chemistry Institute for molecules and materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Hidde Elferink
- Synthetic organic chemistry Institute for molecules and materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Sam J. Moons
- Synthetic organic chemistry Institute for molecules and materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Paul B. White
- Synthetic organic chemistry Institute for molecules and materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Thomas J. Boltje
- Synthetic organic chemistry Institute for molecules and materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
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8
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Merx J, Houthuijs KJ, Elferink H, Witlox E, Mecinović J, Oomens J, Martens J, Boltje TJ, Rutjes FPJT. Characterization of Cyclic N-Acyliminium Ions by Infrared Ion Spectroscopy. Chemistry 2021; 28:e202104078. [PMID: 34911145 PMCID: PMC9302692 DOI: 10.1002/chem.202104078] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Indexed: 11/10/2022]
Abstract
N‐Acyliminium ions are highly reactive intermediates that are important for creating CC‐bonds adjacent to nitrogen atoms. Here we report the characterization of cyclic N‐acyliminium ions in the gas phase, generated by collision induced dissociation tandem mass spectrometry followed by infrared ion spectroscopy using the FELIX infrared free electron laser. Comparison of DFT calculated spectra with the experimentally observed IR spectra provided valuable insights in the conformations of the N‐acyliminium ions.
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Affiliation(s)
- Jona Merx
- Institute for Molecules and Materials, Synthetic Organic Chemistry, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Kas J Houthuijs
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Hidde Elferink
- Institute for Molecules and Materials, Synthetic Organic Chemistry, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Eva Witlox
- Institute for Molecules and Materials, Synthetic Organic Chemistry, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Jasmin Mecinović
- Department of Physics, Chemistry and Pharmacy, University of Southern Denmark, Campusvej 55, 5230, Odense, Denmark
| | - Jos Oomens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Jonathan Martens
- Institute for Molecules and Materials, FELIX Laboratory, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Thomas J Boltje
- Institute for Molecules and Materials, Synthetic Organic Chemistry, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Floris P J T Rutjes
- Institute for Molecules and Materials, Synthetic Organic Chemistry, Radboud University, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
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9
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de Kleijne F, Elferink H, Moons S, White P, Boltje TJ. Characterization of Mannosyl Dioxanium Ions in Solution Using Chemical Exchange Saturation Transfer NMR. Angew Chem Int Ed Engl 2021; 61:e202109874. [PMID: 34519403 PMCID: PMC9305821 DOI: 10.1002/anie.202109874] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Indexed: 11/12/2022]
Abstract
The stereoselective introduction of the glycosidic bond remains one of the main challenges in carbohydrate synthesis. Characterizing the reactive intermediates of this reaction is key to develop stereoselective glycosylation reactions. Herein we report the characterization of low-populated, rapidly equilibrating, mannosyl dioxanium ions that arise from participation of a C-3 acyl group using chemical exchange saturation transfer (CEST) NMR spectroscopy. Dioxanium ion structure and equilibration kinetics were measured under relevant glycosylation conditions and highly α -selective couplings were observed suggesting glycosylation took place via this elusive intermediate.
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Affiliation(s)
- Frank de Kleijne
- Radboud University: Radboud Universiteit, Synthetic Organic Chemistry, NETHERLANDS
| | - Hidde Elferink
- Radboud University: Radboud Universiteit, Synthetic Organic Chemistry, NETHERLANDS
| | - Sam Moons
- Radboud University Nijmegen: Radboud Universiteit, Synthetic organic chemistry, NETHERLANDS
| | - Paul White
- Radboud University Nijmegen: Radboud Universiteit, Synthetic Organic Chemistry, NETHERLANDS
| | - Thomas Jan Boltje
- Radboud University, Molecular Chemistry, Heyendaalseweg 135, 6525AJ, Nijmegen, NETHERLANDS
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10
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Hansen T, Elferink H, van Hengst JMA, Houthuijs KJ, Remmerswaal WA, Kromm A, Berden G, van der Vorm S, Rijs AM, Overkleeft HS, Filippov DV, Rutjes FPJT, van der Marel GA, Martens J, Oomens J, Codée JDC, Boltje TJ. Characterization of glycosyl dioxolenium ions and their role in glycosylation reactions. Nat Commun 2020; 11:2664. [PMID: 32471982 PMCID: PMC7260182 DOI: 10.1038/s41467-020-16362-x] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 04/22/2020] [Indexed: 12/28/2022] Open
Abstract
Controlling the chemical glycosylation reaction remains the major challenge in the synthesis of oligosaccharides. Though 1,2-trans glycosidic linkages can be installed using neighboring group participation, the construction of 1,2-cis linkages is difficult and has no general solution. Long-range participation (LRP) by distal acyl groups may steer the stereoselectivity, but contradictory results have been reported on the role and strength of this stereoelectronic effect. It has been exceedingly difficult to study the bridging dioxolenium ion intermediates because of their high reactivity and fleeting nature. Here we report an integrated approach, using infrared ion spectroscopy, DFT computations, and a systematic series of glycosylation reactions to probe these ions in detail. Our study reveals how distal acyl groups can play a decisive role in shaping the stereochemical outcome of a glycosylation reaction, and opens new avenues to exploit these species in the assembly of oligosaccharides and glycoconjugates to fuel biological research.
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Affiliation(s)
- Thomas Hansen
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Hidde Elferink
- Radboud University Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Jacob M A van Hengst
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Kas J Houthuijs
- Radboud University Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Wouter A Remmerswaal
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Alexandra Kromm
- Radboud University Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Giel Berden
- Radboud University Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7-c, 6525 ED, Nijmegen, The Netherlands
| | - Stefan van der Vorm
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Anouk M Rijs
- Radboud University Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7-c, 6525 ED, Nijmegen, The Netherlands
| | - Hermen S Overkleeft
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Dmitri V Filippov
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Floris P J T Rutjes
- Radboud University Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Gijsbert A van der Marel
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands
| | - Jonathan Martens
- Radboud University Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7-c, 6525 ED, Nijmegen, The Netherlands
| | - Jos Oomens
- Radboud University Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld 7-c, 6525 ED, Nijmegen, The Netherlands.
| | - Jeroen D C Codée
- Leiden University, Leiden Institute of Chemistry, Einsteinweg 55, 2333 CC, Leiden, The Netherlands.
| | - Thomas J Boltje
- Radboud University Institute for Molecules and Materials, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands.
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11
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Elferink H, Rossing E, Huang CH, Lee BW, Cao L, Delsing DJ, Groeneveld A, Boltje TJ. Modular synthesis and immunological evaluation of suspected allergenic galactooligosaccharides. Org Biomol Chem 2019; 17:3108-3112. [PMID: 30843570 DOI: 10.1039/c9ob00108e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Galactooligosaccharides (GOS) are widely used in the food industry as prebiotics and in very rare cases, can lead to an allergic reaction. Due to the microheterogeneity of GOS it is very difficult to extract pure and well defined oligosaccharides to establish which component is responsible for the observed allergenicity. Herein, we report the chemical synthesis of a suspected allergen 4PX and three closely related oligosaccharides based on a modular approach. The fact that synthesized 4PX and a regioisomer did not cause basophil activation in subjects with confirmed GOS-allergy excludes both tetrasaccharides as key-epitopes in GOS-allergenicity in Singapore.
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Affiliation(s)
- Hidde Elferink
- Cluster for Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, The Netherlands.
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12
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Elferink H, Geurts K, Jue S, MacCormick S, Veeneman G, Boltje TJ. Synthesis and cellular uptake of carbamoylated mannose derivatives. Carbohydr Res 2019; 481:67-71. [DOI: 10.1016/j.carres.2019.06.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Revised: 06/14/2019] [Accepted: 06/14/2019] [Indexed: 01/01/2023]
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13
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Elferink H, Mensink RA, Castelijns WWA, Jansen O, Bruekers JPJ, Martens J, Oomens J, Rijs AM, Boltje TJ. The Glycosylation Mechanisms of 6,3‐Uronic Acid Lactones. Angew Chem Int Ed Engl 2019; 58:8746-8751. [DOI: 10.1002/anie.201902507] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Revised: 04/15/2019] [Indexed: 12/14/2022]
Affiliation(s)
- Hidde Elferink
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Rens A. Mensink
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Wilke W. A. Castelijns
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Oscar Jansen
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Jeroen P. J. Bruekers
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Jonathan Martens
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Jos Oomens
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Anouk M. Rijs
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Thomas J. Boltje
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
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14
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Elferink H, Mensink RA, Castelijns WWA, Jansen O, Bruekers JPJ, Martens J, Oomens J, Rijs AM, Boltje TJ. The Glycosylation Mechanisms of 6,3‐Uronic Acid Lactones. Angew Chem Int Ed Engl 2019. [DOI: 10.1002/ange.201902507] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Hidde Elferink
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Rens A. Mensink
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Wilke W. A. Castelijns
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Oscar Jansen
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Jeroen P. J. Bruekers
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Jonathan Martens
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Jos Oomens
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Anouk M. Rijs
- Radboud UniversityInstitute for Molecules and Materials, FELIX laboratory Toernooiveld 7c 6525 ED Nijmegen The Netherlands
| | - Thomas J. Boltje
- Radboud UniversityInstitute for Molecules and Materials Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
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15
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Bloemendal VRLJ, Sondag D, Elferink H, Boltje TJ, van Hest JCM, Rutjes FPJT. A Revised Modular Approach to (-)- trans-Δ 8-THC and Derivatives Through Late-Stage Suzuki-Miyaura Cross-Coupling Reactions. European J Org Chem 2019; 2019:2289-2296. [PMID: 31423106 PMCID: PMC6686972 DOI: 10.1002/ejoc.201900059] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Indexed: 12/21/2022]
Abstract
A revised modular approach to various synthetic (–)‐trans‐Δ8‐THC derivatives through late‐stage Suzuki–Miyaura cross‐coupling reactions is disclosed. Ten derivatives were synthesized allowing both sp2‐ and sp3‐hybridized cross‐coupling partners with minimal β‐hydride elimination. Importantly, we demonstrate that a para‐bromo‐substituted THC scaffold for Suzuki–Miyaura cross‐coupling reactions has been initially reported incorrectly in recent literature.
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Affiliation(s)
- Victor R L J Bloemendal
- Institute for Molecules and Materials Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands
| | - Daan Sondag
- Institute for Molecules and Materials Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands
| | - Hidde Elferink
- Institute for Molecules and Materials Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands
| | - Thomas J Boltje
- Institute for Molecules and Materials Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands
| | - Jan C M van Hest
- Eindhoven University of Technology P.O. Box 513 (STO 3.31) NL-5600 MB Eindhoven The Netherlands
| | - Floris P J T Rutjes
- Institute for Molecules and Materials Heyendaalseweg 135 NL-6525 AJ Nijmegen The Netherlands
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16
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Heise T, Pijnenborg JFA, Büll C, van Hilten N, Kers-Rebel ED, Balneger N, Elferink H, Adema GJ, Boltje TJ. Potent Metabolic Sialylation Inhibitors Based on C-5-Modified Fluorinated Sialic Acids. J Med Chem 2018; 62:1014-1021. [PMID: 30543426 PMCID: PMC6348442 DOI: 10.1021/acs.jmedchem.8b01757] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
![]()
Sialic
acid sugars on mammalian cells regulate numerous biological
processes, while aberrant expression of sialic acid is associated
with diseases such as cancer and pathogenic infection. Inhibition
of the sialic acid biosynthesis may therefore hold considerable therapeutic
potential. To effectively decrease the sialic acid expression, we
synthesized C-5-modified 3-fluoro sialic acid sialyltransferase inhibitors.
We found that C-5 carbamates significantly enhanced and prolonged
the inhibitory activity in multiple mouse and human cell lines. As
an underlying mechanism, we have identified that carbamate-modified
3-fluoro sialic acid inhibitors are more efficiently metabolized to
their active cytidine monophosphate analogues, reaching higher effective
inhibitor concentrations inside cells.
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Affiliation(s)
- Torben Heise
- Cluster for Molecular Chemistry, Institute for Molecules and Materials , Radboud University Nijmegen , Nijmegen 6525AJ , The Netherlands
| | - Johan F A Pijnenborg
- Cluster for Molecular Chemistry, Institute for Molecules and Materials , Radboud University Nijmegen , Nijmegen 6525AJ , The Netherlands
| | - Christian Büll
- Radiotherapy & OncoImmunology Laboratory, Department of Radiation Oncology , Radboudumc , Nijmegen 6525 GA , The Netherlands
| | - Niek van Hilten
- Supramolecular and Biomaterials Chemistry, Leiden Institute of Chemistry , Leiden University , Leiden 2333 CC , The Netherlands
| | - Esther D Kers-Rebel
- Radiotherapy & OncoImmunology Laboratory, Department of Radiation Oncology , Radboudumc , Nijmegen 6525 GA , The Netherlands
| | - Natasja Balneger
- Radiotherapy & OncoImmunology Laboratory, Department of Radiation Oncology , Radboudumc , Nijmegen 6525 GA , The Netherlands
| | - Hidde Elferink
- Cluster for Molecular Chemistry, Institute for Molecules and Materials , Radboud University Nijmegen , Nijmegen 6525AJ , The Netherlands
| | - Gosse J Adema
- Radiotherapy & OncoImmunology Laboratory, Department of Radiation Oncology , Radboudumc , Nijmegen 6525 GA , The Netherlands
| | - Thomas J Boltje
- Cluster for Molecular Chemistry, Institute for Molecules and Materials , Radboud University Nijmegen , Nijmegen 6525AJ , The Netherlands
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17
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Elferink H, Severijnen ME, Martens J, Mensink RA, Berden G, Oomens J, Rutjes FPJT, Rijs AM, Boltje TJ. Direct Experimental Characterization of Glycosyl Cations by Infrared Ion Spectroscopy. J Am Chem Soc 2018; 140:6034-6038. [PMID: 29656643 PMCID: PMC5958338 DOI: 10.1021/jacs.8b01236] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Indexed: 12/29/2022]
Abstract
Glycosyl cations are crucial intermediates formed during enzymatic and chemical glycosylation. The intrinsic high reactivity and short lifetime of these reaction intermediates make them very challenging to characterize using spectroscopic techniques. Herein, we report the use of collision induced dissociation tandem mass spectrometry to generate glycosyl cations in the gas phase followed by infrared ion spectroscopy using the FELIX infrared free electron laser. The experimentally observed IR spectra were compared to DFT calculated spectra enabling the detailed structural elucidation of elusive glycosyl oxocarbenium and dioxolenium ions.
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Affiliation(s)
- Hidde Elferink
- Radboud
University, Institute for Molecules and Materials, Synthetic Organic Chemistry, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Marion E. Severijnen
- Radboud
University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld
7c, 6525 ED, Nijmegen, The Netherlands
| | - Jonathan Martens
- Radboud
University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld
7c, 6525 ED, Nijmegen, The Netherlands
| | - Rens A. Mensink
- Radboud
University, Institute for Molecules and Materials, Synthetic Organic Chemistry, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Giel Berden
- Radboud
University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld
7c, 6525 ED, Nijmegen, The Netherlands
| | - Jos Oomens
- Radboud
University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld
7c, 6525 ED, Nijmegen, The Netherlands
| | - Floris P. J. T. Rutjes
- Radboud
University, Institute for Molecules and Materials, Synthetic Organic Chemistry, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Anouk M. Rijs
- Radboud
University, Institute for Molecules and Materials, FELIX Laboratory, Toernooiveld
7c, 6525 ED, Nijmegen, The Netherlands
| | - Thomas J. Boltje
- Radboud
University, Institute for Molecules and Materials, Synthetic Organic Chemistry, Heyendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
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18
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Mensink RA, Elferink H, White PB, Pers N, Rutjes FPJT, Boltje TJ. A Study on Stereoselective Glycosylations via Sulfonium Ion Intermediates. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600898] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Rens A. Mensink
- Synthetic organic chemistry; Institute for Molecules and Materials; Heyendaalseweg 135 Nijmegen The Netherlands
| | - Hidde Elferink
- Synthetic organic chemistry; Institute for Molecules and Materials; Heyendaalseweg 135 Nijmegen The Netherlands
| | - Paul B. White
- Synthetic organic chemistry; Institute for Molecules and Materials; Heyendaalseweg 135 Nijmegen The Netherlands
| | - Nathalie Pers
- Synthetic organic chemistry; Institute for Molecules and Materials; Heyendaalseweg 135 Nijmegen The Netherlands
| | - Floris P. J. T. Rutjes
- Synthetic organic chemistry; Institute for Molecules and Materials; Heyendaalseweg 135 Nijmegen The Netherlands
| | - Thomas J. Boltje
- Synthetic organic chemistry; Institute for Molecules and Materials; Heyendaalseweg 135 Nijmegen The Netherlands
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19
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Affiliation(s)
- Hidde Elferink
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Rens A. Mensink
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Paul B. White
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Thomas J. Boltje
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
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20
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Elferink H, Mensink RA, White PB, Boltje TJ. Stereoselective β-Mannosylation by Neighboring-Group Participation. Angew Chem Int Ed Engl 2016; 55:11217-20. [DOI: 10.1002/anie.201604358] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 06/02/2016] [Indexed: 11/12/2022]
Affiliation(s)
- Hidde Elferink
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Rens A. Mensink
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Paul B. White
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
| | - Thomas J. Boltje
- Institute for Molecules and Materials; Heyendaalseweg 135 6525 AJ Nijmegen The Netherlands
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