1
|
Singh Y, Geringer SA, Demchenko AV. Synthesis and Glycosidation of Anomeric Halides: Evolution from Early Studies to Modern Methods of the 21st Century. Chem Rev 2022; 122:11701-11758. [PMID: 35675037 DOI: 10.1021/acs.chemrev.2c00029] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Advances in synthetic carbohydrate chemistry have dramatically improved access to common glycans. However, many novel methods still fail to adequately address challenges associated with chemical glycosylation and glycan synthesis. Since a challenge of glycosylation has remained, scientists have been frequently returning to the traditional glycosyl donors. This review is dedicated to glycosyl halides that have played crucial roles in shaping the field of glycosciences and continue to pave the way toward our understanding of chemical glycosylation.
Collapse
Affiliation(s)
- Yashapal Singh
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Scott A Geringer
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States
| | - Alexei V Demchenko
- Department of Chemistry and Biochemistry, University of Missouri-St. Louis, One University Boulevard, St. Louis, Missouri 63121, United States.,Department of Chemistry, Saint Louis University, 3501 Laclede Avenue, St. Louis, Missouri 63103, United States
| |
Collapse
|
2
|
Kolahdouzan K, Ogba OM, O'Leary DJ. 1H NMR Studies of Intramolecular OH/OH Hydrogen Bonds via Titratable Isotope Shifts. J Org Chem 2021; 87:1732-1744. [PMID: 34783564 DOI: 10.1021/acs.joc.1c01910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Methanol titrations of partially deuterated 1,4- and 1,3-diols dissolved in nonpolar solvents such as CD2Cl2 and benzene-d6 have provided 1H NMR measurements of OH/OD isotope shifts, diagnostic for intact intramolecular hydrogen bonds, under conditions of increasing protic solvent concentration. 1,4- and 1,3-diols with conformationally favored intramolecular OH/OH hydrogen bonds can be titrated to constant isotope shift values, albeit with variable sign, in the presence of excess methanol equivalents, providing evidence for intact intramolecular hydrogen bonds under these conditions. Conversely, the isotope shift in a 1,3-diol with a conformationally labile intramolecular hydrogen bond titrated to zero when in the presence of excess equivalents methanol, consistent with intramolecular hydrogen bond rupture under these conditions. Additionally, the titration behavior of hydroxyl chemical shifts in diols and protected derivatives has revealed significant OH/OD isotope shifts in the absence of chemical shift differences (δOHin = δOHout) that are necessary for an equilibrium isotope effect, lending evidence for an intrinsic contribution to the isotope effect. OH/OD isotope shift titration thus provides a means for understanding the origins of these isotope effects and for probing the intact or nonintact nature of intramolecular OH/OH hydrogen bonds in response to intermolecular hydrogen bonds provided by a protic solvent.
Collapse
Affiliation(s)
- Kavoos Kolahdouzan
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, California 91711, United States
| | - O Maduka Ogba
- Chemistry and Biochemistry Program, Schmid College of Science and Technology, Chapman University, Orange, California 92886, United States
| | - Daniel J O'Leary
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, California 91711, United States
| |
Collapse
|
3
|
Brown GD, Bauer J, Osborn HMI, Kuemmerle R. A Solution NMR Approach To Determine the Chemical Structures of Carbohydrates Using the Hydroxyl Groups as Starting Points. ACS OMEGA 2018; 3:17957-17975. [PMID: 31458388 PMCID: PMC6644132 DOI: 10.1021/acsomega.8b02136] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 12/07/2018] [Indexed: 06/10/2023]
Abstract
An efficient NMR approach is described for determining the chemical structures of the monosaccharide glucose and four disaccharides, namely, nigerose, gentiobiose, leucrose and isomaltulose. This approach uses the 1H resonances of the -OH groups, which are observable in the NMR spectrum of a supercooled aqueous solution, as the starting point for further analysis. The 2D-NMR technique, HSQC-TOCSY, is then applied to fully define the covalent structure (i.e., the topological relationship between C-C, C-H, and O-H bonds) that must be established for a novel carbohydrate before proceeding to further conformational studies. This process also leads to complete assignment of all 1H and 13C resonances. The approach is exemplified by analyzing the monosaccharide glucose, which is treated as if it were an "unknown", and also by fully assigning all the NMR resonances for the four disaccharides that contain glucose. It is proposed that this technique should be equally applicable to the determination of chemical structures for larger carbohydrates of unknown composition, including those that are only available in limited quantities from biological studies. The advantages of commencing the structure elucidation of a carbohydrate at the -OH groups are discussed with reference to the now well-established 2D-/3D-NMR strategy for investigation of peptides/proteins, which employs the -NH resonances as the starting point.
Collapse
Affiliation(s)
- Geoffrey D. Brown
- Department of Chemistry and Reading School of Pharmacy, The University of Reading, Whiteknights, Reading RG6 6AP, United Kingdom
| | - Julia Bauer
- Department of Chemistry and Reading School of Pharmacy, The University of Reading, Whiteknights, Reading RG6 6AP, United Kingdom
| | - Helen M. I. Osborn
- Department of Chemistry and Reading School of Pharmacy, The University of Reading, Whiteknights, Reading RG6 6AP, United Kingdom
| | - Rainer Kuemmerle
- Bruker
Biospin AG, NMR Division, Industriestrasse 26, CH-8117 Fallanden, Switzerland
| |
Collapse
|
4
|
Okauchi T, Nakamura S, Tsubaki K, Asakawa M, Kitamura M. Synthesis of (±)-myo-inositol 4-methylenephosphonate via Rh-Catalyzed hydrogenation of vinylphosphonate. Carbohydr Res 2017; 448:24-27. [DOI: 10.1016/j.carres.2017.05.018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 05/25/2017] [Accepted: 05/25/2017] [Indexed: 11/15/2022]
|
5
|
Battistel MD, Azurmendi HF, Freedberg DI. Glycan OH Exchange Rate Determination in Aqueous Solution: Seeking Evidence for Transient Hydrogen Bonds. J Phys Chem B 2017; 121:683-695. [PMID: 27995788 DOI: 10.1021/acs.jpcb.6b10594] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Hydrogen bonds (Hbonds) are important stabilizing forces in biomolecules. However, for glycans in aqueous solution, direct NMR detection of Hbonds is elusive because of their transient nature. Here, we present Isotope-based Natural-abundance TOtal correlation eXchange SpectroscopY (INTOXSY), a new 1H-13C heteronuclear single quantum coherence-total correlation spectroscopy based method, to extract OH groups' exchange rate constants (kex) for molecules in natural 13C abundance and show that OH Hbonds can be inferred from "slower" H/D kex. We evaluate kex measured with INTOXSY in light of those extracted with line-shape analysis. Subsequently, we use a set of common glycans to establish a kex reference basis set and to infer the existence of transient Hbonds involving OH donor groups. Then, we report kex values for a series of mono- and disaccharides, as well as for oligosaccharides sialyl Lewis X and β-cyclodextrin, and compare the results with those from the reference set to extract Hbond information. Finally, we utilize NMR experimental data in conjunction with molecular dynamics simulations to establish donor and acceptor Hbond pairs. Our exchange rate measurements indicate that OH/OD exchange rates, kHD, values <10 s-1 are consistent with transient Hbond OH groups and potential acceptor groups can be uncovered through MD simulations.
Collapse
Affiliation(s)
- Marcos D Battistel
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration , 10903 New Hampshire Avenue, Silver Spring, Maryland 20903, United States
| | - Hugo F Azurmendi
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration , 10903 New Hampshire Avenue, Silver Spring, Maryland 20903, United States
| | - Darón I Freedberg
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration , 10903 New Hampshire Avenue, Silver Spring, Maryland 20903, United States
| |
Collapse
|
6
|
Pelletier G, Zwicker A, Allen CL, Schepartz A, Miller SJ. Aqueous Glycosylation of Unprotected Sucrose Employing Glycosyl Fluorides in the Presence of Calcium Ion and Trimethylamine. J Am Chem Soc 2016; 138:3175-82. [PMID: 26859619 PMCID: PMC4817112 DOI: 10.1021/jacs.5b13384] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
We report a synthetic glycosylation reaction between sucrosyl acceptors and glycosyl fluoride donors to yield the derived trisaccharides. This reaction proceeds at room temperature in an aqueous solvent mixture. Calcium salts and a tertiary amine base promote the reaction with high site-selectivity for either the 3'-position or 1'-position of the fructofuranoside unit. Because nonenzymatic aqueous oligosaccharide syntheses are underdeveloped, mechanistic studies were carried out in order to identify the origin of the selectivity, which we hypothesized was related to the structure of the hydroxyl group array in sucrose. The solution conformation of various monodeoxysucrose analogs revealed the co-operative nature of the hydroxyl groups in mediating both this aqueous glycosyl bond-forming reaction and the site-selectivity at the same time.
Collapse
Affiliation(s)
- Guillaume Pelletier
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520-8107
| | - Aaron Zwicker
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520-8107
| | - C. Liana Allen
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520-8107
| | - Alanna Schepartz
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520-8107
| | - Scott J. Miller
- Department of Chemistry, Yale University, 225 Prospect Street, New Haven, CT 06520-8107
| |
Collapse
|
7
|
Battistel MD, Azurmendi HF, Yu B, Freedberg DI. NMR of glycans: shedding new light on old problems. PROGRESS IN NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY 2014; 79:48-68. [PMID: 24815364 DOI: 10.1016/j.pnmrs.2014.01.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Accepted: 01/10/2014] [Indexed: 06/03/2023]
Abstract
The diversity in molecular arrangements and dynamics displayed by glycans renders traditional NMR strategies, employed for proteins and nucleic acids, insufficient. Because of the unique properties of glycans, structural studies often require the adoption of a different repertoire of tailor-made experiments and protocols. We present an account of recent developments in NMR techniques that will deepen our understanding of structure-function relations in glycans. We open with a survey and comparison of methods utilized to determine the structure of proteins, nucleic acids and carbohydrates. Next, we discuss the structural information obtained from traditional NMR techniques like chemical shifts, NOEs/ROEs, and coupling-constants, along with the limitations imposed by the unique intrinsic characteristics of glycan structure on these approaches: flexibility, range of conformers, signal overlap, and non-first-order scalar (strong) coupling. Novel experiments taking advantage of isotopic labeling are presented as an option for overcoming spectral overlap and raising sensitivity. Computational tools used to explore conformational averaging in conjunction with NMR parameters are described. In addition, recent developments in hydroxyl detection and hydrogen bond detection in protonated solvents, in contrast to traditional sample preparations in D2O for carbohydrates, further increase the tools available for both structure information and chemical shift assignments. We also include previously unpublished data in this context. Accurate determination of couplings in carbohydrates has been historically challenging due to the common presence of strong-couplings. We present new strategies proposed for dealing with their influence on NMR signals. We close with a discussion of residual dipolar couplings (RDCs) and the advantages of using (13)C isotope labeling that allows gathering one-bond (13)C-(13)C couplings with a recently improved constant-time COSY technique, in addition to the commonly measured (1)H-(13)C RDCs.
Collapse
Affiliation(s)
- Marcos D Battistel
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448, United States
| | - Hugo F Azurmendi
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448, United States
| | - Bingwu Yu
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448, United States
| | - Darón I Freedberg
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, MD 20852-1448, United States.
| |
Collapse
|
8
|
Lomas JS. 1H NMR spectra of alkane-1,3-diols in benzene: GIAO/DFT shift calculations. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2013; 51:469-481. [PMID: 23784999 DOI: 10.1002/mrc.3973] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 05/07/2013] [Accepted: 05/07/2013] [Indexed: 06/02/2023]
Abstract
The proton nuclear magnetic resonance (NMR) spectra of propane-1,3-diol, 2-methylpropane-1,3-diol, 2,2-dimethylpropane-1,3-diol, butane-1,3-diol, 3-methylbutane-1,3-diol, pentane-2,4-diols (dl and meso), 2-methylpentane-2,4-diol and cyclohexane-1,3-diols (cis and trans) in benzene have been analysed. The conformer distribution and the NMR shifts of these diols have been computed on the basis of density functional theory, the solvent being included by means of the integral equation formalism phase continuum model (IEFPCM) implemented in Gaussian 09. Relative Gibbs energies of all conformers are calculated at the Perdew, Burke and Ernzerhof (PBE)0/6-311 + G(d,p) level, and NMR shifts by the gauge-including atomic orbital method with the PBE0/6-311 + G(d,p) geometry and the cc-pVTZ basis set. Vicinal coupling constants for 1,2- and 1,3-diols are rationalised in terms of relative conformer populations and geometries. The NMR shifts of hydrogen-bonded protons in individual conformers of alkane-1,n-diols show a very rough correlation with the OH⋯OH distances. The computed overall NMR shifts for CH protons in 1,2- and 1,3-diols are systematically high but correlate very well with the experimental values, with a gradient of 1.07 ± 0.01. Some values for nonequivalent methylene protons in 1,3-diols are reversed, calculation giving enhanced values for the proton anti to the COH bonds. Errors in the NMR shifts computed for the OH protons of nonsymmetrical diols appear to be related to relative populations of conformers where one or other of the OH groups is the donor. Some results based on the second-order Møller-Plesset approach, the Becke three-parameter Lee-Yang-Parr method and on the IEFPCM solvation model implemented in Gaussian 03 are included.
Collapse
Affiliation(s)
- John S Lomas
- Univ Paris Diderot, Sorbonne Paris Cité, ITODYS, UMR 7086, F-75205, Paris, France
| |
Collapse
|
9
|
Battistel MD, Pendrill R, Widmalm G, Freedberg DI. Direct Evidence for Hydrogen Bonding in Glycans: A Combined NMR and Molecular Dynamics Study. J Phys Chem B 2013; 117:4860-9. [DOI: 10.1021/jp400402b] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Marcos D. Battistel
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, Maryland 20852-1448, United States
| | - Robert Pendrill
- Department of Organic Chemistry,
Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Göran Widmalm
- Department of Organic Chemistry,
Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Darón I. Freedberg
- Laboratory of Bacterial Polysaccharides, Center for Biologics Evaluation and Research, Food and Drug Administration, 1401 Rockville Pike, Rockville, Maryland 20852-1448, United States
| |
Collapse
|
10
|
Perrin CL. Secondary equilibrium isotope effects on acidity. ADVANCES IN PHYSICAL ORGANIC CHEMISTRY 2010. [DOI: 10.1016/s0065-3160(08)44003-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
11
|
O'Leary DJ, Hickstein DD, Hansen BKV, Hansen PE. Theoretical and NMR Studies of Deuterium Isotopic Perturbation of Hydrogen Bonding in Symmetrical Dihydroxy Compounds. J Org Chem 2009; 75:1331-42. [DOI: 10.1021/jo902075z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Daniel J. O'Leary
- Department of Chemistry, Bowdoin College, 6600 College Station, Brunswick, Maine 04011
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, California 91711
| | - Daniel D. Hickstein
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, California 91711
| | - Bjarke K. V. Hansen
- Department of Science, Systems and Models, Roskilde University, P.O. Box 260, DK-4000 Roskilde, Denmark
| | - Poul Erik Hansen
- Department of Science, Systems and Models, Roskilde University, P.O. Box 260, DK-4000 Roskilde, Denmark
| |
Collapse
|
12
|
Chen CS, Yu YP, Lin BC, Gervay-Hague J, Fang JM, Hsu CP, Wu SH. The Observation of the C-H···Osp3Hydrogen Bond in Trisialic Acid Lactone and Its Implications for Cooperative Lactonization. European J Org Chem 2009. [DOI: 10.1002/ejoc.200900148] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
13
|
Kuno L, Biali SE. Isotopic perturbation of the conformational equilibrium in methylene-functionalized calixarenes. J Org Chem 2009; 74:48-57. [PMID: 19007131 DOI: 10.1021/jo8020538] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The 400 MHz 1H NMR spectrum of the tetramethoxycalixarene 2 (possessing hydroxyl groups at the bridges) in commercial acetone-d6 displays five signals (an isotopic multiplet) for a pair of methoxy groups. Inspection of the X-ray structures of 2 and its isomer 3 indicates that in the adopted 1,3-alternate conformation, the methoxy groups intramolecularly hydrogen bonded to neighboring OH groups are oriented "in" (pointing toward the cavity). Upon dissolution of 2 in acetone-d6, none, some, or all of the OH protons exchange with the deuterium atoms present in the residual water of the solvent. Several species (mutually relating as isotopomers and isotopologues) differing in the number and positions of the deuterated hydroxyl groups are possible for 2. In three of these species, the "in"-"out"/"out"-"in" conformational equilibrium of a pair of methoxy groups is nondegenerate. The four external lines of the apparent multiplet are ascribed to a single- and double-isotopic perturbation of the "in"-"out" conformational equilibrium of a pair of methoxy groups. On the basis of the assignment of the signals to the individual species and their statistical distribution, the intensities of the components of the isotopic multiplet obtained at different isotopic enrichments of the hydroxyl groups could be simulated. A sample of 2 55% deuterated at the hydroxyl groups in CDCl3 displayed an isotopic multiplet consisting of nine signals. The isotopic multiplet observed for the OH groups of 2 in acetone-d6 was simulated at different deuteration enrichments.
Collapse
Affiliation(s)
- Lev Kuno
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel
| | | |
Collapse
|
14
|
Singh V, Schramm VL. Transition-state analysis of S. pneumoniae 5'-methylthioadenosine nucleosidase. J Am Chem Soc 2007; 129:2783-95. [PMID: 17298059 PMCID: PMC2522316 DOI: 10.1021/ja065082r] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Kinetic isotope effects (KIEs) and computer modeling are used to approximate the transition state of S. pneumoniae 5'-methylthioadenosine/S-adenosylhomocysteine nucleosidase (MTAN). Experimental KIEs were measured and corrected for a small forward commitment factor. Intrinsic KIEs were obtained for [1'-3H], [1'-14C], [2'-3H], [4'-3H], [5'-3H(2)], [9-15N] and [Me-3H(3)] MTAs. The intrinsic KIEs suggest an SN1 transition state with no covalent participation of the adenine or the water nucleophile. The transition state was modeled as a stable ribooxacarbenium ion intermediate and was constrained to fit the intrinsic KIEs. The isotope effects predicted a 3-endo conformation for the ribosyl oxacarbenium-ion corresponding to H1'-C1'-C2'-H2' dihedral angle of 70 degrees. Ab initio Hartree-Fock and DFT calculations were performed to study the effect of polarization of ribosyl hydroxyls, torsional angles, and the effect of base orientation on isotope effects. Calculations suggest that the 4'-3H KIE arises from hyperconjugation between the lonepair (n(p)) of O4' and the sigma* (C4'-H4') antibonding orbital owing to polarization of the 3'-hydroxyl by Glu174. A [methyl-3H(3)] KIE is due to hyperconjugation between np of sulfur and sigma* of methyl C-H bonds. The van der Waal contacts increase the 1'-3H KIE because of induced dipole-dipole interactions. The 1'-3H KIE is also influenced by the torsion angles of adjacent atoms and by polarization of the 2'-hydroxyl. Changing the virtual solvent (dielectric constant) does not influence the isotope effects. Unlike most N-ribosyltransferases, N7 of the leaving group adenine is not protonated at the transition state of S. pneumoniae MTAN. This feature differentiates the S. pneumoniae and E. coli transition states and explains the 10(3)-fold decrease in the catalytic efficiency of S. pneumoniae MTAN relative to that from E. coli.
Collapse
Affiliation(s)
- Vipender Singh
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, 1300 Morris Park Avenue, Bronx, New York-10461
| | - Vern L. Schramm
- Department of Biochemistry, Albert Einstein College of Medicine, Bronx, 1300 Morris Park Avenue, Bronx, New York-10461
| |
Collapse
|
15
|
J. O’Leary D, E. Anderson C, J. Pickrell A, L. Sperry S, E. Vasquez T, G. Custer T, B. Fierman M, C. Lazar D, W. Brown Z, S. Iskenderian W, D. Hickstein D. NMR Detection of Intramolecular OH/OH Hydrogen Bond Networks: An Approach Using Isotopic Perturbation and Hydrogen Bond Mediated OH···OH J-Coupling. HETEROCYCLES 2007. [DOI: 10.3987/com-06-s(k)40] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
16
|
Hansen PE. Isotope effect on chemical shifts in hydrogen-bonded systems. J Labelled Comp Radiopharm 2007. [DOI: 10.1002/jlcr.1440] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
17
|
Abstract
This review describes recent developments from our laboratory involving the synthesis of the structurally complex, pyrazinone-containing dragmacidin alkaloids.
Collapse
Affiliation(s)
- Neil K Garg
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | | |
Collapse
|
18
|
Anderson CE, Britt DK, Sangji S, O'Leary DJ, Anderson CD, Rychnovsky SD. Direct Assignment of the Relative Configuration in Acyclic 1,3-Diols by 1H NMR Spectroscopy. Org Lett 2005; 7:5721-3. [PMID: 16321031 DOI: 10.1021/ol052539d] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[chemical reaction: see text]. Using an operationally simple deuterium isotopic perturbation method, the relative configuration of 1,3-diols can be determined directly using 1H NMR spectroscopy. A comparison of the OH chemical shifts for OH/OH and OH/OD isotopomers provides a reliable assessment of the relative configuration of the diol; anti-1,3-diols within polyacetate and polypropionate frameworks have upfield isotope shifts of 2-16 ppb, whereas syn-1,3-diols show upfield isotope shifts of 20-33 ppb.
Collapse
Affiliation(s)
- Carolyn E Anderson
- Department of Chemistry, Pomona College, Claremont, California 91711, USA
| | | | | | | | | | | |
Collapse
|
19
|
Sulfonate protecting groups. Synthesis of O- and C-methylated inositols: d- and l-ononitol, d- and l-laminitol, mytilitol and scyllo-inositol methyl ether. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.02.073] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
20
|
Chelation controlled regiospecific O-substitution of myo-inositol orthoesters: convenient access to orthogonally protected myo-inositol derivatives. Tetrahedron 2005. [DOI: 10.1016/j.tet.2004.11.025] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
21
|
Allen BD, Cintrat JC, Faucher N, Berthault P, Rousseau B, O'Leary DJ. An Isosparteine Derivative for Stereochemical Assignment of Stereogenic (Chiral) Methyl Groups Using Tritium NMR: Theory and Experiment. J Am Chem Soc 2004; 127:412-20. [PMID: 15631492 DOI: 10.1021/ja045265i] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
(N-CHDT)-(alpha)-isosparteinium ditosylamide can be used in conjunction with tritium NMR spectroscopy to assign the configuration of an intact stereogenic (chiral) methyl group. The S-CHDT group has a (3)H chemical shift that is 49 ppb downfield of the R-CHDT resonance. The sign and magnitude of this chemical shift difference of these diastereotopic tritium nuclei are found to be in agreement with predictions made via a purely ab initio computational approach. The chemical shift difference is due to an equilibrium isotope effect originating from a novel CH(3)(...)N hydrogen bond. Despite the improved tritium chemical shift dispersion, this method is not useful for determining the enantiopurity of CHDTN(Tos)(2) due to partial racemization that occurs during the derivatization step. Milder methylation conditions are described for reactions using methyl p-toluenesulfonate or methyl-d(3) triflate. These studies suggest that (-)-(alpha)-isosparteine is a potential new reagent for chirality analysis of methyl groups originating from suitably reactive electrophiles.
Collapse
Affiliation(s)
- Benjamin D Allen
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, California 91711, USA
| | | | | | | | | | | |
Collapse
|
22
|
Sureshan KM, Shashidhar MS, Praveen T, Das T. Regioselective Protection and Deprotection of Inositol Hydroxyl Groups. Chem Rev 2003; 103:4477-503. [PMID: 14611268 DOI: 10.1021/cr0200724] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Kana M Sureshan
- Division of Organic Synthesis, National Chemical Laboratory, Pune 411 008, India
| | | | | | | |
Collapse
|
23
|
Lewis BE, Schramm VL. Binding equilibrium isotope effects for glucose at the catalytic domain of human brain hexokinase. J Am Chem Soc 2003; 125:4785-98. [PMID: 12696897 DOI: 10.1021/ja0298242] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have utilized tritium isotope effects to probe the in vitro binding equilibrium between glucose and human brain hexokinase (E.C.2.7.1.1). Replacing a backbone hydrogen atom in glucose with tritium can significantly increase or decrease the equilibrium association constant. Specifically, the equilibrium tritium isotope effects are 1.027 +/- 0.002, 0.927 +/- 0.0003, 1.027 +/- 0.004, 1.051 +/- 0.001, 0.988 +/- 0.001, and 1.065 +/- 0.003 for [1-t]-, [2-t]-, [3-t]-, [4-t]-, [5-t]-, and [6,6-t(2)]glucose, respectively. We have shown that the existence of prebinding equilibrium isotope effects can contribute to binding isotope effect studies but that this effect is insignificant for glucose binding to hexokinase. The binding isotope effects are interpreted in the context of structural studies of hexokinase-glucose complexes. Ab initio calculations on 2-propanol with or without a hydrogen bonding partner, in steric collision with formaldehyde or methane, and on ethanol, cyclohexanol and 1-hydroxymethyl-tetrahydropyran are presented to clarify the magnitude of isotope effects possible in such interactions and the accompanying changes in free energy. Position-specific binding isotope effects provide direct evidence of the partial deprotonation and activation of O6 by Asp657, of other hydrogen bonding interactions with ionic residues, and of the steric compression of CH2 by the backbone carbonyl of Ser603.
Collapse
Affiliation(s)
- Brett E Lewis
- The Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, New York 10461, USA
| | | |
Collapse
|
24
|
Vasquez TE, Bergset JM, Fierman MB, Nelson A, Roth J, Khan SI, O'Leary DJ. Using equilibrium isotope effects to detect intramolecular OH/OH hydrogen bonds: structural and solvent effects. J Am Chem Soc 2002; 124:2931-8. [PMID: 11902884 DOI: 10.1021/ja016879f] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A comparative (1)H NMR study of partially deuterated 1,3- and 1,4-diols has demonstrated that intramolecular hydrogen bonds of different geometry can give rise to equilibrium isotope shifts of opposite sign in hydrogen-bond-accepting solvents such as DMSO-d(6), acetone-d(6), and THF-d(8). The sign inversion is interpreted in terms of the ability of solvent molecules to form competitive intermolecular hydrogen bonds with the diol and in terms of the limiting chemical shifts for the interior and exterior hydroxyl groups. Deuterium is shown to prefer the intermolecular solvent hydrogen bond by 10.9 +/- 0.5 cal/mol for 1,4-diol 3 dissolved in DMSO-d(6) at room temperature. Pyridine-d(5) is shown to be capable of amplifying positive (downfield) isotope shifts measured in DMSO-d(6), in some cases by as much as a factor of 3. Its use is demonstrated for the assignment of the syn or anti relative configuration of 2,4-pentanediol and for the amplification of isotope shifts used to detect intramolecular hydrogen bonds in alpha- and beta-cyclodextrin. Studies in apolar solvents such as CD(2)Cl(2) and benzene-d(6) reveal that the isotope shift is negative (upfield) for all hydrogen bond geometries studied. Larger isotope shifts are measured in benzene-d(6), and a rationale for this amplification is presented. The use of apolar solvents is particularly useful for assigning the syn or anti configuration of 2,4-pentanediol.
Collapse
Affiliation(s)
- Thomas E Vasquez
- Department of Chemistry, Pomona College, 645 North College Avenue, Claremont, CA 91711, USA
| | | | | | | | | | | | | |
Collapse
|
25
|
López de la Paz M, Ellis G, Pérez M, Perkins J, Jiménez-Barbero J, Vicent C. Carbohydrate Hydrogen-Bonding Cooperativity − Intramolecular Hydrogen Bonds and Their Cooperative Effect on Intermolecular Processes − Binding to a Hydrogen-Bond Acceptor Molecule. European J Org Chem 2002. [DOI: 10.1002/1099-0690(200203)2002:5<840::aid-ejoc840>3.0.co;2-i] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
26
|
Perrin CL, Kim YJ. Isotopic perturbation of resonance in a homologous series of metal complexes with allylic cation character. J PHYS ORG CHEM 2000. [DOI: 10.1002/1099-1395(200011)13:11<752::aid-poc320>3.0.co;2-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
27
|
Sureshan K, Shashidhar M. Regioselective O-acylation of myo-inositol 1,3,5-orthoesters: the role of acyl migration. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)00561-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
|
28
|
A head-to-head comparison of α- and β-alkoxy effects on stereoselectivity. Nucleophilic additions to a cyclohexanone substituted with five axial CO bonds. Tetrahedron Lett 1999. [DOI: 10.1016/s0040-4039(99)01167-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
29
|
Kozár T, Nifant'ev NE, Grosskurth H, Dabrowski U, Dabrowski J. Conformational changes due to vicinal glycosylation: the branched alpha-L-Rhap(1-2)[beta-D-Galp(1-3)]-beta-D-Glc1-OMe trisaccharide compared with its parent disaccharides. Biopolymers 1998; 46:417-32. [PMID: 9798429 DOI: 10.1002/(sici)1097-0282(199811)46:6<417::aid-bip6>3.0.co;2-v] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Conformations of the alpha-L-Rhap(1-2)-beta-D-Glc1-OMe and beta-D-Galp(1-3)-beta-D-Glc1-OMe disaccharides and the branched title trisaccharide were examined in DMSO-d6 solution by 1H-nmr. The distance mapping procedure was based on rotating frame nuclear Overhauser effect (NOE) constraints involving C- and O-linked protons, and hydrogen-bond constraints manifested by the splitting of the OH nmr signals for partially deuteriated samples. An "isotopomer-selected NOE" method for the unequivocal identification of mutually hydrogen-bonded hydroxyl groups was suggested. The length of hydrogen bonds thus detected is considered the only one motionally nonaveraged nmr-derived constraint. Molecular mechanics and molecular dynamics methods were used to model the conformational properties of the studied oligosaccharides. Complex conformational search, relying on a regular phi, psi-grid based scanning of the conformational space of the selected glycosidic linkage, combined with simultaneous modeling of different allowed orientations of the pendant groups and the third, neighboring sugar residue, has been carried out. Energy minimizations were performed for each member of the phi, psi grid generated set of conformations. Conformational clustering has been done to group the minimized conformations into families with similar values of glycosidic torsion angles. Several stable syn and anti conformations were found for the 1-->2 and 1-->3 bonds in the studied disaccharides. Vicinal glycosylation affected strongly the occupancy of conformational states in both branches of the title trisaccharide. The preferred conformational family of the trisaccharide (with average phi, psi values of 38 degrees, 17 degrees for the 1-->2 and 48 degrees, 1 degree for the 1-->3 bond, respectively) was shown by nmr to be stabilized by intramolecular hydrogen bonding between the nonbonded Rha and Gal residues.
Collapse
Affiliation(s)
- T Kozár
- Institute of Experimental Physics, Slovak Academy of Sciences, Kosice, Slovak Republic
| | | | | | | | | |
Collapse
|
30
|
Luque FJ, López JM, López de la Paz M, Vicent C, Orozco M. Role of Intramolecular Hydrogen Bonds in the Intermolecular Hydrogen Bonding of Carbohydrates. J Phys Chem A 1998. [DOI: 10.1021/jp981690k] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | | | | | - Modesto Orozco
- Departament de Bioquímica i Biologia Molecular, Facultat de Química, Universitat de Barcelona, Martí i Franquès 1, Barcelona 08028, Spain
| |
Collapse
|
31
|
|
32
|
Landersjö C, Stenutz R, Widmalm G. Conformational Flexibility of Carbohydrates: A Folded Conformer at the φ Dihedral Angle of a Glycosidic Linkage. J Am Chem Soc 1997. [DOI: 10.1021/ja970473e] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Clas Landersjö
- Contribution from the Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Roland Stenutz
- Contribution from the Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Göran Widmalm
- Contribution from the Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| |
Collapse
|