Using NMR Spectroscopy and Chemical Synthesis to Establish Diastereoselectivity of NaBH4 and Meerwein–Ponndorf–Verley (MPV) Reduction of (±)-Benzoin Isopropyl Ether: A Collaborative Discovery-Based Laboratory Experiment

Control of pore window size is the standard approach for tuning gas selectivity in porous solids. Here, we present the first example where this is translated into a molecular porous liquid formed from organic cage molecules. Reduction of the cage window size by chemical synthesis switches the selectivity from Xe-selective to CH4-selective, which is understood using 129Xe, 1H, and pulsed-field gradient NMR spectroscopy.

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Controlling Gas Selectivity in Molecular Porous Liquids by Tuning the Cage Window Size

10.26434/chemrxiv.10247528 ◽

2019 ◽

Author(s):

Benjamin Egleston ◽

Konstantin V. Luzyanin ◽

Michael C. Brand ◽

Rob Clowes ◽

Michael E. Briggs ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Chemical Synthesis ◽

Field Gradient ◽

Window Size ◽

Standard Approach ◽

Porous Solids ◽

Pulsed Field Gradient Nmr ◽

Pulsed Field ◽

Cage Molecules ◽

Gas Selectivity

Control of pore window size is the standard approach for tuning gas selectivity in porous solids. Here, we present the first example where this is translated into a molecular porous liquid formed from organic cage molecules. Reduction of the cage window size by chemical synthesis switches the selectivity from Xe-selective to CH4-selective, which is understood using 129Xe, 1H, and pulsed-field gradient NMR spectroscopy.

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Radical Dehalogenation and Purine Nucleoside Phosphorylase E. coli: How Does an Admixture of 2′,3′-Anhydroinosine Hinder 2-fluoro-cordycepin Synthesis

Biomolecules ◽

10.3390/biom11040539 ◽

2021 ◽

Vol 11 (4) ◽

pp. 539

Author(s):

Alexey L. Kayushin ◽

Julia A. Tokunova ◽

Ilja V. Fateev ◽

Alexandra O. Arnautova ◽

Maria Ya. Berzina ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Chemical Synthesis ◽

Purine Nucleoside Phosphorylase ◽

Purine Nucleoside ◽

Preparative Synthesis ◽

Nucleoside Phosphorylase ◽

E Coli ◽

First Time

During the preparative synthesis of 2-fluorocordycepin from 2-fluoroadenosine and 3′-deoxyinosine catalyzed by E. coli purine nucleoside phosphorylase, a slowdown of the reaction and decrease of yield down to 5% were encountered. An unknown nucleoside was found in the reaction mixture and its structure was established. This nucleoside is formed from the admixture of 2′,3′-anhydroinosine, a byproduct in the preparation of 3-′deoxyinosine. Moreover, 2′,3′-anhydroinosine forms during radical dehalogenation of 9-(2′,5′-di-O-acetyl-3′-bromo- -3′-deoxyxylofuranosyl)hypoxanthine, a precursor of 3′-deoxyinosine in chemical synthesis. The products of 2′,3′-anhydroinosine hydrolysis inhibit the formation of 1-phospho-3-deoxyribose during the synthesis of 2-fluorocordycepin. The progress of 2′,3′-anhydroinosine hydrolysis was investigated. The reactions were performed in D2O instead of H2O; this allowed accumulating intermediate substances in sufficient quantities. Two intermediates were isolated and their structures were confirmed by mass and NMR spectroscopy. A mechanism of 2′,3′-anhydroinosine hydrolysis in D2O is fully determined for the first time.

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Chemical synthesis of GDP-fucose analogs and their utilization by the Lewis *A(1 → 4) fucosyltransferase

Canadian Journal of Chemistry ◽

10.1139/v90-165 ◽

1990 ◽

Vol 68 (7) ◽

pp. 1063-1071 ◽

Cited By ~ 74

Author(s):

Uday B. Gokhale ◽

Ole Hindsgaul ◽

Monica M. Palcic

Keyword(s):

Nmr Spectroscopy ◽

Chemical Synthesis ◽

Human Milk ◽

Immunosorbent Assay ◽

Spectrophotometric Assay ◽

Enzyme Linked Immunosorbent Assay ◽

Elisa Assay ◽

Oligosaccharide Synthesis ◽

H Nmr ◽

Nucleotide Analog

Chemical syntheses are reported for GDP-fucose (5), GDP-3-deoxy-fucose (6), and GDP-arabinose (7), the demethyl analog of 5. All three sugar nucleotides were found to act as donor substrates for an α(1 → 4) fucosyltransferase isolated from human milk when *BDGal(1 → 3)*BDGlcNAc-O(CH2)8COOMe (1) was used as the acceptor. The rate of transfer of sugar residues to 1 was measured using a coupled spectrophotometric assay and was found to be 100% (5), 2.3% (6), and 5.9% (7). The product Lea-active oligosaccharide analogs were identified by both an enzyme-linked immunosorbent assay (ELISA) and by 1H NMR spectroscopy. Keywords: glycosyltransferase, oligosaccharide synthesis, sugar-nucleotide analog, ELISA assay, fucosyltransferase.

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Detailed Investigation of the Immunodominant Role of O-Antigen Stoichiometric O-Acetylation as Revealed by Chemical Synthesis, Immunochemistry, Solution Conformation and STD-NMR Spectroscopy forShigella flexneri 3a

Chemistry - A European Journal ◽

10.1002/chem.201600567 ◽

2016 ◽

Vol 22 (31) ◽

pp. 10892-10911 ◽

Cited By ~ 12

Author(s):

Julien Boutet ◽

Pilar Blasco ◽

Catherine Guerreiro ◽

Françoise Thouron ◽

Sylvie Dartevelle ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Chemical Synthesis ◽

Solution Conformation ◽

O Antigen ◽

Std Nmr

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What Is the True Color of Fresh Meat? A Biophysical Undergraduate Laboratory Experiment Investigating the Effects of Ligand Binding on Myoglobin Using Optical, EPR, and NMR Spectroscopy

Journal of Chemical Education ◽

10.1021/ed100585t ◽

2011 ◽

Vol 88 (2) ◽

pp. 223-225 ◽

Cited By ~ 7

Author(s):

Kimberly Linenberger ◽

Stacey Lowery Bretz ◽

Michael W. Crowder ◽

Robert McCarrick ◽

Gary A. Lorigan ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Ligand Binding ◽

Laboratory Experiment ◽

Fresh Meat ◽

Undergraduate Laboratory ◽

True Color

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Chemical synthesis and NMR spectroscopy of long stable isotope labelled RNA

Chemical Communications ◽

10.1039/c7cc06747j ◽

2017 ◽

Vol 53 (96) ◽

pp. 12938-12941 ◽

Cited By ~ 9

Author(s):

J. Kremser ◽

E. Strebitzer ◽

R. Plangger ◽

M. A. Juen ◽

F. Nußbaumer ◽

...

Keyword(s):

Nmr Spectroscopy ◽

Stable Isotope ◽

Chemical Synthesis ◽

Structural Biology

A synthetic access to stable isotope modified large RNAs for structural biology is introduced.

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Structure determination, correction, and disproof of marine macrolide natural products by chemical synthesis

Organic Chemistry Frontiers ◽

10.1039/d1qo00481f ◽

2021 ◽

Author(s):

Haruhiko Fuwa

Keyword(s):

Natural Products ◽

Nmr Spectroscopy ◽

Chemical Synthesis ◽

Structure Determination ◽

Structure Elucidation ◽

Limited Availability

Despite significant advances in NMR spectroscopy, structure elucidation of natural products, especially stereochemically complex polyketides with limited availability, is still a challenging task for chemists. Recent examples of structure determination,...

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