Structural studies of 2-(3′,4′-dihydroxyphenyl)-7-β-D-glucopyranos-1-O-yl-8-hydroxychroman-4-one in the liquid and solid states by means of 2D NMR spectroscopy and DFT calculations

2002 ◽  
pp. 1059-1065 ◽  
Author(s):  
S. Olejniczak ◽  
K. Ganicz ◽  
M. Tomczykowa ◽  
J. Gudej ◽  
M. J. Potrzebowski
Keyword(s):  
Nmr Spectroscopy ◽  
Dft Calculations ◽  
2D Nmr ◽  
Structural Studies ◽  
2D Nmr Spectroscopy ◽  
Solid States

Structural studies of an arabinan from the stems of Ephedra sinica by methylation analysis and 1D and 2D NMR spectroscopy

2015 ◽  
Vol 121 ◽  
pp. 449-456 ◽  
Author(s):  
Yong-Gang Xia ◽  
Jun Liang ◽  
Bing-You Yang ◽  
Qiu-Hong Wang ◽  
Hai-Xue Kuang
Keyword(s):  
Nmr Spectroscopy ◽  
2D Nmr ◽  
Structural Studies ◽  
Methylation Analysis ◽  
2D Nmr Spectroscopy ◽  
Ephedra Sinica

Structural Studies of Chelirubine and Chelilutine Free Bases

1998 ◽  
Vol 63 (7) ◽  
pp. 1045-1055 ◽  
Author(s):  
Jiří Dostál ◽  
Jiří Slavík ◽  
Milan Potáček ◽  
Radek Marek ◽  
Otakar Humpa ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Quantum Chemical ◽  
2D Nmr ◽  
Molecular Symmetry ◽  
Structural Studies ◽  
Free Base ◽  
2D Nmr Spectroscopy ◽  
Sanguinaria Canadensis ◽  
First Time

The structures of chelirubine and chelilutine free bases have been examined by 2D NMR spectroscopy and mass spectrometry. Chelirubine chloride (1a) upon treatment with Na2CO3 yielded free base which possessed the constitution of bis(5,6-dihydrochelirubin-6-yl) ether (2a). The free base of chelilutine (1b) was determined to be bis(5,6-dihydrochelilutin-6-yl) ether (2b). The aqueous NH3 treatment of chelilutine (1b) produced bis(5,6-dihydrochelilutin-6-yl)amine (3b). 6-Hydroxy-5,6-dihydrochelirubine (4a) and 6-hydroxy-5,6-dihydrochelilutine (4b) were detected only in CDCl3 solution by NMR spectroscopy. In CDCl3, the compound 2b underwent hydrolysis to 4b that was immediately followed by the reverse condensation to a diastereomer of 2b. Pseudokinetics of this reaction was followed by NMR spectroscopy and quantum chemical calculations were carried out to support the suggested type of molecular symmetry alteration. The known alkaloid dihydrochelirubine (5) was isolated for the first time from Sanguinaria canadensis.

Studies on the reactions between the DNA bases and a model α,β-unsaturated oxoaldehyde

2015 ◽  
Vol 39 (12) ◽  
pp. 9171-9180 ◽  
Author(s):  
Donata Pluskota-Karwatka ◽  
Malwina Muńko ◽  
Marcin Hoffmann ◽  
Martyna Kuta ◽  
Leif Kronberg
Keyword(s):  
Nmr Spectroscopy ◽  
Dft Calculations ◽  
2D Nmr ◽  
Dna Bases ◽  
2D Nmr Spectroscopy

Two sets of adducts of 2′-dC with a model oxoenal were characterised based on 2D NMR spectroscopy. DFT calculations indicated that two mechanisms can be involved in these compounds formation. The instability of one of these products leads to deamination of 2′-dC.

scholarly journals Thiazol-4-one derivatives from the reaction of monosubstituted thioureas with maleimides: structures and factors determining the selectivity and tautomeric equilibrium in solution

2016 ◽  
Vol 12 ◽  
pp. 2563-2569 ◽  
Author(s):  
Alena S Pankova ◽  
Pavel R Golubev ◽  
Alexander F Khlebnikov ◽  
Alexander Yu Ivanov ◽  
Mikhail A Kuznetsov
Keyword(s):  
Nmr Spectroscopy ◽  
Nitrogen Atom ◽  
Dft Calculations ◽  
Alkyl Group ◽  
2D Nmr ◽  
Tautomeric Equilibrium ◽  
Methyl Ethyl ◽  
2D Nmr Spectroscopy ◽  
Alkyl Aryl ◽  
Exocyclic Nitrogen Atom

2-(Alkyl(aryl)amino)thiazol-4(5H)-ones can regioselectively be prepared from monoalkyl(aryl)thioureas and maleimides. In solution, the former heterocycles exist in a tautomeric equilibrium with 2-(alkyl(aryl)imino)thiazolidin-4-ones and the substituent on the exocyclic nitrogen atom governs the ratio of these tautomers. Isomers with the alkyl group in the endocyclic position can be obtained from N-methyl(ethyl)thioureas. 2D NMR spectroscopy and DFT calculations rationalize experimental results.

Demonstration of 2D NMR Spectroscopy in a Powered Magnet at 25 T Using Cascade Field Regulation

2019 ◽  
Author(s):  
Benjamin D. McPheron ◽  
Jeffrey L. Schiano ◽  
Brian F. Thomson ◽  
Kiran K. Shetty ◽  
William W. Brey
Keyword(s):  
Nmr Spectroscopy ◽  
2D Nmr ◽  
2D Nmr Spectroscopy

scholarly journals Ambient-Temperature Synthesis of (E)-N-(3-(tert-Butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanimine

Molbank ◽  
10.3390/m1250 ◽  
2021 ◽  
Vol 2021 (3) ◽  
pp. M1250
Author(s):  
Diana Becerra ◽  
Justo Cobo ◽  
Juan-Carlos Castillo
Keyword(s):  
Mass Spectrometry ◽  
Nmr Spectroscopy ◽  
Ambient Temperature ◽  
Magnesium Sulfate ◽  
Elemental Analysis ◽  
Condensation Reaction ◽  
2D Nmr ◽  
2D Nmr Spectroscopy ◽  
Temperature Synthesis ◽  
Tert Butyl

We report the ambient-temperature synthesis of novel (E)-N-(3-(tert-butyl)-1-methyl-1H-pyrazol-5-yl)-1-(pyridin-2-yl)methanamine 3 in 81% yield by a condensation reaction between 3-(tert-butyl)-1-methyl-1H-pyrazol-5-amine 1 and 2-pyridinecarboxaldehyde 2 in methanol using magnesium sulfate as a drying agent. The N-pyrazolyl imine 3 was full characterized by IR, 1D, and 2D NMR spectroscopy, mass spectrometry, and elemental analysis.

Highly NIR-emitting ytterbium complexes containing 2-(tosylaminobenzylidene)-N-benzoylhydrazone anions: structure in solution and use for bioimaging

2021 ◽  
Author(s):  
Anton D Kovalenko ◽  
Alexander A. Pavlov ◽  
Ilya D. Ustinovich ◽  
Alena S. Kalyakina ◽  
Alexander S Goloveshkin ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Lanthanide Complexes ◽  
2D Nmr ◽  
2D Nmr Spectroscopy ◽  
Ytterbium Complexes ◽  
Solution Behaviour ◽  
Structure In Solution

Abstract: Solution behaviour in DMSO using 1D and 2D NMR spectroscopy was performed for lanthanide complexes Ln(L)(HL) and Ln(HL)2Cl, containing non-macrocyclic 2-(tosylamino)-benzylidene-N-benzoylhydrazone (H2L), and the structure of [Yb(L)]+ cation in...

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