Structural studies on aryl-substituted enaminoketones and their thio analogues. Part I. Analysis of high-resolution 1 H, 13 C NMR and 13 C CP MAS spectra combined with GIAO-DFT calculations

2009 ◽  
Vol 47 (10) ◽  
pp. 830-842 ◽  
Author(s):  
Marta Bugaj ◽  
Piotr A. Baran ◽  
Piotr Bernatowicz ◽  
Patrycja Brożek ◽  
Krystyna Kamieńska-Trela ◽  
...  
Keyword(s):  
High Resolution ◽  
Dft Calculations ◽  
Structural Studies ◽  
C Nmr

scholarly journals A New Cucurbitane Glycoside from Siraitia grosvenorii

2015 ◽  
Vol 10 (9) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Venkata Sai Prakash Chaturvedula ◽  
Srinivasa Rao Meneni
Keyword(s):  
High Resolution ◽  
Phytochemical Study ◽  
Mass Spectral ◽  
High Resolution Mass ◽  
Siraitia Grosvenorii ◽  
Commercial Extract ◽  
Resolution Mass ◽  
C Nmr

A systematic phytochemical study of the commercial extract of Luo Han Guo ( Siraitia grosvenorii) resulted in the isolation of an additional minor new cucurbitane glycoside, mogroside V A1 (1). The structure of the new compound was characterized on the basis of 1D (1H and 13C NMR) and 2D (COSY, HMQC, HMBC and NOESY) NMR and high resolution mass spectral (HRMS) data, as well as hydrolysis studies.

Evaluation of Antinociceptive and Anti-Inflammatory Activities of a New Triterpene Saponin from Bauhinia variegata Leaves

2009 ◽  
Vol 64 (11-12) ◽  
pp. 798-808 ◽  
Author(s):  
Mona A. Mohamed ◽  
Madeha R. Mammoud ◽  
Heiko Hayen
Keyword(s):  
High Resolution ◽  
Spectral Data ◽  
Cinnamic Acid ◽  
Cinnamic Acid Derivatives ◽  
Triterpene Saponin ◽  
H Nmr ◽  
Antischistosomal Activity ◽  
Bauhinia Variegata ◽  
Anti Inflammatory ◽  
C Nmr

A new triterpene saponin, named as 23-hydroxy-3α-[O-α-L-1C4-rhamnopyranosyl-(1´´4´)- O-α-L-4C1-arabinopyranosyl-oxy]olean-12-en-28-oic acid O-α-L-1C4-rhamnopyranosyl- (1´´´´´→4´´´´)-O-β-D-4C1-glucopyranosyl-(1´´´´→6´´´)-O-β-D-4C1-glucopyranosyl ester (9), was isolated from the leaves of Bauhinia variegata Linn. In addition, six flavonoid compounds along with two cinnamic acid derivatives were isolated and identified based on their chromatographic properties, and chemical and spectral data (ESI-high resolution-MSn, 1H NMR, 13C NMR, 1H-1H COSY, HSQC, and HMBC). Compound 9 was found to be nontoxic (LD50) and to have significant anti-inflammatory and antinociceptive activities. It also showed a slight antischistosomal activity.

A Novel Method for 13C-NMR Spectroscopy of Polymer in Emulsion: Quantitative Analysis of Microstructure of Crosslinked Polybutadiene in Latex

1999 ◽  
Vol 72 (5) ◽  
pp. 844-853 ◽  
Author(s):  
Seiichi Kawahara ◽  
Saori Bushimata ◽  
Takashi Sugiyama ◽  
Chihiro Hashimoto ◽  
Yasuyuki Tanaka
Keyword(s):  
Nmr Spectroscopy ◽  
High Resolution ◽  
13C Nmr ◽  
Lattice Relaxation ◽  
13C Nmr Spectroscopy ◽  
Lattice Relaxation Time ◽  
Solid Sample ◽  
Spin Lattice Relaxation ◽  
High Resolution Spectrum ◽  
C Nmr

Abstract A novel analytical method using high resolution 13C-NMR spectroscopy to study polymer latex, which is a heterogeneous system comprising polymer dispersoid and water, is described. The appropriate concentrations of surfactant and dried rubber content of a polybutadiene latex, which give the best spectrum, were found to be 1 w/v % and 10%, respectively. The half-widths of resonance peaks for the latex sample were almost identical to the half-widths obtained in solution, which were about one-third the width of those obtained using a solid sample of either a crosslinked or soluble polybutadiene. Nevertheless, the signal to noise ratio for the latex sample was slightly smaller than that for the solution sample. The values of spin-lattice relaxation time, T1, for the latex sample were similar to those for the solid sample. These demonstrate that the latex state C-NMR spectroscopy will be a powerful technique for structural characterization of crosslinked gels in the dispersoid because it gives a high resolution spectrum comparable to solution state spectroscopy, showing short T1 values corresponding to those for solid state C-NMR spectroscopy. High resolution latex state 13C-NMR spectroscopy was used to determine the concentrations of the various isomers of the polybutadiene in the dispersoid.

Structural studies of digitoxin and related cardenolides by two-dimensional NMR

1990 ◽  
Vol 68 (2) ◽  
pp. 272-277 ◽  
Author(s):  
Torbjörn Drakenberg ◽  
Peter Brodelius ◽  
Deane D. McIntyre ◽  
Hans J Vogel
Keyword(s):  
Nmr Spectroscopy ◽  
Nmr Spectra ◽  
Chair Conformation ◽  
Coupling Constants ◽  
Two Dimensional ◽  
Structural Studies ◽  
Solution Conformation ◽  
Phase Sensitive ◽  
Multiple Relay ◽  
C Nmr

The 1H and 13C NMR spectra of the cardenolides digitoxigenin, digoxigenin, digitoxin, and mono- and bis-digitoxigenin digitoxosides have been completely assigned by two-dimensional NMR spectroscopy. The techniques used include phase-sensitive COSY, multiple relay COSY, and carbon–proton correlation (HETCOR and HMQC) spectra. Various aspects of the solution conformation of the steroid moiety of digitoxin and digoxigenin could be determined from coupling constants and NOE difference experiments and they are indicative of an all-chair conformation. The carbohydrate rings in digitoxin and the mono- and bis-digitoxigenin digitoxosides are also in the chair conformation. Keywords: cardenolides, digitoxigenin, digitoxin, 2-dimensional NMR, conformational analysis.

scholarly journals Синтез, структура и магнитные свойства многослойных наногетероструктур Fe|MgO|Cr|MgO|Fe

2021 ◽  
Vol 63 (9) ◽  
pp. 1306
Author(s):  
Е.М. Якунина ◽  
Е.А. Кравцов ◽  
Yu.N. Khaydukov ◽  
Н.О. Антропов ◽  
В.В. Проглядо
Keyword(s):  
Magnetic Properties ◽  
High Resolution ◽  
Exchange Interaction ◽  
Magnetic Moments ◽  
Ferromagnetic Material ◽  
Structural Studies ◽  
X Ray ◽  
Structural And Magnetic Properties ◽  
Metal Layers

Layered nanoheterostructures Fe | MgO | Cr | MgO | Fe is an artificial ferromagnetic material in which the exchange interaction of the magnetic moments of Fe layers through intermediate dielectric and metal layers can lead to magnetic configurations that are not realized in the well-studied Fe | MgO | Fe and Fe | Cr | Fe. In this work, we investigated the correlations of the structural and magnetic properties of layered nanoheterostructures Fe (10 nm) | MgO (1.5 nm) | Cr (t nm) | MgO (1.5 nm) | Fe (7 nm) (thickness t = 0.9 and 1.8 nm). Structural studies performed using X-ray diffractometry and high-resolution reflectometry confirmed the formation of a textured structure and revealed its well-defined layered character with sharp interlayer boundaries.

High-resolution solid-state C NMR study of per(3,6-anhydro)-α-cyclodextrin based polymers and of their chromium complexes

2005 ◽  
Vol 61 (1) ◽  
pp. 88-94 ◽  
Author(s):  
S CADARS ◽  
M FORAY ◽  
A GADELLE ◽  
G GERBAUD ◽  
M BARDET
Keyword(s):  
Solid State ◽  
High Resolution ◽  
Chromium Complexes ◽  
Nmr Study ◽  
C Nmr

scholarly journals Hydroquinone–pyrrole dyads with varied linkers

2016 ◽  
Vol 12 ◽  
pp. 89-96 ◽  
Author(s):  
Hao Huang ◽  
Christoffer Karlsson ◽  
Maria Strømme ◽  
Martin Sjödin ◽  
Adolf Gogoll
Keyword(s):  
Dft Calculations ◽  
Electrical Energy ◽  
Energy Storage Devices ◽  
Active Materials ◽  
Electrical Energy Storage ◽  
Storage Devices ◽  
H Nmr ◽  
Redox Active ◽  
Homo Lumo ◽  
C Nmr

A series of pyrroles functionalized in the 3-position with p-dimethoxybenzene via various linkers (CH2, CH2CH2, CH=CH, C≡C) has been synthesized. Their electronic properties have been deduced from 1H NMR, 13C NMR, and UV–vis spectra to detect possible interactions between the two aromatic subunits. The extent of conjugation between the subunits is largely controlled by the nature of the linker, with the largest conjugation found with the trans-ethene linker and the weakest with the aliphatic linkers. DFT calculations revealed substantial changes in the HOMO–LUMO gap that correlated with the extent of conjugation found experimentally. The results of this work are expected to open up for use of the investigated compounds as components of redox-active materials in sustainable, organic electrical energy storage devices.

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