Results 101 to 110 of about 1,362,496 (337)

Research on 1H NMR spectrum optimization of 2,3-benzodiazepines based on conformational isomerism

Results in Chemistry
To address the issue of multiple sets of signal peaks and irregular peak shapes in the 1H NMR spectra of some 2,3-benzodiazepines due to conformational isomerism, 1H NMR experiments were conducted using 2,3-benzodiazepines 1 as examples, with variations ...
Fei Zhang, Ya-Li Ding
doaj   +1 more source

5-Dimethylamino-1-phenylchromeno[2,3-c]pyrazol-4(1H)-one

Molbank, 2010
The title compound was prepared by treatment of 5-fluoro-1-phenylchromeno [2,3-c]pyrazol-4(1H)-one with aqueous dimethylamine. Detailed spectroscopic data (1H NMR, 13C NMR, 15N NMR, IR, MS) are presented.
Wolfgang Holzer, Angelika Ebner
doaj   +1 more source

A 1H NMR relaxometry investigation of gel-pore drying shrinkage in cement pastes

, 2016
The first systematic study of the temporal evolution of the pore-size-distribution (PSD) in mature cement pastes following one and two cycles of drying and rewetting is presented. The PSD is measured using 1H nuclear magnetic resonance (NMR) relaxometry.
A. Gajewicz, E. Gartner, K. Kang, P. McDonald, V. Yermakou   +4 more
semanticscholar   +1 more source

Switching the stereochemical outcome of 6-endo-trig cyclizations; Synthesis of 2,6-Cis-6-substituted 4-oxopipecolic acids [PDF]

, 2012
A base-mediated 6-endo-trig cyclization of readily accessible enone-derived α-amino acids has been developed for the direct synthesis of novel 2,6-cis-6- substituted-4-oxo-L-pipecolic acids. A range of aliphatic and aryl side chains were tolerated by
Agami C., Alastair A. Cant, Andrew Sutherland, Bernasconi R., Boger D. L., Cant A. A., Carbonnel S., Fowler L. S., Fowler L. S., Golubev A., Graham L. Simpson, Gutiérrez M. C., Hans Martin Senn, He M., Ireland R. E., Jatoi W. B., Johnson F., Jung J.-C., Kadouri-Puchot C., Lamarre D., Lindsay S. Fowler, Marin J., Mark Daly, Merino P., Occhiato E. G., Occhiato E. G., Purkayastha N., Purkayastha N., Romeo J. T., Romo D., Rudisill D. E., Schenk V. W., Smith A. B., Smith A. B., Smith A. B., Swindells D. C., Tanaka H., Vanderhaeghe H., Weigend F., Zacharius R. M., Zhao Y., Zhao Y.   +41 more
core   +1 more source

Unusual Swelling Behavior of Hydrogels Modified with Spiropyran as Appendage or Crosslinker

Advanced Functional Materials, EarlyView.
Not so innocent after all—spiropyran crosslinkers in methylenebisacrylamide‐crosslinked poly(acrylamide‐co‐acrylic acid) hydrogels increase crosslinking density, but also, counterintuitively, increase swelling. Charge complexation, cooperative chemo‐mechanical effects, and aggregation may explain these observations.
Michael M. Lerch, Ankita Shastri, Thomas B. H. Schroeder, Amos Meeks, Shucong Li, Anna V. Shneidman, Michael Aizenberg, Joanna Aizenberg   +7 more
wiley   +1 more source

Complete Assignments of NMR Spectral Data of Three C19-Diterpenoid Alkaloids

Chinese Journal of Magnetic Resonance, 2019
C19-diterpenoid alkaloids have complex and diverse structures, posing great challenges for nuclear magnetic resonance (NMR)-based structural elucidation. Three C19-diterpenoid alkaloids, including taronenine E (1), chasmaconitine (2) and vilmorisine (3),
YIN Tian-peng, WANG Ya-rong, WANG Min, SHI Wen-zhi, ZHANG Zheng-qian, HE Sha-sha   +5 more
doaj   +1 more source

1H-NMR as a Structural and Analytical Tool of Intra- and Intermolecular Hydrogen Bonds of Phenol-Containing Natural Products and Model Compounds

Molecules, 2014
Experimental parameters that influence the resolution of 1H-NMR phenol OH signals are critically evaluated with emphasis on the effects of pH, temperature and nature of the solvents.
P. Charisiadis, V. Kontogianni, C. Tsiafoulis, A. Tzakos, Michael G Siskos, I. Gerothanassis   +5 more
semanticscholar   +1 more source

O,N,N-Pincer ligand effects on oxidatively induced carbon–chlorine coupling reactions at palladium [PDF]

, 2015
The syntheses of two families of sterically tuneable O,N,N pro-ligands are reported, namely the 2-(phenyl-2′-ol)-6-imine-pyridines, 2-(C6H4-2′-OH),6-(CMe[double bond, length as m-dash]NAr)C5H3N [Ar = 4-i-PrC6H4 (HL1a), 2,6-i-Pr2C6H3 (HL1b)] and the 2 ...
Cross, WB, Hope, EG, Singh, K, Solan, GA, Wright, LA   +4 more
core   +1 more source

Three‐dimensional Antimony Sulfide Based Flat Optics

Advanced Functional Materials, EarlyView.
This work presents the development of a grayscale electron beam lithography (g‐EBL) method for fabricating antimony trisulfide (Sb2S3) nanostructures with customizable 3D profiles. The refractive index of g‐EBL patterned Sb2S3 is determined based on the synergy of genetic algorithm and transfer matrix method.
Wei Wang, Uwe Hübner, Anne Gärtner, Tao Chen, Joseph Köbel, Franka Jahn, Daniel Repp, Abhrodeep Dey, Henrik Schneidwind, Andrea Dellith, Jan Dellith, Torsten Wieduwilt, Matthias Zeisberger, Tanveer Ahmed Shaik, Astrid Bingel, Markus A. Schmidt, Jer‐Shing Huang, Ulf Peschel, Volker Deckert   +18 more
wiley   +1 more source

Boron carboxylate catalysis of homoallylboration. [PDF]

, 2014
Boron tris(trifluoroacetate) is identified as the first effective catalyst for the homoallyl- and homocrotylboration of aldehydes by cyclopropylcarbinylboronates.
Dugas, Gabrielle J, Houk, KN, Krauss, Isaac J, Lam, Yu-hong   +3 more
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