The near infra red (NIR) chiroptical properties of nickel dithiolene complexes

2015 ◽  
Vol 39 (1) ◽  
pp. 122-129 ◽  
Author(s):  
Yann Le Gal ◽  
Antoine Vacher ◽  
Vincent Dorcet ◽  
Marc Fourmigué ◽  
Jeanne Crassous ◽  
...  
Keyword(s):  
Circular Dichroism ◽  
Thin Layer ◽  
Chiroptical Properties ◽  
Infra Red ◽  
Redox Switching ◽  
Circular Dichroïsm

Circular dichroism (CD) thin layer spectro-electrochemical experiments reveal a redox switching of CD-active bands in the NIR region.

Electronic and Vibrational Circular Dichroism of Model β-Lactams: 3-Methyl- and 4-Methylazetidin-2-one

1996 ◽  
Vol 50 (5) ◽  
pp. 630-641 ◽  
Author(s):  
Jennifer McCann ◽  
Arvi Rauk ◽  
Gennadii V. Shustov ◽  
Hal Wieser ◽  
Danya Yang
Keyword(s):  
Circular Dichroism ◽  
Ab Initio ◽  
Electronic Transition ◽  
Vibrational Circular Dichroism ◽  
Protic Solvent ◽  
Free Energies ◽  
Chiroptical Properties ◽  
Circular Dichroïsm ◽  
Rotational Strengths ◽  
Simple Modeling

The chiroptical properties of the simplest chiral β-lactams, 3- and 4-methylazetidin-2-one, 1 and 2, respectively, were investigated. The experimental vibrational circular dichroism (VCD) and electronic circular dichroism (ECD) spectra were measured and compared with ab initio predictions. Both compounds were found to form dimers with calculated binding enthalpies and free energies of about −51 kJ/mol and −6 to −8 kJ/mol, respectively. The experimentally measured IR and VCD spectra were measured in concentrated nonpolar (CCl4) solution and are in agreement with the predicted IR and VCD spectra of the dimeric forms, 12 and 22, but not the monomers. The most intense dimer VCD bands originate from in-plane N-H wags, which perturb the H-bonded cyclic array. At the more dilute concentrations employed for the ECD spectra, the experimental ECD spectra in heptane were interpreted satisfactorily as arising from a mixture consisting predominantly of monomers. In protic solvent (H2O, MeOH), the ECD spectra are consistent with H-bonded monomers. Simple modeling suggests that the rotational strengths of the first electronic transition gain most of their intensity from the nonplanarity of the amide chromophore, the contributions of which follow a spiral rule previously enunciated.

Chiroptical properties of 12,15-dichloro[3.0]orthometacyclophane—correlations between molecular structure and circular dichroism spectra of a biphenylophane

1999 ◽  
Vol 10 (11) ◽  
pp. 2153-2164 ◽  
Author(s):  
Christoph Niederalt ◽  
Stefan Grimme ◽  
Sigrid D Peyerimhoff ◽  
Adam Sobanski ◽  
Fritz Vögtle ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Circular Dichroism ◽  
Circular Dichroism Spectra ◽  
Chiroptical Properties ◽  
Circular Dichroïsm

Spectroscopic and biophysical approaches for studying the structure and function of the P-glycoprotein multidrug transporter

1998 ◽  
Vol 76 (5) ◽  
pp. 695-708 ◽  
Author(s):  
Frances J Sharom ◽  
Ronghua Liu ◽  
Yolanda Romsicki
Keyword(s):  
Electron Microscopy ◽  
Circular Dichroism ◽  
Multidrug Resistance ◽  
Fluorescence Spectroscopy ◽  
Lipid Bilayers ◽  
Drug Transport ◽  
Circular Dichroism Spectroscopy ◽  
P Glycoprotein ◽  
Infra Red ◽  
Circular Dichroïsm

Multidrug resistance is a serious obstacle to the successful chemotherapeutic treatment of many human cancers. A major cause of multidrug resistance is the overexpression of a 170-kDa plasma membrane protein, known as P-glycoprotein, which appears to function as an ATP-driven efflux pump with a very broad specificity for hydrophobic drugs, peptides, and natural products. P-Glycoprotein is a member of the ABC superfamily and is proposed to consist of two homologous halves, each comprising six membrane-spanning segments and a cytosolic nucleotide binding domain. In recent years, P-glycoprotein has been purified and functionally reconstituted into lipid bilayers, where it retains both ATPase and drug transport activity. The availability of purified active protein has led to substantial advances in our understanding of the molecular structure and mechanism of action of this unique transporter. This review will focus on the recent application of fluorescence spectroscopy, infra-red spectroscopy, circular dichroism spectroscopy, electron microscopy, and other biophysical techniques to the study of P-glycoprotein structure and function.Key words: multidrug resistance, P-glycoprotein, fluorescence spectroscopy, infra-red spectroscopy, circular dichroism spectroscopy, differential scanning calorimetry, electron microscopy.

Circular dichroism, XCV. Chiroptical properties of stereoisomeric conjugated oximes, I

1991 ◽  
Vol 1991 (1) ◽  
pp. 89-91 ◽  
Author(s):  
Jadwiga Frelek ◽  
Liang Huang ◽  
Francis Kerek ◽  
Günther Snatzke ◽  
Wojciech J. Szczepek
Keyword(s):  
Circular Dichroism ◽  
Chiroptical Properties ◽  
Circular Dichroïsm
Sign in / Sign up

Export Citation Format

Share Document