Results 31 to 40 of about 2,440 (209)

A confidence level algorithm for the determination of absolute configuration using vibrational circular dichroism or raman optical activity [PDF]

, 2011
Spectral comparison is an important part of the assignment of the absolute configuration (AC) by vibrational circular dichroism (VCD), or equally by Raman optical activity (ROA). In order to avoid bias caused by personal interpretation, numerical methods
Alecu, Becke, Buffeteau, Cappelli, De Gelder, Debie, Debie, Devlin, Devlin, Devlin, Gal, Guo, Hehre, Kuppens, Kuppens, Kuppens, Kuppens, Lee, Nafie, Nafie, Pulay, Rouhi, Shen, Stephens, Stephens   +24 more
core   +1 more source

Conformations of Steroid Hormones: Infrared and Vibrational Circular Dichroism Spectroscopy

Molecules, 2023
Steroid hormone molecules may exhibit very different functionalities based on the associated functional groups and their 3D arrangements in space, i.e., absolute configurations and conformations.
Yanqing Yang, Anna Krin, Xiaoli Cai, Mohammad Reza Poopari, Yuefei Zhang, James R. Cheeseman, Yunjie Xu   +6 more
doaj   +1 more source

Reaction Monitoring Using Mid-Infrared Laser-Based Vibrational Circular Dichroism [PDF]

, 2014
Changes in vibrational circular dichroism (VCD) were recorded on-line during a chemical reaction. The chiral complex nickel-(–)-sparteine chloride was hydrolyzed to free (–)-sparteine base in a biphasic system of sodium hydroxide solution and ...
Bonmarin, Bourˇ, Chen, Freedman, Freedman, Guo, Guo, Hache, He, Hendler, Hendler, Hsu, Izumi, Keiderling, Lewis, Lórenz-Fonfría, Lüdeke, Mason, Mattigod, Mendonça, Müller, Nafie, Nafie, Press, Rhee, Zewail   +25 more
core   +1 more source

Assignment Through Chiroptical Methods of The Absolute Configuration of Fungal Dihydropyranpyran-4-5-Diones Phytotoxins, Potential Herbicides for Buffelgrass (Cenchrus ciliaris) Biocontrol

Molecules, 2019
Radicinin and cochliotoxin (1 and 2) two phytotoxic pyranpyran-4,5-diones were isolated together with their close metabolites 3-epi-radicinin, radicinol, and its 3-epimer (3−5), from the culture filtrates of Cochliobolus australiensis, a fungus ...
Ernesto Santoro, Giuseppe Mazzeo, Giulia Marsico, Marco Masi, Giovanna Longhi, Stefano Superchi, Antonio Evidente, Sergio Abbate   +7 more
doaj   +1 more source

Chiral Phase Transfer Catalysis in the Asymmetric Synthesis of a 3,3-Disubstituted Isoindolinone and Determination of Its Absolute Configuration by VCD Spectroscopy

Molecules, 2020
In this work we report our endeavors toward the development of an asymmetric synthesis of a 3,3-disubstituted isoindolinone, dimethyl 2-(1-methyl-3-oxoisoindolin-1-yl)malonate, via asymmetric cascade reaction of 2-acetylbenzonitrile with dimethylmalonate
Guglielmo Monaco, Maximilian Tiffner, Antonia Di Mola, Wouter Herrebout, Mario Waser, Antonio Massa   +5 more
doaj   +1 more source

Solid Phase Nitrosylation of Enantiomeric Cobalt(II) Complexes

Chemistry, 2021
Accompanied by a change in color from red to black, the enantiomorphic phases of the cobalt complexes of a chiral salen ligand (L2−, Co(L)·CS2, and Co(L) (L = LS,S or LR,R)) chemisorb NO (g) at atmospheric pressure and rt over hours for the CS2 solvated ...
Mads Sondrup Møller, Morten Czochara Liljedahl, Vickie McKee, Christine J. McKenzie   +3 more
doaj   +1 more source

Vibrational Excitons in CH-Stretching Fundamental and Overtone Vibrational Circular Dichroism Spectra [PDF]

, 2005
A set of vibrational circular dichroism (VCD) spectra in the CH-stretching fundamental region for about twenty compounds belonging to the class of essential oils was empirically analyzed by the use of a sort of vibrational exciton mechanism, involving ...
ABBATE S, GANGEMI R, LAUX L, LEBON F, LONGHI G   +4 more
core   +1 more source

Insights into the Structures of Bilirubin and Biliverdin from Vibrational and Electronic Circular Dichroism: History and Perspectives

Molecules, 2023
In this work we review research activities on a few of the most relevant structural aspects of bilirubin (BR) and biliverdin (BV). Special attention is paid to the exocyclic C=C bonds being in mostly Z rather than E configurations, and to the overall ...
Giovanna Longhi, Simone Ghidinelli, Sergio Abbate, Giuseppe Mazzeo, Marco Fusè, Stefan E. Boiadjiev, David A. Lightner   +6 more
doaj   +1 more source

Raman Optical Activity: A Reliable Chiroptical Technique

CHIMIA, 2008
Vibrational optical activity (VOA) is a research field in full expansion. The two main areas where VOA is used are the determination of absolute configurations and the investigation of the secondary and tertiary solution structures of ...
Jacques Haesler, Werner Hug
doaj   +1 more source

Conformational Analysis of Diterpene Lactone Andrographolide towards Reestablishment of Its Absolute Configuration via Theoretical and Experimental ECD and VCD Methods

Indonesian Journal of Chemistry, 2020
Andrographolide, the major constituent from the terrestrial plant Andrographis paniculata is a much-studied bioactive ent-labdane diterpene lactone and has become an important medicinal intermediate.
Muhamad Faid A Kadir, Agustono Wibowo, Fatimah Salim, El Hassane Anouar, Khalijah Awang, Moses Kiprotich Langat, Rohaya Ahmad   +6 more
doaj   +1 more source