Dataset Information

Conformational Differentiation of ?-Cyanohydroxycinnamic Acid Isomers: A Raman Spectroscopic Study.

ABSTRACT: Two ?-cyanohydroxycinnamic acid positional isomers, ?-cyano-4-hydroxycinnamic acid (CHCA4) and ?-cyano-3-hydroxycinnamic acid (CHCA3), were characterized using Raman spectroscopy. We analyzed the implications of the collected Raman spectral shifts, and verified them through other spectroscopic techniques, to arrive at plausible three dimensional structures of CHCA3 and CHCA4. The positions of these groups were mapped by systematically analyzing the orientation and type of interactions functional groups make in each CHCA isomer. We determined whether or not the carboxylic moieties are forming dimeric links and ascertained the existence of ring-ring ?-stacking interactions. We also assessed the nature of the hydrogen bonding between -CN and -OH groups. The results were then taken together to model plausible three dimensional structures for each compound. The data revealed a structure for CHCA4 that matches the published x-ray crystallographic structure. We then applied the same spectral analysis to CHCA3 to reveal its plausible three dimensional structure. The structural details revealed may account for the functional properties of the two ?-cyanohydroxycinnamic acid positional isomers.

SUBMITTER: Vedad J

PROVIDER: S-EPMC5720387 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Conformational Differentiation of α-Cyanohydroxycinnamic Acid Isomers: A Raman Spectroscopic Study.

Vedad Jayson J Domaradzki Maciej E ME Mojica Elmer-Rico E EE Chang Emmanuel J EJ Profit Adam A AA Desamero Ruel Z B RZB

Journal of Raman spectroscopy : JRS 20170727 10

Two α-cyanohydroxycinnamic acid positional isomers, α-cyano-4-hydroxycinnamic acid (CHCA4) and α-cyano-3-hydroxycinnamic acid (CHCA3), were characterized using Raman spectroscopy. We analyzed the implications of the collected Raman spectral shifts, and verified them through other spectroscopic techniques, to arrive at plausible three dimensional structures of CHCA3 and CHCA4. The positions of these groups were mapped by systematically analyzing the orientation and type of interactions functional ...[more]

PMID: 29225410

Similar Datasets

Project description:Highlights • 10 different astaxanthin (AST) geometrical isomers were analyzed by Raman spectroscopy.• Raman spectroscopy can distinguish all the geometrical isomers of AST molecules.• Structures and vibrational modes of all the AST isomers are obtained due to DFT calculations. Astaxanthin is a carotenoid widely used in food additives, nutritional product and medicines, which shows many physiological functions such as antioxidant, anti-inflammatory, anti-hypertensive and anti-diabetic activities. It has been recognized that astaxanthin has all-trans and nine cis isomers, and these geometrical isomers have very different biological activities. The process of selective enrichment, metabolism and isomerization of astaxanthin in animals remains to be studied. Therefore, identifying isomers and obtaining their structural parameters are important for understanding the active mechanism of different molecular isomers. Although the traditional methods such as high-performance liquid chromatography (HPLC) and nuclear magnetic resonance (NMR) spectroscopy can be used to distinguish these isomers, these methods generally require considerable testing time, cost, sample volume, and hardly be applied in vivo. In this work, Raman spectroscopy combined with density functional theory (DFT) calculation was introduced to study different geometrical isomers of astaxanthin. The theoretical and experimental Raman spectra are in agreement, and we have demonstrated that all the known ten geometrical isomers of astaxanthin can be readily distinguished using this spectroscopic approach. The astaxanthin molecular vibrational modes, geometric structures, energies of ten geometric isomers are systematically scrutinized. Moreover, a lot of structural and Raman problems unsolved previously have been solved by the DFT-based spectral analysis. Therefore, this work provides an effective way for identification of different astaxanthin geometrical isomers, and may have important significance for promoting the research of astaxanthin isomers on biological property mechanisms and related applications in food molecular science.

Dataset Information

Conformational Differentiation of ?-Cyanohydroxycinnamic Acid Isomers: A Raman Spectroscopic Study.

Publications

Conformational Differentiation of α-Cyanohydroxycinnamic Acid Isomers: A Raman Spectroscopic Study.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets