New Aspect of Chirality or Mirror Symmetry Effect in Organic Chemistry, Physics, and Two-Component Biostructures

Current Organic Chemistry ◽

10.2174/1385272825666210610142049 ◽

2021 ◽

Vol 25 ◽

Author(s):

Valerii A. Pavlov

Keyword(s):

Mirror Symmetry ◽

Mirror Neurons ◽

Racemic Mixture ◽

Two Component System ◽

Component Structure ◽

Asymmetric Catalytic ◽

Chiral Compounds ◽

Two Component ◽

The Difference ◽

Symmetry Effect

: The difference in the physical properties of a racemic mixture and enantiomers indicates that the two-component structure of a racemate can acquire new properties compared to pure enantiomers as components. The spectrum of the differences includes the melting point temperatures, density, weight, catalytic activity, and other properties. Such a two-component system of chiral compounds is analyzed in the context of chemistry, biology, and physics. The study covers asymmetric catalytic reactions, chiral macromolecular compounds structure, chiral trajectories of micro- and macro-objects, biological structures, as well as chiral objects, including mirror neurons, twins, flora-fauna biostructure, etc. The comparative analysis reveals a perfectly different time dependence of all the listed chiral processes.

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THE MOLECULAR DIAMETER OF DEUTERIUM AS DETERMINED BY VISCOSITY MEASUREMENTS

Canadian Journal of Research ◽

10.1139/cjr35-005 ◽

1935 ◽

Vol 12 (1) ◽

pp. 57-62 ◽

Cited By ~ 13

Author(s):

A. B. Van Cleave ◽

O. Maass

Keyword(s):

Liquid Water ◽

Hydrogen Molecule ◽

Deuterium Oxide ◽

Molecular Volume ◽

Two Component System ◽

Component System ◽

Viscosity Measurements ◽

Two Component ◽

The Difference ◽

Deuterium Molecule

The viscosities of deuterium over the range 23 to −183 °C. have been measured. The viscosities of the two-component system deuterium-hydrogen have been measured over the whole concentration range at 22 °C. The results show that the deuterium molecule has the same diameter as the hydrogen molecule. The interest attached to the viscosity results for the two-component system are pointed out. The difference between the molecular volume of liquid deuterium oxide and that of liquid water is attributed by the authors to a difference in equilibrium between associated and non-associated molecules in the respective systems.

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Possible Physical Basis of Mirror Symmetry Effect in Racemic Mixtures of Enantiomers: From Wallach’s Rule, Nonlinear Effects, B–Z DNA Transition, and Similar Phenomena to Mirror Symmetry Effects of Chiral Objects

Symmetry ◽

10.3390/sym12060889 ◽

2020 ◽

Vol 12 (6) ◽

pp. 889 ◽

Cited By ~ 3

Author(s):

Valerii A. Pavlov ◽

Yaroslav V. Shushenachev ◽

Sergey G. Zlotin

Keyword(s):

Mirror Symmetry ◽

Mirror Neurons ◽

Nonlinear Effects ◽

Mirror Image ◽

Similar Nature ◽

Biological Phenomena ◽

Similar Chemical ◽

Racemic Mixtures ◽

Z Dna ◽

Symmetry Effect

Effects associated with mirror symmetry may be underlying for a number of phenomena in chemistry and physics. Increase in the density and melting point of the 50%L/50%D collection of enantiomers of a different sign (Wallach’s rule) is probably based on a physical effect of the mirror image. The catalytic activity of metal complexes with racemic ligands differs from the corresponding complexes with enantiomers as well (nonlinear effect). A similar difference in the physical properties of enantiomers and racemate underlies L/D inversion points of linear helical macromolecules, helical nanocrystals of magnetite and boron nitride etc., B–Z DNA transition and phenomenon of mirror neurons may have a similar nature. Here we propose an explanation of the Wallach effect along with some similar chemical, physical, and biological phenomena related to mirror image.

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Fluorescence Spectroscopy of Enantiomeric Amide Compounds Enforced by Chiral Light

Applied Sciences ◽

10.3390/app112311375 ◽

2021 ◽

Vol 11 (23) ◽

pp. 11375

Author(s):

Alessandro Belardini ◽

Emilija Petronijevic ◽

Ramin Ghahri ◽

Daniele Rocco ◽

Fabiana Pandolfi ◽

...

Keyword(s):

Mirror Symmetry ◽

Low Cost ◽

Polarization State ◽

Polarized Light ◽

Green Emission ◽

Optical Excitation ◽

Plasmonic Nanostructures ◽

Chiral Molecules ◽

Chiral Compounds ◽

The Difference

Chirality, the absence of mirror symmetry, governs behavior in most biologically important molecules, thus making the chiral recognition of great importance in the pharmaceutical and agrochemical industries, as well as medicine. Chiral molecules can be characterized by means of optical experiments based on chiro-optical excitation of molecules. Specifically, chiral absorptive materials differently absorb left- and right-circular polarized light, i.e., they possess circular dichroism (CD). Unfortunately, the natural CD of most molecules is very low and lies in the ultraviolet range. Fluorescence-detected CD is a fast and sensitive tool for investigation of chiral molecules which emit light; ultralow CD in absorption can be detected as the difference in emission. In this work, we perform fluorescence-detected CD on novel chiral amide compounds, designed specifically for visible green emission; we synthesize two enantiomeric fluorescent compounds using low-cost starting compounds and easy purification. We investigate different solutions of the enantiomers at different concentrations, and we show that the fluorescence of the intrinsically chiral compounds depends on the polarization state of the penetrating light, which is absorbed at 400 nm and emits across the green wavelength range. We believe that these compounds can be coupled with plasmonic nanostructures, which further shows promise in applications regarding chiral sensing or chiral emission.

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