Azobenzene/Tetraethyl Ammonium Photochromic Potassium Channel Blockers: Scope and Limitations for Design of Para-Substituted Derivatives with Specific Absorption Band Maxima and Thermal Isomerization Rate

Azobenzene/tetraethyl ammonium photochromic ligands (ATPLs) are photoactive compounds with a large variety of photopharmacological applications such as nociception control or vision restoration. Absorption band maximum and lifetime of the less stable isomer are important characteristics that determine the applicability of ATPLs. Substituents allow to adjust these characteristics in a range limited by the azobenzene/tetraethyl ammonium scaffold. The aim of the current study is to find the scope and limitations for the design of ATPLs with specific spectral and kinetic properties by introducing para substituents with different electronic effects. To perform this task we synthesized ATPLs with various electron acceptor and electron donor functional groups and studied their spectral and kinetic properties using flash photolysis and conventional spectroscopy techniques as well as quantum chemical modeling. As a result, we obtained diagrams that describe correlations between spectral and kinetic properties of ATPLs (absorption maxima of E and Z isomers of ATPLs, the thermal lifetime of their Z form) and both the electronic effect of substituents described by Hammett constants and structural parameters obtained from quantum chemical calculations. The provided results can be used for the design of ATPLs with properties that are optimal for photopharmacological applications.

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Novel oxidation state — zinc(III) in chelate with 3,7,11,15-tetraazaporphine and one fluorine ligand: Quantum-chemical modeling

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424619500470 ◽

2019 ◽

Vol 23 (06) ◽

pp. 685-689 ◽

Cited By ~ 2

Author(s):

Oleg V. Mikhailov ◽

Denis V. Chachkov

Keyword(s):

Oxidation State ◽

Quantum Chemical Calculation ◽

Ground State ◽

Quantum Chemical ◽

Structural Parameters ◽

Dft Method ◽

Fluoride Ion ◽

Chemical Calculation ◽

Chemical Modeling ◽

The Given

Based on the results of a quantum chemical calculation using the DFT method, the possibility of the existence of a zinc heteroligand complex with 3,7,11,15-tetraazaporphine and fluoride ion with an oxidation state of Zn(III), unusual for the given element, is shown. Data on the structural parameters and multiplicity of the ground state of this complex are also presented.

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DFT Quantum-Chemical Modeling Molecular Structures of Cobalt Macrocyclic Complexes with Porphyrazine or Its Benzo-Derivatives and Two Oxygen Acido Ligands

International Journal of Molecular Sciences ◽

10.3390/ijms21239085 ◽

2020 ◽

Vol 21 (23) ◽

pp. 9085

Author(s):

Oleg V. Mikhailov ◽

Denis V. Chachkov

Keyword(s):

Quantum Chemical ◽

Structural Parameters ◽

Metal Chelate ◽

Calculated Data ◽

Dft Method ◽

Molecular Structures ◽

Chemical Calculation ◽

Chemical Modeling ◽

Bond Angles ◽

Donor Nitrogen

Based on the results of a quantum chemical calculation using the DFT method with the OPBE/TZVP and B3PW91/TZVP levels, the possibility of the existence of three cobalt heteroligand complexes containing in the inner coordination sphere porphyrazine, di[benzo]- and tetra[benzo]porphyrazine, and two oxygen (O2−) ions with probable oxidation state VI of Co, which is unknown for this element at the present time, was shown. Data on the structural parameters are presented. It was shown that CoN4 chelate nodes as well as all metal-chelate and non-chelate cycles in each of these complexes, were strictly planar. Besides, the bond angles formed by two donor nitrogen atoms and a Co atom were close or equal to 90°, while the bond angles formed by donor atoms N, Co, and O, in most cases, albeit insignificantly, differed from this value. Good agreement between the calculated data obtained using the above two versions of the DFT method was found. Standard thermodynamic parameters of formation (standard enthalpy ΔH0f, 298, entropy S0f, 298 and Gibbs’s energy ΔG0f, 298) for the indicated complexes were presented too.

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Preparation and properties of β-ketosulphones of 5-nitrofuran series. Study of transfer of electronic effects through sulphone group

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19820617 ◽

1982 ◽

Vol 47 (2) ◽

pp. 617-621 ◽

Cited By ~ 2

Author(s):

Dana Polakovičová ◽

Adolf Jurášek ◽

Vladimír Kvasnička

Keyword(s):

Linear Dependence ◽

Quantum Chemical ◽

Nmr Spectra ◽

Chemical Shifts ◽

Electronic Effects ◽

H Nmr ◽

Physical Measurements ◽

Hammett Constants ◽

Series Study ◽

Proton Chemical Shifts

A series of 2-(5-nitro-2-furyl)-2-oxoethylarylsulphones have been synthesized by reaction of 5-nitro-2-bromoacetylfuran with sodium p-X-benzenesulphinates (where X = H, CH3, OCH3, CH3CONH, NH2, N(CH3)2, Cl, NO2) and used for a study of transfer of electronic effects of the substituent through SO2 group. The found linear dependence between the proton chemical shifts in 1H NMR spectra (and pKa values of the CH2 group) and the Hammett constants of the substituents proves the existence of the transfer through SO2 group. The results of physical measurements were compared with the data obtained by quantum-chemical calculations using the EHT method.

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Quantum chemical modeling of the olefin oxidation in the triplet state

10.3390/ecsoc-19-e006 ◽

2015 ◽

Author(s):

Sergey Plehovitch ◽

Yuri Minasyan ◽

Sergei Zelentsov

Keyword(s):

Triplet State ◽

Quantum Chemical ◽

Quantum Chemical Modeling ◽

Chemical Modeling ◽

Olefin Oxidation

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Evaluation of Chemotherapeutic Activity of the Selected Bases’ Analogues of Nucleic Acids Supported by ab initio Various Quantum Chemical Calculations

Current Computer - Aided Drug Design ◽

10.2174/1573409915666190206212024 ◽

2020 ◽

Vol 16 (2) ◽

pp. 93-103 ◽

Cited By ~ 2

Author(s):

Piotr Kawczak ◽

Leszek Bober ◽

Tomasz Bączek

Keyword(s):

Biological Activity ◽

Nucleic Acids ◽

Ab Initio ◽

Quantum Chemical Calculations ◽

Quantum Chemical ◽

Structural Parameters ◽

Principal Component ◽

Polarizable Continuum Model ◽

Activity Data ◽

Qsar Models

Background: Pharmacological and physicochemical classification of bases’ selected analogues of nucleic acids is proposed in the study. Objective: Structural parameters received by the PCM (Polarizable Continuum Model) with several types of calculation methods for the structures in vacuo and in the aquatic environment together with the huge set of extra molecular descriptors obtained by the professional software and literature values of biological activity were used to search the relationships. Methods: Principal Component Analysis (PCA) together with Factor Analysis (FA) and Multiple Linear Regressions (MLR) as the types of the chemometric approach based on semi-empirical ab initio molecular modeling studies were performed. Results: The equations with statistically significant descriptors were proposed to demonstrate both the common and differentiating characteristics of the bases' analogues of nucleic acids based on the quantum chemical calculations and biological activity data. Conclusion: The obtained QSAR models can be used for predicting and explaining the activity of studied molecules.

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Prebiotic Route to Thymine from Formamide—A Combined Experimental–Theoretical Study

Molecules ◽

10.3390/molecules26082248 ◽

2021 ◽

Vol 26 (8) ◽

pp. 2248

Author(s):

Lukáš Petera ◽

Klaudia Mrazikova ◽

Lukas Nejdl ◽

Kristyna Zemankova ◽

Marketa Vaculovicova ◽

...

Keyword(s):

Formic Acid ◽

Quantum Chemical ◽

Prebiotic Chemistry ◽

Theoretical Study ◽

Reaction Pathway ◽

Hydrolysis Product ◽

Current Paper ◽

Reaction Conditions ◽

Chemical Modeling ◽

Chemistry Research

Synthesis of RNA nucleobases from formamide is one of the recurring topics of prebiotic chemistry research. Earlier reports suggest that thymine, the substitute for uracil in DNA, may also be synthesized from formamide in the presence of catalysts enabling conversion of formamide to formaldehyde. In the current paper, we show that to a lesser extent conversion of uracil to thymine may occur even in the absence of catalysts. This is enabled by the presence of formic acid in the reaction mixture that forms as the hydrolysis product of formamide. Under the reaction conditions of our study, the disproportionation of formic acid may produce formaldehyde that hydroxymethylates uracil in the first step of the conversion process. The experiments are supplemented by quantum chemical modeling of the reaction pathway, supporting the plausibility of the mechanism suggested by Saladino and coworkers.

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Quantum Chemical Studies and Electrochemical Investigations of Polymerized Brilliant Blue-Modified Carbon Paste Electrode for In Vitro Sensing of Pharmaceutical Samples

Chemosensors ◽

10.3390/chemosensors9060135 ◽

2021 ◽

Vol 9 (6) ◽

pp. 135

Author(s):

Pattan-Siddappa Ganesh ◽

Sang-Youn Kim ◽

Savas Kaya ◽

Rajae Salim ◽

Ganesh Shimoga ◽

...

Keyword(s):

Electrochemical Sensor ◽

Carbon Paste Electrode ◽

Quantum Chemical ◽

Electrochemical Sensing ◽

Quantum Chemical Modeling ◽

Brilliant Blue ◽

Carbon Paste ◽

Chemical Modeling ◽

The Real ◽

Paste Electrode

To develop an electrochemical sensor for electroactive molecules, the choice and prediction of redox reactive sites of the modifier play a critical role in establishing the sensing mediating mechanism. Therefore, to understand the mediating mechanism of the modifier, we used advanced density functional theory (DFT)-based quantum chemical modeling. A carbon paste electrode (CPE) was modified with electropolymerization of brilliant blue, later employed for the detection of paracetamol (PA) and folic acid (FA). PA is an analgesic, anti-inflammatory and antipyretic prescription commonly used in medical fields, and overdose or prolonged use may harm the liver and kidney. The deficiency of FA associated with neural tube defects (NTDs) and therefore the quantification of FA are very essential to prevent the problems associated with congenital deformities of the spinal column, skull and brain of the fetus in pregnant women. Hence, an electrochemical sensor based on a polymerized brilliant blue-modified carbon paste working electrode (BRB/CPE) was fabricated for the quantification of PA and FA in physiological pH. The real analytical applicability of the proposed sensor was judged by employing it in analysis of a pharmaceutical sample, and good recovery results were obtained. The potential excipients do not have a significant contribution to the electro-oxidation of PA at BRB/CPE, which makes it a promising electrochemical sensing platform. The real analytical applicability of the proposed method is valid for pharmaceutical analysis in the presence of possible excipients. The prediction of redox reactive sites of the modifier by advanced quantum chemical modeling-based DFT may lay a new foundation for researchers to establish the modifier–analyte interaction mechanisms.

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