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1.
Polycyclic Aromatic Compounds ; 43(3):2690-2744, 2023.
Article in English | ProQuest Central | ID: covidwho-2304288

ABSTRACT

The present study aims to provide deeper knowledge about the structural, vibrational, chemical, antimicrobial activity, molecular dynamic simulation and drug likeness of synthesized compound 4-Methoxy-N-(nitrobenzylidene)-aniline. The FT-IR and FT-Raman spectra of 4-Methoxy-N-(nitrobenzylidene)-aniline have been recorded in the powder form in the region 4000–500 cm−1 and 3500–50 cm−1. The vibrational analysis were carried out with the help of normal coordinate analysis (NCA). The molecular geometry, hydrogen bonding interaction and vibrational frequencies have been calculated using the density functional method (DFT/B3LYP) with 6-311 G (D) basis set. The natural bond orbital (NBO), atoms in molecule (AIM), and Hirshfeld surface analysis and RDG were applied to evaluate the relative strength of hydrogen bond interactions and represent their effect on the stabilities of molecular arrangements. Related molecules were compared by computation in order to understand the effect of non-bonded interactions (i.e. intermolecular and intramolecular hydrogen bonding). The HOMO and LUMO analysis was used to determine the charge transfer within the molecule. Furthermore, the in vitro antimicrobial study was carried out for the title compound against Aspergillus niger and Staphylococcus aureus. The antimicrobial activity was confirmed on the compounds with molecular docking (A.niger, S.aureus, Homosapians, Sars-Cov-19 and anticancer) studies and molecular dynamic simulation. The non-linear optical (NLO) properties were also analyzed for the molecules.

2.
Angewandte Chemie ; 135(13):1-1, 2023.
Article in English | Academic Search Complete | ID: covidwho-2269425

ABSTRACT

The resulting NIR-II PS not only enables NIR-II image-guided in vivo pulmonary coronavirus photo-ablation but also demonstrates a facile approach for the development of NIR heavy-atom-free PSs. Keywords: Coronavirus Inactivation;Intersystem Crossing;NIR-II Imaging;Photosensitizer;Triplet State EN Coronavirus Inactivation Intersystem Crossing NIR-II Imaging Photosensitizer Triplet State 1 1 1 03/15/23 20230320 NES 230320 B The relationship b between molecular configuration and charge transfer processes in near-infrared-II (NIR-II) chromophores was studied, and subsequently instructed the engineering of an efficient NIR photosensitizer (PS), as reported by Wenbo Hu, Yuliang Xiao et al. in their Research Article (e202214875). The resulting NIR-II PS not only enables NIR-II image-guided in vivo pulmonary coronavirus photo-ablation but also demonstrates a facile approach for the development of NIR heavy-atom-free PSs. [Extracted from the article] Copyright of Angewandte Chemie is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

3.
Angewandte Chemie International Edition ; 62(13):1-1, 2023.
Article in English | Academic Search Complete | ID: covidwho-2269424

ABSTRACT

The resulting NIR-II PS not only enables NIR-II image-guided in vivo pulmonary coronavirus photo-ablation but also demonstrates a facile approach for the development of NIR heavy-atom-free PSs. Keywords: Coronavirus Inactivation;Intersystem Crossing;NIR-II Imaging;Photosensitizer;Triplet State EN Coronavirus Inactivation Intersystem Crossing NIR-II Imaging Photosensitizer Triplet State 1 1 1 03/15/23 20230320 NES 230320 B The relationship b between molecular configuration and charge transfer processes in near-infrared-II (NIR-II) chromophores was studied, and subsequently instructed the engineering of an efficient NIR photosensitizer (PS), as reported by Wenbo Hu, Yuliang Xiao et al. in their Research Article (e202214875). The resulting NIR-II PS not only enables NIR-II image-guided in vivo pulmonary coronavirus photo-ablation but also demonstrates a facile approach for the development of NIR heavy-atom-free PSs. [Extracted from the article] Copyright of Angewandte Chemie International Edition is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

4.
Angewandte Chemie ; 135(13), 2023.
Article in English | ProQuest Central | ID: covidwho-2269422

ABSTRACT

Despite significant effort, a majority of heavy‐atom‐free photosensitizers have short excitation wavelengths, thereby hampering their biomedical applications. Here, we present a facile approach for developing efficient near‐infrared (NIR) heavy‐atom‐free photosensitizers. Based on a series of thiopyrylium‐based NIR‐II (1000–1700 nm) dyads, we found that the star dyad HD with a sterically bulky and electron‐rich moiety exhibited configuration torsion and significantly enhanced intersystem crossing (ISC) compared to the parent dyad. The electron excitation characteristics of HD changed from local excitation (LE) to charge transfer (CT)‐domain, contributing to a ≈6‐fold reduction in energy gap (ΔEST), a ≈10‐fold accelerated ISC process, and a ≈31.49‐fold elevated reactive oxygen species (ROS) quantum yield. The optimized SP@HD‐PEG2K lung‐targeting dots enabled real‐time NIR‐II lung imaging, which precisely guided rapid pulmonary coronavirus inactivation.

5.
Materials Science in Semiconductor Processing ; 158, 2023.
Article in English | Scopus | ID: covidwho-2256143

ABSTRACT

In this work, we have presented a comparative study on Ribavirin (RBV) drug sensing and detection on the pristine and functionalized single-wall carbon nanotubes (f-SWCNTs) by Density Functional Theory (DFT) method. The pristine and metal-doped zigzag (4,0) and (6,0) SWCNTs were first considered for the RBV adsorption. All the probable positions of RBV adsorption were investigated to find which one is energetically favourable. The topology analysis of the Quantum theory of atoms in a molecule (QTAIM) with non-covalent interactions (NCI-RDG), Frontier molecular orbitals (FMO), Density of states (DOS), and non-linear optical (NLO) analysis were carried out to understand the molecular structure, electrical, electronic and optical properties of complexes. The charge analysis indicates that charge transfer is from the adsorbed RBV to the pristine and metal-doped (4,0) and (6,0) SWCNTs. The highest values of adsorption energies for Al-, Si-doped and pristine (4,0) SWCNTs were determined as −34.688, −87.999 and −10.382 kcal/mol, respectively, whereas corresponding values for metal-doped and pristine (6,0) SWCNTs are about −43.592, −20.661 and −12.414 kcal/mol, respectively. The results suggest that those bare and metal-doped (4,0) SWCNTs and (6,0) Si-SWCNTs can serve as promising sensors in practical applications to detect, recognize and carrier RBV drug for its medicinal drug delivery applications. Based on the NLO properties of (6,0) Si-SWCNTs and pristine (6,0) SWCNT (with an acceptable recovery time of 279s and first hyper polarizability value of β = 229.25 × 10−30 cm5 esu−1), those nanotubes may be possible candidates to be used as the optoelectronic sensor for RBV drug. The appropriate short length of nanotubes was obtained. © Elsevier Ltd

6.
Applied Organometallic Chemistry ; 37(3):1-28, 2023.
Article in English | Academic Search Complete | ID: covidwho-2247764

ABSTRACT

The 5‐(4‐aryl azo)‐8‐hydroxyquinolines (L1–L3) and their metal complexes with Ni2+ and Zn2+ have been produced. Various spectroscopic techniques have been employed to analyze the ligand and complexes. The structures of the prepared compounds have been confirmed by Fourier transform infrared (FT‐IR), proton nuclear magnetic resonance (1H NMR), molar conductance, magnetic measurements, thermal gravimetric and differential thermal analyses (TG and DTA), and electronic transition. The FT‐IR spectra showed that the ligands are coordinated to the metal ions in a bidentate manner with donor sites of the azomethine‐N and phenolic‐OH. The FT‐IR and UV–Visible spectra were compared with the calculated results and showed a good agreement. The mass spectra concluded that the ligands' molecular weights and the calculated estimated m/z values match well. The complexes contain coordinated and hydrated water as confirmed by the TG results. The complexes are tetrahedral, trigonal bipyramid, and octahedral geometrical structures and act as non‐electrolytes in dimethylformamide (DMF) solvent. Using density functional theory (DFT) at the B3LYP level of theory and the 6‐311G** basis set for the C, H, N, Cl, and O atoms and the LANL2DZ basis set for the Ni and Zn atoms. Natural bond orbital (NBO) analysis was used to compute and describe the natural charge population and precise electronic configuration. The small energy gap between HOMO and LUMO energies suggests that charge transfer occurs within Ni2+ and Zn2+ complexes. The first‐order hyperpolarizability (β) of the complexes and the anisotropy of polarizability (α) values show promising optical properties. The electronic transitions of the prepared complexes were computed by time‐dependent density functional theory (TD‐DFT/PCM) with the B3LYP method using a 6‐31G** basis set. The ethanol polarizable continuum model (PCM) was used to simulate the solvent effect. Utilizing a computer virtual screening technique through molecular docking, the anticipation of binding of 8‐quinolinolazodye derivatives and their complexes with human CORONA virus protein (PDB ID: 5epw) was done. [ FROM AUTHOR] Copyright of Applied Organometallic Chemistry is the property of John Wiley & Sons, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

7.
Chemical Engineering Journal ; 451, 2023.
Article in English | Scopus | ID: covidwho-2245424

ABSTRACT

In the wake of the recent COVID-19 pandemic, antibiotics are now being used in unprecedented quantities across the globe, raising major concerns regarding pharmaceutical pollution and antimicrobial resistance (AMR). In view of the incoming tide of alarming apprehensions regarding their aftermath, it is critical to investigate control strategies that can halt their spread. Rare earth vanadates notable for their fundamental and technological significance are increasingly being used as electrochemical probes for the precise quantification of various pharmaceutical compounds. However, a comprehensive study of the role of the cationic site in tailoring the response mechanism is relatively unexplored. Hence, in this work we present a facile hydrothermal synthesis route of rare earth vanadates TVO4 (T = Ho, Y, Dy) as efficient electrocatalyst for the simultaneous detection of nitrofurazone (NF) and roxarsone (RX). There appears to be a significant correlation between T site substitution, morphological and the electrochemical properties of rare earth metal based vanadates. Following a comparative study of the electrochemical activity, the three rare-earth vanadates were found to respond differently depending on their composition of T sites. The results demonstrate that Dy-based vanadate displays increased electrical conductivity and rapid charge transfer characteristics. Thus, under optimal reaction conditions DyVO4- based electrodes imparts outstanding selectivity towards the detection of NF and RX with an extensive detection window of NF = 0.01–264 µM & RX = 0.01–21 µM and 36–264 µM and low detection limit (0.002, 0.0009 µM for NF and RX, respectively). In real-time samples, the proposed sensor reveals itself to be a reliable electrode material capable of detecting residues such as NF and RX. © 2022 Elsevier B.V.

8.
Applied Organometallic Chemistry ; 2022.
Article in English | Scopus | ID: covidwho-2208883

ABSTRACT

The 5-(4-aryl azo)-8-hydroxyquinolines (L1–L3) and their metal complexes with Ni2+ and Zn2+ have been produced. Various spectroscopic techniques have been employed to analyze the ligand and complexes. The structures of the prepared compounds have been confirmed by Fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H NMR), molar conductance, magnetic measurements, thermal gravimetric and differential thermal analyses (TG and DTA), and electronic transition. The FT-IR spectra showed that the ligands are coordinated to the metal ions in a bidentate manner with donor sites of the azomethine-N and phenolic-OH. The FT-IR and UV–Visible spectra were compared with the calculated results and showed a good agreement. The mass spectra concluded that the ligands' molecular weights and the calculated estimated m/z values match well. The complexes contain coordinated and hydrated water as confirmed by the TG results. The complexes are tetrahedral, trigonal bipyramid, and octahedral geometrical structures and act as non-electrolytes in dimethylformamide (DMF) solvent. Using density functional theory (DFT) at the B3LYP level of theory and the 6-311G** basis set for the C, H, N, Cl, and O atoms and the LANL2DZ basis set for the Ni and Zn atoms. Natural bond orbital (NBO) analysis was used to compute and describe the natural charge population and precise electronic configuration. The small energy gap between HOMO and LUMO energies suggests that charge transfer occurs within Ni2+ and Zn2+ complexes. The first-order hyperpolarizability (β) of the complexes and the anisotropy of polarizability (α) values show promising optical properties. The electronic transitions of the prepared complexes were computed by time-dependent density functional theory (TD-DFT/PCM) with the B3LYP method using a 6-31G** basis set. The ethanol polarizable continuum model (PCM) was used to simulate the solvent effect. Utilizing a computer virtual screening technique through molecular docking, the anticipation of binding of 8-quinolinolazodye derivatives and their complexes with human CORONA virus protein (PDB ID: 5epw) was done. © 2022 John Wiley & Sons Ltd.

9.
Chem Eng J ; 452: 138894, 2023 Jan 15.
Article in English | MEDLINE | ID: covidwho-2003913

ABSTRACT

The recent outbreak of Covid-19 guarantees overconsumption of different drugs as a necessity to reduce the symptoms caused by this pandemic. This triggers the proliferation of pharmaceuticals into drinking water systems. Is there any hope for access to safe drinking water? Photocatalytic degradation using artificial Z-scheme photocatalysts that has been employed for over a decade conveys a prospect for sustainable clean water supply. It is compelling to comprehensively summarise the state-of-the-art effects of Z-scheme photocatalytic systems towards the removal of pharmaceuticals in water. The principle of Z-scheme and the techniques used to validate the Z-scheme interfacial charge transfer are explored in detail. The application of the Z-scheme photocatalysts towards the degradation of antibiotics, NSAIDs, and bacterial/viral inactivation is deliberated. Conclusions and stimulating standpoints on the challenges of this emergent research direction are presented. The insights and up-to-date information will prompt the up-scaling of Z- scheme photocatalytic systems for commercialization.

10.
J Mol Liq ; 363: 119878, 2022 Oct 01.
Article in English | MEDLINE | ID: covidwho-1937005

ABSTRACT

Hydrocortisone (termed as D1) and dexamethasone (termed as D2) are corticosteroids currently used to treat COVID-19. COVID-19 is a disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Exploring additional chemical properties of drugs used in the treatment protocols for COVID-19 could help scientists alike improve these treatment protocols and potentially even the vaccines (i.e., Janssen, Moderna, AstraZeneca, Pfizer-BioNTech). In this work, the charge-transfer (CT) properties of these two corticosteroids (D1 and D2) with two universal acceptors: 7,8,8-tetracyanoquinodimethane (termed as TCNQ) and fluoranil (termed as TFQ) in five different solvents were investigated. The examined solvents were MeOH, EtOH, MeCN, CH2Cl2, and CHCl3. The CT interactions formed stable corticosteroid CT complexes in all examined solvents. Several spectroscopic parameters were derived, and the oscillator strength (f) and transition dipole moment (µe.g. ) values revealed that the interaction between the investigated corticosteroids with TCNQ acceptor is much stronger than their interaction with TFQ acceptor. The CT interactions were proposed to process via n â†’ π* transition.

11.
Journal of the Indian Chemical Society ; : 100605, 2022.
Article in English | ScienceDirect | ID: covidwho-1907309

ABSTRACT

The interaction of chlorothiazide (CH) as donor (D) with picric acid (PA) and iodine (I2) as π- and σ-acceptors (A), respectively, gives charge-transfer (CT) complexes as a final products. The reaction of donor and acceptors were studied spectrophotometrically. The complexes are generally of the n-π* and n-σ* types, with the ground state wave function primarily characterized by the non-bonding structure. For the micro determination of chlorothiazide using picric acid and iodine as acceptors, the ideal conditions encouraging the formation of complexes are thoroughly explored. It was discovered that the stoichiometry of the molecular structure is 1:1 (D:A). The equilibrium constant and the molar extinction coefficient were calculated using Benesi-Hildebrand and its modifications. DFT/TD-DFT calculations with B3LYP/LanL2DZ and 6-311G++ level of theory were used to provide comparable theoretical data along with electronic energy gap of HOMO→LUMO. Molecular docking calculations have been performed between CT complexes and Covid-19 protease (6LU7) to study the interaction between them and their inhibitory effect.

12.
Journal of Molecular Liquids ; : 119206, 2022.
Article in English | ScienceDirect | ID: covidwho-1819573

ABSTRACT

Quinine (QN), chloroquine (CQ), and hydroxychloroquine (HCQ) belong to the 4-aminoquinoline family. QN was used to treat the Spanish Flu, while CQ and HCQ are under consideration for the treatment of COVID-19. This work aimed to investigate the charge-transfer (CT) interaction between QN compound with five acceptor molecules: iodine crystals (A1), 7,7,8,8-tetracyanoquinodimethane (A2), 2,3-dichloro-5,6-dicyano-p-benzoquinone (A3), chloranilic acid (A4), and tetrafluoro-1,4-benzoquinone (A5). The experimental results indicated that QN formed stable and vividly colored CT complexes with these acceptors. Strong color changes occurred upon complexation in both liquid and solid forms. The analytical findings suggest that QN reacted with the A2, A3, A4 and A5 acceptors at a 1:1 molar ratio and a 1:2 ratio with A1 acceptor. The charge migration occurred from QN to A1 via the formation of a tri-iodide complex, while the charge migration occurred from QN to A2, A3, A4, and A5 acceptors through an n → π* interaction.

13.
J Mol Struct ; 1263: 133104, 2022 Sep 05.
Article in English | MEDLINE | ID: covidwho-1796297

ABSTRACT

Remdesivir (REM) is an adenosine triphosphate analog antiviral drug that has received authorization from European Commission and approval from the U.S. Food and Drug Administration for treatment of coronavirus disease 2019 (Covid-19). This study, describes, for the first time, the synthesis of a novel charge transfer complex (CTC) between REM, as electron donor, with chloranilic acid (CLA), as π electron acceptor. The CTC was characterized using different spectroscopic and thermogravimetric techniques. UV-visible spectroscopy ascertained the formation of the CTC in methanol via formation of a new broad absorption band with maximum absorption peak (λmax) at 530 nm. The molar absorptivity (ε) of the complex was 3.33 × 103 L mol-1 cm-1 and its band gap energy was 1.91 eV. The stoichiometric ratio of REM:CLA was found to be 1:1. The association constant of the complex was 1.11 × 109 L mol-1, and its standard free energy was 5.16 × 104 J mole-1. Computational calculation for atomic charges of energy minimized REM was conducted, the site of interaction on REM molecule was assigned and the mechanism of the reaction was postulated. The solid-state CTC was further characterized by FT-IR and 1H NMR spectroscopic techniques. Both FT-IR and 1H NMR confirmed the formation of the CTC and its structure. The reaction was adopted as a basis for developing a novel 96-microwell spectrophotometric method (MW-SPA) for REM. The assay limits of detection and quantitation were 3.57 and 10.83 µg/well, respectively. The assay was validated, and all validation parameters were acceptable. The assay was implemented successfully with great precision and accuracy to the determination of REM in its bulk form and pharmaceutical formulation (injection). This assay is simple, economic, and more importantly, has high throughput property. Therefore, the assay can be valuable for routine in quality control laboratories for analysis of REM's bulk form and pharmaceutical injection.

14.
J Mol Liq ; 357: 119092, 2022 Jul 01.
Article in English | MEDLINE | ID: covidwho-1778379

ABSTRACT

COVID-19 is the disease caused by a novel coronavirus (CoV) named the severe acute respiratory syndrome coronavirus 2 (termed SARS coronavirus 2 or SARS-CoV-2). Since the first case reported in December 2019, infections caused by this novel virus have led to a continuous global pandemic that has placed an unprecedented burden on health, economic, and social systems worldwide. In response, multiple therapeutic options have been developed to stop this pandemic. One of these options is based on traditional corticosteroids, however, chemical modifications to enhance their efficacy remain largely unexplored. Obtaining additional insight into the chemical and physical properties of pharmacologically effective drugs used to combat COVID-19 will help physicians and researchers alike to improve current treatments and vaccines (i.e., Pfizer-BioNTech, AstraZeneca, Moderna, Janssen). Herein, we examined the charge-transfer properties of two corticosteroids used as adjunctive therapies in the treatment of COVID-19, hydrocortisone and dexamethasone, as donors with 2,3-dichloro-5,6-dicyano-p-benzoquinone as an acceptor in various solvents. We found that the examined donors reacted strongly with the acceptor in CH2Cl2 and CHCl3 solvents to create stable compounds with novel clinical potential.

15.
National Technical Information Service; 2021.
Non-conventional in English | National Technical Information Service | ID: grc-753698

ABSTRACT

Dr. Eliot Young of Southwest Research institute (SwRI) is the PI of a proposal entitled: Testbed for High-Acuity Imaging and Stable Photometry and Image-Motion Compensation (THAI-SPICE). The main goal of this larger project is to build and demonstrate a fine-pointing system for stratospheric payloads to enable diffraction-limited performance by balloon-borne telescopes. This proposal from MIT Lincoln Laboratory (LL) was as a Co-Investigation of this Sub-Orbital Mission, within the Astronomy and Physics Research and Analysis Program (APRA) and was to furnish to NASA an electronic camera using orthogonal-transfer charge-coupled devices (OTCCD), with a high charge-transfer efficiency (CTE), to stabilize the images acquired by a balloon-borne telescope flying at approximately 120,000 ft. The camera, which has high sensitivity and low noise, will be integrated with the SwRI telescope as government-furnished equipment and will be able to integrate photons arriving from dim stars and other objects over long periods of time. This will enable the acquisition of images with jitter of less than 1 arcsecond. It will be a significant advance for both NASA and astronomy, in general, to have balloon-borne, diffraction-limited telescopes that are free of atmospheric aberrations operating at a much lower cost than similar-aperture satellite-borne telescopes. MIT LL provided the CCID77 and built the prototype camera, in which it was housed, to SwRI through NASA, in the summer of 2020. The balloon launch was to take place in the fall of 2020, but was delayed until the fall of 2021, due to the COVID-19 pandemic and its effect on the NASA balloon launch schedule. The camera has worked well on the ground and has been integrated into the balloon payload. This has completed the obligations of MIT LL to the program.

16.
Chemistry of Materials ; 2021.
Article in English | Scopus | ID: covidwho-1713093

ABSTRACT

Owing to the pandemic of Coronavirus disease 2019 (COVID-19), the demands on ultracold-chain logistics have rapidly increased for the storage and transport of mRNA vaccines. Herein, we report a soluble luminescent thermometer based on thermally activated dual-emissions of Mn2+-alloyed 2D perovskite quantum wells (QWs). Owing to the Mn2+ alloying, the binding energy of perovskite QW exciton is reduced from 291 to 100 meV. It facilitates the dissociation of excitons into free charge carriers, which are then transferred and trapped on Mn2+. The temperature-dependent charge transfer efficiency can be tuned from 8.8% (-93 °C) to 30.6% (25 °C), leading to continuous ratiometrical modulation from exciton-dominated violet emission to Mn2+-dominated orange emission. The highest sensitivity (1.44% per K) is approximately twice that of the Mn2+-doped chalcogenide quantum dots. Taking advantage of highly reversible color switching, Mn2+-alloyed QWs provide an economical solution to monitor the ultracold-chain logistics of the COVID-19 vaccine. © 2022 American Chemical Society.

17.
New Journal of Chemistry ; : 11, 2022.
Article in English | Web of Science | ID: covidwho-1612218

ABSTRACT

With the global pandemic caused by the COVID-19 virus, vast and widespread research on drug therapy is in progress around the world. In this respect, one of the most widely studied drugs is Favipiravir. Our aim in this work was to study the adsorption behavior of Favipiravir drug on the surface of first-row transition metals (Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn) decorated on boron phosphide (B12P12) nanocage to develop an excellent drug carrier through the density functional theory (DFT) and time dependent-density functional theory (TD-DFT). The interaction of the drug with different transition metals decorated B12P12 nanodusters was studied in order to examine the most suitable nanocage for the drug carrier. A narrow band gap with red-shifting in absorption spectrum was observed for the drug-adsorbed metal-decorated B12P12 nanodusters. Excellent adsorption energies were found in Favipiravir-adsorbed metal-decorated nanodusters (E-ad = 151 to 212 kJ mol(-1)). Negative values of Gibbs free energy and enthalpy of the reaction suggested that the adsorption of the drug on metal-decorated B12P12 nanodusters is an exothermic and spontaneous phenomenon. Different geometrical parameters such as molecular electrostatic potential, the alignment of frontier molecular orbitals, Q(NBO), dipole moment, and global indices of reactivity are considered for drug adsorption. Results of different analyses indicated that metal decoration on B12P12 nanodusters is an efficient approach for Favipiravir adsorption. Thus, these systems may facilitate us in the future for COVID-19 therapy.

18.
J Mol Struct ; 1251: 132010, 2022 Mar 05.
Article in English | MEDLINE | ID: covidwho-1536963

ABSTRACT

An innovative charge-transfer complex between the Schiff base 2-((2-hydroxybenzylidene) amino)-2-(hydroxymethyl) propane-1,3-diol [SAL-THAM] and the π-acceptor, chloranilic acid (CLA) within the mole ratio (1:1) was synthesized and characterized aiming to investigate its electronic transition spectra in acetonitrile (ACN), methanol (MeOH) and ethanol (EtOH) solutions. Applying Job`s method in the three solvents supported the 1:1 (CLA: SAL-THAM) mole ratio complex formation. The formation of stable CT- complex was shown by the highest values of charge-transfer complex formation constants, KCT, calculated using minimum-maximum absorbance method, with the sequence, acetonitrile > ethanol > methanol DFT study on the synthesized CT complex was applied based on the B3LYP method to evaluate the optimized structure and extract geometrical and reactivity parameters. Based on TD-DFT theory, the electronic properties, 1H and 13C NMR, IR, and UV-Vis spectra of the studied system in different solvents showing good agreement with the experimental studies. MEP map described the possibility of hydrogen bonding and charge transfer in the studied system. Finally, a computational approach for screening the antiviral activity of CT - complex towards SARS-CoV-2 coronavirus protease via molecular docking simulation was conducted and confirmed with molecular dynamic (MD) simulation.

19.
J Mol Liq ; 340: 117224, 2021 Oct 15.
Article in English | MEDLINE | ID: covidwho-1415661

ABSTRACT

Finding a cure or vaccine for the coronavirus disease (COVID-19) is the most pressing issue facing the world in 2020 and 2021. One of the more promising current treatment protocols is based on the antibiotic azithromycin (AZM) alone or in combination with other drugs (e.g., chloroquine, hydroxychloroquine). We believe gaining new insight into the charge-transfer (CT) chemistry of this antibiotic will help researchers and physicians alike to improve these treatment protocols. Therefore, in this work, we examine the CT interaction between AZM (donor) and tetracyanoethylene (TCNE, acceptor) in either solid or liquid forms. We found that, for both phases of starting materials, AZM reacted strongly with TCNE to produce a colored, stable complex with 1:2 AZM to TCNE stoichiometry via a n → π* transition (AZM → TCNE). Even though both methodologies yielded the same product, we recommend the solid-solid interaction since it is more straightforward, environmentally friendly, and cost- and time-effective.

20.
J Mol Liq ; 335: 116250, 2021 Aug 01.
Article in English | MEDLINE | ID: covidwho-1198990

ABSTRACT

Investigating the chemical properties of molecules used to combat the COVID-19 pandemic is of vital and pressing importance. In continuation of works aimed to explore the charge-transfer chemistry of azithromycin, the antibiotic used worldwide to treat COVID-19, the disease resulting from infection with the novel SARS-CoV-2 virus, in this work, a highly efficient, simple, clean, and eco-friendly protocol was used for the facile synthesis of charge-transfer complexes (CTCs) containing azithromycin and three π-acceptors: 7,7,8,8-tetracyanoquinodimethane (TCNQ), 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), and tetrafluoro-1,4-benzoquinone (TFQ). This protocol involves grinding bulk azithromycin as the donor (D) with the investigated acceptors at a 1:1 M ratio at room temperature without any solvent. We found that this protocol is environmentally benign, avoids hazardous organic solvents, and generates the desired CTCs with excellent yield (92-95%) in a straightforward means.

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