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X-ray single crystal structure and spectroscopic and photophysical parameters of the titled compound were studied. The titled compound shows thermal stability prior to melting at 126.17 [degrees]C with [DELTA]H value of 109.991 12J[g.sup.-1]. Photophysical parameters include singlet electronic absorption, molar absorption coefficient, oscillator strength, and dipole moment of electronic transition, fluorescence spectra, excited state lifetime, and fluorescence quantum yield for 1-((E)-2-phenylethenyl)-2-(4-(2-((E)-2-phenylethenyl) phenoxy) butoxy) (PPPBB) in different solvents. PPPBB displays a little change in maximum absorption and emission spectra with solvent polarity, indicating a slight change in dipole moment of dye molecules upon excitation. The dipole moments' ([DELTA][mu]) difference between the excited and ground states was obtained from the Lippert-Mataga method. Ground and electronic excited states' geometric optimization was performed using density functional theory (DFT) and time-dependent density functional theory (time dependent-DFT), complemented with spectral findings. A good agreement between theoretical data and experimental observations was found. The net photochemical quantum yield ([[phi].sub.c]) of PPPBB dye was calculated in various solvents. Key words: 1-((E)-2-phenylethenyl)-2-(4-(2-((E)-2-phenylethenyl) phenoxy) butoxy) benzene, 1-(E)-styryl-2-(4-(2-(E)-styrylphenoxy) butoxy) benzene, alkoxy bridged styryl benzene, X-ray single crystal structure, density functional theory TD-DFT, photophysical parameters, photochemical quantum yield, 1. Introduction Fluorescent moieties linked by flexible spacers are a very important class of compounds due to their potential application in nucleic acid staining and detection of nucleic acids in [...]

Objectives: Examining the cumulative evidence from randomized controlled trials (RCTs), evaluating the use of pharmacological agents for the treatment of COVID‐19 infections in patients with critical illness. Data Sources: Databases Medline, Embase, Web of Science, Scopus, CINAHL, and Cochrane. Study Selection: Inclusion criteria were RCTs that enrolled patients with confirmed or suspected COVID‐19 infection who are critically ill. Only RCTs that examined therapeutic agents against one another or no intervention, placebo, or standard of care, were included. Data Extraction: Pairs of reviewers extracted data independently. Outcomes of interest included the overall reported mortality defined as either the ICU mortality, hospital mortality, mortality within 28 days or mortality within 90 days. Data Synthesis: A total of 40 studies (11,613 patients) evaluated 50 therapeutic intervention arms divided into five main therapy categories; steroids, antiviral medications, immunomodulators, plasma therapies [intravenous immunoglobulins (IVIG), convalescent plasma and/or, therapeutic plasma exchange], and therapeutic anticoagulation. Immunomodulators was the only group with possible mortality benefit, risk ratio (RR) 0.83 (95% CI 0.73; 0.95), with nonsignificant heterogeneity (I2 = 8%, p = 0.36). In contrast, the other therapy groups showed no significant impact on mortality, as indicated by their respective pooled RRs: steroids [RR 0.91 (95% CI 0.82; 1.01), I2 = 31%], antiviral medications [RR 1.11 (95% CI 0.82; 1.49), I2 = 57%], plasma therapies [RR 0.77 (95% CI 0.58; 1.01), I2 = 36%], and anticoagulation [RR 1.06 (95% CI 0.95; 1.18), I2 = 0%]. Conclusions: This meta‐analysis highlights both the heterogeneity and a lack of benefit from therapies evaluated during the COVID‐19 pandemic. Many of the RCTs were developed based on limited observational data. Future RCTs investigating pharmaceutical interventions in critically ill patients during pandemics need to be designed based on better evidence. [ABSTRACT FROM AUTHOR]

In the present study, 5-arylidene rhodanine derivatives 3a–f, N-glucosylation rhodanine 6, S-glucosylation rhodanine 7, N-glucoside rhodanine 8 and S-glucosylation 5-arylidene rhodanines 13a–c were synthesised and screened for cytotoxicity against a panel of cancer cells with investigating the effective molecular target and mechanistic cell death. The anomers were separated by flash column chromatography and their configurations were assigned by NMR spectroscopy. The stable structures of the compounds under study were modelled on a molecular level, and DFT calculations were carried out at the B3LYP/6-31 + G (d,p) level to examine their electronic and geometric features. A good correlation between the quantum chemical descriptors and experimental observations was found. Interestingly, compound 6 induced potent cytotoxicity against MCF-7, HepG2 and A549 cells, with IC50 values of 11.7, 0.21, and 1.7 µM, compared to Dox 7.67, 8.28, and 6.62 µM, respectively. For the molecular target, compound 6 exhibited topoisomerase II inhibition and DNA intercalation with IC50 values of 6.9 and 19.6 µM, respectively compared to Dox (IC50 = 9.65 and 31.27 µM). Additionally, compound 6 treatmnet significantly activated apoptotic cell death in HepG2 cells by 80.7-fold, it induced total apoptosis by 34.73% (23.07% for early apoptosis, 11.66% for late apoptosis) compared to the untreated control group (0.43%) arresting the cell population at the S-phase by 49.6% compared to control 39.15%. Finally, compound 6 upregulated the apoptosis-related genes, while it inhibted the Bcl-2 expression. Hence, glucosylated rhodanines may serve as a promising drug candidates against cancer with promising topoisomerase II and DNA intercalation. [ABSTRACT FROM AUTHOR]

Substituted thiocarbohydrazones were synthesized to study their complexation capability towards Cu(I), Co(II), and Ni(II) salts. The Cu(I) complexes showed ligation of one mole of Cu(I)Br to one of the synthesized ligands to form a cationic–anionic metal complex. Co(II) and Ni(II) complexes were determined due to the chelating of equal equivalents of both ligands and metal salts to form monodentate metal dihalogenated complexes. Metal complexes were characterized by mass spectrometry, IR, NMR, UV spectra, and elemental analyses. Theoretical calculations were performed using density functional theory (DFT) at the B3LYP level with 6–31 + G(d) and LANL2DZ basis sets to access reliable results to the experimental values. The calculations were performed to obtain the optimized molecular geometry, charge density distribution, extent of distortion from regular geometry, the HOMO (highest occupied molecular orbital), the LUMO (lowest unoccupied molecular orbital), the molecular electrostatic potential (MEP), reactivity index (ΔE), dipole moment (D), global hardness (η), softness (σ), electrophilicity index (ω), and chemical potential. The calculations confirmed that the investigated complexes have a reliable geometry, agreeing with the experimental observation. [ABSTRACT FROM AUTHOR]

Two-dimensional quantitative structure-activity relationship (2D-QSAR) models are useful in understanding how chemical structure is related to the biological activity of natural and synthetic chemicals. Also, they could be usefully employed for designing newer and better therapeutics. A 2D-QSAR study was performed for 52 compounds of a series of thiophenyl quinolines and α-asarone derivatives as potential hypocholesterolemic inhibitors using different types of physicochemical descriptors, which correlated significantly with the activity. Linear QSAR models were developed using multiple linear regression, where the genetic algorithm (genetic function approximation technique) was adopted for selecting the most appropriate descriptors. The results are discussed on the basis of regression data and the cross-validation technique. Model A is the best 2D-QSAR model describing the inhibition efficiency of HMG-CoA reductase with cross-validated squared correlation coefficient ([Q.sup.2] = 0.700) and the squared correlation coefficient ([R.sup.2] = 0.752), which is able to describe 70% of the variance in the experimental activity. The good agreement between the experimental and the predicted values of pIC50 (micromoles per litre) (R = 0.876) confirms the reliability and the predictability of the proposed model. The results obtained from the present QSAR study explained the importance of the electronic, structural, spatial, and electrotopological descriptors in enhancing the biological activity of the investigated inhibitors. Key words: 2D-QSAR, genetic function approximation technique, HMG-CoA reductase. Des modeles de relations quantitatives structure-activite bidimensionnelles (RQSA-2D) sont utiles pour comprendre comment une structure chimique est reliee a l'activite biologique des produits chimiques naturels ou de synthese. De plus, elles peuvent etre utilisees avec succes pour mettre au point de nouveaux et meilleurs medicaments. On a effectue une etude RQSA-2D sur 52 composes d'une serie de derives de thiophenylquinoleines et α-asarones comme inhibiteurs potentiels hypocholesterolemiques utilisant divers types de descripteurs physicochimiques qui avaient une correlation significative avec l'activite. On a developpe des modeles RQSA en faisant appel a la regression lineaire multiple dans laquelle on a adopte l'algorithme genetique (technique de l'approximation de la fonction genetique) pour choisir les descripteurs les plus appropries. On discute des resultats sur la base de donnees de regression et de la technique de la validation croisee. Le Modele A est le meilleur modele RQSA-2D pour decrire l'efficacite de l'inhibition de la reductase de la reductase de la HMG-CoA avec un coefficient de correlation a validation croisee au carre ([Q.sup.2] = 0,700) et un coefficient de correlation au carre ([R.sup.2] = 0,752) qui peut decrire 70% de la variance dans l'activite experimentale. Le bon accord entre les valeurs predites et les valeurs experimentales de pIC50 (micromoles par litre) (R = 0,876) confirme la capacite de predire et la fiabilite du modele propose. Les resultats obtenus dans la presente etude de RQSA permettent d'expliquer les descripteurs electroniques, structuraux, spatiaux et electrotopologiques permettant d'augmenter l'activite biologique des inhibiteurs etudies. [Traduit par la Redaction] Mots-cles: RQSA-2D, technique de l'approximation de la fonction genetique, reductase de la HMG-CoA., Introduction Hypercholesterolemia is major health problem and is well recognized as a primary risk factor in atherosclerotic diseases and coronary heart disease. One approach to reduce hypercholesterolemia is to use [...]

It was shown that polyethylene glycol molecules act as good corrosion inhibitors. Quantum chemical simulation showed the effect of molecular weight on studying polymers with repeating units 1, 2, 3, 4, and 5 and also polymers with high molecular weights with repeating units 10, 20, and 30. Using the density functional theory at the B3LYP/6-31G+(d,p) basis set level, ab initio calculations using the HF/6-31G+(d,p) and semi-empirical PM3 methods were performed on polyethylene glycol to investigate the correlation between its molecular structure and the corresponding inhibition efficiency. The calculated parameters include the highest occupied molecular orbital, the lowest unoccupied molecular orbital, the separation energy ([increment of E]), the dipole moment (/μ), the softness (σ), the fraction of electrons transferred from the inhibitor to the metal surface ([increment of N]), the electronegativity (χ), the hardness (η), and the total negative charge. Furthermore, the adsorption energies of the inhibitors with the aluminum (1 1 1) surface were studied using the molecular dynamic method. A good correlation between the theoretical data and the experimental results was found. Key words: inhibition of corrosion, aluminum, polyethylene glycol, quantum chemical parameters, molecular dynamics. Il a ete montre que les molecules de poly(ethyleneglycol) agissent comme de bons inhibiteurs de la corrosion. Des simulations de chimie quantique montrent que l'effet du poids moleculaire sur l'etude des polymeres comportant 1, 2, 3, 4 et 5 unites fondamentales ainsi que sur ceux de produits de poids moleculaires plus eleves comportant 10, 20 et 30 unites fondamentales. On a fait appel a des calculs effectues sur le poly(ethyleneglycol) a l'aide de la theorie de la fonctionnelle de la densite au niveau B3LYP/6-31G+(d,p) de la theorie, de calculs ab initio utilisant un ensemble HF/6-31G+(d,p) et a des methodes semi-empiriques PM3 pour etudier la correlation entre sa structure moleculaire et l'efficacite correspondante d'inhibition. Les parametres calcules comprennent l'orbitale moleculaire haute occupee, l'orbitale moleculaire basse vacante, l'energie de separation ([increment of E]), le moment dipolaire (/μ), la douceur (σ), la fraction d'electron transferee de l'inhibiteur a la surface metallique ([increment of N]), l'electronegativite (χ), la durete (η) et la charge negative totale. De plus, on a etudie les energies d'absorption des inhibiteurs avec la surface de l'aluminium (111) en faisant appel a la methode de la dynamique moleculaire. On a observe une bonne correlation entre les resultats experimentaux et les valeurs theoriques. [Traduit par la Redaction] Mots-cles: inhibition de la corrosion, aluminium, poly(ethyleneglycol), parametres de chimie quantique, dynamique moleculaire., Introduction Aluminum has a remarkable economic and industrial importance owing to its low cost, light weight, and high thermal and electrical conductivity. The most important feature of aluminum is its [...]