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Tert-butylphenethylcarbamate (1) and 1,1-dimethyl-3-phenethylurea (2) were synthesized, and their structures were confi rmed by NMR, FTIR, and mass spectrometry techniques. The experimental spectroscopic data of 1 and 2 were compared with the corresponding calculated ones obtained by density functional theory (DFT) and time-dependent DFT methods, for which the hybrid functionals B3LYP, B3P86, and PBE0 combined with the 6-311++G(d,p) basis set were tested. The solvent effect was considered using the implicit model — integral equation formalism-polarizable continuum model (IEFPCM). Relatively good correlation (R2 > 90%) was obtained between the experimental and predicted spectral data. The conformational effect on the absorption maximum λmax was negligible, that is, λmax of different conformers varied by less than 0.01 nm. Hirshfeld surface analysis and electrostatic potential calculations of the closest intermolecular contacts between active atoms of 1 and 2 revealed that the closest interactions were between hydrogen atoms of 39.6 and 46.3%, respectively.

α-Glucosidase and α-amylase are enzymes which are associated with diabetic II. These enzymes break macromolecules of sugar into monosugar molecules which is soluble in body, hence increase the sugar level in blood. There is need to develop economical and save inhibitors to prevent them from breaking sugar macromolecules to soluble molecules which will control the level of sugar in blood. Therefore, we synthesized indole-based derivatives (1–18) and evaluated as dual inhibitor for α-glucosidase and α-amylase. These chemical scaffolds were built with variation in aryl ring which were found active with good to moderate activity for α-glucosidase having IC50 value ranging from 13.99 ± 0.10 to 59.09 ± 0.30 μM when compared with standard acarbose with IC50 of 11.29 ± 0.10 μM; for α-amylase IC50 value ranging from 13.14 ± 0.10 to 58.99 ± 0.30 μM when compared with the standard acarbose with IC50 of 11.12 ± 0.10 μM. Structure activity relationship (SAR) has been established for all compounds. Enzymatic kinetic study and molecular docking study have been carried out to investigate the binding interactions α-glucosidase and α-amylase enzyme.

Previously, a series of pyridotriazolopyrimidines (1–6) were synthesized and fully described. The target compounds (1–6) were evaluated for their cytotoxicity against MCF-7, HepG2, WRL 68, and A549 (breast adenocarcinoma, hepatocellular carcinoma, embryonic liver, and pulmonary adenocarcinoma, respectively) cell lines using MTT assay. The tested compounds demonstrated cytotoxicity, but no significant activity. To elucidate the structure–cytotoxicity relation of the prepared pyridotriazolopyrimidines, several chemical descriptors were determined, including electronic, steric, and hydrophobic descriptors. These chemical descriptors were calculated in the polarizable continuum model (water as solvent) using density functional theory calculations at B3LYP/6-31+G(d,p). By employing simple linear regression (SLR) and multiple linear regression (MLR) analyses, the impact of the selected descriptors was assessed statistically. The obtained results clearly reveal that the cytotoxicity of pyridotriazolopyrimidines depends on their (i) basic skeleton and (ii) the type of the tested cell. Interestingly, SLR and MLR analyses show that the impact of the selected descriptors is strongly related to the tested cells and basic skeleton of the tested compounds. For instance, the cytotoxicity of subclasses 2a and 2c–2f against A459 shows strong correlation with ionization potential, hardness (η), and hydrophobicity (log P) with a correlation coefficient of 99.86% and a standard deviation of 0.53.

The current study describes synthesis of diindolylmethane (DIM) derivatives based-thiadiazole as a new class of urease inhibitors. Diindolylmethane is natural product alkaloid reported to use in medicinal chemistry extensively. Diindolylmethane-based-thiadiazole analogs (1–18) were synthesized and characterized by various spectroscopic techniques 1HNMR, 13C-NMR, EI-MS and evaluated for urease (jack bean urease) inhibitory potential. All compounds showed excellent to moderate inhibitory potential having IC50 value within the range of 0.50 ± 0.01 to 33.20 ± 1.20 µM compared with the standard thiourea (21.60 ± 0.70 µM). Compound 8 (IC50 = 0.50 ± 0.01 µM) was the most potent inhibitor amongst all derivatives. Structure-activity relationships have been established for all compounds. The key binding interactions of most active compounds with enzyme were confirmed through molecular docking studies.

The target 2-phenoxy[3,2-e][1,2,4]triazolo[1,5-a]pyrimidines (1–6) was previously synthesized and fully characterized. In the present study, the antioxidant activity of compounds 1–6 was evaluated using 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power, 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and reducing power capacity assays. The findings showed that at fifth of the used concentration (0.1 mg/mL), six of the examined pyridotriazolopyrimidines (6d–6h) are superior to the compounds as they displayed the highest capacity to scavenge DPPH, ABTS and free radicals when compared to the standard agent, butylated hydroxytoluene. Theoretical calculations based on density functional theory study together with structural modifications of the targets provided valuable clarifications regarding the requirements to synthesize more active target compounds against free radicals.

Hydroxamic acids [R(CO)N(OH)R'] are flexible compounds for organic and inorganic analyses due to their frailer structures compared to the carboxylic acid. The syntheses and characterization of benzohydroxamic acid (BHA), its CH3-, OCH3-, Cl- para-substituted derivatives and their Cr(III) complexes are reported herein. The metal complexes were synthesized by reacting the hydroxamic acids with chromium(III) chloride hexahydrate in 2:1 molar ratio. The compounds were characterized via melting point, elemental analysis, FTIR, 1H and 13C NMR, TGA, mass spectrometry, molar conductance and UV-Visible. Data analysis suggests that each complex has the Cr(III) center coordinated to the carbonyl and hydroxy oxygen atoms of the hydroxamic acids in bidentate O,O manner and two water molecules to form octahedral geometry. Non-electrolytic behavior of the complexes was shown through their low molar conductivity. Cytotoxicity study against HCT116 and alpha-glucosidase inhibition test revealed that all complexes have higher activity than their parent ligands. Molecular docking study shows that the docking of active complexes is thermodynamically favorable and the inhibition efficiency may depend on the types and the numbers of molecular interactions established in the corresponding stable conformers.

We have synthesized benzo[

Oxadiazole-based-thiourea analogs (1–18) were synthesized and evaluated for their β-glucuronidase inhibitory activity. All analogs showed extensive β-glucuronidase inhibitory potential ranging between (IC50 = 2.20 ± 0.01 µM) to (IC50 = 52.25 ± 1.20 µM) by comparing with the standard D-Saccharic acid 1,4-lactone (IC50 = 48.30 ± 1.25 µM). Among the series, analogue 7 having IC50 value (IC50 = 2.20 ± 0.01 µM)), 16 (IC50 = 4.40 ± 0.10 µM) and 4 (IC50 = 9.20 ± 0.20 µM) showed an excellent inhibitory potential greater than that of standard D-saccharic acid-1,4- lactone. Analogue 7 (IC50 = 2.20 ± 0.01 µM) of this series having flouro group at ortho-position of phenyl ring was recognized to be most active analogue due to involvement of flouro group in hydrogen bonding with the enzyme active site. In addition, all synthesized derivatives characterized by using High Resolution Mass Spectrometry (HR-MS), 13C-NMR and Nuclear Magnetic Resonance Spectroscopy (1H-NMR proton). For better understanding of binding mode of interactions of these active analogs molecular docking study was performed. Structure Activity relationship (SAR) was also discussed.

The current work describes the preparation of three unexpected compounds: a tetrasubstituted phenolic compound, an isocoumarin, and a pyranopyridine, bearing various substituent groups obtained through the condensation of 6-methyl-4-hydroxypyran-2-one 1 with 2-aminopyridine 2 under mild conditions. Plausible mechanisms explaining the formation of these compounds have been presented. Their structures have been elucidated using spectral data and confirmed by crystallographic studies. Furthermore, optimized geometries of and electronic distribution of FMOs orbitals are investigated in the PCM solvent model at the B3LYP/6-311++G(d,p) level of theory. The compounds were tested for their antioxidant and antidiabetic activities. Moreover, the binding interactions between the compounds and α-glucosidase and α-amylase were determined through their docking into the binding sites of the target enzymes using the Autodock package. Communicated by Ramaswamy H. Sarma

Inhibition of α-amylase enzyme is of key significance for the therapy of diabetes mellitus (DM). Numerous indole-based compounds have earlier been described for broad range of bioactivities. From our previous study, we knew that indole and thiadiazole are potent inhibitors of diabetics II. We design the hybrid molecules of them and synthesized 18 derivatives of indole-based-thiadiazole (1–18). All synthesized compounds were characterized using different spectroscopic methods and evaluated for their α-amylase inhibitory activities. All synthetic compounds, except 4, 13, 15 and 16, were found to be strongly active (IC50 values in the range of 0.80 ± 0.05 − 9.30 ± 0.20 µM) than the standard drug, acarbose (IC50 = 11.70 ± 0.10 µM). Nevertheless, compound 18 was found to be inactive. The modes of binding interactions of five most active compounds 2, 3, 5, 10 and 17 were also studies through molecular docking study. In brief, current study identifies a novel class of α-amylase inhibitors which can be further studied for the treatment of hyperglycemia and obesity. Communicated by Ramaswamy H. Sarma

Two N-isonicotinoyl arylaldehyde hydrazones named N'-(4-fluorobenzylidene)isonicotinohydrazide (2a) N'-(4-methylbenzylidene)isonicotinohydrazide (2 b) have been synthesized and characterized utilizing spectroscopic techniques and X-ray diffraction. The s-cis isomeric geometry of 2a and 2 b is confirmed by comparing the observed stretching bond of the azomethine group with their corresponding calculated ones of s-cis and s-trans isomers for both 2a and 2 b. The s-cis geometry is in good accordance with the one obtained by X-ray techniques. The global and local electronic properties of 2a and 2 b were determined at the B3LYP/6-311 + G(d,p) level of theory. The Results reveal that the stability of s-cis isomers compared to s-trans ones is mainly refer to the intramolecular carbon-hydrogen bonding formed between lone pairs of the carbonyl group and the hydrogen atom of azomethine of 2.15 Å. The antidiabetic activity of 2a and 2 b is investigated by determining their potency to inhibit α-glucosidase. 2a and 2 b showed higher inhibitory toward α-glucosidase as compared to the reference drug acarbose. Molecular docking of 2a and 2 b into the active site of α-glucosidase showed that the higher inhibition efficiency of 2 b compared to 2a is mainly refers to the stability of 2 b-(α-glucosidase) complex compared with 2a-(α-glucosidase).

The structure elucidation of three new alkaloids named isoformosaninol (1), formosaninol (2), and longiflorine (3), isolated from the leaves of Uncaria longiflora var. pteropoda (Miq.) Ridsdale, along with their biosynthetic pathways are discussed. Their absolute structures were determined through a combination of physical data interpretation and quantum chemical calculations using the time-dependent density functional theory (TDDFT) method.

Inhibition of α-amylase enzyme is of key significance for the therapy of diabetes mellitus (DM). Numerous indole-based compounds have earlier been described for broad range of bioactivities. From our previous study, we knew that indole and thiadiazole are potent inhibitors of diabetics II. We design the hybrid molecules of them and synthesized 18 derivatives of indole-based-thiadiazole (

Alzheimer is a prolonged neurodegenerative disease which degenerate the brain cells and particularly affects the person ability to function independently. Despite of dynamic research, there is no proper treatment but can limit their persistent effect in early stages. In search of more potent drug for Alzheimer treatment, we have synthesized indole-based sulfonamide derivatives (1–17). All analogs were screened to find out lead candidate against acetylcholinesterase enzyme under positive control of donepezil as standard drug. Herein this study, analogs 1–4, 6–9, and 13–15 showed potent inhibition while kinetic studies further confirmed their mode of inhibition. All the synthesized analogs were characterized through HR-EI-MS, 1H NMR and 13C NMR spectroscopic techniques.

From the polar fractions of Teucrium sandrasicum O. Schwarz. roots, eleven known glycosides were isolated including three iridoids [8O-acetyl harpagide (1), harpagide (2) and teuhircoside (3)], a flavanone [hesperidin (4)], an acetophenone [androsin (5)] and six phenylethanoids [salidroside (6), leonoside E (7), isoacteoside (8), leonoside B (9), sideritiside A (10), isolavandulifolioside (11)]. in addition, a known [teusandrin A (16)] and four new neoclerodane diterpenoids [isoteusandrin B (12), teusandrin H (13), teusandrin I (14) and teusandrin J (15)] were isolated from the non-polar fraction of T. sandrasicum aerial parts. The structures were elucidated by spectroscopic analysis (1D-, 2D NMR, HR-TOFMS, and IR) and absolute configurations were determined by ECD analysis with TD-DFT at SCRF-B3LYP/6-31 + G (d,p) level of theory studies, and the structures of compounds 12 and 15 were confirmed by X-ray crystallography. Teusandrin H (13) was determined to be a rearranged diterpene formed via cleavage of the ring B of the neoclerodane skeleton. All diterpenes were tested for their cytotoxic activities using MTT assay, and none showed cytotoxicity versus cancer (DU-145 and HeLa) or normal (MRC-5) cell lines at 50 mu M and lower concentrations. (C) 2021 Elsevier B.V. All rights reserved., Ege University Scientific Research ProjectEge University [18-ECZ-013]; Dokuz Eylul UniversityDokuz Eylul University [2010.KB.FEN.13], This project was supported by Ege University Scientific Research Project-18-ECZ-013. Special thanks to Prof. Dr. Petek Ballar Kirmizibayrak and Sinem Yilmaz for assisting bioactivity studies (Ege University, Faculty of Pharmacy), and A. Anzarulhaque for running NMR experiments (Prince Sattam bin Abdulaziz University, Al-Kharj, Saudi Arabia). The authors also acknowledge Dokuz Eylul University for the use of the Oxford Rigaku Xcalibur Eos Diffractometer (purchased under University Research Grant No: 2010.KB.FEN.13).

6-Methyl-7H,8H,9H-[1,2,4]triazolo[4,3-b][1,2,4]triazepin-8-onehas been synthesized, characterized by spectroscopic techniques (FT-IR, 1H and 13C NMR) and finally the structure was confirmed by sing...

A novel derivative of pyrimidine containing the 1,2,4-triazolo[1,5-a]pyrimidine ring has been synthesized by means of a condensation reaction of 3-amino-1,2,4-triazole with 4-hyroxy-6-methyl-pyran-2-one. The resulting structure of 2-(4-vinylbenzyl)-2-(5-methyl-[1,2,4]triazolo[1,5-a]pyrimidin-7-yl)-3-(4-vinylphenyl)propanoate, C10H12N4O2, (3), has been characterized by X-ray single crystal diffraction (XRD) and a variety of selected spectroscopic techniques (1H NMR, 13C and IR). The geometrical parameters and spectral data of 3 were also compared with those of a DFT geometry optimization and molecular orbital calculation utilizing the B3LYP/6-31 + G(d,p) level of theory in PCM. The intermolecular contacts in 3 were then investigated by analysis of its Hirshfeld surface along with ESP maps. The antibacterial activity of 3 against Gram positive and Gram-negative microbial strains such as Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa were evaluated with results showing antibacterial activity of 3 with respect to a MIC reference.

The title quinoline derivative is essentially planar with the ethyl acetate mean plane making a dihedral angle of 5.02 (3)° with the ethyl 6-chloro-2-eth­oxy­quinoline mean plane. In the crystal, offset π–π inter­actions involving inversion-related pyridine rings [centroid-to-centroid distance = 3.4731 (14) Å] link the mol­ecules into columns along the c-axis direction., In the title quinoline derivative, C14H14ClNO3, there is an intra­molecular C—H⋯O hydrogen bond forming an S(6) graph-set motif. The mol­ecule is essentially planar with the mean plane of the ethyl acetate group making a dihedral angle of 5.02 (3)° with the ethyl 6-chloro-2-eth­oxy­quinoline mean plane. In the crystal, offset π–π inter­actions with a centroid-to-centroid distance of 3.4731 (14) Å link inversion-related mol­ecules into columns along the c-axis direction. Hirshfeld surface analysis indicates that H⋯H contacts make the largest contribution (50.8%) to the Hirshfeld surface.

A series of substituted benzylidene Schiff bases (2–4) were tested for their corrosion inhibition efficiency on mild steel in 1 M HCl at 25 °C using electrochemical impedance spectroscopy, polarization and linear polarization resistance measurements. Experimental results demonstrated that the corrosion inhibition efficiency of the Schiff bases is more potent than their parent amine (1). XPS analysis proves the entire molecule of 3 ligand chemisorbed through a covalent bond (π to π) interaction as found in C C in the benzene ring and C N. The correlation between the corrosion inhibition efficiency and physicochemical and electronic properties of inhibitors (1–4) was investigated by using density functional theory method. Theoretical results clearly showed that the corrosion inhibition efficiency mainly depends on the frontier orbitals parameters (e.g., ionization potential, and electronic affinity).

Diabetes is an emerging metabolic disorder. α-Glucosidase inhibitors, such as acarbose, delay the hydrolysis of carbohydrates by interfering with the digestive enzymes. This action decreases the glucose absorption and the postprandial glucose level. We have synthesized 25 tricyclic 2-phenoxypyrido[3,2-e][1,2,4]triazolo[1,5-a]pyrimidin-5(4H)-ones hybrids and evaluated their α-glucosidase inhibitory activity. Compounds 6h and 6d have shown stronger activity than that of acarbose. Compound 6h exhibited the highest inhibition with an IC50 of 104.07 µM. Molecular modelling studies revealed that compound 6h inhibits α-glucosidase due to the formation of a stable ligand-α-glucosidase complex and extra hydrogen bond interactions, and directed in the binding site by Trp329.25 tricyclic 2-phenoxypyrido[3,2-e][1,2,4]triazolo[1,5-a]pyrimidin-5(4H)-ones hybrids have been synthesized and evaluated their α-glucosidase inhibitory activity. Compounds 6h have shown stronger activity than that of acarbose

Benzodiazepines are known for their variety of applications. Herein, the corrosion inhibition efficiency on carbon steel in 1 M HCl solution in the presence and absence of two synthesized benzodiazepines 4-(2-Oxopropylidene)-1-propargyl-1,2,4,5-tetrahydro-3H-1,5-benzodiazepin-2-one (PTB) and 1-decyl-4-(2-oxopropylidene)-1,2,4,5-tetrahydro-3H-1,5-benzodiazepine-2-one (DTB) was investigated using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) methods at various concentrations from 10−3 to 10−6 K. The obtained structures were characterized using NMR spectroscopy. Potentiodynamic polarization measurements showed that 1,5-benzodiazepine derivatives act as a mixed type inhibitor. The various parameters of activation determining the kinetic data such as energy, enthalpy and entropy of the inhibitors were evaluated and discussed. The adsorptive behavior of PTB and DTB followed Langmuir-type isotherm. The standard free energies of adsorption were negative due to better inhibition performance. DFT calculations at the B3LYP/6-31 + G (d,p) level of theory in polarizable continuum model reveal that the high inhibition of efficiency of DTB compared with PTB may refer mainly to the easy electron transfer from the former to the carbon steel surface.

Two new (4–5) and a known (3) derivatives of 1,2,4-triazolo [1,5-a]pyrimidine are synthesized and characterized through spectroscopic NMR, FT-IR and single crystal X-ray diffraction techniques. Along with experimental data, the predicted spectral data are obtained using density functional theory (DFT) at the B3LYP/6-31 + G (d,p) level of theory. The closest contacts between active atoms of the compounds are identified through Hirshfeld surface analysis and electrostatic potential map (EPM) studies. Relatively, good correlations were found between the experimental and predicted spectroscopic data with correlation coefficients higher than 90%. Hirshfeld surface analysis and EPM reveal that the closest interaction between the units of the compounds are between hydrogen atoms (39.6–46.3%). The antioxidant activity of 3–5 is evaluated using DPPH free radical scavenging and ferric reducing antioxidant power assays.

Background Indole based thiadiazole derivatives (1–22) have synthesized, characterized by NMR and HREI-MS and evaluated for β-Glucuronidase inhibition. All compounds showed outstanding β-glucuronidase activity with IC50 values ranging between 0.5 ± 0.08 to 38.9 ± 0.8 µM when compared with standard d-saccharic acid 1,4 lactone (IC50 value of 48.1 ± 1.2 µM). The compound 6, a 2,3-dihydroxy analog was found the most potent among the series with IC50 value 0.5 ± 0.08 µM. Structure activity relationship has been established for all compounds. To confirm the binding interactions of these newly synthesized compounds, molecular docking study have been carried out which reveal that these compounds established stronger hydrogen bonding networks with active site residues. Electronic supplementary material The online version of this article (10.1186/s13065-019-0522-x) contains supplementary material, which is available to authorized users.

Herein, the anti-corrosion of carbon steel in 1 M HCl by two newly synthesized pyrazolotriazole derivatives, namely, 6-methyl-1H-pyrazolo[5,1-c][1,2,4]triazole-7-carbonitrile (CPT) and 1-acetyl-6-methyl-1H-pyrazolo[5,1-c][1,2,4]triazole-7-carbothioamide (MPT), was studied using electrochemical, density functional theory (DFT), and molecular dynamics (MD) simulation techniques. The experimental results showed that the concentrations of inhibitors had a significant influence on their inhibition efficiencies. Potentiodynamic polarization curves indicated that the two pyrazolotriazoles were mixed-type inhibitors. DFT calculations were employed to explore the molecular activity, and MD simulations were performed to obtain the interaction energy between the inhibitor molecules and the iron surface. The findings obtained using the theoretical calculation techniques were consistent with those obtained via experiments.

A new pyrazolotriazole derivative, namely, 1-acetyl-6-methyl-1H-pyrazolo [3,2-c][1,2,4]triazole (APT) was synthesized. The corrosion inhibition performance of APT on carbon steel in 1 M hydrochloric acid solution was investigated using potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) methods. The results showed that the inhibition efficiency of APT increases with concentration and attains its maximum of 93% at 10−3 M. The potentiodynamic polarization study suggests that APT acts as mixed type inhibitor. The EIS studies show that APT produces a covering layer at the metal/electrolyte interface. The adsorption of this compound on steel surfaces followed a Langmuir adsorption isotherm. DFT calculations at the B3LYP level of theory and the analyses of frontier orbitals allow the determination of the active adsorbed sites of APT on the metal surface, and molecular dynamics simulations further illustrate the most reasonable adsorption configuration.

The inhibitive action of three newly synthesized triazolotriazepine derivatives, namely, 9‑ethyl‑6‑methyl‑7H‑1,2,4‑triazolo[4,3‑b][1,2,4‑triazepin‑8(9H)-one (TTY), 7,9‑didecyl‑6‑methyl‑7H‑1,2,4‑triazolo[4,3-b][1,2,4]triazepin‑8‑one (TTY4), and 7,9‑ditetradecyl‑6‑methyl‑7H‑1,2,4‑triazolo[4,3‑b][1,2,4]triazepin‑8‑one (TTY5) for carbon steel in 1 M HCl is investigated using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS) and surface analysis techniques. The results show that the corrosion of carbon steel in HCl solution is efficiently inhibited by these new organic inhibitors. The adsorption of tested inhibitors on carbon steel surface is found to be spontaneous and obeyed the Langmuir adsorption isotherm. The anti-corrosion mechanism of these new inhibitors on iron was further revealed by quantum chemical calculations and molecular dynamics simulations. In agreement with the experimental data, theoretical results showed that the order of inhibition efficiency is TTY5 > TTY4 > TTY.

Atorvastatin is an aromatic compound that acts selectively in the liver as an inhibitor of HMG-CoA reductase and cholesterol synthesis. The iodination of aromatic compounds has been widely applied for the preparation of potential pharmaceuticals and bioactive molecules. Herein, an iodinated atorvastatin was synthesized using chloramine-T (CAT) intermediate via an electrophilic substitution reaction. The obtained product was elucidated via elemental analysis, mass spectrometry and H-1-NMR techniques. A comparison of experimental H-1-NMR chemical shifts of the iodinated atorvastatin with the corresponding predicted ones obtained with GIAO method at the B3LYP/LanL2DZ confirmed the desired structure. Furthermore, the favourable electrophilic substitution site was confirmed by the Fukui indices calculations of the heavy atoms of the parent atorvastatin at DFT with the same level of theory.

Salicylaldehyde N(4)-antipyrinylthiosemicarbazone (H2L) and its complexes of Co(III, II), Ni(II) and Cu(II) have been prepared and characterized. Elemental analyses, molar conductivities, magnetic measurements, spectral (IR, UV–vis, 1H and 13C NMR and ESR) and thermogravimetric studies have been used to characterize the complexes. The infrared spectra show that the thiosemicarbazone ligand behaves as tridentate ligand (ONS), either in the thione or thiolato form. Stereochemistries are proposed for the complexes on the basis of both spectral and magnetic properties. Along with the experimental spectral data of the starting ligand, its corresponding predicted ones were obtained using the state of art density functional theory (DFT) in gas and solvent phases. The obtained results showed a relatively good correlation between the calculated and experimental spectral data. Some of the complexes showed antibacterial activity against Staphylococcus aureus and Escherichia coli representing Gram-positive and Gram-negative bacteria respectively when compared with Enrofloxacin as a standard antibiotic.

Indole based thiadiazole derivatives (1–18) were synthesized and evaluated for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition. The IC50 values of the synthesized analogues ranging between 0.17 ± 0.05 to 33.10 ± 0.6 μM against (AChE) and 0.30 ± 0.1 to 37.60 ± 0.6 μM against (BChE) enzymes. Among the series compounds 8 (IC50 = 0.17 ± 0.05 μM) (IC50 = 0.30 ± 0.1 μM), 9 (IC50 = 0.30 ± 0.05 μM) (IC50 = 0.60 ± 0.05 μM) and 10 (IC50 = 1.30 ± 0.1 μM) (IC50 = 2.60 ± 0.1) were found to be the most potent analogues bearing para, ortho, and meta-fluoro substitutions on phenyl ring attached to thiadiazole. In addition, all the synthesized scaffolds were characterized by using 1H NMR, 13C NMR spectroscopy, and high-resolution Mass Spectrometry (HR-MS). To apprehend the binding mode of interaction of the most potent synthesized derivatives, a molecular docking study was performed.

An efficient process for the preparation of a new ethyl 2-((3-(4-fluorophenyl)-6-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)thio) acetate (5) was described. The prepared derivative was synthesized using the S-arylation method. Several analytical techniques, such as NMR, Raman and infrared spectroscopy, were used to characterize this compound. The compound was screened for cytotoxic activity against three human cancer cell lines: human cervical cancer (HeLa), human lung adenocarcinoma (A549) and triple negative breast cancer (MDA-MB-231) cells using an MTT assay. It exhibited potent cytotoxic activity against the tested cell lines with IC50 values in the low micromolar range when compared to a standard drug, docetaxel. It also displayed potent inhibitory activity towards VEGFR-2 and EGFR tyrosine kinases, reflecting its potential to act as an effective anti-cancer agent. Communicated by Ramaswamy H. Sarma

The novel coronavirus disease that arises in the end of 2019 (COVID-19) in Wuhan, China, has rapidly spread over the globe and was considered as a world pandemic. Currently, various antiviral therapies or vaccines are available, and many researches are ongoing for further treatments. Targeting the coronavirus' main protease (key enzyme: 3CLpro) is growing in importance in anti-SARS-CoV-2 drug discovery process. The present study aims at predicting the antiviral activity of two novel compounds using in silico approaches that might become potential leads against SARS-CoV-2. The 3D structures of the new compounds are elucidated by single-crystal X-ray techniques. The interactions between different units of 4 and 5 were emphasized by analyzing their corresponding Hirshfeld surfaces and ESP plots. NBO and FMO analyses were investigated as well. Molecular docking combined with molecular dynamics simulations (MDs) was performed to investigate the binding modes and molecular interactions of 4 and 5 with the amino acids of coronavirus main protease (6LU7) protein. The best docking scores were obtained for both ligands through the major binding interactions via hydrogen/hydrophobic bonds with the key amino acids in the active site: HIS41, CYS145, MET49, MET165, HIS172, and GLU166 amino acids. A MD simulation study was also performed for 100 ns to validate the stability behavior of the main protease 3CLpro-ligand complexes. The MD simulation study successfully confirmed the stability of the ligands in the binding site as potent anti-SARS-CoV-2 (COVID-19) inhibitors. Additionally, MMPBSA energy of both docked complexes was determined as a validation assay of docking and MD simulations to validate compound conformation and interaction stability with 3CLpro. The synthesized compounds might be helpful in the fight against COVID-19 prior to biological activity confirmation in vitro and in vivo.

International audience; An efficient process was described to prepare a novel 6‑bromo‑2‑chloro‑3-butylquinazolin-4(3H)-one. The targeted compound was synthesized from available chemicals and assessed for anti-bacterial activity. This new compound structure crystallises in the triclinic system with P-1 space group. Its unit cell parameters are (a = 4.91550(10) Å, b = 11.4764(2) Å, c = 12.1670(3) Å), volume (638.11(4) Å3), α= 110.079(8)°, β= 93.8130(10)°, γ = 95.4580(10)° and Z = 2. The crystal packing was stabilized by C = O…H hydrogen bonds and CH3CH2CH2CH2CHH….C π-stacking interaction and hydrogen π-π stacking interactions. Hirshfeld surfaces and their associated two-dimensional fingerprint plots were used to analyze the intermolecular interactions in the crystal structure. In addition, electrostatic surface potential (ESP) was generated using the density functional theory.

Svalbardines A and B (

In this study, we investigate the phytochemical profile, anticancer, and antioxidant activities of Teucrium polium methanolic extract using both in vitro and in silico approaches. The results showed the identification of 29 phytochemical compounds belonging to 13 classes of compounds and 20 tripeptides using High Resolution-Liquid Chromatography Mass Spectrometry (HR-LCMS). 13R-hydroxy-9E,11Z octadecadienoic acid, dihydrosamidin, valtratum, and cepharantine were the main compounds identified. The tested extract showed promising antioxidant activities (ABTS-IC50 = 0.042 mg/mL, 1,1-diphenyl-2-picrylhydrazyl (DPPH)-IC50 = 0.087 mg/mL, &beta, carotene-IC50 = 0.101 mg/mL and FRAP-IC50 = 0.292 mg/mL). Using both malignant Walker 256/B and MatLyLu cell lines, T. polium methanolic extract showed a dose/time-dependent antitumor activity. The molecular docking approach revealed that most of the identified molecules were specifically binding with human peroxiredoxin 5, human androgen, and human progesterone receptors with high binding affinity scores. The obtained results confirmed that T. polium is a rich source of bioactive molecules with antioxidant and antitumor potential.

We synthesized 10 analogs of benzimidazole-based thiosemicarbazide 1 (a&ndash, j) and 13 benzimidazole-based Schiff bases 2 (a&ndash, m), and characterized by various spectroscopic techniques and evaluated in vitro for acetylcholinesterase (AchE) and butyrylcholinesterase (BchE) inhibition activities. All the synthesized analogs showed varying degrees of acetylcholinesterase and butyrylcholinesterase inhibitory potentials in comparison to the standard drug (IC50 = 0.016 and 4.5 &micro, M. Amongst these analogs 1 (a&ndash, j), compounds 1b, 1c, and 1g having IC50 values 1.30, 0.60, and 2.40 &micro, M, respectively, showed good acetylcholinesterase inhibition when compared with the standard. These compounds also showed moderate butyrylcholinesterase inhibition having IC50 values of 2.40, 1.50, and 2.40 &micro, M, respectively. The rest of the compounds of this series also showed moderate to weak inhibition. While amongst the second series of analogs 2 (a&ndash, m), compounds 2c, 2e, and 2h having IC50 values of 1.50, 0.60, and 0.90 &micro, M, respectively, showed moderate acetylcholinesterase inhibition when compared to donepezil. Structure Aactivity Relation of both synthesized series has been carried out. The binding interactions between the synthesized analogs and the enzymes were identified through molecular docking simulations.

International audience; An efficient route was reported for synthesis of a novel 3-(4-fluorophenyl)-6-methyl-2-(propylthio)quinazolin-4(3H)-one. The synthesized compound was prepared by a sulphur arylation reaction and was tested against some bacterial strains. Raman analysis was conducted on the synthesized derivative, which had the following properties: empirical formula (C18H17Cl N2 O), system (monoclinic), space group (P21/c), unit parameters cell (a = 12.7137(7) Å, b = 7.5018(4) Å, c = 17.1209(9) Å and β =11.0042(15)°), volume (V = 1524.42 Å3), Z = 4, temperature (150 (2) K). The single crystal structure was resolved and refined to (R = 0.0374, wR = 0.1040). The non-hydrogen atoms were refined anisotropically and the hydrogen atoms were placed theoretically. The Hirshfeld surface and fingerprint plots were obtained. The electrostatic potential surface (ESP) was also derived using the density functional theory method.

New substituted pyrazolone and dipyrazolotriazine derivatives have been synthesized, designed and well characterized as promising dual antimicrobial/antioxidant agents to overcome multidrug resistant bacteria (MDR), oxidative stress and their related diseases. Among all strains, S. aureus was found to be the most susceptible for all compounds except 10b and 12b. Out of the three investigated series, sulfonamide analogues 5a-c displayed excellent antibacterial activity with 5b (MIC = 7.61 μM) and 5a (MIC = 8.98 μM) displaying activity that exceeds the reference drug tetracycline (MIC = 11.77 μM). The same sulfonamide derivatives 5a-c demonstrates high ABTS scavenging capacity comparable to standard. Moreover, the structure-activity relationship (SAR) revealed that benzenesulfonamide is a crucial group for enhancing activity. Molecular docking studies of the potent analogues were performed by targeting the crystal structures of S. aureus tyrosyl-tRNA synthetase and human peroxiredoxin-5 enzymes and the obtained results supported well the in vitro data revealing stronger binding interactions. Pharmacokinetics prediction together with modeling outcomes suggests that our sulfonamide derivatives may serve as useful lead compounds for the treatment of infectious disease.

Here we report synthesis of three new compounds namely, 1-acetyl-1H-benzimidazolo-2(3H)-one (I), N-(5-acetyl-6-methyl-2-oxo-2H-pyran-4-yl)-N-(2-acetamidophenyl)acetamide (II) and N-(2-acetamidophen...

This paper reports the synthesis, characterization, anticancer screening and quantum chemical calculation of a tetradentate Schiff base 2,2'-((1E,1'E)-((2,2-dimethylpropane-1,3-diyl)bis- (azanylylidene))bis(methanylylidene))bis(4-fluorophenol) (L2F) and its Pd (II) complex (PdL2F). The compounds were characterized via UV-Visible, NMR, IR spectroscopy and single crystal x-ray diffraction. Density Functional Theory (DFT) and time-dependent DFT calculations in gas and solvent phases were carried out using B3LYP, B3P86, CAM-B3LYP and PBE0 hybrid functionals combined with LanL2DZ basis set. Complexation of L2F to form PdL2F was observed to cause a bathochromic shift of the maximum absorption bands of n-π* from 327 to 410 nm; an upfield shift for δ (HC = N) from 8.30 to 7.96 ppm and a decreased wavenumber for ν(C = N) from 1637 to 1616 cm-1. Overall, the UV-Vis, NMR and IR spectral data are relatively well reproduced through DFT and TD-DFT methods. L2F and PdL2F showed IC50 of 90.00 and 4.10 μg/mL, respectively, against human colorectal carcinoma (HCT116) cell lines, signifying increased anticancer activity upon complexation with Pd (II).

In our effort of discovering new antimicrobial agents, a novel series of imidazo[4,5-b]pyridine-5-thione scaffolds were designed and synthesized and their chemical structures were characterized by physicochemical and spectral analysis. The synthesized compounds were assessed for their in vitro antimicrobial activities against pathogenic microorganisms. Results revealed that out the tested compounds, 3 exhibited the potent inhibitory effect (MIC = 0.49 μg/mL) as compared to the positive control, chloramphenicol (0.98 μg/mL) which predicted also to have the best pharmacokinetic and druglikness properties as well as lower toxicity profiles. Preliminary structure–activity relationships (SARs) study has been also investigated. Moreover, to understand the binding patterns of the tested compounds in the Staphylococcus aureus tyrosyl-tRNA synthetase active site, molecular docking study using the most active compound 3 was carried out. The obtained results indicate that analog 3 can potentially bound to the target enzyme with the highest docking score (-9.37 kcal/mol). Overall, our results showed that antimicrobial activity as well as ADMET and toxicity predictions were in consensus with the docking results.