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• Thirteen carbazole-thiazole-Schiff base hybrids were synthesized and the structures of the synthesized compounds by different spectral data (IR, 1H NMR, and HRMS). • Agar disc diffusion method was employed to evaluate the antimicrobial activities of the synthesized analogues. • The antioxidant activities of the synthesized compounds were determined by DPPH radical scavenging assay. • In silico toxicity, drug-likeness, and drug-score properties were determined to demonstrate the oral bioavailability of the compounds. • Molecular docking and dynamics studies were performed to endorse the experimental outcomes. Conventional and microwave irradiation (MWI) methods were applied to synthesize a series of thirteen carbazole-thiazole-Schiff base hybrids (2a-2m). MWI assisted synthesis was a benign approach to green synthesis on account of its miniscule reaction time and use of solvent. The structures of the synthesized derivatives were confirmed by means of spectral analytical data. All the compounds were evaluated for dual biological potency i.e., antimicrobial and antioxidant activity. The tested analogues had shown some modest antimicrobial activity and compounds 2f and 2i exhibited higher antioxidant activity compared to standard ascorbic acid. Oral bioavailability and adverse effects of the new entities were considered from druglikeness descriptors, having no violation of Lipinski's rule of five and Veber's rule for the synthesized compounds except for 2i, 2l , and 2m. The compounds which exhibited relatively high activity were explored further for molecular docking studies to understand the mode of binding interactions with the receptor protein. Molecular dynamics (MD) simulation was further studied to predict the stability of selective compounds inside the receptors which was well agreed with in vitro results and antioxidant value. [Display omitted] [ABSTRACT FROM AUTHOR] more...

• Synthesis of silver nanoparticles and their integration into bullfrog skin. • Characterization of modified and unmodified bullfrog skin using XRD, SEM, EDS, and ICP-OES techniques. • Significant inhibitory effects on common pathogens (Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans). • It was identified that 1 % and 1.5 % concentrations of silver nanoparticles were most effective for antimicrobial activity, suggesting optimal levels for potential medical applications. • Potential of silver nanoparticle-modified bullfrog skin as an innovative and effective wound dressing material. This research explores the synthesis of silver nanoparticles and their incorporation into bullfrog skin for potential use as a wound dressing. The study addresses the need for wound dressings that exhibit biocompatibility, low cytotoxicity, superior biodegradability, and antimicrobial activity. Silver nanoparticles were synthesized using silver nitrate and sodium citrate solutions and integrated into bullfrog skin at varying concentrations (0%, 0.5%, 1%, and 1.5%). The modified and unmodified bullfrog skin samples were characterized using dynamic light scattering(DLS), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Energy Dispersive Spectroscopy (EDS). Antimicrobial analyses were conducted to assess the efficacy of the modified skin against common pathogens, including Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli , and Candida albicans. The results demonstrated that samples containing 1% and 1.5% silver nanoparticles exhibited significant inhibitory effects on all tested microorganisms. This indicates that these concentrations are optimal for antimicrobial activity, suggesting the potential of silver nanoparticle-modified bullfrog skin as an innovative and effective wound dressing material. [Display omitted] [ABSTRACT FROM AUTHOR] more...

• Reactivity of (E)−1-(2‑bromo-4-methylphenyl)−3-(4-bromophenyl)prop‑2-en-1-one with nitrogen nucleophile's and active methylene. • Antimicrobial and antioxidant activities of bromo heterocyclic derivatives'. • Docking simulation of synthesized compounds with different proteins. • Optimization of synthesized compounds utilized DFT/B3LYP-6311(G) basis set and determination of their physical descriptors. In this elucidation, we synthesized different heterocyclic compounds through (E)-1-(2‑bromo-4-methylphenyl)-3-(4-bromophenyl)prop‑2-en-1-one(3) which is synthesized from the aldol condensation between 4-bromobenzaldehyde and 1-(2‑bromo-4-methylphenyl)ethan-1-one in the basic condition in excellent yield. Furthermore, the chalcone 3 showed also varied activity with nitrogen nucleophiles and active methylene and displayed different heterocyclic rings which were confirmed through different spectral analyses such as FT-IR, 1HNMR, 13CNMR, and mass spectrum. Moreover, the synthesized heterocyclic exhibited antimicrobial properties against various microbial strains (Gram-positive, Gram-negative, and fungal strains) through the well diffusion methodology and comparable with Ampicillin and Mycostatin drugs. Furthermore, the synthesized compounds demonstrated various radical scavenger properties and antioxidant activities. These biological analyses demonstrated various binding energies and interactions with proteins and were validated through molecular docking studies using distinct protein pockets interaction. Additionally, the Frontier Molecular Orbitals (FMO), which are physical descriptors of optimal structures that are connected with biological evaluations and demonstrate the activities of these compounds due to presence of two bromine atom which effect on electron deficiency and increase its action which examined via the DFT/B3LYP/6-311G basis set. [Display omitted] [ABSTRACT FROM AUTHOR] more...

Methyl α- D -mannopyranoside (MDM, 1) was subjected to direct unimolar lauroylation in pyridine at low temperature (0-20 °C) with lauroyl chloride. It showed regioselectivity at C-6 position and furnished 6- O -lauroyl-α- D -mannopyranoside 3 in 59% yield. For structural elucidation as well as to get newer mannopyranosides of biological importance compound 3 was converted to eight newer 2,3,4-tri- O -acylates 4 - 11 in good yields. PASS predication and antimicrobial studies showed that these compounds possess better antifungal activities than that of antibacterial functionalities. ADMET, PASS prediction and antimicrobial study have performed to evaluate the pharmacokinetic and microbial properties of MDM esters. Image 1 • Regioselective unimolar lauroylation of MDM yields 6- O -lauroates. • Reactivity order in MDM at 0-20 °C is 6-OH > 2-OH,3-OH,4-OH. • Incorporation of octyl and lauroyl groups increases antifungal activity of MDM. • MDM lauroyl esters are more susceptible to fungi than bacteria. [ABSTRACT FROM AUTHOR] more...

• Pyrano-Coumarin 1–12 hybrids were produced through different synthetic methods. • Antimicrobial properties for all synthesized compounds were examined. • The three most powerful compounds, 3, 9, and 12 were chosen for additional research. • Antibiofilm and DNA-Gyrase inhibitory activities for all synthesized hybrids was performed. • Pharmacokinetics, drug-likeness and PAINS alerting profiles, toxicity, and docking were done. Due to their various pharmacological effects, several substituted nitrogen heterocycles containing coumarin have recently attracted a great deal of attention. Acetyl-coumarin was used in reactions with p -methoxy-benzaldehyde, malononitrile, and ordinary heating to produce compound 1 , which contains cyano-amine, allowing for the one-pot and speedy synthesis of coumarin derivatives. Ethyl cyanoacetate, triethyl orthoformate, phenyl isothiocyanate, carbon disulfide, and benzaldehyde, were used to condense compound 1 to get the corresponding chromene derivatives 2 – 15. Elemental and spectroscopic evidence was used to characterize every freshly synthesized hits. S. aureus (MRSA), P. aeruginosa, E. coli , and C. albicans were the standard strains employed in this investigation. Most of the compounds displayed moderate to high activity against all the tested species, according to the early screening results with a MIC range of 0.25 to 1024 μg/mL. When compared to the positive control, compounds 3, 6, 9, and 12 showed the greatest declining reduction in the bulk of the bacterial species' biofilm. The findings of subsequent testing on the three most powerful compounds against E. coli DNA gyrase inhibitory activity revealed that all these derivatives block DNA gyrase and hence prevent cell proliferation. Additionally, successful in silico investigations for the most active compounds were conducted. [Display omitted] [ABSTRACT FROM AUTHOR] more...

Abstract The complexes of oxovanadium(IV) with bidentate heterocyclic azo pyrazolone were synthesized and characterized by elemental analyses, IR, UV–Visible, EPR and magnetic measurements as well as thermal analysis and X-ray diffraction. Reaction of [VIVO(acac) 2 ] (where acac = acetylacetonate) in methanol with azo pyrazolones (HL n) produced mononuclear vanadium(IV) oxo complexes with general formula [VO(L n) 2 ]H 2 O. The molar conductance measurements proved that all the complexes are non-electrolytes. IR spectra showed that the ligands (HL n) acts as a monobasic bidentate ligand by coordinating via the nitrogen atom of the pyrazole ring (HN N =) and deprotonated hydroxyl O, thereby forming a square pyramidal chelating ring. Analytical data revealed that all the complexes exhibited 1:2 (metal-ligand) ratio. The thermal data confirm that the complexes have water molecule outside the coordination sphere and the complexes show similar thermogravimetric decomposition fragments which are consistent with the proposed structures. The thermodynamic parameters of VO(II) complexes are calculated using Coats–Redfern and Horowitz-Metzger methods. The optimized bond lengths, bond angles and the calculated quantum chemical parameters for VO(II) complexes (1 – 3) were investigated. Their interactions with calf thymus DNA were investigated by absorption spectra and viscosity measurements. The results suggest that these complexes bind to DNA in an intercalative mode (K b = 4.58–8.96 × 105 M−1). All VO(II) complexes (1 – 3) were evaluated against human cancer cell lines, MCF-7 and HepG-2 as compared with the positive controls in the viability assay of colchicine and vinblastine. Complex 2 (IC 50 = 30.5 ± 2.3 and 20.1 ± 1.9 μg/ml) exhibit moderate activities against the two cell lines MCF-7 and HepG-2, respectively as compared to the Colchicine (IC 50 = 17.7 ± 0.03 and 10.6 ± 0.01 μg/mL). The antimicrobial activities of VO(II) complexes were tested against gram negative bacteria (Escherichia coli) , gram positive bacteria (Staphylococcus aureus) and fungal (Candida albicans). Graphical abstract Image 10140 Highlights • Oxovanadium(IV) complexes. • Calf-thymus DNA binding studies. • Thermodynamic parameters. • Cytotoxicity, antioxidant and antimicobial activities. [ABSTRACT FROM AUTHOR] more...

Abstract A new pyrazole based 'NNO' tridentate ligand, 5-methylpyrazole-3yl-N-(2́-hydroxyphenylamine)methyleneimine, (MP z OAP) was synthesized and characterized by elemental analyses, mass, IR, 1H NMR spectral parameters. The versatile coordination mode of the ligand was established by the synthesis of Co(III), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) metal ion complexes. These complexes were characterized by elemental analyses, conductance and magnetic susceptibility measurements, UV–Vis, IR, 1H NMR spectroscopy, PXRD and thermal analysis. The structures of the ligand and complexes were also investigated using the DFT method. The ligand structure contains the coordination function of the tertiary nitrogen atom of pyrazole ring, the azomethine nitrogen and the phenolic oxygen atom, suitably spaced for chelation with a metal ion and acting as a 'NNO' tridentate donor ligand. In vitro antimicrobial activity of the reported ligand and the metal ion complexes were screened and the mode of action was also studied by scanning electron microscopy (SEM) against some pathogenic bacteria. Graphical abstract A new pyrazole containing Schiff base ligand and its Co(III), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) complexes have been synthesized & characterized. The reported NNO tridentate ligand (MP z OAP) binds with the metal ion via the tertiary nitrogen atom of pyrazole ring, the azomethine nitrogen and the phenolic oxygen atom. The structural conformation of the ligand has been established by X-ray study. The structures of the ligand and the metal ion complexes are also investigated using the DFT method. The In vitro antimicrobial activities of the ligand and the complexes have been reported and the mode of action against some pathogenic bacteria, studied by scanning electron microscopy (SEM), is shown. Image 1 Highlights • Syntheses and characterizations of a Schiff base ligand and its metal ion complexes have been reported. • X-ray study confirmed the structure of ligand molecule. The structures of complexes and ligand have also been confirmed by DFT study. • Antimicrobial screening of the compounds and the mode of cell killing activity through SEM study have been reported. [ABSTRACT FROM AUTHOR] more...

1-Arylidene-2-tetralone (2), obtained from condensation of 2-tetralone and aromatic aldehydes in acetic acid and HCl, on condensation with thiosemicarbazide in acidic and alkaline medium afforded tetrahydro-2 H -benzo[ e ]indazole-2-carbothioamide as trans (3) and cis (4) diastereoisomers of 1- H and 9b- H respectively. The synthesis of new indazolyl-thiazol-4(5 H )-ones (5) from trans isomer (3) and α-halo acids is reported. A DFT study along with single crystal X-ray diffraction data of a representative compound (5a) is presented. The chemistry of the reaction of indazole-2-carbothioamides with methyl iodide, DMAD and acetic anhydride is described. Eight newly synthesised compounds were screened for their antibacterial and antifungal activities. Some of the compounds have shown promising antimicrobial activities. [ABSTRACT FROM AUTHOR] more...

• Twelve azomethine analogs of 4-aminoantipyrine were synthesized. • Some analogs have potent antibacterial, antifungal and antioxidant activity. • Drug-likeness, ADMET properties, drug scores and secondary enzymatic targets were estimated. • Molecular docking was performed on the active site of KAS (E. coli) and CYP 51 (C. albicans) receptors. • FMO energies, global molecular reactivities, and biological properties were explored by DFT method. A series of twelve azomethine analogs (3a - l) of 4-aminoantipyrine (4-AA) were prepared and characterized using FT-IR, 1HNMR and EI mass spectrometric analysis. Analog 3f was obtained as a single crystal, and X-ray diffraction (XRD) data indicated its adoption of a trans configuration around the central azomethine (C N) group, forming monoclinic P2(1)/n symmetry. The unit cell of 3f contains four molecules, and its crystal packing is stabilized through significant intermolecular host-guest C H⋯O, C H⋯π, and π⋯π interactions, resulting in a stacked supramolecular structure. In vitro bactericidal and fungicidal screening of analogs 3a - l was performed against twelve bacterial and five fungal strains, respectively. Most of the analogs demonstrated weak to moderate antimicrobial activities, specifically 3a, 3b, 3e and 3g exhibited highest activity against S. boydii, B. megaterium; S. sonnei and E. coli , respectively and 3c, 3d and 3l showed potent fungicidal activity against A. flavus, C. albicans , and N. crassa , respectively. The results indicate that the antimicrobial potency is largely dependent on the nature of the aromatic ring linked pyrazolone moiety via azomethine (C N) group. DPPH free radical scavenging assay revealed analogs 3e, 3l, 3g, 3k, 3h and 3d had IC 50 values of 0.07, 1.19, 2.31, 2.57, 4.04 and 4.07 µg mL−1, respectively, comparable to that of the standard ascorbic acid (IC 50 = 4.10 µg mL−1). Docking simulations were conducted to elucidate the binding mode of potent antibacterial analogs (3e and 3g) and antifungal analogs (3d and 3l) within the active sites of KAS (E. coli) and CYP 51 (C. albicans) receptors, respectively. The results revealed strong binding affinities between the studied molecules and the respective proteins. All the tested analogs fulfill the condition of Lipinski's rule of five (ROF) and Veber's rule, and the calculated ADMET profile indicated favorable drug-likeness, pharmacokinetic properties, and drug scores. Ligand-based enzymatic target predictions suggest that analogs 3a-l have potential as inhibitors of kinases, enzymes, proteases, or ligands for Family A GPCR. Finally, DFT calculations using the B3LYP/6-311G(d,p) level of theory provide insights into the FMO energies, global molecular reactivity, and biological properties of the azomethine analogs of 4-AA. [ABSTRACT FROM AUTHOR] more...

• A new dopamine Schiff bases were synthesized as antimicrobial and potential anti COVID-19 agents. • The antimicrobial properties of the synthesized dopamine Schiff bases were assessed. • The chemical properties of the compounds were determined by DFT calculations. • The ADME properties of the compounds were calculated. • Molecular docking studies were performed to investigate the molecular interactions between the dopamine Schiff bases and two targets: the bacterial enzyme S. aureus and the main protease of the SARS-CoV-2 virus. In this study, Schiff bases containing dopamine were synthesized and their antimicrobial activities were investigated in vitro. What makes this study unique is the use of dopamine as a starting compound, which has not been previously explored for the synthesis of Schiff bases with acetophenone substituents. These newly synthesized compounds exhibit important pharmacological properties, and their structures have been thoroughly characterized using elemental analysis, 1H NMR, 13C NMR, and FT-IR methods. In the next phase of the study, we evaluated the antimicrobial activities of these dopamine Schiff bases against seven different bacterial and fungal isolates. Remarkably, one compound, 5NO 2 -afdop, demonstrated exceptionally high antibacterial activity (MIC: 0.078 μg/ml) against Gram-positive bacteria, namely Staphylococcus aureus and Staphylococcus epidermis. Its activity was even superior to that of the reference drugs sulfisoxazole and sulfamethoxazole (MIC: 0.312 μg/ml). This finding highlights the potential of the synthesized compound as a promising antimicrobial agent. Moreover, in-silico studies, the 5NO 2 -afdop compound shows comparable activity against the major protease of SARS-CoV-2, the virus responsible for the COVID-19 pandemic. To assess the drug-likeness of all synthesized compounds, we employed the five Lipinski rules and conducted ADME predictions. These analyses provided valuable insights into the compounds' pharmacological profiles, suggesting their potential as drug candidates.. Additionally, molecular docking studies shed light on the interactions between the synthesized compounds and their target proteins. Notably, 5NO 2 -afdop exhibited the strongest antibacterial activity against the S. aureus protein (PDB ID: 4FGD) and displayed promising antiviral activity against the SARS-CoV-2 major protease (PDB ID: 5R80). These docking results further support the potential of 5NO 2 -afdop as a dual-action compound with antibacterial and antiviral properties. [Display omitted] [ABSTRACT FROM AUTHOR] more...

• MMPs derivatives were designed, synthesized, and confirmed by using spectral analyses. • MMPs were investigated in vitro against human and plant pathogens. • Compounds 3 and 6 exhibited the best antimicrobial activity. • Molecular docking and dynamics confirmed the in vitro findings of C 3 and C6, by saving high affinity with strong interactions. • ADMET prediction show that C3 and C6 are not carcinogen nor mutagenesis. Carbohydrates are considered as biomolecules playing numerous biological roles and can act as receptors part for several microbial pathogens as well as a barrier to microbial infection. Here we synthesize five novel methyl α- D -mannopyranoside (1) analogues following regioselective acylation, where, methyl 6- O -propionyl-α- D -mannopyranoside was converted into 2,3,4-tri- O -propionyl analogues with excellent percentage of yields. Structural configurations of the synthesized methyl α- D -mannopyranoside analogues were confirmed by spectroscopic, physicochemical, and elemental study. Prediction of activity spectra for substances (PASS) and in vitro antimicrobial experiment of the methyl α- D -mannopyranoside analogues against seven human and plant pathogenic microorganisms transpired solid antibacterial and antifungal activities are studied. Most of the compounds exhibited salient antibacterial potentiality with minimum inhibitory concentration (MIC) values ranging from 0.25 µg/mL to 2.00 µg/mL and minimum bactericidal concentration (MBC) values ranging from 8.00 µg/mL to 16.00 µg/mL. The above observations were rationalized by molecular docking against Escherichia coli and Bacillus cereus (4V7S and 1KZN), Aspergillus flavus (6K3H) and Aspergillus niger (3K4Q) specific targets to search the binding affinities and different interactions of methyl α- D -mannopyranoside analogues. Compounds 3 and 6 were discovered to be the most promising for binding with the target due to their high affinity energy and the stability of the docked complexes were confirmed by molecular dynamics. Combination of in silico ADMET prediction and drug-likeness had shown assuring results for compounds 3 and 6 due to their improved kinetic parameters in terms of biological activity. Overall, the findings are encouraging for the development of novel drugs for the treatment of human and plant pathogens. [ABSTRACT FROM AUTHOR] more...

Three new copper (II) and nickel (II) complexes viz . [Cu(L) 2 ]( 1a ), [Cu(L) 2 ]( 1b ) and [Ni(L) 2 ].DMF( 2 ), where HL = 2-(( E) -(2, 4-dibromophenylimino) methyl)-4-bromophenol, have been synthesized and characterized by using various physico-chemical and spectroscopic techniques. The crystal structures of Schiff base (HL) and their metal complexes ( 1a ), ( 1b ) and ( 2 ) were determined by single crystal X-ray diffraction. IR and UV–Vis spectra and magnetic susceptibility measurements agree with the observed crystal structures. The crystallographic and spectroscopic studies confirmed four coordinate environments around the metal (II) ions. The synthesized Schiff base ligand (HL) crystallizes in the orthorhombic system of the space group Pbca . Complex ( 1a ) of HL was crystallized in the monoclinic system of the space group P 2 1 / c , a = 10.1712(9) Å, b = 10.9299(10) Å,c = 12.7684(11) Å,α = 90̊,β = 104.649(2)̊, γ = 90̊ and Z = 2 whereas complex ( 1b ) and ( 2 ) crystallized in the triclinic system of the space group P-1, a = 11.499(5)Å, b = 11.598(5)Å, c = 12.211(5)Å, α = 98.860(5), β = 115.653(5),γ = 100.906(5) and Z = 2 for ( 1b ), a = 9.080(6) Å, b = 9.545(8)Å, c = 9.545(8)Å, α = 101.43(4)º,β = 99.63(3)̊, γ = 117.71(2)º and Z = 1 for ( 2 ). The synthesized ligand (HL) was behaved as monobasic bidentate Schiff base ligand having N and O donor sites. The electron paramagnetic resonance spectra indicate a d x 2 –y 2 ground state (g || > g ⊥ > 2.0023) for ( 1a ) and ( 1b ). Copper (II) complexes display X-band EPR spectra in 100% DMSO and 77 K, giving indicating d x 2 –y 2 ground state. Superoxide dismutase-like activities of HL and its complexes were investigated by nitrobluetetrazolium chloride-DMSO assay and IC 50 values were evaluated. These complexes were also tested for their in vitro antimicrobial activities against two bacteria ( E. coli and Salmonella typhi ) and two fungi ( Pencillium , Aspergillus sp.) comparing with the Schiff base. The antimicrobial results showed that the complexes were more biologically active compounds to the Schiff base (HL). [ABSTRACT FROM AUTHOR] more...

The ternary complexes with stoichiometry [M(imda)(bipy)]·6H 2 O (M = Cu) and [M(imda)(bipy)(H 2 O)]·4H 2 O (M = Ni, Co and Mn) where H 2 imda = iminodiacetic acid and bipy = 2,2′-bipyridine, are prepared and characterized to exploit as novel antimicrobial agents and SOD mimics. The chemical structures were elucidated by IR, FAB-Mass, 1 H, 13 C NMR, EPR and spectral techniques. Single crystal X-ray and spectral studies of the complexes ( 1 ) and ( 2 ) have confirmed a square pyramidal geometry around Cu(II) ion while a saturated six coordinate (distorted octahedral) geometry around the Ni(II), Co(II) and Mn(II) ions due to the additional coordination from water. A supramolecular network is formed by extensive H-bonding in complex ( 1 ). The supramolecular assembly in complex ( 1 ) is additionally consolidated via the existence of unusual cyclic hexameric water clusters. The antimicrobial activities for the present complexes have been examined against Escherichia coli (K-12), Bacillus subtilis (MTC-121), Staphylococcus aureus (IOASA-22), Salmonella typhymurium (MTCC-98), Candida albicans, Aspergillus fumigatus and Penicillium marneffei . The superoxide dismutase (SOD) activity of the Cu(II) complex ( 1 ) is also assessed employing nitrobluetetrazolium (NBT) assay. [ABSTRACT FROM AUTHOR] more...

The present contribution accounts for the synthesis and structural elucidation of a newly synthesised copper and zinc containing schiff base compounds obtained by the condensation of 1, 2-diphenylethane-1, 2-dione and dinitrophenyl hydrazine as main ligand and benzene-1,2-diamine as co-ligand respectively. The synthesised compounds were characterized by several techniques, including elemental analysis, molar conductance and electronic, FT-IR, XRD, mass and 1 H NMR spectral studies. The analytical and molar conductance values indicated that the complexes have square planar and tetrahedral geometry respectively. X-ray powder diffraction illustrates that they are crystalline in nature. The copper and zinc complexes were screened for their antimicrobial potential against some bacterial and fungi strains and the assay indicate that these complexes are good antimicrobial agents against these tested pathogens. [ABSTRACT FROM AUTHOR] more...

This article explores the syntheses of six mixed metal derivatives of antimony(III) and bismuth(III) by the reaction of ethane-1,2-dithiol and metal bis derivatives of dithiocarbamates and/or dithiophosphates ligands in 1:1:1 M stoichiometry. These derivatives have been characterized by physicochemical [elemental analysis (C, H, N, S, Sb and Bi), molecular weight and melting point determinations], spectral [UV–Visible, FTIR, NMR ( 1 H, 13 C and 31 P)], powder X–ray diffraction studies. These derivatives have nano-ranged crystallite size (8.18–18.04 nm) with monoclinic crystal system. All the synthesized derivatives have two metal centers (Sb and Bi) which elevate the zone of inhibition against four bacterial and two fungal species as compared to single metal species (metal precursors) as well as standard drugs. [ABSTRACT FROM AUTHOR] more...

• Chromonyl chalcone and pyrazoline were synthesized by greener approach. • The compounds were characterized by IR, NMR, and mass spectrometric techniques. • DFT and molecular docking studies have been reported. • Antibacterial and antifungal activities have been reported. The synthesis of biologically important chromonyl chalcone and pyrazoline derivative, via an impressive as well as an eco-friendly green approach, using LaCl 3 /nano SiO 2 catalyst under solvent-free heating method has been discussed here. In this methodology, chromonyl chalcone prepared from 3-formylchromone and 5-acetylthiobarbituric acid by Claisen Schmidt condensation reaction was further used as an intermediate for the synthesis of a novel bioactive pyrazoline derivative. The novel compounds structures were established by FTIR, NMR and mass spectroscopic techniques. Antimicrobial activities were assessed for compounds against a set of bacterial and fungal strains using disk diffusion method, which revealed compounds as good antibacterial and antifungal agents. Geometry optimizations of newly synthesized compounds have been performed on DFT level of theory by the B3LYP acting along with Gaussain 16, revision B.01 to calculate the geometric and electronic structure parameters. The molecular docking study was carried out using the structure of DNA bacterial gyrase with newly synthesized chromone-based pharmacophore scaffolds. [ABSTRACT FROM AUTHOR] more...

Four new nitrosubstituted acylthioureas i.e. 1-acetyl-3-(4-nitrophenyl)thiourea (TU1), 1-acetyl-3-(2-methyl-4-nitrophenyl)thiourea (TU2), 1-acetyl-3-(2-methoxy-4-nitrophenyl)thiourea (TU3) and 1-acetyl-3-(4-chloro-3-nitrophenyl)thiourea (TU4) have been synthesized and characterized (by C 13 and H 1 nuclear magnetic resonance, Fourier transform infrared spectroscopy and single crystal X-ray diffraction). As a preliminary investigation of the anti-cancer potencies of the said compounds, DNA interaction studies have been carried out using cyclic voltammetry and UV–vis spectroscopy along with verification from computational studies. The drug-DNA binding constants are found to be in the order, K TU3 9.04 × 10 6 M −1 > K TU4 8.57 × 10 6 M −1 > K TU2 6.05 × 10 6 M −1 > K TU1 1.16 × 10 6 M −1 . Furthermore, the antioxidant, cytotoxic, antibacterial and antifungal activities have been carried out against DPPH (1,1-diphenyl-2-dipicrylhydrazyl), Brine shrimp eggs, gram positive ( Micrococcus luteus , Staphylococcus aureus ) and gram negative ( Bordetella bronchiseptica , Salmonella typhimurium , Enterobacter aerogens ) and fungal cultures ( Aspergillus fumigatus , Mucor species, Aspergillus niger , Aspergillus flavus ) respectively. [ABSTRACT FROM AUTHOR] more...

• Schiff bases compounds were studied by FT-IR, 1H/13C-NMR and HRMS. • Structural, electronic and spectroscopic properties were predicted by DFT. • Very high first hyperpolarizability make them suitable NLO candidates. • Compounds (6 and 7) show a 20 mm maximum inhibition zone specifically against S. aureus ATCC 25923. This study reports a joint experimental, theoretical and microbiological investigation on the (E)-N,N- dimethyl-4-((pyridine-2-ylmethylene)amino)aniline (5) , (E)-N,N- dimethyl-4-((pyridine-4-ylmethylene)amino)aniline (6) and (E)-N,N -dimethyl-4-((pyridine-3-ylmethylene)amino)aniline (7). These compounds were synthesized with microwave method and their structures characterized by FT-IR, 1H-NMR, 13C-NMR, and elemental analysis tecniques. In the theoretical studies, torsional barriers analysis, ground state structure, Fourier Transform Infrared spectra (FT-IR), and Nuclear Magnetic Resonance spectra (NMR) of 5, 6, and, 7 were calculated by Density Functional Theory (DFT) computations. The conformers obtained from the torsional barrier scanning were optimized by B3LYP/6-31G(d,p) level. The harmonic vibrational frequencies, potential energy distribution (PED), infrared intensities, and NMR chemical shifts of the most stable conformers were determined using the B3LYP/6-311++G(d,p). Theoretically, predicted spectral data were compared with experimental results. Antimicrobial studies of the synthesized compounds were performed against various microbial strains. Antimicrobial activities of 5, 6, and , 7 were tested against selected bacteria and yeast through minimum inhibitory concentration (MIC) and diffusion method. Compound 7 was found to be the most active against bacteria and yeast, while compound 5 was found to be moderately active. Compounds 6 (against S. aureus and C. albicans) and, 7 were found to have a very high minimum inhibitory concentration, ranging between 1.95 and 7.81 g/mL (against P. aeruginosa and E. coli). Compounds (6 and 7) showed zone of inhibition values in the range of 10–20 mm against other bacteria except L. monocytogenes and S. thyphimurium. [Display omitted] [ABSTRACT FROM AUTHOR] more...

• Novel cyclohepta[ b ]thiophene incorporating pyrimidine, pyridine, and chromene moiety were designed and evaluated for their antimicrobial activities. • Time-kill kinetics, antibiofilm activity, and the DNA gyrase inhibition of the active thiophene compounds were evaluated. • Levofloxacin and Ciprofloxacin are used as the reference standards drugs. • The ɣ-radiation effect on the antimicrobial activity of most active synthesized thiophenes was analyzed. • In silico assessment of all the potent compounds pharmacokinetic and drug-likeness was performed. • The docking examination was carried out for the most promising derivatives inside the active site of DNA gyrase (4URO). The emergence of drug-resistant microbes is responsible for high morbidity and mortality worldwide. In our endeavors to cultivate novel and effectual antimicrobial agents, we present the triumphant synthesis of a novel class of cyclohepta-thieno-pyrimidins 4-8 , cyclohepta[ b ]thiophene appended 2-imino-2 H -chromene-3-carboxamide and 3-imino-3 H -benzo[ f ]chromene-2-carboxamide derivatives 9-11 molecules, to enrich their biological behavior. The desired molecules had undergone in-vitro appraisal for their antimicrobial activity, demonstrating encouraging results. Besides, the time-kill kinetics, antibiofilm activity and the DNA gyrase inhibition of the active thiophene compounds were evaluated. The DNA gyrase inhibition by the active thiophenes was also determined with IC 50 values to range between (5.3-18.7µM) compared with Levofloxacin and Ciprofloxacin. Also, the sum of the Fractional Inhibitory Concentration Index (ΣFICI) was used to assess synergy between thiophenes and Levofloxacin. Additionally, the antimicrobial activity of the most active thiophene derivative was analyzed after ɣ -irradiation. Moreover, the in-silico prediction methodology was contemplated for foretelling the physicochemical, pharmacokinetic and ADME traits of the most active synthesized compounds and the standard reference drugs: Levofloxacin and Ciprofloxacin. The docking examination was carried out for the most promising derivatives 1, 2, 3, 4, 9 , Novobiocin, and Levofloxacin inside the active site of DNA gyrase, and their respective docking scores were contrasted with the scores of the above-mentioned standard drugs. [Display omitted] [ABSTRACT FROM AUTHOR] more...

Abstract: Mixed ligand complexes were synthesised using nicotinamide as the primary ligand and nitrite as the secondary ligand were characterised by FT-IR, UV–Vis, 1H NMR, TG–DTA–DTG, X-ray powder diffraction and physical analytical studies. From the molar conductance, magnetic moment and electronic spectral data of the synthesised complexes a general formula of [M(ONO)2(NA)2] where M=Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and Hg(II) and [Cr2(ONO)6(NA)2] with a distorted octahedral structure were proposed. Thermal analyses show that the complexes lose molecules of hydration initially and subsequently expel anionic and organic ligands in continuous steps. The kinetic parameter values, such as, E *, ΔH *, ΔS * and ΔG * illustrate the spontaneous association of the metal and ligands in the formation of the complexes. The antimicrobial efficacy of the ligand and its complexes were examined by in vitro method against various pathogenic bacterial and fungal strains. The metal complexes were found to posses efficient antimicrobial properties compared to nicotinamide and a few of these complexes could turn out to be excellent models for the design of effective antibiotic drug substances. The intercalating interaction of Cu(II) complex with CT-DNA was inspected by absorption spectral and viscosity studies, thermal denaturation and electro-analytical experiments. [Copyright &y& Elsevier] more...

Abstract: The lanthanide complexes of [1,2-bis(benzimidazole-2-yl)ethane dihydrochloride], L1·2HCl and [1,4-bis(benzimidazole-2-onium)butane dihydrochloride], L2·2HCl having molecular formulae [Ln(L1)2Cl3H2O] and [Ln(L2)2Cl3H2O]·2H2O (Ln=La3+, Pr3+, Nd3+ and Gd3+), respectively, were prepared and characterized through IR, 1H and 13C NMR, ESI-mass, UV–visible and luminescence spectroscopic techniques. TGA data suggested presence of the coordinated and the lattice water. The oscillator strengths of the f–f transitions and the covalency parameters (β, b 1/2 and δ) have been evaluated from the electronic spectral data. The proposed octa coordinate geometry for the complexes has been ascertained from the molecular model computations. CV studies indicate formation of stable quasi-reversible redox couples PrIII/IV, Nd III/IV and GdIII/IV in solution. The in vitro antimicrobial activities of the complexes have been evaluated against gram +ve and gram −ve bacteria and fungi. [Copyright &y& Elsevier] more...

Abstract: The ternary complexes of stoichiometries [M(oda)(Bipy)H2O]·xH2O [M=Cu (1), x =4; Co (2), x =2; Ni (3), x =4 or Cr (4), x =3] and [VO(oda)(Bipy)]·2H2O (5), where H2oda=oxydiacetic acid and Bipy=2,2′-bipyridine, were prepared and characterized employing elemental, FAB-Mass, FT-IR, EPR, 1H and 13C NMR spectroscopic analyses. X-ray crystallography of (1) and (5) indicated a six coordinate distorted geometry. The antimicrobial activities of the complexes were investigated against Escherichia coli (k-12), Bacillus subtilis (MTC-121), Staphylococcus aureus (IOASA-22), Salmonella typhymurium (MTCC-98), Candida albicans, Aspergillus fumigatus and Penicillium marneffei. The superoxide dismutase (SOD) mimic activity of the Cu(II) complex (1) was assessed employing NBT assay. [Copyright &y& Elsevier] more...

Abstract: Metal complexes with the third-generation quinolone antibacterial agent sparfloxacin (SPFX) or 5-amino-1-cyclopropyl-7-(cis-3,5-dimethyl-1-piperazinyl)-6,8,di-fluoro-1-4-dihydro-4-oxo-3-quinocarboxylic acid have been synthesized and characterized with physicochemical and spectroscopic techniques such as TLC, IR, NMR and elemental analyses. In these complexes, sparfloxacin acts as bidentate deprotonated ligands bound to the metal through the pyridone oxygen and one carboxylate oxygen. The antimicrobial activity of these complexes has been evaluated against four Gram-positive and seven Gram-negative bacteria. Antifungal activity against five different fungi has been evaluated and compared with reference drug sparfloxacin. Fe2+–SPFX and Cd2+–SPFX complexes showed remarkable potency as compared to the parent drug. [Copyright &y& Elsevier] more...

Abstract: Novel cobalt-pyrazine-2,3-dicarboxylate complexes with 1,10-phenanthroline (phen), [Co(pzdca)(phen)2]2·11H2O (1), N,N,N′,N′-tetramethylethylenediamine (tmen), (H2tmen)[Co(pzdca)2(tmen)]·9H2O (2) and 2,2-dimethylpropane-1,3-diamine (dmpen), [Co(CO3)(dmpen)2](pzdca)0.5·H2O (3) have been synthesized and characterized by elemental and thermal analyses, spectroscopic (IR and UV–vis) and X-ray diffraction techniques. In 1 and 2, pyrazine-2,3-dicarboxylate ligand coordinated to the Co(II) ions through one nitrogen atoms of pyrazine ring and oxygen atoms of carboxylate group as a bidentate ligand and distorted octahedral geometries of 1 and 2 are completed by phen and tmen ligands, respectively. In 2, the tmen molecules exhibit chemically different functions; it coordinated to the Co(II) ion as a bidentate ligand and in the other form it protonated and acts as counter-ion. In complex 3, Co(III) ion is coordinated by four nitrogen atoms of dmpen and two oxygen atoms of CO3 ligand and the pzdca behaves as a counter-ion. Furthermore, structures of 1 and 2 contain extensive hydrogen bonding between crystal water molecules to form infinite 2D water layers and 1D water chains, respectively. In vitro antimicrobial activities of new complexes were tested against selected wild type and clinical microorganisms by MIC. Complexes exhibited antimicrobial activity at high concentrations against the bacteria, fungi and clinical isolate tested. [Copyright &y& Elsevier] more...

Abstract: Schiff base N-(2-hydroxy-3-methoxybenzalidene)1-aminonaphthalene has been synthesized from the reaction of 2-hydroxy-3-methoxybenzaldehyde with 1-aminonaphthalene. The compound were characterized by elemental analysis, FT-IR, 1H NMR, 13C NMR and UV–visible techniques. The UV–visible spectra of the Schiff base were studied in polar and nonpolar solvents in acidic and basic media. The structure of the compound has been examined cyrstallographically. There are two independent molecules in the asymmetric unit. It crystallizes in the monoclinic space group P21/c, with unit cell parameters: a=14, 602(2), b=5,800(1), c=16, 899(1)Å, V=1394.4(2)Å3, Dx=1.321gcm-3 and Z=4. The crystal structure was solved by direct methods and refined by full-matrix least squares to a find R=0.041 of for 1179 observed reflections. The title compound''s antimicrobial activities also have been studied. The antimicrobial activities of the ligand has been screened in vitro against the organisms Escherichia coli ATCC 11230, Staphylococcus aureus ATCC 6538, Klebsiella pneumoniae UC57, Micrococcus luteus La 2971, Proteus vulgaris ATCC 8427, Pseudomonas aeruginosa ATCC 27853, Mycobacterium smegmatis CCM 2067, Bacillus cereus ATCC 7064 and Listeria monocytogenes ATCC 15313, the yeast cultures Candida albicans ATCC 10231, Kluyveromyces fragilis NRRL 2415, Rhodotorula rubra DSM 70403, Debaryomyces hansenii DSM 70238 and Hanseniaspora guilliermondii DSM 3432. [Copyright &y& Elsevier] more...

A series of nineteen thiazole Schiff base derivatives 2a-2s were synthesized (Scheme 1) and elucidated by spectral analyses (IR, 1H NMR and HRMS). The evaluation of their antimicrobial activities against two gram-positive, two gram-negative, and two fungal strains revealed that some compounds displayed moderate antimicrobial activities compared to standard ciprofloxacin and miconazole in disc diffusion technique. Compound 2a displayed very strong antioxidant efficacy (IC 50 = 3.52 ± 0.86 µg/mL) compared to standard ascorbic acid (IC 50 = 27.34 ± 1.86 µg/mL) in DPPH free radical scavenging assay. Compounds 2j, 2k , and 2m displayed significant antioxidant activities in this assay as well. In silico analysis predicted that the synthesized compounds follow the Lipinski's rule of five and Veber's rule with one exception. The compounds displayed good drug-likeness and drug-score properties. The molecular docking studies predicted that the synthesized thiazole Schiff base derivatives are tolerable in putative receptor binding sites. [Display omitted] [ABSTRACT FROM AUTHOR] more...

• N -pendant derivative L CX of isomeric macrocyclic ligand L CX has been prepared. • Nickel(II), copper(II), and cobalt(III) complexes of L CX have been synthesized. • Axial substitution reactions on a trans -cobalt(III) complex were performed. • Characterization of the new compounds was carried out. • Antimicrobial investigations of the new compounds were executed. Condensation of 1,2-diamino propane with acetone in the presence of perchloric acid furnished a 14-membered octamethyl tetraazamacrocycle, Me 8 [14]diene⋅2HClO 4 , which further produced a mixture of isomeric ligands, Me 8 [14]anes (L A , L B , and L C), on reduction with NaBH 4 and subsequent extraction with CHCl 3 (pH > 12). The isomers were separated by fractional crystallization from xylene. Interaction of L C with excess acrylonitrile afforded an N -pendant derivative, L CX, in which two cyanoethyl groups were attached to less crowded nitrogen atoms (N 4 and N 11). Upon the interaction of L CX with Ni(CH 3 COO) 2 ⋅4H 2 O, Cu(ClO 4)₂⋅6H 2 O, and Co(CH 3 COO)₂⋅4H₂O, square planar [Ni(L CX)](ClO 4) 2 and [Cu(L CX)](ClO 4) 2 and octahedral trans -[Co(L CX)Cl 2 ](ClO 4), respectively, were produced. Axial substitution reactions of trans -[Co(L CX)Cl 2 ](ClO 4) with KCNS, KM (M = NO 3 , Br, or I), and NaNO 2 afforded substituted trans -[Co(L CX)(NCS) 2 ](SCN), trans -[CoL CX (X) 2 ](ClO 4), and trans -[Co(L CX)(NO 2) 2 ](ClO 4), respectively. The ligand and corresponding metal complexes were characterized based on the analytical, spectroscopic, magnetic moment, and molar conductivity data. Gram-positive and gram-negative bacteria and different fungi were used to evaluate the antibacterial and antifungal activities of the ligand and its metal complexes. [ABSTRACT FROM AUTHOR] more...

• Synthesis and characterization of novel chelates of benzimidazole ligand. • Studying the metallochromic behavior of the free ligand. • Studying the binding of the ligand and its chelates with CT-DNA. • Investigation the antimicrobial activities of the chelates. Three novel chelates, [Ru (L) 3 2H 2 O, C1, [Ni L (H 2 O) 3 (AcO)]H 2 O, C2, and [Cu L (H 2 O)(AcO)], C3, derived from 2-(2-hydroxy phenyl)-1-H –benzimidazole) H L , have been designed. The structures of the isolated compounds have been elucidated by elemental analysis, molar conductance, thermal analysis, spectral data (UV–Vis, mass spectra, IR, fluorescence), thermal analysis (TGA) and magnetic moment measurements. The IR spectral data ascertained that the HL compound acts as a monobasic bidentate ligand via the O and N atoms of the OH and C=N groups of the benzimidazole moiety, respectively. The spectral and magnetic measurements implied octahedral structures for C1 and C2 and square planar geometry for C3. The kinetic and thermodynamic parameters of the thermal decomposition stages have been evaluated. Molecular orbital calculations have been performed. The metallochromic behavior of the investigated free ligand was studied in the presence of Ru(III), Ni(II) and Cu(II) ions. The observed spectral changes indicated the ability of HL to act as potential optical sensor for probing these metal ions. Interaction of the investigated compounds with CT-DNA was studied via electronic absorption and emission spectroscopy, as well as ethidium bromide displacement. The results suggested that all compounds interact through intercalative mode. The binding behavior and binding constants have been evaluated and discussed. The CT-DNA-binding constants confirmed the strong intercalation between the investigated ligand and metal complexes with the CT-DNA, suggesting that the investigated compounds can be used as promising therapeutic drug. Finally, the antimicrobial activities of the metal complexes have been screened. Image, graphical abstract [ABSTRACT FROM AUTHOR] more...

• Three triphenyltin(IV) compounds 1–3 were synthesized and characterized. • 1 showed intermediate between distorted TBP and square-pyramidal geometry. • 3 exhibited distorted tetrahedral geometry with monomeric structure. • Hirshfield surfaces analysis of 1 and 3 observed different stacking interactions. • Compounds showed significant antimicrobial activity. Synthesis of three new triphenyltin(IV) compounds 1 – 3 were reported by the reaction of azo-carboxylic acid ligands viz.2/4-(2-hydroxynaphthylazo)-benzoic acids [compounds 1 and 2 or 2-(4-hydroxynaphthylazo)-benzoic acid [compound 3] with triphenyltin(IV) hydroxide. The compounds were completely characterized with the help of elemental analysis, IR and multinuclear 1H, 13C and 119Sn]-NMR spectroscopy. The mode of coordination and geometry around tin atoms in compounds 1 and 3 were determined by X-ray crystallography. Compounds 1 and 3 exhibited monomeric structure with intermediate deformation between the trigonal bipyramidal and square-pyramidal geometry or distorted tetrahedral geometry around tin atom respectively. Hirshfeld surface analysis for both structures was also performed. The main difference between 1 and 3 is observed for stacking interactions. 119Sn NMR spectral study of all the compounds suggested that the compounds adopted 4-coordinated tetrahedral structures in solution. The antimicrobial activities of the compounds showed effective antibacterial activity against S. aureus and antifungal activity against F. oxysporum. The antimicrobial activity of these compounds was found to be higher than the tested standard compounds against some selected microbes. Image, graphical abstract [ABSTRACT FROM AUTHOR] more...

Alstonia boonei is a medicinal plant use for the treatment of infections. In this study, two new compounds were purified from Alstonia boonei stem bark using standard methods and their effects on mitochondrial permeability transition and antimicrobial properties in vitro and in silico were studied. Mitochondrial Permeability Transition (mPT) pore opening and antibacterial activity of these compounds were assessed. Furthermore, the structures of these compounds were docked against caspase 3, caspase 9, Bcl2-Associated X protein (Bax), Bcl-2-antagonist/killer 1 (Bak), cytochrome c , p53, B cell lymphoma 2 (Bcl-2) and bacterial Peptidoglycan Glycosyltransferases (PGT). The two new compounds isolated were: tetrahydro-4-(7-hydroxy-10-methoxy-6, 14-dimethyl-15-m-tolylpentadec-13-enyl) pyran-2-one (1) and isobutyryl acetate (2) Compound 1 which opened the mPT pore (in vitro) at the highest concentration (80 μg/mL), had significant antimicrobial effects against P. aeruginosa ATCC 19582 and Sal. Typhi while 2 had significant effects against St aureus OK2b and K. pneumoniae ATCC4352. Compound 1 preferentially bound to Bcl-2 of all the apoptotic proteins tested and it also exhibited a higher binding affinity to PGT than compound 2. The two compounds have low toxicity. These results suggested that compound 1 can cause mitochondrial dysfunction via mitochondrial-mediated apoptosis and it could also serve as an antimicrobial agent via the disruption of the bacterial glycan core. Image 1 • Two new compounds were purified from A. boonei. • These compounds have permeability potentials in mitochondrial membrane. • They have antibacterial properties in vitro and in silico. • They have good pharmacokinetic properties. [ABSTRACT FROM AUTHOR] more...

3,5-bis(2,5-dimethylphenyl)pyridine (1); a novel derivative of 3,5-dibromopyridine was synthesized via Pd(0) catalyzed cross coupling reaction. The compound under investigation was characterized by XRD and different spectroscopic techniques. Density functional theory (DFT) was applied to compound 1 and experimental XRD data and DFT data are found in good agreement with each other. Calculated FT-IR results are found to be in excellent agreement with experimental FT-IR findings. Chemical shift values for NMR were calculated for compound (1) in the gas phase which show deviation to experimental values might be because of medium affects. Natural bond orbital (NBO) study was also performed which indicates that the methyl groups influence van der Waals interactions among the adjacent bonds, especially, delocalization of energy during the interaction. Energy gap values of HOMO-LUMO calculated through frontier molecular orbital (FMO) analysis provided enough evidence that molecule is biologically active. Molecular electrostatic potential (MEP) mapping indicated that electron density is located on nitrogen whereas carbon and hydrogen atom are favorable sites for nucleophilic attack. Moreover, the bioactivities of compound (1) have been confirmed by the experimental activity in terms of zones of inhibition against bacteria and fungus. Image 1 • A novel derivative of 3,5-dibrommopyridine was synthesized via Pd(0) catalyzed cross coupling reaction. • 3,5-bis(2,5-dimethylphenyl)pyridine (1) compound was characterized by XRD and NMR, FT-IR spectroscopic techniques. • DFT calculations were performed for various molecular properties such as NBO, FMO analysis and MEP mapping etc. • Calculated FT-IR results were found to be in excellent agreement with experimental FT-IR findings. • Bioactivities of 3,5-bis(2,5-dimethylphenyl)pyridine (1) were confirmed experimentally and theoretically. [ABSTRACT FROM AUTHOR] more...