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A quick and solvent-free mechanochemical method was employed for the post-synthetic modification of a Ni-MOF. The Ni-MOF was utilized as an electrocatalyst for oxygen evolution and reduction, and biomass conversion applications.

GaOOH powders of submicron dimensions were synthesized through a simple, surfactant-free hydrothermal synthesis at pH values of 7 and 14. Sn and Cr at concentrations of 2 mol% and 1 mol%, respectively, were successfully incorporated into a GaOOH lattice at pH = 7. The synthesized powders were characterized through XRD, SEM, UV-Vis spectroscopy, XPS, and PL spectroscopy to untangle their structural, morphological, optical, elemental, and compositional- and defect-level analyses, respectively. All samples were individually tested for their in vitro anti-proliferation activities against three human cancer cell line profiles, namely, lung carcinoma (A549), colon adenocarcinoma (LoVo), and hepatocellular carcinoma (HuH-7). The samples showed obtrusive anti-proliferation activity against the three cancer line profiles. An apoptotic cell killing mechanism was found in the studied samples after a successful analysis of various staining assays and flowcytometric analyses in the A549 cancer cell profile. Cr loading at 1 mol% enhanced the cancer cell inhibition property of GaOOH against all cancer cells investigated. Also, the morphology and doping levels were observed to have a collective effect on the anti-proliferation activity of GaOOH with specificity in treating certain cancer cells.

The sensitivity of protein molecular structures makes them susceptible to aggregation in conditions unfavorable for the maintenance of their native folds. The aggregation of proteins leads to many disorders, but the inhibition of amyloid fibril formation using metal-containing small molecules is gaining popularity. Herein we report the effect of nickel(II) complexes (N1, N2, N3, and N4) bearing thiosemicarbazones on the inhibition of amyloid fibril formation by insulin. The interactions of the complexes with amyloid fibrils were investigated using various biophysical techniques, including light scattering, intrinsic fluorescence assay, thioflavin T (ThT) assay, and Fourier transform-infrared spectroscopy. The results revealed that the phenyl-substituted N3 was an efficient inhibitor of amyloid fibril formation and maintained the insulin in its native structure despite conditions promoting fibrillation. Nickel(II) complexes containing indole based thiosemicarbazones were efficient in inhibiting the amyloid fibril formation and maintaining the insulin in its native structure in unfavorable conditions.

Fourteen new RuII -arene (p-cymene/benzene) complexes (C1-C14) have been synthesized by varying the N-terminal substituent in the furoylthiourea ligand and satisfactorily characterized by using analytical and spectroscopic techniques. Electrostatic potential maps predicted that the electronic effect of the substituents was mostly localized, with some influence seen on the labile chloride ligands. The structure-activity relationships of the Ru-p-cymene and Ru-benzene complexes showed opposite trends. All the complexes were found to be highly toxic towards IMR-32 cancer cells, with C5 (Ru-p-cymene complex containing C6 H2 (CH3 )3 as N-terminal substituent) and C13 (Ru-benzene complex containing C6 H4 (CF3 ) as N-terminal substituent) showing the highest activity among each set of complexes, and hence they were chosen for further study. These complexes showed different behavior in aqueous solutions, and were also found to catalytically oxidize glutathione. They also promoted cell death by apoptosis and cell cycle arrest. Furthermore, the complexes showed good binding ability with the receptors Pim-1 kinase and vascular endothelial growth factor receptor 2, commonly overexpressed in cancer cells.

Six different acylthiourea ligands (L1–L6) and their corresponding Ru(II)-p-cymene complexes (P1–P6) were designed to explore the structure–activity relationship of the complexes upon aliphatic chain and aromatic conjugation on the C- and N-terminals, respectively. The compounds were synthesized and adequately characterized using various analytical and spectroscopic techniques. The structures of P2–P6, solved using single crystal X-ray diffraction (XRD), confirmed the neutral monodentate coordination of the S atoms of the acylthiourea ligands to Ru(II) ions. In silico studies showed an increase of lipophilicity for the ligands with an increase in alkyl chain length or aromatic conjugation at the C- or N-terminal, respectively. Subsequently, mitogen-activated protein kinases (MAPK) were predicted as one of the primary targets for the complexes, which showed good binding affinity towards extracellular signal-regulated kinases (ERK1, ERK2 and ERK5), c-Jun N-terminal kinase (JNK) and p38 of the MAPK pathway. Henceforth, the complexes were tested for their anticancer activity in lung carcinoma (A549) and cisplatin-resistant lung carcinoma (cisA549R) cells and human umbilical vein epithelial normal cells (HUVEC). Interestingly, an increase in chain length or aromatic conjugation led to an increase in the activity of the complexes, with P5 (7.73 and 13.04 μM) and P6 (6.52 and 14.45 μM) showing the highest activity in A549 and cisA549R cells, which is better than the positive control, cisplatin (8.72 and 44.28 μM). Remarkably, we report the highest activity yet observed for complexes of the type [(η6-p-cymene)RuIICl2(S-acylthiourea)] in the tested cell lines. Aqueous solution studies showed that complexes P5 and P6 are rapidly hydrolyzed to produce solely aquated species that remained stable for 24 h. Staining assays and flow cytometric analyses of P5 and P6 in A549 cells revealed that the complexes induced apoptosis and arrested the cell cycle predominantly in the S phase. In vivo studies demonstrated the higher toxicity of cisplatin and a comparatively higher survival rate of mice injected with the most active complex P6. Histological analyses revealed that treatment with P6 at high doses of up to 8 mg kg−1 did not cause any palpable damage to the tested organs.

Metal complexes have numerous applications in the current era, particularly in the field of pharmaceutical chemistry and catalysis. A novel synthetic approach for the same is always a beneficial addition to the literature. Henceforth, for the first time, we report the formation of three new Pd(II) complexes through the Michael addition pathway. Three chromone-based thiosemicarbazone ligands (SVSL1–SVSL3) and Pd(II) complexes (1–3) were synthesized and characterized by analytical and spectroscopic tools. The Michael addition pathway for the formation of complexes was confirmed by spectroscopic studies. Distorted square planar structure of complex 2 was confirmed by single-crystal X-ray diffraction. Complexes 1–3 were subjected to DNA- and BSA-binding studies. The complex with cyclohexyl substituent on the terminal N of thiosemicarbazone (3) showed the highest binding efficacy toward these biomolecules, which was further understood through molecular docking studies. The anticancer potential of these complexes was studied preliminarily by using MTT assay in cancer and normal cell lines along with the benchmark drugs (cisplatin, carboplatin, and gemcitabine). It was found that complex 3 was highly toxic toward MDA-MB-231 and AsPC-1 cancer cells with IC50 values of 0.5 and 0.9 μM, respectively, and was more efficient than the standard drugs. The programmed cell death mechanism of the complexes in MDA-MB-231 cancer cells was confirmed. Furthermore, the complexes induced apoptosis via ROS-mediated mitochondrial signaling pathway. Conveniently, all the complexes showed less toxicity (≥50 μM) against MCF-10a normal cell line. Molecular docking studies were performed with VEGFR2, EGFR, and SARS-CoV-2 main protease to illustrate the binding efficiency of the complexes with these receptors. To our surprise, binding potential of the complexes with SARS-CoV-2 main protease was higher than that with chloroquine and hydroxychloroquine., The Pd(II) complexes were synthesized through Michael addition and characterized. The complexes exhibited good binding with biomolecules, including SARS-CoV-2 main protease, and potential antiproliferative activity through ROS-mediated mitochondrial apoptosis pathway.

Iron is one of the cheapest and abundant metals on the earth’s crust. Both its oxides and metallic form are highly active as oxidation and reduction catalysts. Its oxide forms such as Fe2O3 and Fe3...

The Pd nanoparticles generated in situ from Pd–pincer complexes catalyzed Heck coupling reaction. For this purpose, new Pd(II)–ONO pincer complexes (1–4) containing acylthiourea ancillary ligand were obtained by treating [Pd(ONO)(CH3CN)] with the respective N-substituted carbamothioyl benzamide ligand (L1–L4). Formation of these complexes was confirmed by UV–Visible, FT-IR, NMR and mass spectroscopic techniques. The sizes of in situ formed Pd nanoparticles were greatly affected by the substituent in ancillary ligand, which in turn influenced their catalytic activity towards Heck coupling reaction. The in situ formed Pd nanoparticles during Heck reaction were removed from the reaction medium and analyzed using HR-TEM to estimate the sizes of the Pd nanoparticles. Complex [Pd(ONO)((N-benzylcarbamothioyl)benzamide)] (1) which does not possess any substituent on the benzyl moiety of acylthiourea produced the smallest Pd nanoparticles with the average particle size of 3.7 nm. Hence, complex 1 showed the utmost catalytic activity. With complex 1, 51–99% of conversion was observed during Heck coupling reaction of styrene with various aryl halides. XPS results confirmed that the recovered black particles were Pd(0). A reasonable recyclability results were achieved by these in situ generated Pd nanoparticles.

Two Schiff bases derived from aminobenzothiazole derivatives with Salicylaldehyde/Bromosalicylaldehyde namely 2-[6-Methylbenzothiazol-2-ylimino) methyl phenol (1) and 3-Bromo-2-[6-methylbenzothiazo...

MIL-88B is a class of metal–organic framework (MOF) that has been widely explored in catalysis. Iron- and chromium-based MIL-88B MOFs were prepared and characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and N2 adsorption/desorption measurements. The MIL-88B MOFs were investigated as catalysts for transfer hydrogenation (TH) of carbonyl compounds (ketones and aldehydes) and biomass derivatives (levulinic acid and furfural) with 2-propanol as a hydrogen donor. Their conversion and selectivity were excellent. The recovered catalyst was reused ten times, with no significant loss in catalytic activity. The recovered catalyst after the tenth run retained its original crystallinity and morphology, which were confirmed by SEM and powder XRD studies. Catalyst reusability for levulinic acid (LA) conversion was also studied. The activation energy for the transformation of LA to γ-valerolactone (GVL) was 25.44 kJ mol−1. The catalytic performance of MIL-88B(Fe) was compared with that of MIL-53(Fe).

A simple and efficient direct radical C-2 arylation of 3-aminochromone derivatives with aryl hydrazine is described. The aryl hydrazine acts as an initiator and source for the aryl radical via the cleavage of the C-N bond of aryl hydrazine. The reaction proceeds via a base-promoted single electron transfer (SET) pathway. The aryl radical abstracts a single electron from 3-aminochromone, which generates a C2-radical iminium ion to undergo a cross-coupling reaction with an aryl radical, and this process offers an array of regioselective 2-aryl substituted 3-aminochromones.

The reaction between zinc(II) acetate dihydrate and ((1H-indol-3-yl)methylene)-N-methyl­hydrazinecarbothioamide (L) in methanol results in the formation of Zn(II) complex [Zn(C11H11N4S)2] (1). The complex is characterized by CHNS and various spectroscopic analyses. The structure of the complex is determined by the single crystal X-ray diffraction technique. XRD reveals that the Zn(II) complex crystalizes in the triclinic system with the P-1 space group and has a distorted tetrahedral geometry. Two ligand molecules are coordinated to the Zn(II) ion in the bidenatate monobasic (NS–) fashion.

Acylthiourea-based Pd(II) complexes (1-5) with a PPh

Six different acylthiourea ligands (L1-L6) and their corresponding Ru(II)

The direct synthesis of SnTUD-1 with different Si:Sn ratios (100, 50 and 25) by using non-surfactant template triethanolamine (TEA). It functioned as a structure-directing agent and assisted to graft the Sn ions into the TUD-1 silica layer. The physicochemical properties of these materials were examined with XRD, N2 sorption, DR UV–Vis, NH3-TPD, 29Si-NMR, HRTEM, XPS and pyridine adsorbed FT-IR studies, which indicated highly interconnected mesoporous structure with wormhole like morphology. Sn4+ ions were mainly tetrahedrically coordinated with silica; while increase of loading lead to the formation of nanocrystalline SnO2 with different sizes. Materials showed acidity in the range of 0.13–0.31 mmol/g. Synthesized catalysts were tested in the esterification of levulinic acid (LA) with various aliphatic alcohols and exhibited excellent activity. The catalyst was recycled five times without loss of its activity.

Four Zn(II) complexes (1–4) featuring indole thiosemicarbazones were synthesized and well-characterized by elemental analyses and various spectroscopic (UV–Vis, FT-IR, 1H NMR, 13C NMR and mass) techniques. The single crystal X-ray crystallographic study revealed a tetrahedral geometry for complexes 1 and 3. The interactions of the Zn(II) complexes 1–4 with calf thymus DNA (CT DNA) were examined by UV–Vis spectroscopy and viscosity measurements, which implied that the complexes bound to CT DNA via intercalation, and complex 4 showed a higher binding affinity than the other complexes. The protein binding interaction of the complexes was monitored by fluorescence and absorption techniques, which showed that the complexes could bind effectively with bovine serum albumin (BSA) and the type of quenching mechanism was found to be static. Synchronous fluorescence experiments showed the changes in the conformations of the protein micro regions. Molecular docking studies were performed in order to get a better picture of the binding of the complexes with the molecular targets DNA hexamer and BSA. The in vitro cytotoxicity of the complexes against two human cancer (A549 and MCF7) cell lines, two human non-tumorigenic (MCF-10A and HEK-293) cell lines and one non-cancerous mouse fibroblasts (L929) cell line was evaluated using an MTT assay. Complex 4, which has an N-terminal cyclohexyl group, showed moderate activity [IC50 = 37.9 (A549) and 60.3 μM (MCF7)] that was comparable with the familiar anticancer drug cisplatin. Also, fortunately, the activity of complex 4 was found to be specific to cancer cells. The apoptosis cell death mechanism for complex 4 was assessed by the Hoechst staining method.

Acylthiourea derivatives, 1-benzoyl-3-(quinolin-8-yl)thiourea (1), 1-(furan-2-carbonyl)-3-(quinolin-8-yl)thiourea (2) and 1-(thiophene-2-carbonyl)-3-(quinolin-8-yl)thiourea (3) were synthesized and well characterized by using NMR (1H and 13C), FT-IR, UV–visible and mass spectroscopy tools. The molecular structures of compounds 1 and 3 were confirmed by single crystal X-ray crystallography. The fluorescence emission of the compounds (1–3) was studied using fluorescence spectrophotometer. The sensing ability of the acylthiourea derivatives was analyzed by colorimetric, UV–visible and fluorescence titrations. In silico anti-inflammatory, antimalarial and anti-tuberculosis activities were investigated using molecular docking studies. Acylthiourea derivatives also possessed good antioxidant activity.

Organometallic Ru(II)-arene complexes have emerged as potential alternatives to platinum appended agents due to their wide range of interesting features such as stability in solution and solid, significant activity, less toxicity and hydrophobic property of arene moiety, etc. Hence, a series of Ru(II)-p-cymene complexes, [(η6-p-cymene)Ru(η2-N,N-L1)Cl]Cl (1), [(η6-p-cymene)Ru(η1-N-L2)Cl2] (2) and [(η6-p-cymene)Ru(η1-N-L3)Cl2] (3) were prepared from pyrazole based ligands [2-(1H-pyrazol-3-yl)pyridine (L1), 3-(furan-2-yl)-1H-pyrazole (L2) and 3-(thiophen-2-yl)-1H-pyrazole (L3)], and [RuCl2-(η6-p-cymene)] dimer. The new Ru(II)-p-cymene complexes were well characterized by elemental analysis, and spectroscopic (FT-IR, UV-Visible, 1H NMR, 13C NMR and mass) and crystallographic methods. The Ru(II)-p-cymene complexes (1-3) were found to adopt their characteristic piano stool geometry around Ru(II) ion. The calf thymus DNA (CT-DNA) binding ability of the new complexes was investigated by electronic absorption spectroscopic titration and viscosity methods. The molecular docking study results showed that complex 1 strongly bound with targeted biomolecules than 2 and 3. Docked poses of bidentate pyrazole based Ru(II)-p-cymene complex 1 revealed that the complex formed a crucial guanine N7 position hydrogen bond with DNA receptor. Complexes 1-3 might hydrolyze under physiological conditions and form aqua complexes 4-8, and docking calculations showed that the aqua complexes bound strongly with the receptors than original complexes. The in vitro cytotoxicity of the Ru(II)-p-cymene complexes and cisplatin was evaluated against triple negative breast cancer (TNBC) MDA-MB-231 cells. Our results showed that the inhibitory effect of bidentate pyrazole based Ru(II)-p-cymene complex 1 on the growth of breast cancer cells was superior to other tested complexes.

Eight new organometallic Ru(II)–arene complexes of the type [RuCl2(η6-arene)(η1-S-aroylthiourea)] (arene = p-cymene or benzene) were synthesized in order to evaluate the effect of the arene moiety and the substituent of the aroylthiourea ligand on the cytotoxicity of the complexes. The ligands (L1 and L2) and complexes (1–8) were characterized using analytical and spectroscopic (UV–visible, infrared, 1H NMR, 13C NMR, and mass) methods. The structure of the ligands (L1 and L2) and complexes (1 and 3–6) was obtained from single-crystal X-ray diffraction studies. The cytotoxicity of the complexes was evaluated against four different cancer cell lines: MCF-7 (breast), COLO 205 (colon), A549 (lung), and IMR-32 (neuroblastoma). All the complexes showed good cytotoxicity and the highest was in the IMR-32 cell line, which articulates the specificity of these complexes toward the IMR-32 cancer cell line. The complexes 5, 7, and 8 exhibited remarkable cytotoxicity in the entire cancer cell lines tested, which was comparable with the standard drug, cisplatin. The anticancer mechanism of the complexes 3 and 7 in IMR-32 cells was evaluated by bright-field microscopy, intracellular reactive oxygen species (ROS), mitochondrial membrane potential (MMP), DNA damage, and caspase-3 analyses. The cells treated with the complexes showed upregulated caspase-3 compared to the control, and it was found that ROS and MMP were dose-dependent on analysis. Also, bright-field microscopy and 4′,6-diamidino-2-phenylindole (DAPI) staining have correspondingly shown cellular membrane blebbing and DNA damage, which were morphological hallmarks of apoptosis. The study concluded that the complexes promoted the oxidative stress-mediated apoptotic death of the cancer cells through the generation of intracellular ROS, depletion of MMP, and damage of the nuclear material.

Ruthenium complexes are fascinating for exploration as anticancer drugs after the entry of KP1019 and NAMI-A in phase II clinical trials for the treatment of metastatic tumors. The reaction of guanidine ligands with [RuCl(μ-Cl)(η6-p-cymene)]2 yielded monometallic Ru(II) complexes with N,N-type (1) and O,N-type (2 and 3) ligands, whereas both monometallic (O,N) (7) and bimetallic Ru(II) (4–6) complexes were obtained when [RuCl(μ-Cl)(η6-benzene)]2 was used as a precursor. The complexes were characterized using analytical, spectroscopic (UV–vis, FT-IR, NMR, and mass), and single-crystal X-ray crystallography techniques. The stability of the complexes was tested by UV–visible spectroscopy. The complexes were investigated for their interaction with calf thymus (CT) DNA and bovine serum albumin using various spectroscopic techniques. Spectroscopic and viscosity experiments revealed that the intrinsic DNA binding affinity of the Ru–p-cymene complexes was greater than that of the analogous Ru–benzene complexes du...

An efficient synthesis of 3-aminochromones and 3-alkylchromones by a N-heterocyclic carbene (NHC) catalyzed intramolecular hydroacylation reaction of corresponding salicylaldehyde derived nitriles and activated alkynes respectively in ionic liquids under microwave conditions is reported. This protocol has the advantages of environmental friendliness, higher yields, shorter reaction times, and convenient operation using the commercially available thiazolium catalyst. The origin of the chemical reactivity of the NHC-catalyzed intramolecular hydroacylation reaction of nitriles is studied using Density Functional Theory (DFT). The results suggest that 3-aminochromone formation occurs via an acyl anion intermediate called a Breslow intermediate (INT2) through TS2. The Breslow intermediate (INT2) forms a carbon–carbon bond with the nitrile carbon to produce an imine intermediate INT3viaTS3, which further undergoes imine to amine tautomerism to give the end product. Some of the derivatives of 3-aminochromone are subjected to amine functionalization in one pot to obtain a library of compounds for anticancer activity. Among the investigated compounds, 2c (SVM-2), 4c (SVM-4) and 2d (SVM-9) show IC50 values of 5.18, 4.89 and 27.3 μM respectively in HeLa S3 cancer cells. Compound 5c (SVM-5) shows IC50 values of 13.3 and 14.2 μM in A549 and HeLa S3 cancer cells, respectively. Compounds 2c (SVM-2) and 4c (SVM-4) produce morphological changes and control the colony formation in HeLa S3 cells, which indicates that these small molecules are potential candidates for anticancer drugs.

The reaction of copper(I) bromide with aroylthiourea ligands (L) in the molar ratio 1 : 3 resulted in the formation of [CuBr(L)3]. The complexes were well characterized by analytical and spectroscopic (UV-visible, FT-IR, NMR and mass) techniques. Tetrahedral geometry of complexes 1 and 3 was confirmed by single crystal X-ray diffraction study. The interaction of complexes with biomolecules (DNA/protein) has been evaluated using spectrophotometric and spectrofluorometric techniques. The compounds were screened for their in vitro cytotoxicity against cancer and normal cell lines. Complexes 1 and 2 showed potent cytotoxic activity against HeLa cells with an IC50 value of 1.23 and 0.47 μM, respectively. Staining and colony formation studies were also carried out for the most active complexes to predict the morphological changes and colony formation ability, respectively.

Sodium ion capacitors are under extensive investigation as companionable pre-existing lithium ion batteries and sodium ion batteries. Finding a suitable host for sodium ion storage is still a major challenge. In this context, here we report a MoS2 nanoflowers@rGO composite produced via a hydrothermal method followed by an ultra sonication process as a sodium ion symmetric hybrid supercapacitor. The structural and electrochemical performances of the electrode material were investigated to establish its applicability in sodium ion capacitors. The electrochemical performance was evaluated using metallic sodium in a half cell configuration which delivered a maximum specific capacitance of 226 F g−1 at 0.03 A g−1. When examined as a symmetric hybrid electrode (full cell) it delivered a maximum capacitance of 55 F g−1 at 0.03 A g−1. This combination may be a new gateway for upcoming research work which deals with sodium ion storage applications. The results confirmed that the as-synthesized MoS2 nanoflowers@rGO heterostructure electrode exhibited notable electrochemical behaviour.

Fourier transform infrared (FT-IR) and Raman (FT-Raman) spectra of the nickel(II) complex of 2-aminonicotinaldehyde (Ni(II)CANA) have been recorded and analyzed. The experimental work has been complemented by density functional theory (DFT) computations. The most optimized structure of the titled compound and their minimum energies were analyzed by using B3LYP functional with 6-31G(d,p) basis set. The calculated wave numbers from density functional theory method was scaled down to coincide with the experimentally recorded values and results were reported. The RMS error between the scaled calculated and observed fundamentals is 5.42 cm−1. All the vibrational modes of the compound under studied were ascribed and the structural properties predicted and analyzed. The first hyperpolarizability (β), polarizability (α) and dipole moment (μ) of the compound was computed and the results were reported. The thermo dynamical parameters and HOMO-LUMO energy gap were calculated. To obtain the electronic transitions from UV–Visible spectra have been calculated using the TD-DFT method. NBO analysis was executed to know the transfer of electrons within the molecule, MESP analysis also performed for (Ni(II)CANA). The in vivo anti-inflammatory activity was done by using the carrageenan-induced rat paw edema method in Albino rats (Wister strain). The results revealed that it possesses a significant anti-inflammatory activity. The docking studies were carried out to identify the potential COX-2 inhibitor. In order to understand the binding mode of the titled compound to the cell line, molecular docking studies were also carried out and it was found to have a binding energy of −8.67 kcal/mol.