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Reports on the recycling of used flexible shampoo, detergent or lotion bottle as wash bottle for chemistry laboratories.

Glioma is the most aggressive and dangerous primary brain tumor with a survival time of less than 14 months. Segmentation of tumors is a necessary task in the image processing of the gliomas and is important for its timely diagnosis and starting a treatment. Using 3D U-net architecture to perform semantic segmentation on brain tumor dataset is at the core of deep learning. In this paper, we present a unique cloud-based 3D U-Net method to perform brain tumor segmentation using BRATS dataset. The system was effectively trained by using Adam optimization solver by utilizing multiple hyper parameters. We got an average dice score of 95% which makes our method the first cloud-based method to achieve maximum accuracy. The dice score is calculated by using Sørensen-Dice similarity coefficient. We also performed an extensive literature review of the brain tumor segmentation methods implemented in the last five years to get a state-of-the-art picture of well-known methodologies with a higher dice score. In comparison to the already implemented architectures, our method ranks on top in terms of accuracy in using a cloud-based 3D U-Net framework for glioma segmentation. [ABSTRACT FROM AUTHOR]

An easy and simple approach is developed to fabricate nano‐composite packaging films from starch molecules reinforced with cellulose nanofibers derived from unripe from banana peel. Addition of 10g (w/w, dry starch basis) of cellulose nanofibers into the starch matrix results in improved mechanical and thermal stability of the nano‐composite films. The results show that addition of cellulose nanofibers into the starch matrix result in significant reduction in water solubility and water vapour permeability of the packaging films. The mechanical properties (elongation at break and tensile strength) of the films are improved significantly with incorporation of nano‐particles. Fourier transform infrared spectroscopy displays similar spectra for all tested samples due to the similar chemical nature of starch and cellulose. Similarly, differential scanning calorimetry analysis shows improved thermal stability of packaging films with the addition of nanofibers derived from banana peel cellulose. Moreover, scanning electron microscopy results show smooth surfaces and even distribution of particles and spaces in the matrix films as compared to the control. These results indicate the possible use of these packaging films in the food packaging industry thanks to their biocompatible, biodegradable, and non‐toxic characteristics and features. [ABSTRACT FROM AUTHOR]

A new compound (1) (named as artemceramide-B) together with eight known compounds (taraxerol (2), taraxerol acetate (3), β-sitosterol (4), stigmasterol (5), trans-ethyl caffeate, dracunculin (7), scoparone (8) and isoscopoletin (9) were isolated from an ethanolic extract of the roots of Artemisia incisa Pamp (Asteracae). The structures of the compounds were determined through IR, 1D NMR (¹H NMR, 13C NMR) and 2D NMR (COSY, NOESY, HSQC and HMBC) analyses. Accurate mass analyses were done with EI-MS, ESI-MS and acid methanolysis of compound 1 followed by GS-MS studies. The relative stereochemistry of artemceramide-B was determined by comparing its specific rotation and spectroscopic data with the literature. Compounds 1-9 were tested for their anti-bacterial potential against five bacteria strains; Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella pneumoniae, Bacillus subtilis and Escherichia coli. Compound 1 (new) (MIC: 0.0157, 0.0313 mg/mL) and 7 (MIC: 0.0815, 1.000 mg/mL) showed excellent activities against S. epidermidis and S. aureus while compound 9 showed excellent activities (MIC: 0.0700, 1.234, 1.890 and 2.286 mg/mL) against S. epidermidis, S. aureus, K. pneumoniae and E. coli, respectively. Compound 6 (MIC: 2.000 mg/mL) was found to be active against E. coli while neither of the compounds showed potential activity against B. subtilis. [ABSTRACT FROM AUTHOR]

Biodiesel fuel has shown great promise as an alternative to petro-diesel fuel. Biodiesel production is widely conducted through transesterification reaction, catalyzed by homogeneous catalysts or heterogeneous catalysts. Fourteen new organotin(IV) carboxylate complexes were preliminary screened for their catalytic activity in transesterification. The transesterification reaction, which is a major path to produce biodiesel, occurs between the triglyceride vegetable oils with alcohols to form esters (biodiesel) and glycerol. The present investigation involves the production of environmental-friendly heterogeneous catalyst, organotin(IV) carboxylates, for biodiesel production from corn oil. 83% Conversion of corn oil into biodiesel was obtained in the presence of the synthesized catalysts. Therefore, the newly synthesized organotin(IV) carboxylate complexes can be used as one of the best catalysts in future for the biodiesel synthesis. [ABSTRACT FROM AUTHOR]

A palladium complex, [KLCSS]2Pd (1), has been prepared by stirring sarcosine (HLH), KOH and CS2in methanol and subsequently treating with palladium(II) chloride. Six heterobimetallic derivatives of the type [R2(Cl)SnLCS2]2Pd (R = Me:2; Bu:3; Ph:4)/[R3SnLCS2]2Pd (R = Me:5; Bu:6; Ph:7) were also synthesized by stirring sarcosine (HLH) with KOH and CS2in methanol followed by an addition of R2SnCl2/R3SnCl and then PdCl2. FT-IR data demonstrated bidentate binding of dithiocarbamate and carboxylate with four- and five-coordinate environments around Pd(II) and Sn(IV) centers, respectively, in the solid state. UV–visible studies verified the square planar arrangement around Pd(II) in solution. The magnitude of2J(119Sn-1H) demonstrates a distorted trigonal bipyramidal geometry around tin(IV) in solution. Elemental analysis (C, H, N, and S), mass spectroscopic (EI-MS and ESI), and thermogravimetric analyses verified the chemical composition of products. Complexes1–7exhibited interaction with salmon sperm DNA (SS-DNA). The palladium complex1had shown higher potential to bind with SS-DNA and to inhibit the alkaline phosphatase when compared to the heteronuclear products (2–7). However, the antifungal/antibacterial activities of the bimetallic complexes (2–7) were significantly higher than the palladated derivative1. Thein vitrohemolytic activity investigations on human red blood cells showed that bimetallic derivative2with chlorodimethyltin(IV) exhibited the lowest hemolytic effects (17.55%), while5having trimethyltin(IV) center exhibited the highest hemolytic activity (78.64%). A palladium complex and its heterobimetallic (Sn, Pd) derivatives were synthesized and characterized by spectroscopic and thermogravimetric analyses. The palladium complex showed higher potential to bind with SS-DNA and to inhibit the alkaline phosphatase (ALPs) relative to the heteronuclear products (2–7). However, the bimetallic derivatives displayed significantly higher antifungal/antibacterial activities than the palladium complex1. [ABSTRACT FROM PUBLISHER]

The titled compound, 4-(5-chloro-2-hydroxyphenylamino)-4-oxobut-2-enoic acid was synthesized and characterized by various techniques like elemental analyses, FT-IR, NMR ( 1 H, and 13 C) and single crystal X-ray structural analysis. The appearance of the OH peak of the carboxylic acid in the FT-IR and NMR spectra conform the formation of the compound. A good agreement was found between the calculated values of C, H, N and found values in elemental analysis that show the purity of the compound. Protons H2 and H3 are in cis conformation with each other as conformed both from 1 H NMR as well as from single crystal X-ray analysis. The molecular structure of the title compound, C 10 H 10 NO 3 Cl, is stabilized by short intramolecular O H- - -O hydrogen bonds within the molecule. In the crystal structure, intermolecular N H- - -O hydrogen bonds link molecules into zigzag chains resulting in a dendrimer like structure. The title compound was screened for biological activities like interaction with DNA, cytotoxicity, antitumor and antioxidant activities. DNA interaction study reveals that the binding mode of interaction of the compound with SS-DNA is intercalative as it results in hypochromism along with significant red shift of 5 nm. It was also found to be effective antioxidant of 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and show almost comparable antioxidant activity to that of the standard and known antioxidant, ascorbic acid, at higher concentration. The antitumor activity data of the compound shows that it can be used as potent antitumor agent. [ABSTRACT FROM AUTHOR]

The methanolysis of jojoba oil has been studied in the presence of tin powder, dibutyltin diacetate (C 4 H 9 ) 2 Sn(OOCCH 3 ) 2 , dioctyltin diacetate (C 8 H 17 ) 2 Sn(OOCCH 3 ) 2 , dibutyltin oxide (C 4 H 9 ) 2 SnO, dioctyltin oxide (C 8 H 17 ) 2 SnO, diphenyltin oxide (C 6 H 5 ) 2 SnO, dibutyltin chloride dihydroxide (C 4 H 9 ) 2 Sn(OH) 2 Cl, butyltinhydroxide hydrate (C 4 H 9 )Sn(=O)OH. x H 2 O, Ni nanoparticles and Pd nanoparticles act as catalysts. Among these, 1 weight % of dibutyltin diacetate shows the maximum conversion. Then, methanolysis of sunflower oil, neem oil, rocket seed oil and linseed oil into methyl esters studied in the presence of 1% dibutyltin diacetate as a catalyst and was compared their percentage conversions. The experimental yield for the conversion of jojoba oil, sunflower oil, neem oil, rocket seed oil and linseed oil into biodiesel was found to be 71%, 51%, 50.78%, 40.90% and 39.66%, respectively. The experimental yield of the conversion of jojoba oil into methyl esters was found to be increased up to 96% by increasing reaction time, without emulsion formation. The synthesis of jojoba seed oil biodiesel (JSOB), soybean oil biodiesel (SOB), neem oil biodiesel (NOB), rocket seed oil biodiesel (RSOB) and linseed oil biodiesel (LSOB) was confirmed by NMR ( 1 H & 13 C) and FT-IR analyses of biodiesel. [ABSTRACT FROM AUTHOR]

Five zinc(II) complexes, [Zn(L1)2] (1), [Zn(L1)2(phen)H2O]·H2O (2), [Zn(L1)2(bipy)] (3), [Zn(L2)2] (4), and [Zn(L2)2(phen)] (5) (where L1 = 4-nitrophenylacetate, L2 = phenylacetate, phen = 1,10-phenanthroline and bipy = 2,2′-bipyridine), have been synthesized and characterized by elemental analysis, FT-IR, and multinuclear NMR. Complexes2,3, and4have been confirmed by single-crystal X-ray diffraction. In2and3, zinc is bonded monodentate to two carboxylates exhibiting distorted trigonal bipyramidal and tetrahedral geometries, respectively, whereas in4, the carboxylates are bridging bidentate in distorted tetrahedral geometry. The complexes have been screened for electro- and biological activities, including DNA interaction and enzyme inhibition studies. The effect of concentration of1–5on the activity of enzyme, alkaline phosphatase, showed that an increase in concentration of complex decreased the activity of the enzyme. Electrochemical behavior of HL1,2,and3was investigated by cyclic voltammetry and it was observed that ligand-centered electro-activity exhibits a proportionate change on complexation. The UV–visible spectroscopic and viscometric data indicate electrostatic and groove binding of the complexes with DNA. The binding constant and Gibb’s free energy values indicate the feasibility of the complex–DNA interaction and show potent biological activity of the complexes. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of six organotin(IV) complexes of 2-(4-ethoxybenzylidene) butanoic acid. [•] Spectroscopic characterization of synthesized complexes (1–6). [•] Single crystal analysis of complex 1. [•] Antimicrobial, cytotoxic and antitumor activities of complexes (1–6). [•] DNA interaction studies by UV–Visible spectrophotometry and viscometry. [ABSTRACT FROM AUTHOR]

Highlights: [•] Synthesis of potential bioactive Schiff base compounds. [•] Structural and spectroscopic characterization. [•] Biological activities. [•] Interaction with SSDNA via intercalative mode of interaction. [•] Excellent antioxidant activity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Composite of functionalized carbon nanotubes (CNTs) with CuO nanospheres is prepared. [•] Monodispersity, shape and size of CuO particles is specifically controlled to achieve high electrochemical performance. [•] The co-existence of CNTs and CuO matrix is clearly seen from TEM image. [•] High discharge capacity of 638mAh/g after 50 cycles. [•] 76% coulombic efficiency after 50cycles with a very small loss of charge capacity. [Copyright &y& Elsevier]

Abstract: NiO nanocrystals anchored on carbon nanotubes (CNTs) were fabricated via a polyvinylpyrrolidone assisted co-precipitation route. At a current density of 100mAg−1, the composite anode delivers an initial reversible capacity of 962mAhg−1 and retains the capacity to 601mAhg−1 after 50 cycles. In contrast, the reversible capacity of the pure NiO particles faded to 380mAhg−1 immediately and then gradually decreased to 278mAhg−1 after 50 cycles. The significantly improved electrochemical performance of the NiO/CNT nanocomposite is attributed to the formation of conductive networks by CNTs, and large surface areas of NiO nanoparticles grown on CNTs which stabilizes these nanoparticles against agglomeration and reduces the diffusion length for lithium-ions. The present results indicate that NiO/CNT nanocomposite has potential applications in lithium-ion battery anodes. [Copyright &y& Elsevier]

Abstract: In this study, functionalized carbon nanotubes (CNTs) with good conductivity and high surface area are anchored with mesoporous Co3O4 nanoparticles by a facile chemical co-precipitation method. Electrochemical characterizations show that Co3O4/CNT nanocomposite delivers a capacity of 873mAhg−1 after 50 cycles at a current density of 100mAg−1. When the current density is increased to 250, 350 and 500mAg−1, it still maintains a capacity of 895, 834 and 757mAhg−1, respectively. The high capacity, rate capability and good cycling ability of Co3O4/CNT nanocomposite are attributed to the intimate interaction between the CNTs and Co3O4 nanoparticles. The CNTs not only enhance the conductivity of Co3O4 nanoparticles but also improve the structure stability of Co3O4 nanoparticles. Furthermore, the mesoporous structure of Co3O4 nanoparticles is available to the transfer of electrolyte. Our results demonstrate that CNTs reinforced Co3O4 nanocomposite could be a promising anode material for high capacity lithium-ion batteries. [Copyright &y& Elsevier]

Metal oxides are well-known potential alternatives to graphite as anode materials of lithium-ion batteries, and they can deliver much higher reversible capacities than graphite even at high current densities. In this study, hexagonal disk-shaped ZnO are synthesized by a facile solution reaction of ZnCl2 and its composite is prepared in the presence of carbon nanotubes (CNTs). The as prepared ZnO/CNT composite has been characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, fourier transform-infrared spectroscopy and Rutherford backscattering spectroscopy. Electrochemical characterization by cyclic voltammetry, electrochemical impedance spectroscopy, and galvanostatic discharge/charge tests demonstrate that the conversion reactions in ZnO and ZnO/CNT electrodes enable reversible capacity of 478 and 602 mAh g-1, respectively for up to 50 cycles. Our investigation highlights the importance of anchoring of small ZnO particles on CNTs for maximum utilization of electrochemically active ZnO and CNTs for energy storage application in lithium-ion batteries. [ABSTRACT FROM AUTHOR]

The Internet of things and medical things (IoT) and (IoMT) technologies have been deployed to simplify humanity's life, which the complexity of communications between their layers was increased by rising joining the applications to IoT and IoMT-based infrastructures. The issue is challenging for decision-making and the quality of service where some researchers addressed the reward-based methods to tackle the problems by employing reinforcement learning (RL) algorithms and deep neural networks (DNNs). Nevertheless, satisfying its availability remains a challenge for the quality of service due to the lack of imposing a penalty to the defective devices after detecting faults. This paper proposes a quasi-mapping method to transfer the roles of sensors and services onto a neural network's nodes to satisfy IoT-based applications' availability using a penalty-backwarding approach into the NN's weights and prunes weak neurons and synaptic weights (SWs). We reward the sensors and fog services, and the connection weights between them when are covered the defective nodes' output. Additionally, this work provides a decision-making approach to dedicate the suitable service to the requester using employing a threshold value in the NN's output layer according to the application. By providing an intelligent algorithm, the study decides to provide a service based on its availability and updating initial information, including faulty devices and new joined components. The observations and results prove decision-making accuracy for different IoT-based applications by approximately 95.8–97% without imposing the cost. The study reduces energy consumption and delay by approximately 64.71% and 47.4% compared without using neural networks besides creating service availability. This idea affects deploying IoT infrastructures to decision-making about providing appropriate services in critical situations because of removing defective devices and joining new components by imposing penalties and rewards by the designer, respectively. [ABSTRACT FROM AUTHOR]

In this paper, targeting efficient authentication and key agreement in an IoT environment, we propose an Elliptic Curve Cryptography-(ECC) based lightweight authentication protocol called BCmECC which relies on a public blockchain to validate the users' public key to provide desired security. We evaluate the security of the proposed protocol heuristically and validate it formally, which demonstratse the high level of the security. For the formal verification we used the widely accepted formal methods, i.e., BAN logic and the Scyther tool. In this paper we also analyse the security of recently proposed blockchain-based authentication protocols and show that this protocol does not provide the desired security against known session-specific temporary information attacks in which the adversary has access to the session's ephemeral values and aims to retrieve the shared session key. In addition, the protocol lacks forward secrecy, in which an adversary with access to the server's long-term secret key can retrieve the previous session keys, assuming that the adversary has already eavesdropped the transferred messages over a public channel in the target session. The proposed attacks are very efficient and their success probability is '1', while the time complexity of each attack could be negligible. Besides, we show that BCmECC is secure against such attacks. [ABSTRACT FROM AUTHOR]

In deploying the Internet of Things (IoT) and Internet of Medical Things (IoMT)-based applications and infrastructures, the researchers faced many sensors and their output's values, which have transferred between service requesters and servers. Some case studies addressed the different methods and technologies, including machine learning algorithms, deep learning accelerators, Processing-In-Memory (PIM), and neuromorphic computing (NC) approaches to support the data processing complexity and communication between IoMT nodes. With inspiring human brain structure, some researchers tackled the challenges of rising IoT- and IoMT-based applications and neural structures' simulation. A defective device has destructive effects on the performance and cost of the applications, and their detection is challenging for a communication infrastructure with many devices. We inspired astrocyte cells to map the flow (AFM) of the Internet of Medical Things onto mesh network processing elements (PEs), and detect the defective devices based on a phagocytosis model. This study focuses on an astrocyte's cholesterol distribution into neurons and presents an algorithm that utilizes its pattern to distribute IoMT's dataflow and detect the defective devices. We researched Alzheimer's symptoms to understand astrocyte and phagocytosis functions against the disease and employ the vaccination COVID-19 dataset to define a set of task graphs. The study improves total runtime and energy by approximately 60.85% and 52.38% after implementing AFM, compared with before astrocyte-flow mapping, which helps IoMT's infrastructure developers to provide healthcare services to the requesters with minimal cost and high accuracy. [ABSTRACT FROM AUTHOR]

• A series of six organotin(IV) dithiocarbamate compounds have been synthesizes. • Compounds are well characterized by IR-Spectroscopy, 1H-, 13C- and 119Sn-NMR spectra. • Structure 1 is confirmed by X-ray crystallography. • All compounds exhibit pronounced activity against five different strains of bacteria. In extension with growing concern to develop new antimicrobial organometallic drugs, an attempt has been made to synthesize five new antimicrobial organotin(IV) carbodithioates with general formula, Me 2 SnClL (1), Me 2 SnL 2 (2), Et 2 SnClL (3), Et 2 SnL 2 (4) , Bu 2 SnClL (5) , Bu 2 SnL 2 (6) , (where L = Sodium 3,4-dihydroisoquinoline-2-(1H)-carbodithioate). Compounds have been synthesized by refluxing organotin(IV) chlorides with ligand in dry toluene for 7-8 h. Compound 1, 3 and 5 exhibited Penta coordination, while 2, 4 and 6 showed hexacoordination in solid state, as evident from the difference obtained between symmetric and asymmetric CSS stretches in IR spectra. Solid-state structures of 1 was further attested by single crystal analysis as distorted trigonal bipyramidal geometry. 1H-, 13C- and 119Sn- NMR spectroscopy was used to assess the geometry of the compounds in solution state. It was observed that 1, 3, 4 and 5 completely dissociated in solution and showed tetrahedral geometry, whereas 2 and 6 exhibit pentacoordinate geometry after partial dissociation in solution. The pronounced activity was observed for all the compounds against five different strains of bacteria. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] The synthesis, structural characterization and biological relevance of three paddlewheel binuclear carboxylate copper(II) complexes with the formulae [Cu 2 (2-nitrophenylacetate) 4 (H 2 O) 2 ]C 2 H 5 OH (1), [Cu 2 (diclofenate) 4 (acetone) 2 ] (2) and [Cu 2 (4-bromophenylacetate) 4 (pyridine) 2 ] (3) have been presented here. These complexes have been characterized using melting point, FTIR, absorption spectroscopy, electron spin resonance, cyclic voltammetry (CV) and single crystal XRD techniques, while their biological relevance was ascertained using molecular docking and DNA-binding studies. The FTIR spectra indicated all the important functionalities and the typical bridging bidentate coordination mode of the carboxylate moieties to the copper ion. Absorption spectroscopy yielded broad spectra corresponding to the 2 B 1g ground state and the singly occupied d x 2– y 2 orbital, typical of the copper(II) ion. This finding was confirmed by the ESR signals of complexes 1 – 3 , with g values of 1.44353, 1.44317 and 1.44324, respectively. CV yielded redox couples typical of complexes with Cu2+ metal centers. XRD showed that the copper(II) ions in all three complexes are coordinated by four carboxylate ligands, constituting the square base of the square pyramid around each copper ion. The apical position is occupied by water (1), acetone (2) or pyridine (3) molecules. Owing to the structural differences, 1 and 3 have inter-molecular interactions and growth along all three axes, while 2 has such interactions only along the a-axis, leading to preferential growth along this axis. The structural parameters of the structures are different from each other and have been correlated mutually as well as with their literature analogues. Their supra-molecular synthons have been presented and explained. A computational study by molecular docking using MOE (molecular operating environment) software has yielded docking scores of −8.4098, −8.0453 and −9.4098, respectively for 1 – 3. The DNA-binding activity, explored via spectrophotometry and cyclic voltammetry, yielded intrinsic binding constant values of the order of 104 M−1 for all the complexes, showing excellent binding potency with DNA. The structural as well as biological importance of the complexes has been manifested. [ABSTRACT FROM AUTHOR]

• Di- and tri-organotin(IV) carboxylate derivatives of 3-bromophenylacetic acid are reported. • The reported compounds were evaluated for their antibacterial and anticancer activities. • Molecular structures were determined by X-ray crystallography. • Hirshfeld surface analyses were performed to quantify and visualize any close intermolecular contacts in the molecular structures. In this article, we are reporting a series of di-and tri-organotin(IV) carboxylate complexes (1 – 4) derived from the reaction of sodium-3-bromophenylacetate (NaL) with (CH 3) 2 SnCl 2 , (C 4 H 9) 2 SnCl 2 , (CH 3) 3 SnCl and (C 4 H 9) 3 SnCl in dried toluene while refluxing for 8 h. The desired organotin(IV) derivative were analyzed by elemental analyzer, FTIR, NMR and single crystal XRD. The antimicrobial data against the tested bacterial strains follow the order: 2 > 4 > 3 > 1 > HL. The anticancer potential of the synthesized compounds was evaluated against the lung cancer cell line (A549) and normal lung fibroblast cell line (MRC-5) and it was observed that 4 was the highly cytotoxic against A549 while HL and 1 showed no cytotoxicity against MRC-5, neither at lower or higher concentrations. Di- and tri-organotin(IV) carboxylate derivatives of 3-bromophenylacetic acid have been synthesized. Complexes show higher in vitro antibacterial and cytotoxic activities than the free ligand itself. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: CuO-doped NiO (CuNiO) with porous hexagonal morphology is fabricated via a modified in-situ co-precipitation method and its nanocomposite is prepared with carbon nanotubes (CNTs). The electrochemical properties of CuNiO/CNT nanocomposite are investigated by cyclic voltammetry (CV), galvanostatic charge–discharge tests and electrochemical impedance spectroscopy (EIS). Since Cu can both act as conductor and a catalyst, the CuNiO/CNT nanocomposite exhibits higher initial coulombic efficiency (82.7% of the 2nd cycle) and better capacity retention (78.6% on 50th cycle) than bare CuNiO (78.9% of the 2nd cycle), CuO/CNT (76.8% of the 2nd cycle) and NiO/CNT (77.7% of the 2nd cycle) at the current density of 100mA/g. This high capacity and good cycling ability is attributed to the partial substitution of Cu+2 for Ni+2, resulting in an increase of holes concentration, and therefore improved p-type conductivity along with an intimate interaction with CNTs providing large surface area, excellent conduction, mechanical strength and chemical stability. [Copyright &y& Elsevier]

Abstract: Six new organotin(IV) complexes with general formula R3SnL/R2SnL2 where R=CH3 (1, 4), n-C4H9 (2, 5), C6H5 (3) or C8H17 (6) and L=3-[(3,5-dichlorophenylamido)]propanoic acid were synthesized and structurally characterized by elemental analyses, FT-IR, NMR (1H and 13C) spectral studies, and mass spectrometry. Spectroscopic results suggest that the ligand coordinate through oxygen atom of the carboxylate groups. Crystal structure of complex (2) exhibits distorted trigonal-bipyrimidal geometry around the tin atom while that of complex (3) exhibits tetrahedral geometry around the tin atom. Complexes (1–6) were screened for their antifungal and antibacterial studies and the results showed that the triorganotin(IV) complexes have higher activity against these microbes than the diorganotin(IV) complexes. The complexes bind to DNA via electrostatic interaction of Sn(IV)+ moiety with the negatively charged oxygen of phosphate group of DNA resulting in hyperchromism. [Copyright &y& Elsevier]

Abstract: The reaction of the sodium salt of para substituted phenyl acetic acid with CuSO4 in water and subsequent treatment with pyridine gives binuclear centro-symmetric complexes pyCu(R–C6H4CH2COO)4Cupy, where R=4-OMe (1) and 4-Cl− (2). The structures of both complexes were solved by X-ray single crystal analysis. The frame of the complexes is constructed as a dimeric ‘paddle-wheel’ with four carboxylate bridges. The apical position is occupied by a pyridine ligand and there is a Cu–Cu bond as well. The compounds demonstrated one-electron redox behavior and their peak currents were found to increase linearly with the square root of the sweep rate (ν 1/2). The overall electrode processes were found to be activation plus diffusion controlled. The values of the formal potential (E ´), diffusion coefficient (D) and heterogeneous rate constant (k°) were evaluated for the electroreduction process for both the compounds. [Copyright &y& Elsevier]

Abstract: A series of five monomeric and polymeric complexes: [Bu3Sn(C5H4O2S)] (1), [Me3Sn(C5H4O2S)] (2), [Cy3Sn(C5H4O2S)] (3), [Bu2Sn(C5H4O2S)2] (4), [Oct2Sn(C5H4O2S)2] (5) of thiophene-2-carboxylic acid have been synthesized by the reaction of ligand acid with di- organotin compounds for the complexes 4, 5 and its sodium salt with tri-organotin compounds for the complexes 1, 2 and 3 respectively, in suitable stoichiometries. All complexes have been structurally characterized by vibrational and magnetic resonance (1H, 13C NMR) spectroscopies. The structures of complexes (2), (3) and (4) have also been elucidated by X-ray crystallography. Relative potential has been assessed for their anti-bacterial, DNA protection and inhibitory assay against acetyl cholinesterase and butyryl cholinesterase. [Copyright &y& Elsevier]

In this work, laser induced plasma plume intensity and surface morphology of electron-defected silicon have been studied. For this purpose, the silicon (1 1 1) was irradiated with 15 MeV electrons at different doses (2000-10,000 cGy). The electron-defected silicon samples were analyzed by XRD and SEM, showing increase in number of defects (incubation or absorption centers) by increasing electron dose. Afterward, repetitive Nd:YAG laser pulses were applied to electron-defected silicon. The plasma plume due to each laser pulse was photographed by computer controlled image capture system. From the images, the integrated intensity of plasma plume was calculated by image processing software and plotted as a function of number of laser pulses. The plasma plume intensity was found to increase linearly with increasing pulse number for all silicon samples. The integrated intensity of plasma plume also increases for those silicon samples which were irradiated at higher electron doses. The surface morphology of laser-ablated electron-defected samples was examined through SEM showing different phenomena, like thermal, electronic and hydrodynamic sputtering processes along with the formation of cone, craters, re-deposition of material, heat affected zone (HAZ) and debris formation. [ABSTRACT FROM AUTHOR]

Abstract: A series of new organotin(IV) derivatives; Me3SnL (1), Bu3SnL (2), Ph3SnL (3), Me2SnClL (4), Bu2SnClL (5), Ph2SnClL (6), Et2SnClL (7) and Et2SnL2 (8) where L= N-(2,3-dimethylphenyl)piperazine-1-carbodithioate have been synthesized and characterized by various analytical techniques. Among these techniques, 1H and 13C NMR were carried out to asses solution structures whereas the solid state structures were confirmed by FT-IR and X-ray single crystal analysis (3, 5 and 8). Crystal structure of complex (3) and (5) showed distorted trigonal bipyramidal geometry and square pyramidal geometry, respectively. The inclination of the structure 5 towards square-pyramidal may be due to the presence of the Sn–Cl⋯HN-piperazine hydrogen bonds between the adjacent molecules. A supramolecular structure is shown by compound (8), with central tin atom exists in a distorted octahedral geometry. The antibacterial results indicated the profound activity of the compounds against various strains of bacteria. In addition to this, the triorganotin(IV) derivatives were found more active than diorganotin(IV) compounds. [Copyright &y& Elsevier]

Abstract: A series of mononuclear organotin(IV) complexes of the types, R3SnL {R=C4H9 (1), C6H11 (2), CH3 (3) and C6H5 (4)}, R2SnClL {R=C4H9 (5), C2H5 (7) and CH3 (9)} and R2SnL2 {R=C4H9 (6), C2H5 (8) and CH3 (10)}, have been synthesized, where L=4-(4-methoxyphenyl)piperazine-1-carbodithioate. The ligand-salt and the complexes have been characterized by Raman, FT-IR and multinuclear NMR (1H, 13C and 119Sn) spectroscopy and elemental microanalysis (CHNS). The spectroscopic data substantiate coordination of the ligands to the organotin moieties. The structures of complexes 4 and 6 have been determined by single-crystal X-ray diffraction and illustrate the asymmetric bidentate bonding of the ligand. The packing diagrams indicate O···H and π···H intermolecular interactions in complex 4 and intermolecular S2C···H interactions in complex 6, resulting in layer structures for both complexes. A subsequent antimicrobial study indicates that the compounds are active biologically and may well be the basis for a new class of fungicides. [Copyright &y& Elsevier]

Abstract: A new series of organotin(IV) complexes with 4-benzhydrylpiperazine-1-carbodithioate (L) were synthesised by the metathesis reactions of the ligand-salt with triorganotin(IV) chlorides and diorganotin(IV) dichlorides in the appropriate molar ratio. All the complexes were characterized by elemental analysis, Raman, IR, and multinuclear NMR (1H, 13C and 119Sn) spectroscopy. Solid-state studies (Raman, IR and X-ray analysis) confirmed the bidentate coordination of the ligand in all cases. Multinuclear NMR spectroscopy suggested that some tri- and diorganotin complexes reduce their geometry by one unit in solution. The τ values, 0.6 and 0.24 for chlorodibutyl- and chlorodiethyltin(IV) derivatives, respectively, authenticated the trigonal bipyramidal geometry for the first complex and distorted square-pyramidal geometry for the latter. The low τ value for the chlorodiethyltin(IV) complex is attributed to the additional Sn···Cl and Sn···S intermolecular interactions. The antimicrobial results indicated the compounds are active biologically. [Copyright &y& Elsevier]

A feature of diabetes is that the rate of protein glycation and the formation of advanced glycation endproducts (AGEs) increases spontaneously due to the abnormally elevated levels of sugar in the blood. The glycation of proteins is associated with a large number of late diabetic complications (retinopathy, neuropathy, atherosclerosis, end stage renal diseases, rheumatoid arthritis and neurodegenerative diseases). The increase in diabetic complications is a major cause of morbidity and mortality, which has increased significantly in the last two decades. Therefore, there is a considerable recent interest in the identification of lead molecules, which can inhibit the glycation process or slow it down considerably. A new class of anti-glycation agents has been identified, based on the spectrofluorimetric analysis of fluorescent advanced glycation endproducts (AGEs), benzenediol Schiff bases, and their structure-activity relationships have been studied. Some of these compounds have shown a promising anti-glycation potential in vitro. [ABSTRACT FROM AUTHOR]

A new series of di and tri-organotin(IV) compounds containing germanium with the general formula R4-nSnLn was synthesised by reaction of 3-triphenylgermanyl-3,3-dimethylpropionic acid with organotin(IV) oxides and organotin(IV) chloride in 2:1 and 1:1 molar ratio, respectively, where R = CH3, C2H5 , n-C4H9 , n-C8H17, and C6H5 n = 1 or 2 and L = triphenylgermanyl acid anion (GeC23 H23 O 2 ). These compounds were characterised by elemental analyses, FT-IR, multinuclear NMR ( 1 H, 13 C, 119 Sn), and mass spectrometry. The geometry around the tin atom was determined and compared in both solution and solid states. The spectroscopic results indicated that all the diorganotin(IV) compounds containing germanium possess trigonal-bipyramidal structures in solution and octahedral geometry in the solid state. A linear polymeric trigonal-bipyramidal structure in the solid state and a tetrahedral environment around the tin atom in non-coordinating solvents has been proposed for the triorganotin(IV) compounds. All synthesised compounds were tested in vitro against a number of microorganisms to assess their biocidal properties and to correlate them with the structures of the derivatives. These studies revealed that such compounds show promising activity against different strains of bacteria and fungi using the reference drugs imipenum and miconazole. [ABSTRACT FROM AUTHOR]

Abstract: Six organotin(IV) compounds with general formulae R3SnL, R=Me (2), Ph (6), R2SnL2, R=Me (1), Et (3), n-Oct (5), [((R2SnL)2O)2], R=Bu (4), L=6-nitropiperonylate, have been prepared. The newly synthesized compounds have been characterized by elemental analysis, FT-IR and multinuclear NMR (1H, 13C and 119 Sn). The structure of 4 has been determined by single crystal X-ray crystallography which is triclinic with the space group . The crystal structure contains centrosymmetric dimer distannoxane with planar central four-membered Sn2O2 core. The 6-nitropiperonylate ligand shows different modes of coordination with Sn, as a result the central Sn2O2 core is fused with two four-membered (Sn(1)–O(1)–Sn(2)–O(13)) and two six-membered (Sn(1)–O(13)–Sn(2)–O(8)–C(9)–O(7)) rings. The endocyclic Sn(2) is six coordinated in a skew trapezoidal bipyramidal environment while exocyclic Sn(1) is five coordinated with distorted trigonal bipyramidal geometry. The ligand acid and synthesized organotin compounds were also screened for antibacterial, antifungal, brine-shrimp lethality and potato disc antitumor activities. Results of bioassay demonstrate that organotin derivatives are in general more active than the ligand acid. [Copyright &y& Elsevier]

Coordination complexes of transition metals (Co, Ni, Cu, Fe, Cr, Ru, Ir, Mn, and Zn) with 6-methoxy-α-methyl-2-naphthalene acetic acid (Naproxen) and triphenylphosphine have been synthesized and characterized by conductance, elemental analysis, UV-Vis, AAS, and FT-IR spectroscopy. The elemental analyses data reveal the presence of 1:1 (metal : ligand) stoichiometry and the IR data suggest that naproxen functions as a bidentate ligand in coordination with transition metals. The anti-inflammatory assays of these complexes have significant effect. [ABSTRACT FROM AUTHOR]

The synthesis, spectroscopy, and antitumor behavior of organotin(IV) complexes of 2,3-methylenedioxyphenylpropenoic acid are described. The spectroscopic data indicate 1 : 2 and 1 : 1 metal to ligand stoichiometry in case of di- and trioganotin(IV) compounds and hypervalency of Sn(IV) in trigonal bipyramidal and octahedral modes. Mass spectrometric and elemental analysis data support the solid and solution spectroscopic results. The complexes have been evaluated in vitro against crown gall tumor and bio-activity screenings showed in vitro biological potential. The nature of covalent attachments (methyl, ethyl, n-butyl, phenyl, and n-octyl) of Sn(IV) played a decisive role for bioactivity. All the compounds have been studied in solution by NMR (1H, 13C) and also in solid state using FTIR, mass spectrometry, and by X-ray crystallography. The molecular structure of Et2Sn(IV) and Me3Sn(IV) derivatives confirm the behavior of di- and tri-organotin(IV) compounds in solid state. Mono-organotin derivatives are octahedral both in solid and solution. [ABSTRACT FROM AUTHOR]

Abstract: A series of organotin(IV) carboxylates, [Bu2SnL2] (1), [Et2SnL2] (2), [Me2SnL2] (3), [Bu3SnL] n (4), [Me6Sn2L2] n (5), [Ph3SnL] n (6) and [Oct2SnL2] (7), where L=O2CCH2C6H4OCH3-4, have been synthesized. These complexes have been characterized by elemental analysis, FT-IR and multinuclear NMR (1H, 13C and 119Sn). Based on spectroscopic results, the ligand appeared to coordinate to the Sn atom through COO moiety. Single crystal analysis has shown a bridging behavior of ligand in tributyl- and trimethyltin(IV) derivatives, and a chelating bidentate mode in diethyltin(IV) complex. Bioassay results have shown that these compounds have good antibacterial, antifungal and antitumor activity. The activity against prostate cancer cell lines (PC-3) decreased in the order 1 > 5 > 2 > 3 > 7. [Copyright &y& Elsevier]

New series of organotin(IV) complexes of aniline derivatives, R2SnL2 and R3SnL [where R = Me, n-Bu, Ph, n-Oct] have been synthesized by the reaction of HL¹ and HL² with respective organotin halides or oxides. Experimental details for the preparation and characterization (including elemental analysis, IR and multinuclear NMR (¹H-, 13C- and 119Sn-) spectra in CDCl3 and EI mass spectra of both series are provided. The binding sites of the ligands were identified by means of FTIR spectroscopic measurements. It was found that in all cases the organotin(IV) moiety reacts with the oxygen of COO- group to form new complexes. In the diorganotin complexes, the COO- group is coordinated to the organotin(IV) centres in a bidentate manner in the solid state. The 119Sn NMR data and the nJ(13C-119/117Sn) coupling constant support the tetrahedral coordination geometry of the organotin complexes in non-coordinating solvents. Biological activities (antibacterial, antifungal, cytotoxicity, antileishmanial and insecticidal) of these compounds are also reported. [ABSTRACT FROM AUTHOR]

New organotin(IV) complexes with 2-[(2',6'-diethylphenylamido)]benzoic acid (HL1) a nd 3-[(2' ,6'-diethylphenylamido)]propanoic acid (HL2) were synthesized by the reaction of di- and triorganotin salts in the presence of triethylamine as base or dioctyltin oxide using a Dean and Stark trap for the removal of azeotropic water. All complexes were characterized by elemental analysis, IR, NMR, and mass spectral studies, and proof that tin-ligand coordination involves only the carboxylate group and complexes show hexa-coordinated geometry in solid state. Multinuclear NMR data show that triorganotin complexes exhibit 4-coordinated geometry while diorganotin complexes show a coordination number greater than 4, probably 5 or 6 in solution state. These complexes were screened to check their antimicrobial activity in vitro. The complexes of 2-[(2',6'-diethylphenylamido)]benzoic acid (HL1) were also checked for their insecticidal and anti-leishmanial activity. All the complexes show significant activity with few exceptions. [ABSTRACT FROM AUTHOR]

Trimethyltin(IV) complex containing the carboxylate ligand 2,3-methylenedioxybenzoic acid (HL) have been synthesized and characterized insol utionstate by multinuclear NMR (1H, 13C and 119Sn) using the noncoordinating solvent and also in solid sate by FTIR, mass spectrometry, and X-ray crystallography. Spectroscopic data have shown that methylenedioxy moiety has not coordinated with tin atom; instead, the coordination site is a -COO group, which is proved by spectral and XRD data. The solid state structure shows the trigonal bipyramidal geometry with a space group P21/c. This compound was tested for its inv itro antitumor activity. [ABSTRACT FROM AUTHOR]

Dimethyl bis(4-methylpiperidine dithiocarbamato-S,S′)-tin(IV) was synthesized and characterized by elemental analysis, IR and mass spectrometry, multinuclear NMR (¹H- and 13C-NMR), and X-ray single crystal analysis. IR data showed that the ligand acts as a bidentate in the solid state. X-ray data showed the unsymmetrical nature of the ligand towards coordination to tin. It crystallized in the monoclinic P21/n space group. Its geometry is distorted octahedral. Antimicrobial activity data shows that the complex exhibits significantly more activity than the free ligand. [ABSTRACT FROM AUTHOR]

We prepared 8 new organotin compounds with the general formulae [R3SnL], where R =Me (1), Bu (2), Ph (3), and Cy (4) and [R2SnL2], where R = Me (5), Et (6), Bu (7), Oct (8), and L = piperonylic acid, and characterized them by elemental analyses, IR spectra, and multinuclear NMR (¹H, 13C, and 119Sn). The structure of 5 was confirmed by single crystal X-ray crystallography. The geometry around the tin atom was compared in both solution and solid state. Crystals of 5 are monoclinic with the space group P21/c. The tin geometry is skew trapezoidal bipyramidal, with 2 longer and 2 shorter Sn-O bonds; thus, the ligand chelates the Sn center in an asymmetric way. The synthesized compounds were also screened for antibacterial, antifungal, brine-shrimp lethality, and potato disc antitumor activity. [ABSTRACT FROM AUTHOR]

New compounds of bimetallic trimethyltin(IV) germapropionates have been synthesized and characterized by elemental analyses, FT-IR, and multinuclear nmr (1H,13C,119Sn) spectroscopies. These compounds show four-coordinated structure in solution and penta-coordinated structure in solid state. The crystal structure of representative compound, (CH3)3Sn(C22 H21 O2 Ge), shows one dimensional polymeric penta-coordinated structure in its solid state. The synthesized compounds were subjected for a bioassay screening and show promising antibacterial and antifungal activitie. [ABSTRACT FROM AUTHOR]

A series of five-coordinated germanium-substituted tricyclohexylantimony dipropionates have been synthesized and characterized by different instrumental techniques, such as elemental analyses, FT-IR, multinuclear NMR (¹H, 13C) and mass spectrometry. These compounds have also been screened against different microbes and they showed good activity against different bacteria that was comparable to the reference drugs. The crystal structure of the precursor (C6H11)3SbBr2 is reported here, which showed that the antimony atom in an asymmetric unit exists in trigonal bipyramidal geometry, having space group C2/c with the monoclinic crystal system. [ABSTRACT FROM AUTHOR]

New compounds of Bis-triorganogermyl(substituted) propionates of triarylantimony(V) with general formula (¹R3-GeCHR²CH2CO2)2SbAr3 have been synthesized and characterized by various techniques such as elemental analyses; FT-IR,¹HNMR, 13CNMR and mass spectrometry. All these compounds have distorted trigonal bipyramidal geometry around antimony in both solid states as well as in non-coordinated solvents. The single X-ray analysis of precursor triphenylgermyl-n-propyl propionic acid (Ph3GeCH-(n-C3H7)CH2COOH) have revealed dimeric structure of molecule through strong hydrogen bonding in conventional manner in which germanium has slightly distorted tetrahedral geometry. Selected numbers of compounds screened against different strains of bacteria and fungus show good activity. [ABSTRACT FROM AUTHOR]

In an effort to develop new organotin materials for investigation and biocidal evaluation, a series of compounds with the general formula R4-n-nSnLn (where R = CH3, n-C4H9, C6H5, C6H5CH2and L = 3-(N-naphthylaminocarbonyl)-2-propenoic acid) were synthesised, and characterised by elemental analysis, IR, multinuclear (¹H, 13C a nd 119Sn) NMR, 119mSn Mössbauer spectroscopy and mass spectrometry. The biological activity of these compounds against various bacteria and fungi was investigated. All of the compounds were active against the fungi tested with a few exceptions. These compounds also showed significant antibacterial activity. LD50 data show that the investigated compounds have significant toxicity. [ABSTRACT FROM AUTHOR]

A new series of bimetallic (Ge and Sb) compounds (1-7) was synthesized and characterized by elemental analyses, FT-IR, multinuclear NMR (¹H, 13C) spectroscopy and mass spectrometry. These techniques not only confirmed the formation of the compounds, but also revealed their trigonal bipyramidal geometry around antimony(V). Selected compounds were screened against different pathogens and showed promising antibacterial and antifungal activities. [ABSTRACT FROM AUTHOR]

Abstract: The use of metals in therapeutic drugs have become increasingly important over the last couple of decades resulting in a variety of exciting and valuable drugs such as cisplatin and auranofin. The coordination chemistry of metallodrugs is strongly dependent on understanding the thermodynamics (equilibria and structures) and kinetics of the reactions of metal complexes under physiological relevant conditions. In this review, biocoordination chemistry of several metallodrugs (gold antiarthritic, silver antibacterial, vanadium antidiabetic and bismuth antiulcer, drugs) and their possible mechanism of action has been described. Various structure–activity relationships and biochemical aspects of metal binding to cellular targets have been explained. Advances in the bioinorganic chemistry are crucial for improving the design of these compounds to reduce toxic side effects and to understand their mechanism of action. [Copyright &y& Elsevier]

Organotin carboxylates of the general formulae R2SnL2and R3SnL, where R = CH3, n-C4H9, C6H5, CH2C6H5 and L = 1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carboxylic acid (nalidixic acid), have been prepared. These compounds were characterized by FT-IR, mass and multinuclear NMR (¹H, 13C and 119Sn) spectroscopy. The geometry around the tin atom is compared both in solution and in solid state. These compounds were also screened for their antifungal and antibacterial activities. [ABSTRACT FROM AUTHOR]

Some new di- and tri-organotin(IV) derivatives of 4 different non-steroidal anti-inflammatory drugs (NSAIDs) with the general formulae R2SnL2 and R3SnL (where R = n-C8H17 and C6H5CH2) and L = 2-[(2,3-dimethylphenyl)amino]benzoic acid 2-(2-fluoro-4-biphenyl)propionic acid, 2-(4-isobutylphenyl) propionic acid and 2-(3-benzoylphenyl)-propionic acid were synthesized. These compounds were structurally characterized by infrared and multinuclear NMR (1H, 13C, 119Sn) spectroscopies and mass spectrometry. The isotopic effect of tin was studied by comparison of experimental data with the simulated isotopic pattern using the Chemtool software package. These compounds were also screened against different animal and plant pathogens to study their biological activity. LD50 data show that the reported compounds have significant toxicity. [ABSTRACT FROM AUTHOR]

Abstract: Nine organotin esters, Me2SnL2 1, Me3SnL 2, n-Bu2SnL2 3, n-Bu3SnL 4, Ph3SnL 5, (PhCH2)2SnL2 6, [(Me2SnL)2O]2 7, Et2SnL2 8 and n-Oct2SnL2 9, of (E)-3-(3-fluorophenyl)-2-(4-chlorophenyl)-2-propenoic acid, HL have been synthesized and characterized by elemental analysis, IR, Multinuclear NMR (1H, 13C and 119Sn) and mass spectrometry. The geometry around the tin atom has been deduced and compared both in solution and solid states. The crystal structure of compound 5 has been determined by X-ray single crystal analysis, which shows a tetrahedral geometry around the tin atom with space group . These compounds have also been screened for bactericidal, fungicidal activities and cytotoxicity data. [Copyright &y& Elsevier]