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Abstract: This study describes green-emitting Tb3+ or red-emitting Eu3+ doped calcium magnesium silicate phosphors by ultraviolet excitation at 335nm. The rare earth activated amorphous calcium silicate was prepared by a solution–combustion process at 600°C for 5–10min. The Ca2MgSi2O7 prepared using urea and ammonium nitrate has a tetragonal crystal structure. The resulting Tb3+-doped phosphor emitted green light centered at 544nm. The optimum excitation wavelength within the range 300–400nm was 335nm. The intensity and emitting wavelength of the Eu3+ doped samples can be controlled by annealing in a reducing or oxidizing environment, allowing light to be emitted as green or red. When the reducing environment is optimized, the emission spectrum of Ca2MgSi2O7:Eu2+ is a broad band at 497nm. [Copyright &y& Elsevier]

Abstract: YBO3:Tb3+ nanocrystalline phosphors were successfully deposited by a solution–combustion method, using rare-earth nitrates, urea and boric acid as starting materials. The crystal structure, morphology, chemical composition and photoluminescence properties of the films were investigated by X-ray diffraction (XRD) and atomic force microscopy (AFM). The results of SEM and XRD revealed that the powders were composed of spherical YBO3:Tb3+ nanocrystals with average grain size of between 50 and 100nm. The electron diffraction spectroscopy (EDS) confirmed the presence of the Y, B, O, and C. The XRD measurements revealed YBO3:Tb3+ (JCPDS:83-1205) structure when annealed at 1000°C for 2h. The YBO3:Tb3+ powders exhibited emissions at 490, 545 and 585nm, which were assigned to the 5D4–7F6, 5D4–7F5 and 5D4–7F4 transitions of Tb3+, respectively. Among them, the green emission at 545nm (5D4–7F5) was dominant. [Copyright &y& Elsevier]

A series of SiO2 nanostructures codoped with Eu3+; Mg2+ ions were obtained by a sol-gel method. The gels synthesized by the hydrolysis of Si(OC2H5)4, Eu(NO3)3·6H2O, and Mg(NO3)2 were heated in air at 600°C for 2 hours. Firstly, the total amount of Eu3+ ions was varied from 0 to 2.0mol% to investigate the effect of self-damping, while in the second case, the Eu3+ ions were kept constant in the experiment at 0.5 mol% total doping and Mg2+ ions varied. The samples were characterized by X-ray diffraction, TEM, EDS, and UV lamp-excited luminescence spectroscopy. The Eu3+ ions were homogeneously dispersed in the silica and interacting with the small (1-5 nm) amorphous silica matrix. Strong red emissions located at 614nm and 590nm for doped and codoped SiO2 were observed from the UV light excitation at room temperature. The composition of around 1.25 mol% Eu3+ gave highest emission intensity. SiO2; Mg2+ ions portray strongly enhanced emissions due to energy transfer from Mg2+ to Eu3+, which is due to radiative recombination. An increase in luminescence intensity was observed as the Mg2+-to-Eu3+ ratio increased for the range investigated. The results show Eu3+ ion is located inside or at the surface of disordered SiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

The title imino-phosphine compound, [PdCl2(C26H22NP)]·CH3CN, was prepared by reaction of N-[2-(diphenylphosphanyl)benzylidene]-2-methylaniline with dichlorido(cycloocta-1,5-diene)palladium(II) in dry CH2Cl2. The PdII cation is coordinated by the P and N atoms of the bidentate chelating ligand and by two chloride anions, generating a distorted square-planar coordination geometry. There is a detectable trans influence for the chloride ligands. The methyl group present in this structure has an influence on the crystal packing. [ABSTRACT FROM AUTHOR]

The title complex, [PdCl2(C20H20N2)]·CH3CN, was synthesized by the reaction of 2-[(2,6-diethylphenyl)iminomethyl]quinoline with dichlorido(cycloocta-1,5-diene)palladium(II) in dry CH2Cl2. The PdII ion is coordinated by two N atoms of the bidentate quinoline ligand and by two chloride anions, generating a distorted square-planar coordination geometry around the metal centre. There is a detectable trans influence for the chloride ligands. The crystal packing is characterized by π-π stacking between the quinoline rings. The use of acetonitrile as the crystallization solvent was essential for obtaining good-quality crystals. [ABSTRACT FROM AUTHOR]

In the title compound, [W(C5H5)(C3H6I)(CO)3], the W atom is coordinated by a cyclo­pentadienyl ligand, three carbonyl ligands and an iodo­alkyl chain in a distorted square-pyramidal arrangement. In the crystal structure, the molecules pack with the iodo­alkyl chains in non-interdigitated layers. [ABSTRACT FROM AUTHOR]

In Cp*Fe(CO)2( n-C3H6Br), where Cp* = η5-C5(CH3)5, the Fe atom is coordinated by a penta­methyl­cyclo­penta­dienyl ligand, two carbonyl ligands and a bromo­alkyl chain in a pseudo-octahedral arrangement. The molecular geometry is similar to that reported for a related structure, with the alkyl chain in an all- trans conformation and a Fe—C(alkyl) bond length of 2.057 (3) Å. In the crystal structure, the mol­ecules pack in layers. [ABSTRACT FROM AUTHOR]

Abstract: Efficient methodologies for the preparation of pentacyclo[5.4.0.02,6.03,10.05,9]undecane (PCU) amine derivatives are described via microwave-assisted synthesis. The obtained results revealed that microwave-assisted synthetic procedures under controlled conditions (power, temperature and time) are very convenient, high yielding, efficient and low-cost methods for the preparation of PCU amine derivatives. The new methods show several advantages including operational simplicity, good performance, significant reduction in reaction time, less by-product formation and easier purification. [Copyright &y& Elsevier]

Abstract: The reactions of the halogenoalkyl compounds [Cp(CO)3W{(CH2) n X}] (Cp=η5-C5H5; n =3–5; X=Br, I) and [Cp(CO)2(PPhMe2)Mo{(CH2)3Br}] with the nucleophiles Z =CN− and gave compounds of the type [Cp(CO)3W{(CH2) n Z}] for the tungsten compounds, whilst cyclic carbene compounds were obtained from the reactions of the molybdenum compound. The reactions of [Cp(CO)3W{(CH2) n Br}] (n =3, 4) and [Cp(CO)2(PPhMe2)Mo{(CH2)3Br}] with gave [Cp(CO)3W{(CH2) n ONO2}] and [Cp(CO)2(PPhMe2)Mo{(CH2)3ONO2}], respectively. The reaction of [Cp(CO)3W{(CH2) n Br}] with AgNO2 gave [Cp(CO)3W{(CH2) n NO2}]. In the solid state the complex [Cp(CO)3W{(CH2)3NO2}] crystallizes in a distorted square pyramidal geometry. In this molecule the nitropropyl chain deviates from the ideal, all-trans geometry as a result of short, non-hydrogen intermolecular N–O⋯O–N contacts. The reactions of the heterobimetallic compounds [Cp(CO)3W{(CH2)3}ML y ] {ML y =Mo(CO)3Cp, Mo(CO)3Cp∗ and Mo(CO)2(PMe3)Cp; Cp∗ =η5-C5(CH3)5} with PPh3 and CO were found to be totally metalloselective, with the ligand always attacking the metal site predicted by the reactions of the corresponding monometallic analogues above with nucleophiles. Thus the compounds [Cp(CO)3W{(CH2)3}C(O)ML z ] {ML z =Mo(CO)2YCp, Mo(CO)2YCp∗ and Mo(CO)Y(PMe3)Cp; Y=PPh3 or CO} were obtained. Similarly, the reaction of [Cp(CO)2Fe{(CH2)3}Mo(CO)2(PMe3)Cp] with CO gave only [Cp(CO)2Fe{(CH2)3C(O)}Mo(CO)2(PMe3)Cp]. Hydrolysis of the bimetallic compound, [Cp(CO)3W(CH2)3C(O)Mo(CO)(PPh3)(PMe3)Cp], gave the carboxypropyl compound [Cp(CO)3W{(CH2)3COOH}]. Thermolysis of the compound [Cp(CO)2Fe(CH2)3Mo(CO)3(PMe3)Cp] gave cyclopropane and propene, indicating that β-elimination and reductive processes had taken place. [Copyright &y& Elsevier]

The bond lengths and angles in the title compound, [W(C5H5)(C4H7O2)(CO)3], are as expected for a mol­ecule of this kind. The presence of the carboxyl­ic acid group leads, however, to the creation of hydrogen-bonded dimers consisting of pairs of centrosymmetrically related mol­ecules. [ABSTRACT FROM AUTHOR]

Obesity through its association with type 2 diabetes (T2D), cancer and cardiovascular diseases (CVDs), poses a serious health threat, as these diseases contribute to high mortality rates. Pharmacotherapy alone or in combination with either lifestyle modification or surgery, is reliable in maintaining a healthy body weight, and preventing progression to obesity-induced diseases. However, the anti-obesity drugs are limited by non-specificity and unsustainable weight loss effects. As such, novel and improved approaches for treatment of obesity are urgently needed. Nanotechnology-based therapies are investigated as an alternative strategy that can treat obesity and be able to overcome the drawbacks associated with conventional therapies. The review presents three nanotechnology-based anti-obesity strategies that target the white adipose tissues (WATs) and its vasculature for the reversal of obesity. These include inhibition of angiogenesis in the WATs, transformation of WATs to brown adipose tissues (BATs), and photothermal lipolysis of WATs. Compared to conventional therapy, the targeted-nanosystems have high tolerability, reduced side effects, and enhanced efficacy. These effects are reproducible using various nanocarriers (liposomes, polymeric and gold nanoparticles), thus providing a proof of concept that targeted nanotherapy can be a feasible strategy that can combat obesity and prevent its comorbidities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ligands synthesized in ethanolic solutions resulted in high yields. • Synthesis of Pd-complexes (C1 , C 2 and C3) via Pd(COD)Cl 2 resulted to high yields > 90% • Complex C3 had selective anticancer activities. • All the cell lines were highly susceptible to L1. Thiosemicarbazones (TSCs) have proven to be an important group of N S donor Schiff base ligands. Their biological activities, structural and donor diversities are often improved after coordination to a metal ion. In this work, novel thiophene-based thiosemicarbazone ligands; (E)-N,N'-dimethyl-2-((5′-methyl-[2,2′-bithiophen]-5-yl)methylene)hydrazine-1-carbothioamide (L1), (E)- N -ethyl-2-((5-phenylthiophen-2-yl)methylene)hydrazine-1-carbothioamide (L2) and (E)-2-((5′methyl)-[2,2′-bithiophen]-5-yl)methylene)- N -phenylhydrazine-1-carbothioamide (L3) were synthesized via condensation reaction. The corresponding complexes (C1 , C2 and C3) were synthesized by reacting the ligands with Pd(cod)Cl 2 under inert nitrogen environment. All the prepared ligands and complexes were characterized by using the FTIR, UV–Vis, 1H and 13C NMR, elemental analysis and single crystal X-ray crystallography on ligand L2. The anticancer activities of the complexes were investigated against human the Caco-2, HT-29, HeLa and non-cancerous KMST-6 cell lines. In the preliminary studies, unexpectedly of all ligands and complexes, L1 showed the best anti-tumor activities at 100 µg/mL with cell viabilities < 31% in all the cell lines. In general, cell lines were more susceptible to complexes than free ligands except for C1. Complex C2 had the highest activity among complexes; HeLa (8.4%), HT-29 (8.8%), Caco-2 (16.1%) and KMST-6 (24.5%) cell viabilities at a concentration of 100 µg/mL. The C3 complex demonstrated appreciable selectivity since it had minimal effect on non-cancerous KMST-6 cell line (76%) with relatively reduced cytotoxicity in other cells except in HeLa (0.0%). All the complexes prepared inhibited proliferation of HeLa cells. [ABSTRACT FROM AUTHOR]

The new compounds (5-methyl-2-thiophene-2-pyridyl(R))imine [R = methyl ( L1 ); R = ethyl ( L2 )] and (5-bromo-2-thiophene-2-pyridyl(R)imine [R = methyl ( L3 ); R = ethyl ( L4 )] were successfully synthesized via Schiff base condensation reaction and obtained in good yields. These potential ligands were reacted with [PdCl 2 (COD)] and [PdClMe(COD)] to give the corresponding complexes [PdCl 2 ( L )] ( L = L1 - L4 ; 1 – 4 ) and [PdClMe( L )] ( L = L1 - L4 ; 5 – 8 ). All compounds were characterized by IR, 1 H and 13 C NMR spectroscopy, elemental analysis and mass spectrometry. The molecular structures of 1 , 2 , 6 and 8 were confirmed by X-ray crystallography. The complexes were evaluated as catalyst precursors for standard Heck coupling reactions and showed significant catalytic activities that could be correlated with steric and electronic influences. [ABSTRACT FROM AUTHOR]

This paper explains one pot synthesis of type II water soluble L -cysteine capped cadmium telluride (CdTe) core shell quantum dots using cadmium acetate, potassium tellurite and L -cysteine as the starting materials. The reaction was carried out in a single three necked flask without nitrogen under reflux at 100 °C. Results from PL show a sharp absorption excitonic band edge of the CdTe core with respect to the core shell which loses its shoulder during the growth of the shell on the core. The PL spectra indicate a drastic shift in emission window of the core which is simultaneously accompanied by an increase in emission intensity. X-ray diffraction pattern confirms the formation of hexagonal phase for all samples. Some difference in absorption edges were observed due to varying synthesis time of CdTe NPs. The position of the absorption band is observed to shift towards the lower wavelength side for shorter durations of synthesis. [ABSTRACT FROM AUTHOR]

The new heterobimetallic complexes [(η5-C5H5)(CO)3W(CH2)nMo(CO)3(η5-C5H5)] n=3 to 6; [(η5-C5H5)(CO)3W(CH2)nMo(CO)3(η5-C5(CH3)5)] n=3, 4; [(η5-C5H5)(CO)3W(CH2)nMo(CO)2(PPhiMe3 − i)(η5-C5H5)] and [(η5-C5H5)(CO)2Fe(CH2)nMo(CO)2(PPhiMe3 − i)(η5-C5H5)] (n=3,4 and i=0 to 3) were synthesized by direct displacement of the iodide of a metallo-iodoalkyl complex with the appropriate anion. The complexes have been fully characterised by IR, 1H NMR, 13C NMR, COSY, HETCOR, HSQC and elemental analyses. X-ray diffraction studies were done on the complexes [(η5-C5H5)-(CO)3W(CH2)3Mo(CO)2(PPh3)(η5-C5H5)] and [(η5-C5H5)(CO)2(PPh3)Mo(CH2)3Fe-(CO)2(η5-C5H5)]. Both compounds form monoclinic crystals in the space group P21/c. The former has a W–C(alkyl) bond length of 2.316(7) A˚ and Mo–C(alkyl) bond length of 2.357(7) A˚ and the latter a Mo–C(alkyl) bond length of 2.374(2) A˚ and Fe–C(alkyl) bond length of 2.076(2) A˚. [Copyright &y& Elsevier]

• Acetyl methyl thiophene and cinnamal thiosemicarbazone Pd(II) complexes synthesized. • Compounds characterized by various spectroscopic techniques and elemental analysis. • Crystal structures of thiosemicarbazone ligands determined by single crystal XRD. • Anticancer activity against various human cancer cells was tested. • Selectivity for human cancer breast cells versus non-cancer breast cells tested. New thiosemicarbazone (TSC) ligands, AMT-C N-TSCH (L1), AMT-C N-TSC(CH 3) (L2), CIN-C N-TSCH (L3) and CIN-C N-TSC(CH 3) (L4) (AMT = 2-acetyl-5-methylthiophene, TSCH = thiosemicarbazide, TSC(CH 3) = 4-methyl-3-thiosemicarbazide, CIN = cinnamaldehyde) were synthesized by condensation reaction. The reaction of [PdCODCl 2 ] with the ligands L1 , L2 and L4 in the ratio 1:1 yielded complexes [Pd(L1)Cl] (C1), [Pd(L2)Cl 2 ] (C2), and [Pd(L4) 2 Cl 2 ] (C4) respectively (COD = 1,5-cyclooctadiene). The reaction of [Pd(COD)Cl 2 ] with CIN-C N-TSCH (L3) in 1:2 metal to ligand ratio yielded the complex [Pd(L3) 2 ] (C3). The ligands and the complexes were characterized by UV–Vis, FT-IR, NMR, elemental analysis and conductivity measurements. The ligand L1 coordinated to the metal in a tridentate fashion while L2 , L3 and L4 coordinated in a bidentate fashion. The ligands L1 and L3 coordinated to the metal as thiol anions while ligand L4 coordinated via the thione sulphur. Conductivity measurements of the metal complexes in dimethyl sulfoxide showed that the chloride ions complexes C1 , C2 and C4 are within the coordination spheres. The crystal structures of ligands L2 and L4 were obtained from a Bruker Smart KAPPA APEXII DUO diffractometer with graphite monochromated Mo Kαradiation (k = 0.71073 Å). Cytotoxic activity of the compounds was investigated against the human cancer cell lines; Caco-2 (colon), HeLa (cervical), Hep-G2 (hepatocellular), MCF-7 (breast), PC-3 (prostate) and MCF-12A (non-cancer breast) cells. The complex C2 exhibited excellent broad spectrum growth inhibition activity against all the human cell lines tested except for the non-cancer breast cells. All the metal complexes synthesized inhibited the proliferation of human prostate cancer cell. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) were synthesized using three red wine extracts (RW-Es); by varying temperature, pH, concentrations of RW-Es and gold salt. The RW-AuNPs were characterized by UV-vis, transmission electron microscopy (TEM), dynamic light scattering (DLS), and the Fourier Transform Infra-red Spectroscopy (FT-IR). Their stability was evaluated in water, foetal bovine serum (FBS), phosphate-buffered saline (PBS), and Dulbecco's Modified Eagle Medium (DMEM) by UV-Vis. The effect of the RW-Es and RW-AuNPs on KMST-6 cell cell viability was evaluated by MTT assay; and their wound healing effects were monitored by scratch assay. RW-AuNPs synthesis was observed by colour change, and confirmed by UV-Vis spectrum, with an absorption peak around 550 nm. The hydrodynamic sizes of the RW-AuNPs ranged between 10 and 100 nm. Polyphenols, carboxylic acids, and amino acids are some of functional groups in the RW-Es that were involved in the reduction of RW-AuNPs. The RW-AuNPs were stable in test solutions and showed no cytotoxicity to the KMST-6 cells up to 72 h. AuNPs synthesized from Pinotage and Cabernet Sauvignon enhanced proliferation of KMST-6 cells and showed potential as wound healing agents. Further studies are required to investigate the molecular mechanisms involved in the potential wound-healing effect of the RW-AuNPs.

The medical properties of metals have been explored for centuries in traditional medicine for the treatment of infections and diseases and still practiced to date. Platinum-based drugs are the first class of metal-based drugs to be clinically used as anticancer agents following the approval of cisplatin by the United States Food and Drug Administration (FDA) over 40 years ago. Since then, more metals with health benefits have been approved for clinical trials. Interestingly, when these metals are reduced to metallic nanoparticles, they displayed unique and novel properties that were superior to their bulk counterparts. Gold nanoparticles (AuNPs) are among the FDA-approved metallic nanoparticles and have shown great promise in a variety of roles in medicine. They were used as drug delivery, photothermal (PT), contrast, therapeutic, radiosensitizing, and gene transfection agents. Their biomedical applications are reviewed herein, covering their potential use in disease diagnosis and therapy. Some of the AuNP-based systems that are approved for clinical trials are also discussed, as well as the potential health threats of AuNPs and some strategies that can be used to improve their biocompatibility. The reviewed studies offer proof of principle that AuNP-based systems could potentially be used alone or in combination with the conventional systems to improve their efficacy., (© 2021. The Author(s).)

In the title compound, [PdCl2(C13H14N2S)], the Pd(II) ion is coordinated by two N atoms of the chelating bidentate ligand and two chloride anions, giving rise to a distorted square-planar geometry. The methyl-substituted thio-phene arm and the pyridine ring are connected to the metal cation through N atoms to form a six-membered chelate ring with a boat conformation, making the complex stable.

The title compound, [Fe(2)Pd(C(5)H(5))(2)(C(11)H(10)NO)(2)Cl(2)], exhibits a square-planar geometry at the Pd(II) atom, which is determined by inversion-related chlorine and ferrocenyl-imine mol-ecules across a center of symmetry. The ferrocenyl-imine moieties are trans to each other.

The structure of the title compound, [Mo(C(5)H(5))Cl(CO)(3)], reveals a pseudo-square-pyramidal piano-stool coordination around the Mo(II) ion, which is surrounded by a cyclo-penta-dienyl ring, three carbonyl groups and a chloride ligand.

In the title complex, [PdCl(2)(C(16)H(12)N(2))], the Pd(II) ion is coordinated by two N atoms [Pd-N 2.039 (2), 2.073 (2) Å] from a bidentate ligand and two chloride anions [Pd-Cl 2.2655 (7), 2.2991 (7) Å] in a distorted square-planar geometry. In the crystal, π-π inter-actions between the six-membered rings of the quinoline fragments [centroid-centroid distances = 3.815 (5), 3.824 (5) Å] link two mol-ecules into centrosymmetric dimers.

In the title compound, [Pd(CH(3))Cl(C(24)H(20)NPS)], the Pd(II) ion is coordinated in a distorted square-planar environment which includes the P and N atoms of the bis-chelating ligand. The thio-phene ring is rotationally ordered, unlike in the majority of crystal structures containing this group.

In the title compound, [PdCl(2)(C(11)H(10)N(2)S)], the Pd(II) ion is four-coordinated in a distorted square-planar environment by two N atoms of the chelating 2-[(thio-phen-2-ylmeth-yl)imino-meth-yl]pyridine ligand and two chloride anions. The thio-phene ring is rotationally disordered over two orientations in a 1:1 ratio. The crystal packing exhibits weak inter-molecular C-H⋯Cl and C-H⋯S hydrogen bonds.

In the title compound, [Pd(CH(3))Cl(C(25)H(22)NPS)]·0.5C(2)H(2)Cl(2), the Pd(II) atom is coordinated by the N,P-bidentate ligand, a methyl group and a chloride ion, generating a distorted square-planar PdCClNS coordination geometry, with the N and Cl atoms trans. The thio-phene ring is equally disordered over two orientations and the dichloro-methane solvent mol-ecule is disordered about an inversion centre.

The title compound, [W(C(10)H(14)N(2))(CO)(5)], contains five carbonyl ligands and a nicotine ligand in an octa-hedral arrangement around the tungsten atom. The metal atom shows cis angles in the range 87.30 (16)-94.2 (2)°, and trans angles between 175.2 (2) and 178.1 (4)°. The W-CO bond trans to the pyridine N atom [1.987 (6) Å] is noticeably shorter than the others, which range between 2.036 (3) and 2.064 (3) Å, possibly due to the well-known trans effect. The distance between the W atom and the pyridine N atom is 2.278 (4) Å.

The title compound, [WMoBr(C(5)H(5))(CO)(3)], is built up from a pseudo-square-pyramidal piano-stool coordination around the Mo atom, the important geometry being Mo-W = 2.6872 (7) Å, W-Br = 2.5591 (9) Å and Mo-W-Br = 158.35 (3)°.