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Nano-sized binuclear Ag(I) complexes with thiocyanate and N-donor ligands such as adenine (ade), 1,10-phenanthroline (phen), and 1,8-diaminonaphthalene (dan) were synthesized and characterized by elemental (CHNS) and metal content analysis, FTIR, Raman, and 1H/13C-NMR spectroscopy, thermal analysis (TGA–DSC), XRF, PXRD, FESEM-EDX and TEM methods. The proposed molecular formulas for the synthesized complexes were [Ag2(ade)2(μ-SCN)2].2H2O, [Ag2(phen)2(μ-SCN)2].H2O, and [Ag2(dan)2(μ-SCN)2].3H2O derived from elemental and metal content analysis. The coordination of the ligands with the Ag(I) ion was confirmed by their FTIR and 1H-NMR spectral data. The SCN− ligand acts as a bidentate bridge between the two Ag(I) ions in all three complexes, binding through S or (N,S) donor sites. Additionally, the other ligands, adenine (ade), 1,10-phenanthroline (phen), or 1,8-diaminonaphthalene (dan), coordinate bidentately with the Ag(I) ion. The crystallite size was determined using the Scherrer equation from XRD data and found to be in the range of 21.46–67.60 nm. The complexes showed rod-like, block-like and spherical morphologies in SEM and TEM analysis and the average particle sizes of the complexes ranged from 56.70 to 81.12 nm. The Ag(I) complexes demonstrated notable antimicrobial activity against both gram-positive and gram-negative bacteria, as well as fungi. In brine shrimp lethality bioassays, the higher LC50 values of the complexes signified low toxicity to healthy cells. The complexes [Ag2(ade)2(μ-SCN)2].2H2O and [Ag2(dan)2(μ-SCN)2].3H2O exhibited IC50 values ranging from 50 to 1000 μg/mL, indicating significant free radical scavenging activities. The anticancer potential of Ag(I) complexes was evaluated using HeLa cervical cancer cell lines, revealing cytotoxic effects for the [Ag2(phen)2(μ-SCN)2].H2O complex. With an IC50 value of 58.80 ± 0.65 μg/mL, the complex displayed enhanced antiproliferation compared to cisplatin against the HeLa cell lines. [ABSTRACT FROM AUTHOR]

A silver–cytokinin complex filler was synthesized by a mild thermal process; then, the complex was mixed with an aqueous emulsion paint as an antimicrobial filler. Coating films were prepared by a typical method using 0.254 mm applicator. The results of antibacterial activity measurements indicated that the films exhibited strong activities against Escherichia coli and Staphylococcus aureus. Values of the antibacterial activity (n = 3) were 5.7 and 4.9, respectively. As for the mixture of five kinds of fungi, after cultivation (n = 5), no colony growth on the film surface was observed by microscopy. From the appearance of the film surfaces, it was revealed that the silver–cytokinin complex filler for emulsion paints possessed better paintability and transparency compared to a commercialized paint filler. [ABSTRACT FROM AUTHOR]

4-[(2-Diphenylphosphanylphenyl)methyleneamino]benzoic acid (HL) is obtained by the condensation of o-diphenylphosphinobenzaldehyde and p-aminobenzoic acid. The reaction of AgNO3 and HL affords complex [Ag2L2] · H2O (I). The structure of complex I is determined by X-ray structure analysis (CIF file CCDC 1575064), and its reflectance and luminescence spectra are studied. Binuclear complex I is a cyclic molecule in which each of two silver(I) atoms coordinates one phosphorus atom and one oxygen atom of two bridging anions L. Compound I is characterized by emission in a range of 430-740 nm at λexc = 340 and 395 nm. [ABSTRACT FROM AUTHOR]

Two new silver(I) complexes, [Ag(NBA)(DAC)] ( I) and [Ag(NBA)(DAB)] ( II), where NBA, DAC, and DAB are 3-nitrobenzoate, 1,2-diaminocyclohexane, and 1,4-diaminobutane, respectively, are prepared and characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction (CCDC nos. 1487698 ( I), 1487699 ( II)). The Ag(1) atom in I is in a linear coordination mode built by two N atoms from two DAC ligands. The Ag(2) atom in I is in a distorted triangular coordination mode formed by three O atoms from two NBA ligands. The Ag(1) atom in II is in a linear coordination mode formed by one O atom of a NBA ligand and one N atom of a DAB ligand. Crystal structures of both complexes are stabilized by hydrogen bonds and weak π···π interactions. The effect of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans is studied. [ABSTRACT FROM AUTHOR]

Starting from tripodal ligand tris-(methyl-imidazole) amine (1) the colourless complex tris-(methyl-imidazole)aminesilver(I)perchlorate (2) has been synthesized, characterized by IR, UV/Vis and HNMR spectroscopic studies and finally solid state structure has been established by single crystal X-ray diffraction studies. A single crystal X-ray structure determination revealed the formation of coordination polymer. The crystal structure possesses weak d-d 'argentophilic' interactions with Ag-Ag separation (3.348 Å). The weak luminance at 375 nm may be this Ag-Ag weak interaction. The molecule possesses weak H-bonding with C2 and C4H of imidazole with oxygen of ClO. [ABSTRACT FROM AUTHOR]

A novel ladder-like polymeric silver(I) complex, [AgL]•2 nHO, where L is 3-aminopyrazine- 2-carboxylate, was obtained by the reaction of 3-aminopyrazine-2-carboxylic acid and silver oxide in aqueous ammonia. The complex was characterized by elemental analysis, IR spectra and single crystal X-ray determination. The smallest repeat unit contains a [AgL] moiety and two water molecules. The Ag•••Ag distance is 3.176(1) Å. Each Ag atom is in a Y-shaped coordination, with one carboxylate O and two pyrazine N atoms from two ligands. In the crystal structure of the complex, the dinuclear silver moieties are linked through 3-aminopyrazine-2-carboxylate ligands, to form 1D ladder-like chain along the b axis. The water molecules are linked to the silver chain through hydrogen bonds. There are π•••π interactions between the chains. The complex showed effective cytotoxic property on human lung cancer cell line A549. [ABSTRACT FROM AUTHOR]

The novel derivatives of 1,2,3-triazole linked crown ethers were investigated towards silver(I) ion coordination. The NMR measurements in deuterated methanol in different ratios of ligand and silver cation were studied. The experiments were performed in order to examine the way of binding Ag(I) ion by the selected ligands. The results are presented for complexes with the Ag: L stoichiometry 0.5:1, 1:1 and 2:1, respectively. Depending on the type of crown ether moiety incorporated into the macrocyclic skeleton, interesting differences in the mode of stepwise coordination of the ion were noticed. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Modern lubricants face the task of providing lubrication over a wide range of temperatures, and extreme engine temperatures can exceed the thermal degradation limits of many engine oils. Soft metal additives can extend the life of engine oils at very high temperatures by providing solid lubrication to contacting surfaces. We report a new silver-organic complex which contains a high metal content and minimal supporting organic ligands. This silver pyrazole-pyridine complex is evaluated as a friction-reducing and anti-wear additive in engine oil at testing temperatures which thermally degrade the base oil. Two sets of ball-on-disk tests are performed: the first at a constant temperature of 200 °C and the second while increasing the chamber temperature from 180 to 330 °C. At 200 °C, the wear is considerably reduced compared with the base oil when the silver-organic additive is present at 2.5-5.0 wt%. Furthermore, the silver-based additive at 20 wt% in oil induces a remarkable friction reduction during the temperature ramp test, so much, so that the tribological transition from the oil as the primary lubricant to its degradation, and to the silver additive as the primary lubricant, is imperceptible. [ABSTRACT FROM AUTHOR]

The reaction of silver 4,4′-biphenyldicarboxylate with 1,3-diaminopropane (DAP) and 2-amino-5-methylpyridine (AMP) respectively results in the formation of two dinuclear silver(I) complexes: [Ag(DAP)](BPC)·2HO ( 1) and [Ag(BPC)(AMP)]·2HO ( 2), where BPC is 4,4′-biphenyldicarboxylate. The complexes are characterized by elemental analysis and X-ray crystallography. Complex 1 crystallizes in the triclinic system, P-1 space group, a = 8.585(2) Å, b = 8.849(2) Å, c = 9.890(3) Å, α = 107.893(3)°, β = 94.139(3)°, γ = 113.202(3)°, V = 640.9(3) Å, Z = 1. Complex 2 crystallizes in the triclinic system, P-1 space group, a = 11.818(3) Å, b = 13.132(4) Å, c = 13.281(4) Å, α = 92.571(4)°, β = 96.425(3)°, γ = 102.142(4)°, V = 1997.5(10) Å, Z = 2. Complex 1 consists of a macrocyclic dinuclear silver(I) dication, a 4,4′-biphenyldicarboxylate anion, and two water molecules of crystallization. Each Ag atom is in a linear coordination. Complex 2 consists of a dinuclear silver(I) complex molecule and two water molecules of crystallization. Each Ag atom is in a T-shaped coordination. The Ag...Ag separations are 5.127(2) Å in 1 and 3.172(2) Å in 2. [ABSTRACT FROM AUTHOR]

4-Chlorobenzoic acid reacts with silver oxide and 1-(2-aminoethyl)piperidine to give a dinuclear silver(I) complex, [Ag(CHClO)(CHN)]. The complex was characterized by elemental analysis and X-ray diffraction. The complex crystallizes in the triclinic space group P−1 with unit cell dimensions a = 6.8550(10), b = 8.7370(10), c = 13.859(2) Å, α = 73.213(3), β = 87.945(3), γ = 77.050(3)°, V = 774.09(18) Å, Z = 1, R = 0.0386, and wR = 0.0791. The dimeric Ag complex is located on an inversion center. The Ag atom in the complex is three-coordinated by two N atoms from two 1-(2-aminoethyl)piperidine ligands and by one O atom of a 4-chlorobenzoate ligand, forming a triangular coordination. In the crystal structure, the molecules are linked through intermolecular N-H···O hydrogen bonds, forming chains running along the a axis. The complex shows high cytotoxic property to both normal and carcinoma cells. Graphical Abstract: The synthesis, crystal structure and cytotoxic property of a new silver(I) complex has been presented.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A novel silver complex [Ag(dafo)(NO)] (dafo = 4,5-diazafluoren-9-one) was obtained. Its structure was determined by single crystal X-ray diffraction. The crystal structure shows that the Ag atom is in a five coordination environment. As far as the rigid of the dafo molecular is concerned, the structure is very remarkable. The work also studies the interaction between the complex and DNA by optical special and electrochemical methods. It is found that the action mode of the complex with DNA is intercalative. Graphical Abstract: A novel silver complex [Ag(dafo)(NO)] (dafo = 4,5-Diazafluorene-9-one) was obtained and its structure was determined by single crystal X-ray diffraction. The binding of the complex to calf thymus DNA has been investigated. It is found that the action mode of the complex with DNA is intercalative.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]