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AbstractTwo new luminescent metal-organic frameworks (MOFs), [Cd3(AIBTD)4(HCOO)2(DMF)2] (Cd-MOF) and [Zn(AIBTD)(AA)] (Zn-MOF) (DMF = N,N-dimethylformamide, AA = acetate), were prepared by solvothermal reactions of 4-(7-(1H-imidazol-1-yl)benzo[c][1, 2, 5]thiadiazol-4-yl)benzoic acid (HAIBTD) possessing an emissive benzothiadiazole (BTD) moiety with cadmium nitrate and zinc nitrate, respectively. Single-crystal X-ray diffraction analyses show that Cd-MOF and Zn-MOF possess different two-dimensional (2D) networks and form three-dimensional (3D) frameworks with different stacking modes. Their fluorescence sensing ability for dopamine was studied and it was found that both Cd-MOF and Zn-MOF show fluorescence enhancement in DMF. The turn-on effect may be attributed to the absorbance-caused enhancement (ACE). The results indicate that Cd-MOF and Zn-MOF have potential as fluorescent sensors for dopamine. [ABSTRACT FROM AUTHOR]

TATB as an insensitive high explosive, has wide applications in both civil and military areas. High performance liquid chromatography (HPLC) is a crucial tool to analyze the purity for quality control of TATB. However, current HPLC method for TATB has several drawbacks resulted by its poor solubility. A deep eutectic solvent (CS-1) has high solubility toward TATB, so it has been used as the pretreatment solvent and mobile phase to develop a new HPLC method for TATB in this work. When CS-1 was used as the pretreatment solvent for TATB prior to HPLC analysis, it displayed greater efficiency, less dosage, and shorter time compared to conventional solvents such as dimethyl sulfoxide (DMSO) and dimethyl formamide (DMF). Compared to the pretreatment time of 240 min by using DMSO, the pretreatment time of TATB by using CS-1 is significantly shortened to 20 min. Meanwhile, the carrying capacity of mobile phase for TATB became stronger after CS-1 was added into the mobile phase. The concentration of TATB with 40 mg·100 mL−1 is successfully analyzed by the HPLC based on the mobile phase containing CS-1, which is 10 times higher than that of DMSO with 4.0 mg·100 mL−1. Therefore, a new HPLC method based on CS-1 as one of the deep eutectic solvents is first established to improve the efficiency and representation of analyzing high concentration of TATB. [ABSTRACT FROM AUTHOR]

Two solvent-controlled Cd(II) compounds, formulated as {[Cd2(Htdc)4(µ-imyp)(H2O)4]} (1), [Cd2(µ2-tdc)2(µ-imyp)(DMF)2(H2O)2]n (2) (H2tdc= 2,5-thiophenedicarboxylic acid, imyp = 4-imidazol-1-yl-pyridine and DMF = N,N-dimethylformamide) have been synthesized by reactions of Cd(NO3)2·4H2O and H2tdc with imyp in different solvents, respectively. Both compounds were then characterized by single-crystal X-ray diffraction and other physicochemical methods. In 1, partially deprotonated Htdc− anion as terminal ligand and µ-imyp ligand connect Cd2+ ions to generate a discrete structure. In 2, completely deprotonated µ2 – tdc2− anions and µ-imyp ligand link Cd2+ ions into a 1D double chain structure. Both compounds display 3D supramolecular structures through hydrogen bonding interactions. The results provided interesting insights into solvent effects on the structural formation of compounds 1 and 2. In addition, the solid-state photoluminescent properties of compounds 1 and 2 were also investigated. Two solvent-controlled Cd(II) compounds have been synthesized by reactions of Cd(NO3)2·4H2O and 2,5-thiophenedicarboxylic acid with 4-imidazol-1-yl-pyridine in the different solvents. One compound is a discrete structure, while the other compound has a 1D double chain structure. The results provided interesting insights into solvent effects on the structural formation of compounds. [ABSTRACT FROM AUTHOR]

The solid structure and diagnostics of dilapacholateaqua (dimethyl chloride) chromium (II) compound were analyzed by X-ray radiations. The crystal shape was analyzed and rectified with 5084 reflections using I39 (I) and strained in accordance with R1-factor of 0.0553 using full least-square matrix. The complex of Cr (II) have CrO6 octahedral arrangement, have two cis coordinated lapacholate anions at adjacent carbonyl [Cr–O bond] oxygens of phenyl group [Cr–O bond], H2O [d (Cr–Ow)] and a dimethylformamide (DMF) [d (Cr–O)] axially arranged. The complex crystal has been analyzed for their physicochemical and spectroscopic parameters. [ABSTRACT FROM AUTHOR]

In this work, two types of organic solvents: namely, dimethylformamide (DMF) and tetrahydrofuran (THF); were investigated individually to prepare graphene oxide (GO) based polystyrene (PS) nanocomposites. Both were effective exfoliation agents for GO nano-sheets using sonication process. However, DMF showed poor solubility for PS beads compared to THF due to its high boiling point, poor volatility, and the prevailing monomer–monomer interaction rather than monomer–solvent interaction. Hot pressing was not an efficient preparatory approach for those samples prepared by DMF. Hence, solution casting, and THF were adopted to prepare PS and its GO-based nanocomposites. (0.5 and 1.0) wt. % of GO were dispersed homogeneously in PS using different dispersive techniques. Range of properties were tested for the pure polymer and its GO-based nanocomposites prepared by THF. A good dispersion of GO nano-sheets in PS was observed by different microscopic techniques. A significant improvement of mechanical and thermo-mechanical (storage modulus) performances for the polymer nanocomposites (PNCs) were achieved compared to the pure polymer. Young's modulus for PS/GO nanocomposites was improved by 122% and 143% for GO loadings of 0.5 and 1.0 wt. %; respectively, and storage modulus for the nanocomposites recorded a considerable promotion compared to the pure polymer. [ABSTRACT FROM AUTHOR]

Vacuum membrane distillation (VMD) is an intriguing technique that has the potential to separate ethanol from an ethanol–water mixture. The goal of this work was to synthesize hydrophobic polyvinylidene fluoride–polytetrafluoroethylene (PVDF–PTFE) hybrid membranes that could be used in VMD. For membrane synthesis via phase inversion, the outcomes of different solvents, namely N-methyl-2-pyrrolidone (NMP), N,N-dimethyl acetamide (DMAc), and dimethylformamide (DMF), as well as PTFE loading in PVDF dope solution were also evaluated. The desired membrane hydrophobicity was ensured by increasing contact angle from 69° to 135°. The obtained average maximum pore size fell between 0.19 μm and 0.22 μm. Plenty of work has been done on how the performance of the synthesized membrane depends on the VMD operating parameters (ethanol concentration, flow rate, feed temperature, and permeate pressure). The highest separation factor of 37.68 was offered by the membrane synthesized using DMF as a solvent, while the membrane synthesized with the help of DMAc solvent had the most increased ethanol flux of 10.55 kg m−2 h−1. A thorough report has been made on understanding membrane morphologies and VMD performance. [ABSTRACT FROM AUTHOR]

Thiazol-based molecules have practically infinite biological implementation. Today, there are many medical applications for compounds containing the thiazole moiety owing to their presence in most clinically applied anticancer drugs, such as dasatinib, dabrafenib, ixabepilone, patellamide A and epothilone. In this study, the polycondensation, of a new group of thiazole-containing polyamides with the formulas PA1–4 was carried out by the interaction of 2-aminothiazole diphenyl sulfide and variable diacid chlorides in dimethyl formamide in the presence of potassium carbonate anhydrous as a catalyst. Fourier transform-infrared spectroscopy (FTIR) was initially used to figure out the PA1–4 structures, which were further characterized using solubility, gel permeation chromatography (GPC), X-ray diffraction analyses (XRD) and scanning electron microscopy (SEM). The solubility results revealed that the presence of heteroaromatic thiazole ring units and sulfur content in the polyamides main chain, made the solubility easier as it increases the chain packing distance. From the values of average molecular weight, it was clear that all synthesized polyamides have almost the same chain length which ranged from 37,561.80 to 39,827.66. Moreover, the thermogravimetric analysis (TGA) confirm that PA1–4 were thermally stable even at high temperatures especially the polyamides which were synthesized from aromatic diacid chlorides. Furthermore, the newly synthesized polyamides were investigated for their antimicrobial properties against different species of Gram-positive and Gram-negative bacteria and also against different fungi. The results revealed that compound PA2 showed the highest antibacterial activity. Also, their inhibitory activity against breast carcinoma cells (MCF-7 cell line) and colon carcinoma cells (HCT cell line) was evaluated. It was clear that there was an enhancement in the anticancer activity for the synthesized polyamides owing to the presence of the thiazole moiety as well as sulfur linkage. According to the results of the 50% inhibitory concentration (IC50), the synthesized polymers were found to be more active against the MCF-7 cell line than the HCT cell line. [ABSTRACT FROM AUTHOR]

The synthesis, characterization and crystal structure of a dimethylformamide (DMF) coordinated magnesium tetraphenylporphyrin, [Mg(TPP)(DMF)]·CH2Cl2 (1), is described. Theoretical studies including optimization of the geometry, simulation of the electronic spectrum and binding energy calculations were performed for the complexes using the DFT method to understand the axial coordination in magnesium porphyrins. To get insight into intermolecular interactions Hirshfeld surface analyses and plotting of the 2D fingerprint was performed. Antioxidant activity was measured for the complex which showed enhanced antioxidant activity in the presence of DMF. [ABSTRACT FROM AUTHOR]

Reductive coupling reactions are a facile and versatile way to make carbon – carbon bonds. However, most methods within this class of reactions makes use of reprotoxic, amide-based solvents. Mechanochemistry, a method that does not always require solvent, has been used for reductive coupling methods but still reports the use of at least some amide-based solvent for productive outcomes. This work presents the reactivity trends for the reductive homocoupling of aryl iodides when using various amounts of N,N-dimethylformamide (a commonly used amide-based solvent) and dimethyl carbonate (a greener alternative). The results of these experiments show that dimethyl carbonate may be used in sub-stoichiometric amounts with equal or greater efficiency to N,N-dimethyl formamide. Further, cross-electrophile coupling (XEC) is explored with various solvents, showing that N-butyl pyrrolidinone is efficient as a liquid assisted grinding solvent. These experiments show that under mechanochemical conditions, safer solvents are able to be used with no loss of efficacy for reductive coupling reactions. [ABSTRACT FROM AUTHOR]

Thermodynamics properties as well as infrared spectra of liquids can be determined using the quantum cluster equilibrium (QCE) theory. The QCE theory requires the knowledge of the structures of the clusters formed by the solvent molecules. In prelude to this determination, in this work, we studied the non-covalent bondings, the structures and the temperature-dependence of the clusters of dimethylformamide (DMF) from dimer to tetramer. To perform this study, we used classical molecular dynamics to sample initial geometries of DMF clusters. Then, optimisation of the geometries is carried out at the MP2/aug-cc-pVDZ level of theory. Besides, we carried out a quantum theory of atoms in molecule analysis. The results show that the structures of the DMF dimer exhibit a stacking configuration, and mainly stabilised by CH··· O hydrogen bondings. For the DMF trimer and DMF tetramer, the structures exhibit an amorphous behaviour. Moreover, it has been found that the CH··· O hydrogen bondings are the main non-covalent bondings in DMF clusters. CH··· C, CH··· N, N··· O, N··· C, C··· O and H··· H bonding interactions are also located in the studied DMF clusters. In addition, the temperature-dependence study shows that only isomers with relative energy within ∼ 1.0 kcal/mol have meaningful contribution to the population of DMF clusters. [ABSTRACT FROM AUTHOR]

The new compounds 6-methyl-8-morpholino-2H pyrimido[5',4':5,6][1,4]thiazino[3,2e][1,2,4]triazin-3(5H)-one (3a) and 6-methyl-8-(piperidin-1-yl)-2Hpyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazin-3(5H)-one (3b) were obtained from cyclocondensation of 6-bromo-1,2,4-triazine-3,5(2H,4H)-dione (1) with appropriate 5-amino-6methylpyrimidine-4-thiol (2a, b) in dimethylformamide and in the presence of potassium carbonate under reflux. Reaction of compounds (3a, b) with phosphorous oxychloride gave 4-(3-chloro-6-methyl-5H-pyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazin-8-yl)morpholine (4a) and 3-chloro-6-methyl-8-(piperidin-1-yl)-5H-pyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazine (4b). Nucleophilic substitution of chlorine atom of compounds (4a, b) with typical secondary amines in DMF and K2CO3 produced the new derivatives of the 3,8-disubstituted-5H-pyrimido[5',4':5,6][1,4]thiazino[3,2-e][1,2,4]triazine ring systems (5a–f). All the synthesized products were characterized and confirmed by their spectroscopic and microanalytical data. [ABSTRACT FROM AUTHOR]

Complexes [Zn(C6H5CONH2)2Br2] and [Zn((NH2)2CO)2Br2] were synthesized and characterized by elemental analysis, IR spectroscopy, and X-ray diffraction and compared to other complexes of zinc halides with benzamide and urea. In all complexes, the zinc ion has a tetrahedral coordination environment of two halide ligands and two oxygen atoms of two amide ligands. The structure of [Zn(C6H5CONH2)2Br2] (orthorhombic, Pna21, a = 29.207(6), b = 7.5826(14), c = 14.753(3) Å, Z = 8) is not isostructural to the chloride and iodide compounds. The [Zn((NH2)2CO)2Br2] complex (triclinic, P-1, a = 6.4435(9), b = 7.096(1), c = 11.7079(18) Å, α = 88.119(9)°, β = 77.005(9)°, γ = 66.320(8)°, Z = 2) is isostructural to [Zn((NH2)2CO)2Cl2], and they both differ from [Zn((NH2)2CO)2I2]. Dipole moments of complexes of various zinc halides with benzamide, urea, and dimethylformamide were calculated; they vary in the 9–13 D range. Complexes of zinc halides with amides were used to prepare films with the use of cellulose diacetate as a polymer matrix. Dielectric measurements showed the presence of a pronounced electret effect. [ABSTRACT FROM AUTHOR]

This study describes the in-situ modification of low molar ratio urea–formaldehyde (UF) resins with cellulose nanofibrils (CNFs) to improve the poor performance of resins synthesized with different methods (Synth 1 and Synth 2) when adding second urea. UF resins were in-situ modified with CNFs dissolved in a mixture of dimethyl sulfoxide (DMSO) and dimethylformamide (DMF) during the alkaline reaction step. Results showed that CNF addition enhanced the resin properties, such as shorter gelation time, faster curing rates at low activation energy, higher tensile shear strength (TSS), and lower formaldehyde emission (FE), compared to those of neat resins. The dry and wet TSS values of plywood bonded with UF resins modified with 3% CNFs synthesized using Synth 2 increased by 30% and 42%, respectively, and the FE value was decreased by 22% and 42%, respectively. These results reveal that in-situ modified UF resins with CNFs showed better performance than neat UF resins and that Synth 2 was more favorable than Synth 1. [ABSTRACT FROM AUTHOR]

Effects of aging temperature and time on dilute solution properties of polyacrylonitrile (PAN) in N,N-dimethyl formamide (DMF) and dimethyl sulfoxide (DMSO) were characterized. In DMF, the intrinsic viscosity ([η]) showed little time-dependent change between 30 and 50 °C. Above 50 °C, however, the [η] was gradually decreased with aging time, suggesting the coil shrinkage. Such phenomenon indicated the deterioration of polymer solubility; i.e., lower critical solution temperature behavior. However, in DMSO which produced better solubility than DMF, the time-dependent decrease of the [η] and related LCST behavior was observed above 90 °C. [ABSTRACT FROM AUTHOR]

Driven by an interest in the impact of the para-substituent of calix[4]arenes on metal complexation and structural chemistry, studies of p-cyclohexylcalix[4]arene (L) have been carried out. The 1:1 dichloromethane and dimethylformamide solvates were found to be isostructural, and different to the typical bilayer structure often observed for p-t-butylcalix[4]arene solvates. The methanol solvate, in contrast, does form a bilayered structure but is also a 1:1 solvate, unlike the p-t-butylcalix[4]arene·2MeOH system. Lanthanoid complexation was investigated, resulting in the structural characterisation of two different DMF solvates of a 2:2 dimeric europium complex, Eu2(L–3H)2(DMF)4. A tetrazole derivative, 5,11,17,23-tetracyclohexyl-25,27-dihydroxy-26,28-bis(tetrazole-5-ylmethoxy)calix[4]arene, has been synthesised via the intermediate 5,11,17,23-tetracyclohexyl-25,27-dihydroxy-26,28-dicyanomethoxycalix[4]arene, with the latter compound being structurally characterised. Attempts to isolate lanthanoid clusters supported by the tetrazole derivative under conditions known to form Ln19 clusters with the p-t-butyl analogue were unsuccessful, resulting only in isolation of the ligand from the reaction mixture. [ABSTRACT FROM AUTHOR]

A search of the published chemical and engineering literature found enthalpy of solution data for an additional 71, 39 and 46 organic compounds dissolved in heptane, cyclohexane and N,N-dimethylformamide, respectively. The newly retrieved enthalpy of solution data was converted to enthalpy of solvation values, ΔHsolv, using standard thermodynamic relationships. Updated Abraham model correlations were derived for describing gas-to-heptane, gas-to-cyclohexane and gas-to-N,N-dimethylformamide enthalpies of solvation by combining the additional values to our existing heptane, cyclohexane and N,N-dimethylformamide ΔHsolv databases. The updated Abraham model correlations for heptane, cyclohexane and N,N-dimethylformamide described the observed ΔHsolv values to within overall standard deviations of less than 3 kJ/mole. [ABSTRACT FROM AUTHOR]

A Capillary Break-up Extensional Rheometer (CaBER) was modified to enable measurements of the axial force in combination with the related displacement. This makes it possible to determine the separation energy W s e p N , the tackiness, of a polymer solution between two parallel plates with the CaBER. Separation energies of solutions of linear polystyrene, comb polystyrene and linear poly(methyl methacrylate) in dimethylformamide were measured as model systems. For linear polymers at a critical polymer concentration, there was a drastic change in slope of the separation energy W s e p N c . This critical concentration was shown to be the minimum concentration at which continuous bead-free fibers could be electrospun. [ABSTRACT FROM AUTHOR]

The reaction of cobalt(II) acetate with 2-iodoterephthalic acid and 1,10-phenanthroline (phen) in N,N-dimethylformamide (DMF) leads to formation of two products, hexakis(N,N-dimethyl-formamide-κO)cobalt(II) bis(iodide) (1) and MOF [Co(TP)(phen)·2DMF·2H2O] (2), where TP is terephthalate dianion. Compound 1 crystallizes in the monoclinic space group Р2 1/с with cell parameters a = 14.2974(4) Å, b = 10.7983(4) Å, c = 20.6437(9) Å, V = 3183.23 Å3. The MOF was characterized by elemental analysis, infrared spectrometry, X-ray diffraction, scanning electron microscopy, thermogravimetry, and volumetric nitrogen adsorption/desorption. The sample has permanent porosity and a microporous structure with a large surface area corresponding to the adsorption type I. Thermolysis of 2 leads to the formation of nitrogen-doped carbon nanomaterials Co/CoO@C. [ABSTRACT FROM AUTHOR]

In this work, 5,5′-carbonyldiisophthalic acid (H4cipa) was used as a ligand to react with Zn(NO3)2·6H2O in a mixed solvent of DMF and water to prepare a new metal-organic framework (MOF) with the chemical formula of [Zn2(cipa)(H2O)2](DMF) (1). Due to its O donor sites within the one-dimensional channels and high density of open metal sites, the activated 1a was applied as a heterogeneous catalyst for the formation of C–C bonds of carbonyl compounds in the absence of solvents, which shows high efficiency and size-selectivity. Furthermore, the possible reaction mechanism has been proposed based on the experimental results. The treatment activity of the new compound on the Mg63 osteosarcoma cell line was evaluated and the possible mechanism was discussed. First, flow cytometry was performed to detect the levels of the Mg63 cancer cells' autophagy levels after indicated compound treatment. Next, real time RT-PCR assay was further conducted to measure the relative expression levels of the autophagic genes under treatment. [ABSTRACT FROM AUTHOR]

A new, highly sensitive and selective chemosensing method has been developed for the detection of cyanide ion using benzamide hydrazone receptors (R1-R4). The sensing ability of these compounds towards CN− in the presence of Br −, HSO4−, Cl−, OH−, I−, F−, AcO−, NO2− and NO3− in DMF and DMF-Aqueous mixture (DMF:H2O, 9:1 v/v) was investigated. The binding characteristics of the probe with cyanide ions carried out by 1 H NMR titrations indicated the deprotonation of N-H group through H-bond interactions between benzamide hydrazones and cyanide ions; it has been theoretically supported by DFT. The binding constant (Ka) and stoichiometry of the host–guest complex formed was calculated by the Benesi–Hildebrand (B–H) plot, and strong interaction of the probe with CN- ions forming a 1:2 binding stoichiometry has been noted in this study. In a DMF and aqueous medium for CN− ion, the lower limit of detection (LOD in ppm) is compared to the limit of quantification (LOQ in ppm), which is quite better in terms of sensitivity. [ABSTRACT FROM AUTHOR]

Sodium diclofenac is an analgesic drug commonly used in current therapeutics. Solubility data of this drug in aqueous cosolvent mixtures are not abundant. The main objective of this research was to determine and correlate the equilibrium solubility of sodium diclofenac in some {cosolvent (1) + water (2)} mixtures at 298.2 K. Cosolvents were formamide, N-methylformamide, and N,N-dimethylformamide. Classical shake-flask method was used to determine isothermal solubility. Drug concentration measurements were performed by means of electrical conductivity determinations after adequate aqueous dilutions. Solubility of sodium diclofenac increases non-linearly with the addition of cosolvent to water in almost all mixtures compositions. Higher solubility values were found in {N,N-dimethylformamide (1) + water (2)} mixtures. Jouyban-Acree model correlates solubility values with the mixtures composition for all cosolvent systems. Furthermore, the apparent specific volume of this drug was also calculated from density and mixtures compositions. [ABSTRACT FROM AUTHOR]

Treatment of [Ru(NO)Cl3(PPh3)2] with one equivalent of 3,5-dibromosalicylaldehyde in the presence of triethylamine gave the ruthenium(II) nitrosyl complex [Ru(NO)(κ2-C,O-salBr2)Cl(PPh3)2] (1). Interaction of [Ru(bpy)2Cl2]·2H2O with one equivalent of 5-chlorosalicylaldehyde in ethanol/N,N′-dimethylformamide afforded the bis(2,2′-bipyridine)ruthenium(II) complex [Ru(bpy)2(κ2-O,O-salCl)](PF6) (2). Complexes 1 and 2 were well characterized by infrared, proton nuclear magnetic resonance spectroscopies along with microanalyses and their molecular structures were determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

The liquid structure of the commonly used solvents dimethylformamide (DMF) and dimethylacetamide (DMA)were measured using state-of-the-art state neutron diffraction augmented with isotopic substitution (NDIS) and interpreted with empirical potential structure refinement (EPSR). Both solvents are found to develop rich local ordering with similar local packing densities, though with differences related to their three-dimensional molecular structure. While DMF's dipole preferentially orientates anti-parallel to maximise hydrogen bonding, DMA favours parallel arrangement maximising non-directional dispersive forces. The highly-developed local orientational structure found in these solvents rationalises their ability to solvate a range of charged and neutral nanomaterials and highlights that the understanding of nanomaterial dispersions is a multi-body problem in which the geometry of the molecule, as well its dipole moment, must be incorporated. [ABSTRACT FROM AUTHOR]

Synthesis of [Co(L)(H2O)(HOCN(CH3)2)](ClO4) (where L denotes N,N′-bis(3-methoxysalicylidene)-1,2-diaminopropane) was reported. The complex was characterized by 1H NMR, elemental analysis, IR and UV–vis spectroscopy and the structural features have been solved by X-ray crystallography. The crystal structure analysis showed that the arrangement around cobalt atom is octahedral with two imine nitrogen atoms (N1 and N2) and two oxygen atoms of hydroxyl groups (O2 and O3) at equatorial positions and an aqua ligand and a DMF ligand at the axial positions. The hydrogen-bonding interactions between coordinated H2O and phenoxo/methoxy oxygens connect the complex molecules in dimers. Interaction of the complex with FS-DNA and protein (BSA) was explored by fluorescence and absorption spectroscopy, viscosity measurements, circular dichroism (CD), cyclic voltammetry (CV) and agarose gel electrophoresis. According to the Kb value about 103, the complex is moderately bound to DNA. The complex interacts with protein (BSA) by both static and dynamic quenching. According to cleavage experiment, the complex destroys annular DNA and causes double strand break. Molecular docking was done to achieve detailed binding information of the complex to DNA and BSA. Moreover, cytotoxic activity was evaluated by MTT assay. The complex has low toxicity against the MCF-7 and LNCaP cancer cells. [ABSTRACT FROM AUTHOR]

Nano-TiO2/poly(methylmethacrylate) nanofibres were prepared by electrospinning with poly(methylmethacrylate) (PMMA) and anatase nano-TiO2 as main materials which were blended mechanically and dissolved in dimethylformamide (DMF) and ethyl ethanoate (EA) solvent. The nanofibres morphologies and physical states were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetry analysis (TG), fourier transform infrared (FTIR) spectroscopy and UV–visible (UV–Vis) spectroscopy. Scanning electron microscopy observations revealed that when the content of TiO2 was 5%, nano-TiO2/poly(methylmethacrylate) nanofibres had the minimum average diameter which was 409 nm. Results from FTIR, XRD and TG suggested that anatase nano-TiO2 had been successfully introduced to the PMMA matrix and TiO2/PMMA nanofibres had good thermal stability within 300 °C. Results from UV–Vis suggested that when 10% of anatase nano-TiO2 was added, the photocatalytic decomposition of methyl orange was 50% higher than that of pure PMMA nanofibres under sunlight irradiation for 5 h. [ABSTRACT FROM AUTHOR]

R-TiO2/PMMA nanofibers were prepared by electrospinning with poly(methylmethacrylate) (PMMA) and rutile nano-TiO2 (R-TiO2) as main materials which were blended mechanically, and dimethylformamide (DMF) and ethyl ethanoate (EA) as component solvent. The nanofibers morphologies and physical states were investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetry analysis (TG), fourier transform infrared (FTIR) spectroscopy and UV-visible (UV-Vis) spectroscopy. Scanning electron microscopy observations revealed that with the increase of DMF proportion in solvent the fibers average diameter gradually decreased, with the increase of EA ratio in solvent more micropores emerged, and as the content of R-TiO2 increased, the fibers average diameter decreased initially, then followed by an increase. When the content of R-TiO2 was 5%, the minimum fibers average diameter was 436 nm. Results from FTIR, XRD and TG suggested that rutile nano-TiO2 had been successfully introduced to the PMMA matrix and R-TiO2/PMMA nanofibers had good thermal stability, and heating weightlessness was less than 2% in the 300 °C. Results from UV-Vis suggested that when 10% of rutile nano-TiO2 was added, the degradation of methyl orange was 30% higher than that of pure PMMA nanofibers under sunlight irradiation. [ABSTRACT FROM AUTHOR]

In an attempt to develop alternative process that meet the prescribed levels and green-technology criteria in gas-oil refining, N,N-methylpyrrolidone (NMP), dimethylformamide (DMF) mixed solvents under microwave-radiations (MW) were tested for the gas-oil desulfurization (EDS), denitrification (EDN) and dearomatization (EDA). In optimal conditions the gas-oil EDS-efficiency via MW can reach as high as 99.1% within 5 min at 500 W in three stages, which is much higher than EDS without MW (88.5% within 15 min) or than those of ionic liquids. The NMP/DMF/EG can be reused for multi-cycles before being regenerated by adsorption method. This study will provide useful information for future industrial application. [ABSTRACT FROM AUTHOR]

The article offers information on the Cabozantinib, a small molecule inhibitor of the tyrosine kinases c-Met and VEGFR2; and mentions a new and practical synthetic route of cabozantinib (1), adopting a reduction cyclization process to prepare the key 4-hydroxyquinoline compound 6 from 13.

In the present investigation, the bioactive azo-dye ligand 1,5-dimethyl-4-[(3-methyl-5-oxo-1-phenyl-4,5-dihydro-1H-pyrazol-4-yl)diazenyl]-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (L) and its transition metal complexes have been synthesized and characterized by various physical and spectroscopic techniques to elucidate their geometrical structures. The molar conductivity measurements confirmed the non-electrolytic nature of the complexes. EPR spectroscopy indicated that the metal complexes are monomeric in nature and exhibited octahedral geometry. The redox behavior of the copper complex was studied by the cyclic voltammetric technique in DMF solution and the complex showed well-established redox behavior at a scan rate of 0.05 V s−1. The antimicrobial activity of the ligand and its metal complexes were screened against Escherichia coli, Bacillus subtilis, Aspergillus niger, and Candida albicans, and the results indicated increased activity after coordination of the ligand to the metal ions. The metal complexes exhibited enhanced antitubercular activity after chelation against M. tuberculosis. The DNA-binding experiments showed that the ligand and its metal complexes showed effective binding properties through intercalative mode against CT-DNA. All the synthesized molecules showed partial cleavage of supercoiled plasmid pUC18 DNA. [ABSTRACT FROM AUTHOR]

This study reports a novel method for the synthesis of a new class of pyrazole thioglycosides 7a-h as pyrazomycin analogues. These series of compounds were designed through the reaction of sodium 2-cyano-3-oxo-3-(4-substitutedphenylamino)prop-1-ene-1,1-bis(thiolate) salts 2 with phenyl hydrazine in ethanol at room temperature to give the corresponding sodium 5-amino-4-(substitutedphenylcarbamoyl)-1-phenyl-1H-pyrazole-3-thiolates 3a-d. The latter compounds were treated with tetra-acetylated glycosyl bromides 4a,b in DMF at ambient temperature to give the corresponding pyrazole thioglycosides 6a-h. Treatment of pyrazole salts 3a–d with hydrochloric acid at room temperature afforded the corresponding 3-mercaptopyrazole derivatives 5. The latter compounds were treated with tetra-acetylated glycosyl bromides 4 in sodium hydride-DMF to tolerate the S-glycosyl 6a-h compounds. Ammonolysis of the latters afforded the corresponding free thioglycosides 7a-h. The structures of the reaction products were elucidated based on spectral data and elemental analysis. [ABSTRACT FROM AUTHOR]

DMF has been proved to be an efficient formylation reagent for 2-aminophenols in the presence of (±) camphorsulfonic acid (CSA) in this work. CSA works as an acid catalyst and a neutralizer of dimethyl amine which is kicked off from DMF. Both electron-withdrawing and electron-donating groups are tolerated. More importantly, the product could be achieved in gram scale with the possibility of further diversifying into biologically interesting structures. [ABSTRACT FROM AUTHOR]

An energetic derivative of 2,2′,4,4′,6,6′-hexanitrostilbene (HNS) and 2,4,7,9-tetranitro-10H-benzofuro[3,2-b]indole (TNBFI) has been synthesized from the N,N-dimethylformamide (DMF) solution of HNS with different tertiary amine additives, 4-(4-pyridyl)morpholine and 1,1-bis(morpholino) ethylene. TNBFI crystallized with DMF in a solvate, TNBFI·2DMF, was identified by negative ESI mass spectrum and single-crystal X-ray diffractions. The 3D-supermolecular structure of TNBFI·2DMF was built from the alternate stacking of TNBFI and DMF layers with π-stacking interactions between TNBFI molecules and H-bonding interactions between TNBFI and DMF molecules. The energetic properties of TNBFI molecule as well as the thermal stability of its DMF solvate have been investigated. [ABSTRACT FROM AUTHOR]

Several polymetallic anionic clusters display a strong tendency to form robust ion-pairs with appropriate counter cations. We have isolated decavanadate cluster [H2V10O28]4- with, hitherto unreported, dimethylammonium ions, [N(CH3)2H2]4+ as counter cations from vanadyl sulfate and N,N'-dimethylformamide (DMF). It is proposed, for the first time, that dimethylammonium ions are formed by reduction and simultaneous decarboxylation of DMF with oxidation of vanadyl sulfate occurring concomitantly under specified reaction conditions. The different colors observed during the course of the reaction are monitored by UV-Visible spectrophotometry. The structure of isolated cluster compound with four counter cations is confirmed by single crystal X-ray diffraction techniques. The compound is also tested for its DNA/BSA binding efficacy and cytotoxicity on human epitheloid cervix carcinoma (HeLa) cells along with vanadates—vanadium pentoxide and ammonium metavanadate. Based on the results, the cluster shows better IC50 and binding values than vanadates. [ABSTRACT FROM AUTHOR]

Site-directed delivery of antimicrobial agents for inflammatory diseases showed significant medical advances, which can be realized through drug-loaded electrospun fibers. In this study, paclitaxel was applied as model hydrophobic drug, and the effect of solvent ratio on drug distribution and release kinetics would be discussed. It was found that different co-solvent ratios (9:1, 7:3, and 5:5, v:v) of chloroform and dimethylformamide could alter the resultant fiber diameter and morphology as well as paclitaxel release kinetics. Slower release was observed with higher ratio of chloroform. XPS results showed that this is primarily due to a better dispersion of paclitaxel in the fibers prepared from solvent ratio of 9:1 whereas the drug was found to accumulate on the surface for samples 5:5 and 7:3. Our results provided insight into the importance of solvent and solvent ratio not just in fabrication of required fibrous structure but also on release of active compounds. [ABSTRACT FROM AUTHOR]

Site-directed delivery of antimicrobial agents for inflammatory diseases showed significant medical advances, which can be realized through drug-loaded electrospun fibers. In this study, paclitaxel was applied as model hydrophobic drug, and the effect of solvent ratio on drug distribution and release kinetics would be discussed. It was found that different co-solvent ratios (9:1, 7:3, and 5:5, v:v) of chloroform and dimethylformamide could alter the resultant fiber diameter and morphology as well as paclitaxel release kinetics. Slower release was observed with higher ratio of chloroform. XPS results showed that this is primarily due to a better dispersion of paclitaxel in the fibers prepared from solvent ratio of 9:1 whereas the drug was found to accumulate on the surface for samples 5:5 and 7:3. Our results provided insight into the importance of solvent and solvent ratio not just in fabrication of required fibrous structure but also on release of active compounds. [ABSTRACT FROM AUTHOR]

Temperature-sensitive poly(vinylidene fluoride)-graft-poly(N-isopropylacrylamide)(PVDF-g-PNIPAAm) copolymer was synthesized and its flat membranes were prepared through phase inversion method with mixture of N,N-dimethylformamide (DMF) and tetrahydrofuran (THF) as solvent in water coagulation bath. The effects of “open time” (solvent-evaporation time) on the structure and performance of membranes were investigated by X-ray photoelectron spectroscopy, field-emission scanning electronic microscopy, contact angle, filtration experiments and static protein adsorption. It was found that the increasing “open time” endowed the membrane with more pores on the surface, higher flux and better hydrophilicity, provided the membrane with lower protein adsorption. Thus, the copolymer membranes showed a good antiprotein fouling. [ABSTRACT FROM AUTHOR]

4-(3-(4-Hydroxyphenyl)-1-phenyl-1H-pyrazol-4-yl)-6-phenyl-2-thioxo-1,2-di hydro-pyridine-3-carbonitrile (1) reacted with ethyl chloroacetate (2) in ethanolic sodium acetate solution to yield the corresponding ethyl (3-cyanopyridin-2-ylsulphanyl)acetate derivative 3. Intramolecular cyclization of compound 3 was achieved by its heating in DMF containing potassium carbonate to afford the corresponding ethyl 3-aminothieno[2,3-b]pyridine-2-carboxylate derivative 4 which reacted with hydrazine hydrate in refluxing pyridine to yield the starting material 3-aminothieno[2,3-b]pyridine-2-carbohydrazide derivative 7. Compound 7 reacted with different reagents such as triethylorthoformate, formic acid, acetic acid and acetic anhydride to afford the target molecules pyrido[3′,2′:4,5]thieno[3,2-d]pyrimidin-4(3H)-one derivatives 8-10, 12 and 13 in good to excellent yields. On the other hand, pyridine-2(1H)-thione derivative 1 reacted with hydrazine hydrate in refluxing pyridine to give the other starting material 3-amino-1H-pyrazolo[3,4-b]pyridine derivative 20 which reacted with acetylacetone under reflux to afford the target molecule pyrido[2′,3′:3,4]pyrazolo[1,5-a]-pyrimidine derivative 21 in a good yield. The structures of target molecules were elucidated using elemental analyses and spectral data. [ABSTRACT FROM AUTHOR]

In this article, we have presented a novel and efficient method for the direct synthesis of unsymmetrical sulfides through the copper(I)-catalyzed cross-coupling of 2-nitro benzenesulfonamides with thiols in the presence of catalytic amount of CuI in DMF as solvent at 100 °C. In addition, the products were obtained in high to excellent yields. More importantly, the novel system showed the primary 2-nitro benzenesulfonamides as a new coupling partner and regioselectively promoted C-S bond-forming transformations through the cleavage of Ar-SO2NH2 bonds. [ABSTRACT FROM AUTHOR]

This work deals with fast-dissolving drug delivery systems of meloxicam (MX) derived from electrospun polyvinylpyrrolidone (PVP)/2-hydroxypropyl-β-cyclodextrin (HPβCD) nanofiber mats. Electrospinning of solutions with different solvent systems [dimethylformamide (DMF) and ethyl alcohol (EtOH)] was performed. Prepared films were evaluated for morphology, physical, and mechanical properties. MX content, dissolving time, MX release, and cytotoxicity of films were investigated. In vivo studies were also performed in healthy human volunteers. The results showed that MX/HPβCD complexes improved the solubility of MX. PVP also increased MX solubility and the stability of MX/HPβCD complexes. Films were successfully prepared by two solvent systems with fiber in the nanometer range. MX was well incorporated into the films (100% efficiency). The X-ray patterns and DSC experiment indicated an amorphous form of MX. A fast disintegration time and burst release of MX was obtained from EtOH system. Cytotoxicity testing of the films produced by EtOH system proved safer than the DMF system. In vivo studies revealed that films rapidly dissolved in the mouth and had a less bitter taste than MX. These results suggest that electospun films from EtOH system may be a good candidate for fast-dissolving drug delivery systems to increase palatability of dosage forms. [ABSTRACT FROM AUTHOR]

A series of novel pyrimido[4,5-c]isoquinolines (3a-3h) and 1,2,3-triazole-coupled pyrimido[4,5-c]isoquinolines (4a-4h) were synthesized in good to excellent yields in the one-pot method. The reaction of 6-amino-1,3-dimethyluracil with different 2-iodo benzoyl chlorides using Pd catalyst in dimethylformamide afforded corresponding pyrimido[4,5-c]isoquinolines (3a-3h). One-pot reaction of pyrimido[4,5-c]isoquinolines with propargyl bromide and benzyl azide in THF at room temperature furnished 1,2,3-triazole-coupled pyrimido[4,5-c]isoquinoline (4a-4h). In vitro antioxidant activity examination revealed that compounds 4d and 4c found to exhibit potent antioxidant activity as compared to the standard drug Trolox with IC50 values 6.02 ± 0.6 and 12.18 ± 0.9 µM, respectively. [ABSTRACT FROM AUTHOR]

A simple and efficient method of catalyst free for the sp3 C-H bond activation of methyl aza-arene and nucleophilic addition to tryptanthrins in DMF was developed. Importantly, the more efficient and green isolation strategy of the purification of the products by centrifugation with 90% yields was applied. [ABSTRACT FROM AUTHOR]

Pd-doped methyl-modified SiO2 membrane materials were prepared by sol-gel technique with tetraethylorthosilicate (TEOS) and methyltriethoxysilane (MTES) as silicon precursors, PdCl2 as palladium source. N, N-dimethylformamide (DMF) was used as a drying control chemical additive (DCCA). The samples were characterized by X-ray Diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and thermogravimetric (TG)-differential thermogravimetric (DTG) measurement. The effect of DMF addition on the phase and chemical structures of Pd-doped SiO2 membrane materials calcined at 350°C was discussed. The results showed that the diffraction peaks of metallic Pd0 and PdO appeared in the XRD curve of Pd-doped SiO2 membrane material without DMF, while only the metallic Pd0 diffraction peak can be explicitly observed in the Pd-doped SiO2 membrane material with DMF. DMF has no significant influence on the chemical structure of Pd-doped SiO2 membrane materials but can delay the oxidation of metallic Pd0 to PdO in the air. [ABSTRACT FROM AUTHOR]

N,N-Dimethylformamide (DMF)-based ionic liquid is a multipurpose ionic liquid having numerous applications. In the present study it has been shown to be an efficient and recyclable nucleophilic reagent-cum-solvent for the synthesis of a variety of 1,2-disubstituted-3,4-dihydronaphthalenes by cycloaddition of different vinylarenes with electron-deficient alkynes. The present protocol has been demonstrated to be more efficient, green and cost effective as compared with other reported methods. [ABSTRACT FROM PUBLISHER]

A series of alternating polyfluorene copolymers containing fluorene (P1-OF), bithiophene (P2-BT), and thiophene (P3-TH) moieties have been synthesized via a palladium-catalyzed Suzuki coupling reaction. Among them, theP3-THpolymer highly contains hydroxyl groups which provides enough solubility in polar solvents such as alcohols and dimethylformamide. Multilayer polymer light-emitting diodes have been fabricated using a semiconducting polymer, F8BT, as an emissive layer and the methanol-solubleP3-THas an electron-transport layer. By the device configuration of ITO/PEDOT/TFB/F8BT/P3-TH/LiF/Al, it shows a luminescence efficiency of 1.48 cd/A and a turn-on voltage of 4.6 V. The emission with maxima at 448 nm and 495 nm which fell in the blue region with the CIE coordinates (x = 0.18, y = 0.24). [ABSTRACT FROM PUBLISHER]

A highly selective two-component silica gel-promoted synthesis of 1,3-oxathiolan-5-one derivatives in N,N-Dimethylformamide (DMF) is presented. The reaction was carried out using aromatic aldehyde and mercaptoacetic acid in the presence of silica gel in DMF with heating. The reactions were worked up by separating the silica gel and recovering the solid product after adding water in excellent yields without any chromatographic purification. Structures of the compounds were satisfactorily confirmed by1H NMR and LCMS spectral analysis. [ABSTRACT FROM PUBLISHER]

The new thiohexanoic acid substituted zinc phthalocyanine was synthesized and characterized by FT-IR, 1H–NMR, electronic spectroscopy, and mass spectrometry as well as DFT calculation studies. The photochemical properties (singlet-oxygen quantum yields and photodegradation quantum yields) and photophysical properties (fluorescence quantum yields and fluorescence behavior) of the compound were studied in dimethylsulfoxide (DMSO), dimethylformamide (DMF) and tetrahydrofuran (THF). Singlet-oxygen quantum yields ranged from 0.29 to 0.43. However, energy-minimized structure, vibrational frequency, electronic distribution and molecular orbitals were obtained by DFT calculations which were supported by experimental results. [ABSTRACT FROM AUTHOR]

The electrospinning of poly(vinyl alcohol) (PVA) (99% hydrolysis degree) aqueous solution with added organic solvents N, N-dimethylacetamide (DMAc) or N, N-Dimethylformamide (DMF) was investigated. After the addition of the organic solvents to the PVA aqueous solutions, the surface tension and conductivity decreased and the viscosity significantly increased, which caused an improved electrospinnability of the PVA solutions. The micro-structures of the three solutions were investigated by dynamic light scattering (DLS), differential scanning calorimetry (DSC) and dynamic viscoelastic measurements. The DLS data revealed that the swelling of the PVA coils was slightly increased but the overlaps of PVA coils decreased greatly after one of the organic solvents was added to the aqueous solution. The DSC data showed both the water-rich phase and PVA-rich phase were destroyed and the solution became more homogenous after the addition due to the interaction between the organic solvent and water. Viscoelastic data showed there was an obvious difference in the storage modulus behavior between the aqueous solutions and the water/solvents solutions. These changes in the micro-structure and properties were the reason for the improved electrospinnability of the PVA solution. According to scanning electron microscopy (SEM), the average diameter of the electrospun PVA nanofibers was about 308 nm for the DMF/water system, and 255 nm for the DMAC/water system, as compared with uneven diameter nanofibers for the water system. [ABSTRACT FROM AUTHOR]

Phosphorous-based organic acids (P) and diamine (M) were used to produce a supramolecular PM complex at a 2:1 molar ratio, which then formed a stable gel in dimethyl sulfoxide (DMSO) and N, N-dimethylformamide (DMF). According to SEM, the morphologies of the aggregates depended on the steric substitute of phosphorous-based organic acids and the structure of the complementary diamine.31P NMR and FTIR spectroscopies revealed that hydrogen bonding within the PM complex was the main driving force for the self-aggregation. XRD studies revealed that the two-component gelators mainly assemble into a stricter lamellar structure when increasing the rigidity of the complementary component. In contrast, the gelators with the aliphatic unit mainly assembled into a random lamellar structure and showed more possibility of deforming. As such, the results in this paper demonstrate how structure effects in two-component gel system of phosphorous-based organic acids and diamine can control self-assembly process. [ABSTRACT FROM AUTHOR]

Two lanthanide (Sm and La) complexes with the Schiff base ligand bis(3-methoxysalicylidene)-3-oxapentane-1,5-diamine (Bod) have been synthesized and characterized by physico-chemical and spectroscopic methods. [Sm(Bod)(NO3)3] {bis(3-methoxysalicylidene)-3-oxapentane-1,5-diamine samarium(III) trinitrate} (1) is a discrete mononuclear species and [La(Bod)(NO3)3(DMF)]n {bis(3-methoxysalicylidene)-3-oxapentane-1,5-diamine dimethylformamide lanthanum(III) trinitrate}n (2) formed an inorganic coordination polymer. In the two complexes, the metal ions are both ten-coordinate and the geometric structure around the Ln(III) ions can be described as distorted hexadecahedral. An antioxidant assay in vitro shows that complexes 1 and 2 exhibit better scavenging activity than both the ligand and the usual antioxidants on hydroxyl and superoxide radicals. Under excitation at room temperature, a red shift in the fluorescence band of the ligand in the complexes compared with that of the free ligand can be attributed to coordination of the rare earth ions to the ligand. Furthermore, 1 produced characteristic Sm(III) luminescence, which indicates the ligand Bod is a good organic chelator to absorb energy and transfer it to the Sm3+ ion. [ABSTRACT FROM AUTHOR]