Synthesis and properties of a novel squaraine dye modified by ferrocene

A novel squaraine dye（SQ） modified by ferrocene has been synthesized through（E）-dodecyl-2-ferrocenyl vinyl-1H-pyrrole and squaric acid.The molecular structure of SQ was characterized by ¹H NMR,¹³C NMR,MS and elemental analysis.SQ is high soluble in common solvents.The maximum absorptions of SQ in different solvents are in the range of 708-734 nm,exhibiting positive solvatochromism with increasing solvent polarity.The optical and electrical properties of SQ indicate that it is a promising electron donor material for bulk-heterojunction organic solar cell.     

Synthesis and dyeing performance of a novel polycarboxylic acid azo dye

A novel reactive polycarboxylic acid dye was synthesized by the reaction of polymaleic anhydride（PMA） with 3-methyl-1-（4- sulfonylphenyl）-4-（4-aminophenylazo）-2-pyrazoline-5-one.The structure of the novel dye was characterized by FTIR,UV-vis and ¹³C NMR spectra.The dyeing properties of dye on cotton were tested,and the novel dye possessed high fixation and good fastness.     

Synthesis and post-synthetic derivatization of a cyanine-based amino acid. Application to the preparation of a novel water-soluble NIR dye

An efficient synthesis of a new fluorescent amino acid derived from a pentamethylene cyanine dye is described. Selective derivatization of its amino group with an original trisulfonated linker has led to a novel water-soluble NIR dye suitable for covalent labeling of biomolecules     

Synthesis and properties of a novel hyperbranched polyphosphate acrylate applied to UV curable flame retardant coatings

A series of hyperbranched polyphosphate acrylates (HPPAs) being used for UV curable flame retardant coatings were prepared by the reaction of tri(acryloyloxyethyl) phosphate (TAEP) with piperazine at given ratios, and characterized using FTIR, ¹H NMR and GPC measurements. HPPA was blended with TAEP in different ratios to obtain a series of UV curable resins. Their maximum photopolymerization rates and final unsaturation conversion (P^f) in the cured films at the presence of a photofragmenting initiator were investigated. The results showed that the P^f increased along with HPPA content and the pure HPPA has the maximum value of 82.1% in the photo-DSC analysis. The data from dynamic mechanical thermal analysis showed that HPPA has good miscibility with TAEP. The crosslinking density and T_g of the cured film decrease along with the content of HPPA in the blend. The mechanical properties of the cured films were also investigated. Less than 20% HPPA addition improved both the tensile strength and elongation at break without damaging the modulus. The HPPA₂₀TAEP₈₀ film with 20% HPPA addition has the highest tensile strength of 31.7 MPa and an elongation at break two times that of cured TAEP. The flame retardancy of the UV cured films was investigated by the limiting oxygen index (LOI). The cured TAEP/HPPA samples greatly expanded when burning, and the degree of expansion increased along with HPPA content. However, the LOI values decreased from 47.0 to 34.0 along with HPPA content, which can be ascribed to that the flame retardancy of TAEP is mainly acting in the gas phase, whereas HPPA mainly acting in condensed phase, and the gas phase mechanism holds the dominant effect while their blends are burning.     

Synthesis,spectroscopic properties and applications of novel N-heterocycle-containing benzotriazoles as UV absorbers

Two novel iV-heterocycle-containing benzotriazole compounds,5-(5-chloro-2-benzotriazolyl)-6-hydroxy-l,4-dimethyl-3-car-bonitrile -2-pyridone(2) and 4-(5-chloro-2-benzotriazoIyl)-5-methyl-2-phenyl-3-pyrazolone(4),were synthesized from reactant 4- chloro-2-nitroaniline via diazotization,azo coupling,reductive cyclization and acidification.Their structures were confirmed by FT-IR,~1H NMR,mass spectroscopy and elemental analysis.Their spectral properties were investigated and compared with that of a common commercial benzotriazole UV absorber Tinuvin 326.It is found that the novel Af-heterocycle-containing benzotriazole compounds exhibit sharp single peak in the range of 280-400 nm and have much higher molar extinction coefficients than that of Tinuvin 326.Their anti-UV protection properties on polyester fabric were also evaluated and compound 4 was much superior to compound 2 due to its higher exhaustion.     

A novel application of nylon membranes to the luminescent determination of benzo[a]pyrene at ultra trace levels in water samples

Very simple and highly sensitive methods are presented for the determination of benzo[a]pyrene, one of the most carcinogenic polycyclic aromatic hydrocarbons (PAHs). The approaches are based on solid-phase extraction of the analyte on a nylon membrane via a syringe procedure, and its fluorescent or phosphorescent determination on the solid surface. While the native fluorescence of benzo[a]pyrene retained on a nylon surface is measured directly, room-temperature phosphorescence is induced by spotting a few microlitres of thallium(I) nitrate solution on the surface (heavy-atom effect). An enhancement of the phosphorescence signal was corroborated when the measurements were carried under a nitrogen atmosphere. The analytical figures of merit obtained under the best experimental conditions demonstrate the capability of detecting benzo[a]pyrene at a sub-parts-per-trillion (sub-ng L⁻¹) level. The potential interference from other common PAHs and also from different metal ions was studied. The feasibility of determining benzo[a]pyrene in real samples was successfully evaluated through the analysis of spiked tap, underground and mineral water samples of different origins. Recoveries obtained from spiked river waters were successfully compared with those provided by a reference method, through rigorous statistical analysis.     

Synthesis and study of a novel hybrid UV photoinitiator: p-benzoyldiphenyliodonium hexafluorophosphate (PhCOPhI+PhPF)

A novel hybrid photoinitiator, p-benzoyldiphenyliodonium hexafluorophosphate (PhCOPhI⁺PhPF⁻₆), was synthesized, characterized, and studied. It absorbs UV light not only below 300 nm, but above 300 nm as well. When exposed to UV light, it undergoes an asymmetrical photocleavage to produce cation-radicals and radicals which could induce cationic and radical polymerizations respectively. Compared with the simple iodonium salt PhI⁺PhPF⁻₆, and bimolecular sensitization system PhCOPh/PhI⁺PhPF⁻₆, the covalently bonded photosensitization system PhCOPhI⁺PhPF⁻₆ is much more efficient as a photoinitiator. Oxygen has a small negative effect on the cationic polymerization photoinitiated by PhCOPhI⁺PhPF⁻₆, while isopropanol has a small positive influence only in argon atmosphere. © 1996 John Wiley & Sons, Inc.     

Synthesis and characterization of monodisperse, mesoporous, and magnetic sub-micron particles doped with a near-infrared fluorescent dye

Recently, multifunctional silica nanoparticles have been investigated extensively for their potential use in biomedical applications. We have prepared sub-micron monodisperse and stable multifunctional mesoporous silica particles with a high level of magnetization and fluorescence in the near infrared region using an one-pot synthesis technique. Commercial magnetite nanocrystals and a conjugated-NIR-dye were incorporated inside the particles during the silica condensation reaction. The particles were then coated with polyethyleneglycol to stop aggregation. X-ray diffraction, N₂ adsorption analysis, TEM, fluorescence and absorbance measurements were used to structurally characterize the particles. These mesoporous silica spheres have a large surface area (1978 m²/g) with 3.40 nm pore diameter and a high fluorescence in the near infrared region at λ=700 nm. To explore the potential of these particles for drug delivery applications, the pore accessibility to hydrophobic drugs was simulated by successfully trapping a hydrophobic ruthenium dye complex inside the particle with an estimated concentration of 3 wt%. Fluorescence imaging confirmed the presence of both NIR dye and the post-grafted ruthenium dye complex inside the particles. These particles moved at approximately 150 μm/s under the influence of a magnetic field, hence demonstrating the multifunctionality and potential for biomedical applications in targeting and imaging.     

Brompheniramine as a novel probe for indirect UV detection and its application for the capillary electrophoresis of adamantane drugs

Brompheniramine, an antihistamine drug, was employed as a novel UV probe for capillary electrophoresis with indirect UV detection of adamantane drugs (memantine, amantadine, and rimantadine). The probe possesses high molar absorptivity of 24 × 10³ L/mol cm at 6 mM, which enables the measurement of these nonchromophore analytes without derivatization. The simple background electrolyte (10 mM sodium dihydrogen phosphate (pH 5.0) containing 5 mM brompheniramine and 6 mM β‐cyclodextrin) provided the separation of the analytes in a short time (7.5 min). Under these conditions, brompheniramine had similar mobility to that of the analyte ions resulting in symmetric peaks with minimal electrodispersion. The analytes displace the probe at a one‐to‐one ratio with transfer values close to unity. β‐Cyclodextrin played a role in the resolution of the structurally similar adamantane derivatives. Method validation showed good linearity (r ² > 0.98), precision (%RSD ≤ 3.30), and accuracy (recoveries ranging from 98 to 109%). The proposed method was successfully applied to determine the adamantane content in pharmaceutical products.     

Synthesis of reactive copolyesters derived from isophthaloyl chloride,bisphenol a,and aliphatic diols with additional reactive groups

Copolycondensation of isophthaloyl chloride, bisphenol A, and aliphatic diols with additional reactive groups were performed in the presence of triethylamine by a trimethyl phosphate/cyclohexane organic/organic interfacial method. The composition of idol and bisphenol A residues in the resulting copolyesters is very close to that in the feed from the initial stage of reaction. The resulting copolyesters with reactive groups can be used for the preparation of various functional polymers. The mechanism of an organic/organic interfacial polycondensation was also discussed. © 1995 John Wiley & Sons, Inc.     

Synthesis,structural characterization and molecular modelling of bidentate azo dye metal complexes: DNA interaction to antimicrobial and anticancer activities

A novel azo dye ligand, namely 1‐[(5‐mercapto‐1H‐1,2,4‐triazole‐3‐yl)diazenyl]naphthalen‐2‐ol (HL), was synthesized. Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺ and UO₂²⁺ complexes were also prepared by the treatment of HL with Mn(CH₃COO)₂?4H₂O, Co(CH₃COO)₂?4H₂O, Ni(CH₃COO)₂?4H₂O, Cu(CH₃COO)₂?H₂O, CuCl₂?2H₂O, Cu(NO₃)₂?6H₂O and UO₂(NO₃)₂?6H₂O. The structures of these metal chelates were confirmed using elemental, spectral, magnetic moment, molar conductance and thermal analyses. The analytical data confirmed the formation of the chelates in 1:1 (metal‐to‐ligand) ratio having the formula [ML(H₂O)X]Y?H₂O, where M is Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺ or UO₂²⁺; X is Cl^?, NO₃^? or CH₃COO^?; and Y is H₂O. The azo compound acts in a monobasic bidentate manner via the nitrogen and oxygen atoms of azo and hydroxyl groups, respectively. All complexes were found to have tetrahedral structures, except the UO₂²⁺ complex that showed octahedral geometry. The mode of interaction between the synthesized complexes and calf thymus DNA was explored by the aid of absorption spectroscopy and viscosity measurements. The azo dye and its chelates were evaluated against the growth of various bacterial and fungal strains (Escherichia coli, Staphylococcus aureus, Aspergillus flavus and Candida albicans) with insight gained into the effect of type of metal centre, type of coordinated anion and position of the metal in the periodic table on the activity of the complexes. The geometric structure of the complexes was optimized using molecular modelling. The in vitro cytotoxicity of the synthesized compounds was tested against HEPG2 cell line.     

Development of a HPLC method for determination of four UV filters in sunscreen and its application to skin penetration studies

This study describes the development, validation and application of a high‐performance liquid chromatography (HPLC) method for the simultaneous determination of the in vitro skin penetration profile of four UV filters on porcine skin. Experiments were carried out on a gel‐cream formulation containing the following UV filters: diethylamino hydroxybenzoyl hexyl benzoate (DHHB), bis‐ ethylhexyloxyphenol methoxyphenyl triazine (BEMT), methylene bis‐ benzotriazolyl tetramethylbutylphenol (MBBT) and ethylhexyl triazone (EHT). The HPLC method demonstrated suitable selectivity, linearity (10.0–50.0 μg/mL), precision, accuracy and recovery from porcine skin and sunscreen formulation. The in vitro skin penetration profile was evaluated using Franz vertical diffusion cells for 24 h after application on porcine ear skin. None of the UV filters penetrated the porcine skin. Most of them stayed on the skin surface (>90%) and only BEMT, EHT and DHHB reached the dermis plus epidermis layer. These results are in agreement with previous results in the literature. Therefore, the analytical method was useful to evaluate the in vitro skin penetration of the UV filters and may help the development of safer and effective sunscreen products.     

Synthesis,characterization and in vitro antimicrobial and anti‐breast cancer activity studies of metal complexes of novel pentadentate azo dye ligand

A new azo dye with N3O2 donor set of atoms has been synthesized via coupling reaction of 2,6‐diaminopyridine with p‐methoxybenzaldehyde. The molecular and electronic structure of the azo dye ligand (L) was optimized theoretically and the quantum chemical parameters were calculated. Molecular docking was used to predict the binding between L and the receptors of breast cancer mutant 3hb5‐oxidoreductase, crystal structure of Escherichia coli (3 T88) and crystal structure of Staphylococcus aureus (3q8u). The newly synthesized L was used for complex formation with Cr(III), Mn(II), Fe(III), Co.(II), Ni(II), Cu(II), Zn(II) and Cd(II) ions. The nature of bonding and the stoichiometry of L and its mononuclear complexes were deduced from elemental analyses, spectroscopic, magnetic susceptibility, molar conductance, electron spin resonance and conductivity measurements, thermogravimetric analyses and powder X‐ray diffraction. Elemental analysis data show that the complexes have composition of ML type with an octahedral geometry for all the complexes. The activation thermodynamic parameters were calculated. The prepared azo dye and its metal complexes were tested against various Gram‐positive and Gram‐negative bacteria and a fungus. Most complexes exhibit antibacterial and antifungal activities against these organisms. Anticancer evaluation studies against standard breast cancer cell line were performed using various concentrations. The activity index was calculated. Copyright © 2016 John Wiley & Sons, Ltd.     

CoCr2O4@GeO2@ZnO core-shell nanoparticle as a novel recoverable catalyst: Preparation,characterization and photocatalytic degradation of basic fuchsin dye

Highly photosensitive novel nanostructure CoCr₂O₄@GeO₂@ZnO core-shell UV–Visible light driven photocatalyst have been fabricated by sol-gel method. The double coating of GeO₂ and ZnO on CoCr₂O₄ nanoparticles could intensely stabilize the CoCr₂O₄ in aqueous solution and avoid their oxidation. The synthesized CoCr₂O₄, CoCr₂O₄@GeO₂, and CoCr₂O₄@GeO₂@ZnO nanostructures were characterized by several techniques including FT-IR, XRD, UV-DRS FE-SEM, EDS, HR-TEM and BET analysis. The potential application of CoCr₂O₄@GeO₂@ZnO is examined for photocatalytic degradation of Basic Fuchsin dye in aqueous heterogeneous suspension. The detailed degradation pathway has been established by using LC-MS analysis and by a careful identification of intermediate products. The result suggest that CoCr₂O₄@GeO₂@ZnO photocatalysis may be envisaged as a method for treatment of diluted waste water in textile industries. In the present study, the degradation yield for Basic Fuchsin dye 100% within 30 ​min using core-shell CoCr₂O₄@GeO₂@ZnO nanostructure material.     

Synthesis,properties and application of novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF2) fluorescent dyes: BOPYPYs

Novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF₂) fluorescent dyes (BOPYPYs) were synthesized by reaction of pyrrole-2-carboxaldehyde with 1-(pyrazin-2-yl) hydrazine in the presence of Et₃N-BF₃·Et₂O for the first time.     

Synthesis, characterization, and DFT studies of a novel azo dye derived from racemic or optically active binaphthol

We present a new azo reactive dye from racemic or optically active BINOL. This dye was characterized by UV-vis, FTIR, mass, ¹H NMR, and ¹³C NMR spectroscopic techniques and elemental analysis. The structure and spectrometry of this azo dye have been investigated theoretically by performing HF and DFT levels of theory using the standard 6-31G^∗ basis set. The optimized geometries and calculated vibrational frequencies are evaluated via comparison with experimental values. The vibrational spectral data obtained from solid phase FTIR spectra are assigned based on the results of the theoretical calculations. The theoretical electronic absorption spectra have been calculated using CIS, TD-DFT, and ZINDO methods. In addition, a good agreement between calculated and experimental NMR data is observed.     

Synthesis,properties and application of novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF2) fluorescent dyes: BOPYPYs

Novel 5,6,5,6-tetracyclic pyrazine/pyrrole-fused unsymmetric bis(BF₂) fluorescent dyes (BOPYPYs) were obtained by reaction of pyrrole-2-carboxaldehyde with 1-(pyrazin-2-yl)hydrazine in the presence of Et₃N-BF₃·Et₂O for the first time. The absorption maxima of pyrazine-fused BOPYPY are obviously bathochromic shifts, in contrast to those of the reported BOPPY, indicating that the discrepant substitute groups between pyridine and pyrazine result in the remarkable wavelength difference. The new series of BOPYPYs possess high molar extinction coefficients, high fluorescence quantum yields, and larger Stokes shifts. A Knoevenagel reaction of BOPYPY with 4-dimethylaminobenzaldehyde smoothly produced the dye with the extension of π-conjugation. Dimethylamino-containing BOPYPY as a pH-responsive fluorescent sensor could detect pH value.     

A simple and sensitive HPLC‐UV determination of 7‐O‐succinyl macrolactin A in rat plasma and urine and its application to a pharmacokinetic study

A simple, sensitive and reproducible isocratic reversed‐phase (C₁₈) high‐performance liquid chromatography (HPLC) method was developed to determine 7‐O‐succinyl macrolactin A (SMA) in rat plasma and urine samples using UV detector set at 230 nm. Lamotrigine was used as internal standards (IS) to ensure the precision and accuracy of the method. The retention times of SMA and IS for the plasma sample were 9.2 and 4.4 min, respectively, and those for the urine samples were 7.9 and 4.3 min, respectively. The intra‐ and inter‐day variations of the analytical responses, expressed in terms of relative standard deviation, were less than 14.9%. The accuracy, in terms of average analytical recovery, ranged from 90.4 to 119%. The lower limits of quantification of SMA in rat plasma and urine samples were 0.02 and 0.1 µg/mL, respectively. This method is applicable for the pharmacokinetic studies of SMA in rats. Copyright © 2012 John Wiley & Sons, Ltd.     

Comparison of LC‐UV and LC–MS methods for simultaneous determination of teriflunomide,dimethyl fumarate and fampridine in human plasma: application to rat pharmacokinetic study

This study describes a comparison between LC‐UV and LC–MS method for the simultaneous analyses of a few disease‐modifying agents of multiple sclerosis. Quantitative determination of fampridine (FAM), teriflunomide (TFM) and dimethyl fumarate (DMF) was performed in human plasma with the recovery values in the range of 85–115%. A reversed‐phase high‐performance liquid chromatography (HPLC) with UV as well as MS detection is used. The method utilizes an XBridge C₁₈ silica column and a gradient elution with mobile phase consisting of ammonium formate and acetonitrile at a flow rate of 0.5 mL min^?1. The method adequately resolves FAM, TFM and DMF within a run time of 15 min. Owing to low molecular weights, the estimation of DMF and FAM is more versatile in UV than MS detection. With LC‐UV, the detection limits of FAM, TFM and DMF were 0.1, 0.05, 0.05 μg and the quantification limit for all the analytes was 1 μg. With LC–MS, the detection and quantification limits for all of the analytes were 1 and 5 ng, respectively. The two techniques were completely validated and shown to be reproducible and sensitive. They were applied to a pharmacokinetic study in rats by a single oral dose. Copyright © 2016 John Wiley & Sons, Ltd.