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This study includes the preparation of some new compounds for Schiff bases [H1-H5] through the reaction of the compound 4,4-azodibenzaldehyde with aromatic amine substitutes with absolute ethanol, then converting Schiff bases to derivatives of 1,3-oxazepin 4,7-dione [H6-H10] Correspondence through its reaction with maleic anhydride compound in dry benzene. The prepared compounds were characterized by spectroscopic methods from the UV-Vis spectrum, infrared (FT-IR) and 1H-NMR proton nuclear magnetic resonance spectra, in addition to determining the melting points and purity of the prepared compounds, and following up the course of the reactions by TLC thin layer chromatography. The antibacterial activity of some prepared compounds was also evaluated on two types of Gram-positive Staphylococcus aureus (Gr+ve) and Gram-negative Pseudomonas aeruginosa (Gr-ve). [ABSTRACT FROM AUTHOR]

Treatment of thiosemicarbazide with carbon disulfide under reflux in alcoholic sodium carbonate solution afforded 2-amino-5-mercapto-1,3,4-thiadiazole [I]. Coupling reaction was carried out between the diazonium salt of compound [I] and basic solution of 2-hydroxybenzaldehyde giving azo compound [II]. Microwave irradiation technique was used to perform the condensation of aldehyde function in compound [II] with some selected aromatic amines in ethyl alcohol to produce Schiff bases [III]a−g. Microwave irradiation of imines [III]a-g and α-chloroacetyl chloride in dimethylformamide gives azetidin-2-ones [IV]a-g in high yield (65–97%). The target compounds were screened for their antibacterial actions against Staphylococcus aurous (Gram-positive) and Escherichia coli (Gram-negative). The results of the study showed that the azetidine-2-one compounds [IV]c, [IV]d, [IV]e and [IV]f demonstrated larger activities against both kinds of bacteria in comparison with that of the control drug (amoxicillin-clavulanate). [ABSTRACT FROM AUTHOR]

N-methylated diaminotriphenylmethane dye or MG, is mainly utilized in aquaculture as a remedial agent. The occurrence of dye can be seen in a solution in combination of its carbinol base and cation (chromatic malachite green), along with the varying ratio according to the pH of the solution; the dye can also be reduced chemically and metabolically to leuco derivative. Following exposure to MG, analysis of fish tissue reveals the existence of both leuco and chromatic forms, with end it has a much longer tissue half-life. The leuco derivative of malachite green has a morphological similitude to carcinogenic aromatic amines which leads to formation of covalent DNA adducts, and it fits in with DNA with a preference for A:T-rich regions. In presence of an exogenous metabolising mechanism, MG is mutagenic in Salmonella typhimurium TA98. It has the ability to lipid peroxidation in mammalian cells and cause cell transformation and a high level of cytotoxicity. This review concludes, a thorough examination of MG and its physical and chemical characteristics in relation to fisheries. A lot myths and misunderstandings regarding MG are addressed. Its system of operation, toxicity and destiny are all taken into account. [ABSTRACT FROM AUTHOR]

Laccases are multicopper-containing oxidases that can catalyze the oxidation of a wide variety of phenolic compounds, benzenethiols, diamines, and aromatic amines without requiring hydrogen peroxide. Several fungal laccases can degrade synthetic dyes, and therefore are important for the bioremediation of dye-containing waste. Methyl Blue (MB), also known as Cotton Blue and Acid Blue 93, is a widely used textile dye in the denim and other textile industries. MB is an acidic dye that is hard to degrade naturally, and if untreated, can pollute the environment, causing high chemical oxygen demand (COD). It is also toxic if ingested by mammals and fish in large quantities. Therefore, it is important to remove MB from textile waste effluents before releasing the effluents into the environment. This research aims to determine the kinetics of the enzymatic degradation of MB by Trichoderma asperellum LBKURCC1crude laccase extracts at room temperature (±30 °C), without the addition of any mediator molecules. MB solutions with concentrations of 25 ppm and 50 ppm were incubated in the dark with crude extracts of the laccase enzyme (activity 0.007 U/mL or 0.014 U/mL). The absorbance of the colored solution was measured at 594 nm at various time points. Preliminary results show that MB degradation by the laccase crude extracts follows Michaelis-Menten kinetics. A two-fold increase in the MB concentration increased its degradation rate by T. asperellum LBKURCC1 laccase. Likewise, increasing the enzyme activity also increased the degradation rate of MB by the laccase. A buffer control (pH 5.5) of 50 ppm MB solution without adding enzyme showed no decrease in color after four days incubation at room temperature (±30 °C). After four days of incubation at room temperature, the addition of 0.014 U/mL laccase activity could decrease 69% of the 50 ppm MB solution color. However, a heat-denatured laccase solution could decrease 39% of the same MB solution color, showing that the crude enzyme may contain non-enzymatic components that can also contribute to the degradation of MB. [ABSTRACT FROM AUTHOR]

Isatin is a special heterocyclic compound because of its various biological activities. This research aims to synthesize isatin derivatives catalyzed by iron (III) trifluoromethanesulfonate, Fe(OTf)3. In this study, Fe(OTf)3 catalysts were synthesized using Fe3+ ions and Lewis acid and characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray Diffraction (XRD), and Transmission ElectronMicroscope (TEM). The characterization results showed that the catalyst Fe(OTf)3 was successfully formed. Furthermore, Fe(OTf)3 catalysts were applied in the synthesis of isatin derivatives. Schiff base of isatin is a group of organic compounds with azomethine groups that play an essential role in biological systems and act as ligands in developing new chemical entities. The Schiff base of isatin is the product of condensation between the carbonyl compounds of isatin with different aromatic primary amines. In this paper, the synthesis of several Schiff bases of isatin derivatives applies conventional heating methods. The results were described by physicochemical analysis and characterized using UV-Vis spectrophotometry, FT-IR, and LC-MS. The characterization results support the successful synthesis of the isatin compound derivative. [ABSTRACT FROM AUTHOR]

Rice husk and polystyrene waste were combined to obtain bio-oil through pyrolysis process. The bio-oil produced from mixtures of rice husk and polystyrene waste also potential to be used as fuel. The parameters were used for this study are ratios of mixture, temperature, particle sizes and holding time. High yield of bio-oil was obtained on a rice husk/polystyrene waste of 70:30, temperature of 450°C, particle size of 300 µm and holding time of 2 minutes. Results of bio-oil characterization from combination between rice husk and polystyrene proved that the hydrocarbons become increased and the content of acid was decreased. The bio-oil majority consisted of aliphatic and aromatic amines. [ABSTRACT FROM AUTHOR]

We herein report the synthesis of a series of novel pharmacologically relevant coumarins linked with amides. The three-step methodology was found to be facile and compatible with a range of aryl and heteroaryl amines leading to the diverse arena of amides of considerable pharmacological relevance. [ABSTRACT FROM AUTHOR]

In the present work, we report the structural analogs of the antiviral drug Triazavirin. We carry out a study of nucleophilic substitution reaction of the nitro group in azolo[5,1-c][1,2,4]triazines with various aromatic amines and a hydrazine derivative. [ABSTRACT FROM AUTHOR]

A very mild and simple technique for the reduction of aromatic nitro compounds to amines has been developed using BF3.OEt2 Lewis acid and NaOH as a base in ethanol medium at 80 °C temperature. The number of aromatic nitro compounds containing various functional groups was reduced to corresponding aromatic amines in good to excellent yields. [ABSTRACT FROM AUTHOR]

There is commercial interest in understanding the deactivation of Mo loaded H-ZSM-5 catalyst by coke fouling during the methane dehydroaromatization reaction (MDA). The effect of coke on methane diffusion inside the zeolite pores was studied by quasielastic neutron scattering (QENS) measurements on Mo/H-ZSM-5 samples reacted with methane for 0, 7, 25 and 60 min. Catalytic activity of the samples followed by mass spectrometry indicate that the induction period in which Mo species are carburized lasts for ~9 min; after this period the material shows selectivity to aromatics. Characterization by TGA and N2 physisorption suggest that practically no carbon is deposited during the induction period. The ~2 wt % of coke formed after one hour of reaction has a negligible effect in the zeolite crystal structurebut a small effect on the micropore volume. The QENS studies show that the methane transport by jump diffusion is however not measurably affected by the accumulated coke in the samples. [ABSTRACT FROM AUTHOR]

Cancer and microbes today remains one of the most deadly diseases in the world. In search of novel anticancer and antimicrobial probes, a series of newly hybrid molecules synthesized by combining the structural features of aromatic amines and barbituric acid, using the concept of green chemistry. This approach was accomplished efficiently using the aqueous medium to give the corresponding products in a high yield. The newly synthesized compounds were characterized by spectral analysis FT-IR, ¹H NMR, 13C-NMR, HMBC, MASS and Elemental Analysis. Evaluations of these molecules have been carried out using four human cancer cell lines against Doxorubicin as a standard drug. Moreover all the synthesized barbiturates probes were evaluated for their antimicrobial activity against five bacterial strains and four fungal strains. Taken together, this study has led to the development of a convenient, a highly yielded and an environmentally friendly synthetic method of highly promising leads for anticancer and antimicrobial compounds. [ABSTRACT FROM AUTHOR]

Improper discharge of colored effluents in aqueous ecosystems depicts acute toxic effects on aquatic flora and fauna and causing severe environmental problems worldwide. The present study concentrates on efficiency and potentiality of novel strain SBU7 capable of degrading the azo textile dye Mordant Black 17, which was isolated from effluent disposal sites of textile industries, Tirupur. Phenotypic characterization and phylogenetic analysis of the 16S rRNA sequence indicated that the bacterial strain-SBU7 belonged to Pseudomonas aeruginosa. The strain was able to decolorize the azo dye (Mordant Black 17) efficiently up to 86% and 75% in shake and static conditions respectively, in a range of 100 mg L−1, at temperature of 37 □C, at pH 7.0. The spectrophotometric analysis of n-butanol cell extract authenticated the decolorization of dye was obtained because of the degradation of aromatic amines rather the inactive surface adsorption which is further substantiated with TLC and FTIR. [ABSTRACT FROM PUBLISHER]

Self-assembled poly(o-toluidine) (POT) and poly(o-anisidine) (POA) hollow spheres were prepared by oxidative polymerization using ammonium persulfate as the oxidant in the presence of 5% by weight of a polymeric acid, poly(methyl vinyl ether-alt-maleic acid) (PMVEA). The substituent at the ortho position had a significant effect on the size of the hollow nanospheres as determined by SEM and TEM. The nanospheres were of a very uniform size in the presence of the polymeric acid, with average diameters of 338±25 nm for POT and 210±20 nm for POA. The POT and POA hollow spheres were also characterized by FTIR and UV-Vis spectroscopy, which confirmed the chemical identity of the substituted polyanilines. [ABSTRACT FROM AUTHOR]

Polyaniline doped with different protonic acids were chemically synthesized using ammonium persulfate (APS) as an oxidant. These samples were characterized through X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy, which confirms the amorphous nature and acid doping, respectively. Electrical conduction in these samples has been studied through the measurement of I-V characteristics at room temperature as well as in the temperature range from 313 K to 413 K. So obtained characteristic curves were found to be nonlinear. The conductivity of phosphoric acid doped polyaniline sample is higher as compared to HCl doped polyaniline and pure polyaniline. Temperature dependence of conductivity suggests a semiconducting nature with increase in temperature. Activation energies have been found to be 50.86, 25.74 and 21.05 meV for pure polyaniline (base), polyaniline doped with hydrochloric, phosphoric acid, respectively. [ABSTRACT FROM AUTHOR]

Copolymer of aniline and formaldehyde has been synthesized by chemical oxidative polymerization using FeCl3 as an oxidant in aqueous acidic medium. Thermal transport properties like effective thermal conductivity (λe), effective thermal diffusivity (χe) and dynamic mechanical properties such as modulus (E′), loss tangent (tanδ) together with their temperature dependence have been investigated by transient plane source (TPS) method and dynamic mechanical analyzer (DMA) respectively. It has been found that both λe and χe increase with increase in temperature initially from room temperature to 80 °C and then decrease in the temperature range from 80 to 110 °C. For further increase in temperature λe & χe increase slightly and then attains a saturation value. The variation of modulus and loss tangent shows similar response and indicates a phase transformation at about 115 °C. This behavior of thermal transport properties is explained in terms of variation in mean free path of phonons arising due to structural changes in the material. Differential scanning calorimetry (DSC) was also performed to confirm the above said phase transformation. The results on phase transformation are in good agreement both by TPS and DMA. [ABSTRACT FROM AUTHOR]

Impregnating resins for use in fusion magnet technology are required to be radiation stable, have a long useable life together with some degree of toughness to minimise the risk of cracking during cool-down. Some multi-functional resins in combination with solid aromatic amines have, in the past, been shown to have lost little of their strength after a total absorbed dose of 200 MGy. Using resins that are known to be radiation stable with a liquid aromatic amine hardener, the effect of adding an aromatic epoxy resin as a reactive ‘toughening agent,’ to improve the toughness of otherwise brittle resins has been assessed. Boron free glass composites, using various amounts of added toughening agent were prepared by vacuum impregnation and a number of critical composite properties have been measured, at room temperature and at 77 K. [ABSTRACT FROM AUTHOR]

It is well-known that cooking of various meats at high temperatures results in the formation of compounds that are not present in uncooked meats. Heterocyclic aromatic amines (HCAs) are an important class of heatproduced compounds. They were found to be mutagenic and carcinogenic for animals and even for humans. The aim of this study was to measure the amount of HCAs in beef during very long time and high temperature cooking. After sample extraction from the model system by using Chromabond XTR and Chromabond PS-H+ cartridges the concentrations of HCAs¹ were separated by HPLC and measured by a mass spectrometry using mass selective detection mode. Six HCAs (IQ; MeIQ; 4,8-DiMeIQx; MeAαC; Trp-P-1; PhIP) were identified and quantified in the heated beef samples. The concentrations of these HCAs varied from undetectable levels to 50.4 ng g-1. MeAαC and Trp-P-1 were present in heated beef extracts at the highest concentrations, while the values for the amino imidazoazaarenes were lower. PhIP which is one of the most abundant HCAs in conventionally heated meat was found at rather high concentration. [ABSTRACT FROM AUTHOR]

Surface Enhanced Raman Spectroscopy (SERS) allows sensitive and selective detection of protease activity by monitoring the cleavage of specific peptide substrates. Furthermore, it offers the possibility for multiplexing, during which the activity of two (or more) proteases with different specificities is detected simultaneously. To distinguish between the contributions of different proteases, different aromatic amino acids with non-overlapping SERS peaks need to be used as Raman reporters. As the three natural aromatic amino acids only offer limited possibilities for multiplexing, we examined several non-natural aromatic amino acids with the aim of expanding multiplexing possibilities. We recorded their SERS spectra for the Raman shifts of 300-1700 cm–1 and identified their characteristic SERS peaks. Of the examined nonnatural aromatic amino acids, 3-nitro-tyrosine and two phenylalanines containing stable heavy isotopes seem particularly promising for multiplexing applications. Besides exhibiting characteristic SERS peaks in the spectral region of interest, these non-natural aromatics provide strong SERS peaks compared to natural aromatic amino acids, consequently improving detection sensitivity. [ABSTRACT FROM AUTHOR]

The synthesis of aromatic oligomers that imitate biopolymers in their structure and intend mimicking their outstanding functions constitutes a particularly rich field of chemistry nowadays. Quantum chemistry theoretical calculations could be valuable tools to elucidate hidden effects and to predict new structures with specific properties and capable of perform a particular function. In this context, recent works account for investigations of helical systems containing pyridine-pirimidine rings[1, 2] where the calculated electrical and magnetic responses present a predictive character. To this aim, semiempirical methods were used to evaluate first hyperpolarizabilities and rotational strengths of helical structures in conjunction with molecular mechanics methods to generate appropriate geometries. Several aspects were considered: the evolution of properties with the size of the system, the substitution and conformational effects to tune responses. Indeed the addition of aniline groups as substituents appears a good choice for the electric responses whereas their impact in magnetic responses remains to be investigated. [ABSTRACT FROM AUTHOR]

The article discusses the development of disperse dyes with the appearance of the hydrophobic fiber. It points to several methods of dyeing that were used briefly with reliance placed on accelerated fastness tests. It cites nylon as the second hydrophobic and first truly synthetic fiber on which disperse dyes were used and the polyesters which increased the number of and intensified the conditions which dyes must withstand. It indicates the two major classes of disperse dyes, namely the azo dyes that are prepared by a simple reaction of nitrous acid with an aromatic amine and the anthraquinones with lower tinctorial power. It notes that the dye chemistry born in 1923 has grown in stride with the progress in the textile use of hydrophobic fibers.

The main component of any explosive device is the secondary explosive, so the detection of the "key ingredient" is of central importance. It has established that small quantities of explosives are transferred to the hands or deposited on outer surfaces of letter bombs or packages during the assembly of the explosive device. The bulk of the explosives used in such manner, have sufficient vapor pressure and traces of the explosive are released in the atmosphere. One common feature of the organic-based secondary explosives is the presence of the nitro group. The nitro group (NO2) is electron-withdrawing and compounds that have one or more of them are expected to be good electron acceptors (A). In the presence of a good electron donor, D, (eg. aromatic amine) one can suspect a formation of electron donor-acceptor (EDA) complexes (also known as chargetransfer CT complexes). The goal of this project was to quantitatively explore the nature of the interaction between specially designed electron-rich aromatic amines Ar-NR2 (1-6) and the secondary explosives (or appropriate model compounds and taggants). Their synthesis will be presented along with the purification. The compounds 1-3 are spiroconjugated aromatic amines with unique interaction of the two perpendicular pisystems. From the obtained experimental results the compounds 2, 3 and 4 were too susceptible to oxidation for practical use. The most encouraging results were found with compound 5 (N-propyldansylamide) which is fluorescent and its fluorescence is quenched by volatile polynitroarenes and polynitrophenols. It also has a good solubility in dichloromethane and can be introduced in poly(methyl methacrylate) (PMMA) films. The PMMA films containing 5 are fluorescent and upon exposure of the vapors of taggant 2,3-dimethyl-2,3-dinitrobutane fluorescence quenching occurs. [ABSTRACT FROM AUTHOR]

An abstract of the article "TERS Studies Of Homogeneously Immobilized Aromatic Amino Acids," by Tanja Deckert-Gaudig, Eva Rauls and Volker Deckert is presented.