Presence Of Nitro Group Research Articles

Effect of cetyl pyridinium chloride on corrosion inhibition of mild steel in acidic medium

The corrosion inhibition behavior of cetyl pyridinium chloride (CPC) on mild steel (MS) in 0.5 M H2SO4 solution was examined using weight loss and potentiodynamic polarization method. Different concentrations of CPC (0.000192 M, 0.0038 M, 0.0057 M and 0.0077 M) was used to find the balanced CPC in the acid solution. Among them, 0.000192 M and 0.0077 M of CPC solution showed a corrosion rate of 8.23×10−3, 3.52×10−5 (mm/Year), and the inhibition efficiency of 89.94 % and 96.23 %, respectively, which is lower than the pure acidic solution (0.5 M H2SO4). Furthermore, the experimented MS surfaces were characterized by Fourier Transform Infrared Spectroscopy (FTIR), Field Emission Scanning Electron Microscopy (FESEM), and Atomic Force Microscopy (AFM). FESEM and AFM studies demonstrated the corrosion attack on the MS surface, which is relatively less as compared to the only acid-exposed surface. The SEM-EDX analysis indicates the presence of nitro-group on the MS surface, which might be due to the contribution of pyridinium protonation of CPC. This phenomenon might enhance the corrosion resistance on the MS surface.

Enhanced electrocatalytic activity of bismuth-doped lanthanum stannate pyrochlore for electrochemical detection of the Covid-19 drug nitazoxanide

Nitazoxanide (NAZ) is an antiparasitic drug that reduces inflammation caused by the SARS-CoV-2 virus. The presence of nitro group in this drug makes it an environmental pollutant. Here, an electrochemical sensor for the determination of NAZ was developed based on bismuth-doped pyrochlore lanthanum stannate nanoparticles modified screen-printed carbon electrodes (BLSO NPs/SPCE). The BLSO NPs were prepared by a combination of co-precipitation and thermal calcination processes. The fabricated BLSO NPs were analyzed by different spectroscopic methods. X-ray diffraction analysis (XRD), Fourier transform-infrared spectroscopy (FT-IR), and Raman spectroscopy showed that the lattice parameters of the lanthanum stannate nanoparticles (LSO NPs) were increased after bismuth doping due to cell expansion. The morphology and oxidation state of the elements in the BLSO NPs were analyzed by field emission-scanning electron Microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and X-ray photoelectron spectroscopy (XPS). FE-SEM and HR-TEM analysis revealed that LSO, and BLSO exhibits as a nanoparticle morphology with 20–50 nm in size. Cyclic voltammetry (CV) showed that the electrochemical reduction of NAZ was enhanced after bismuth doping due to the synergistic effect of BLSO NPs. Electrochemical determination of NAZ was performed by DPV with a low detection limit of 4 nM between the linear range of 0.01–172 µM and an electrode sensitivity of 0.16 µA µM−1 cm−2. The developed NAZ sensor showed favorable results in terms of selectivity, repeatability, and stability.

Chemodynamics of Polycyclic Aromatic Hydrocarbons and Their Alkylated and Nitrated Derivatives in the Yellow Sea and East China Sea.

The occurrence of continuously released polycyclic aromatic hydrocarbons (PAHs) in marginal seas is regulated by hydrological and biogeochemical processes; however, scarce knowledge is about their derivatives in marine environments. In this study, the dissolved and particulate PAHs and their alkylated/nitrated derivatives (A-PAHs/N-PAHs) in surface seawater of the southwestern Yellow Sea (YS) and northwestern East China Sea (ECS) during September 2022 were comprehensively discussed. Results confirm higher levels of Σ26PAHs (9.3-70 ng/L) and Σ43A-PAHs (13-76 ng/L) than Σ20N-PAHs (0.80-6.6 ng/L). The spatial heterogeneity of contaminants was regulated by substantial riverine runoff and ocean currents. Lagrangian Coherent Structure analysis further revealed the existence of a transport barrier at the shelf break of the southwestern YS where contaminants hardly crossed and tended to accumulate. The relationship between dissolved compounds and chlorophyll a indicated both biodegradation and the biological pump contributed to the depletion of PAHs and A-PAHs from surface seawater while the biological pump was the major driver for N-PAHs, despite their complicated water-particle partition behavior due to variations in physicochemical properties in the presence of nitro groups. Source identification demonstrated that pyrogenic and petrogenic sources dominated the YS and ECS, respectively, while photochemical transformations appeared more active in the YS.

Trinitroaromatic explosives: Modern application, toxicological characterization, and methods of determination

Explosives such as tetryl and picric acid, which were common in the past, now have lost their combat relevance. However, they are often used for peaceful purposes individually and in combination with other trinitroaromatic compounds (e.g., trinitrotoluene). As a result of their use, environmental pollution occurs, followed by intoxication of plants, animals, and people. Cases of explosive poisoning during their production are also described.
 The symptoms of poisoning include both of general disorders and specific phenomena such as skin staining, impaired physiological efficiency of NADPh-dependent enzymes, genotoxicity, and immunotoxicity.
 Previous scientific studies established a trend toward the development of chemical-analytical probes. Various options for the sensor surface of the device and methods for detecting compounds are considered. To determine the explosives, ion mobility spectrometry is widely used, which is very rare for the chemicaltoxicological analysis of other groups of compounds.
 Simultaneously, methods commonly used in the analysis of narcotic and psychotropic substances (gas chromatography/ combination of high-performance liquid chromatography and mass spectrometry methods) are also applicable to determine trinitroaromatic explosives. However, the presence of nitro groups in their structure complicates such an analysis. This problem can be resolved by injecting cold samples directly to the column.
 Despite the availability of various developed techniques and methods, the possibility of their application to study biological matrices remains insufficient.
 Therefore, further studies of the chemicaltoxicological nature should be conducted to establish the optimal conditions for extracting the substances in question, the parameters of instrumental analysis, and the possibility of storing samples and for solving other problems of forensic medical examination.

Structures, Characterization and DFT Studies of Four Novel Nickel Phenanthroline Complexes

Four Ni–phen complexes were prepared and characterized by FTIR and thermal analysis. The X-ray structure determination shows that the geometry around NiII ions in complexes 1, [Ni(phen)2(H2O)(ONO2)](NO3); 2, [Ni(phen)2(H2O)Cl]Cl; 3, [Ni(phen)(CH3CN)(ONO2)(O2NO)] and 4, [Ni(phen)3](NO3)2.H2O.C2H5OH is considerably distorted octahedral. The coordination core geometries in 1, 2, 3 and 4 are NiN4O2, NiN4OCl, NiN3O3 and NiN6, respectively. The crystal packing and crystal supramolecularity analysis of the complexes reveal the importance of aryl∙∙∙aryl interactions, and both offset face-to-face (OFF) and edge-to-face (EF) motifs are dominant. Hydrogen bonding interactions in these structures reinforce aryl∙∙∙aryl interactions. FTIR proved the coordination of M-N and M-Cl as well as the presence of nitro groups in the complexes, while thermal analysis revealed that the loss of water, chloro and nitro groups occurred before the degradation of phenanthroline ligand in the complexes. DFT study indicates that a strong correlation exists among theoretical and experimentally determined geometric parameters with distorted octahedral geometry. The charge density in HOMO is localized on the metal halogen bond and nitrate group (NO3−), whereas the LUMO cloud density is mainly distributed on the phen ring, which indicates the electroactive nature of the ring.

In vitro evaluation of the selective cytotoxicity and genotoxicity of three synthetic ortho-nitrobenzyl derivatives in human cancer cell lines, with and without metabolic activation

Although the presence of nitro groups in chemicals can be recognized as structural alerts for mutagenicity and carcinogenicity, nitroaromatic compounds have attracted considerable interest as a class of agents that can serve as source of potential new anticancer agents. In the present study, the in vitro cytotoxicity, genotoxicity, and mutagenicity of three synthetic ortho-nitrobenzyl derivatives (named ON-1, ON-2 and ON-3) were evaluated by employing human breast and ovarian cancer cell lines. A series of biological assays was carried out with and without metabolic activation. Complementarily, computational predictions of the pharmacokinetic properties and druglikeness of the compounds were performed in the Swiss ADME platform. The MTT assay showed that the compounds selectively affected selectively the cell viability of cancer cells in comparison with a nontumoral cell line. Additionally, the metabolic activation enhanced cytotoxicity, and the compounds affected cell survival, as demonstrated by the clonogenic assay. The comet assay, the cytokinesis-block micronucleus assay, and the immunofluorescence of the γ-H2AX foci formation assay have that the compounds caused chromosomal damage to the cancer cells, with and without metabolic activation. The results obtained in the present study showed that the compounds assessed were genotoxic and mutagenic, inducing double-strand breaks in the DNA structure. The high selectivity indices observed for the compounds ON-2 and ON-3, especially after metabolic activation with the S9 fraction, must be highlighted. These experimental biological results, as well as the theoretical properties predicted for the compounds have shown that they are promising anticancer candidates to be exploited in additional studies.

Relating algal-derived extracellular and intracellular dissolved organic nitrogen with nitrogenous disinfection by-product formation

The dissolved organic nitrogen (DON) pool from algal-derived extracellular and intracellular organic matter (EOM and IOM) comprises proteins, peptides, free amino acids and carbohydrates, of which, proteins can contribute up to 100% of the DON. Previous reports of algal-derived DON character have focused on bulk properties including concentration, molecular weight and hydrophobicity. However, these can be similar between algal species and between the EOM and IOM even when the inherent molecular structures vary. A focus on bulk character presents challenges to the research on algal-derived nitrogenous-disinfection by-product (N-DBP) formation as N-DBP formation is sensitive to the changes in molecular structure. Hence, the main aim of this study was to characterize algal EOM and IOM-derived DON, specifically proteinaceous-DON, using a combination of bulk and molecular characterization techniques to enable a more detailed exploration of the relationship between the character of algal-derived proteins and the N-DBP formation potential. DON from the EOM and IOM of four commonly found algae and cyanobacteria in natural waters were evaluated, namely Chlorella vulgaris, Microcystis aeruginosa, Dolichospermum circinale, and Cylindrospermopsis raciborskii. It was observed that 77-96% of total DON in all EOM and IOM samples was of proteinaceous origin. In the proteins, DON concentrations were highest in the high molecular weight fraction of IOM-derived bulk proteins (0.13–0.75 mg N L−1) and low to medium molecular weight fraction of EOM-derived bulk proteins (0.15–0.63 mg N L−1) in all species. Similar observations were also made via sodium dodecyl sulphate polyacrylamide gel electrophoresis and liquid chromatography-high resolution mass spectrometry. Solid-state 15N nuclear magnetic resonance (NMR) spectroscopy of the EOM and IOM revealed the existence of common aliphatic and heterocyclic N-groups in all samples, including a dominant 2° amide peak. Species dependent variability was also observed in the spectra, particularly in the EOM; e.g. nitro signals were found only in the Cylindrospermopsis raciborskii EOM. Dichloroacetonitrile (DCAN) and N-nitrosamine concentrations from the EOM of the species evaluated in this study were lower than the guideline limits set by regulatory agencies. It is proposed that the dominant 2° amide in all samples decreased N-DBP formation upon chlorination. For chloramination, the presence of nitro groups and aliphatic and heterocyclic N-DBP precursors could cause variable N-nitrosamine formation. Compared to non-algal impacted waters, algae-laden waters are characterised by low organic carbon: organic nitrogen ratios of ∼7–14 and elevated DON and protein concentrations. Hence, relying only on bulk characterization increases the perceived risk of N-DBP formation from algae-laden waters.

Highly dispersed palladium nanoparticles supported on graphitic carbon nitride for selective hydrogenation of nitro compounds and Ullmann coupling reaction

High catalytic activity and superior stability are important criterion for the utilization of a noble metal‐based nano‐composite catalyst. Herein, we report a facile synthesis of highly dispersed palladium nanoparticles embedded on graphitic carbon nitride (Pd@CNx) by ultrasound assisted method without aid of any external reducing agent. The Pd@CNx composite was well characterized by different techniques. This Pd@CNx shows effective catalytic activity towards easy dehydrogenation of sodium borohydride (NaBH4) and ammonia borane in aqueous medium and also can easily hydrogenate 4‐nitrophenol to 4‐aminophenol with fast kinetics. The catalyst is highly selective towards nitro groups in presence of other reducible groups with good stability. Furthermore, the catalyst exhibits superior catalytic activity towards Ullmann coupling reaction of different aryl halides with broad range of substrates scope with easy recovery of the catalyst and notable recycling property.

Recent Advances in Hydrogenation Reactions Using Bimetallic Nanocatalysts: A Review

AbstractHydrogenation reactions have been studied for many decades now and have developed from reactions that appear simple to now being recognized for their many complexities. These reactions are generally catalyzed using monometallic and more recently, with bimetallic nanocatalysts. Hydrogenation plays a vital role in food, chemical, petrochemical, pharmaceuticals, and dye industries to name a few. The hydrogenated products derived from several biomass‐based compounds are potential fossil fuels. Such products when employed in daily life, can help conserve natural resources. While hydrogenation of alkynes and alkenes are among the simplest of hydrogenation reactions, the most extensive and elegant manifestation of this reaction is seen in polymerization. Polymers like polythene, polypropylene (plastic) have replaced materials like glass, stainless steel, etc., in making daily use items for the obvious advantages of the former. Purification of alkenes is achieved by partially hydrogenating the respective alkynes present in trace amounts. This serves as an important step in the polymerization process. The presence of nitro group on aromatic rings makes them carcinogenic in nature which harms living organisms. For a safe environment, the elimination or modification of this nitro group becomes imperative. The products of hydrogenation of nitroaromatics and amino aromatics form the basis of pharmaceuticals and dyestuffs. A plethora of bimetallic catalysts have been used to catalyze these hydrogenation reactions. These catalysts are evaluated based on their selectivity and efficiency. This review highlights the recent advancements in the field of hydrogenation of nitro compounds, carbonyl compounds, and unsaturated hydrocarbons catalyzed by bimetallic nanoparticles.

Biological Activity of Newly Synthesized Benzimidazole and Benzothizole 2,5-Disubstituted Furane Derivatives.

Newly designed and synthesized cyano, amidino and acrylonitrile 2,5-disubstituted furane derivatives with either benzimidazole/benzothiazole nuclei have been evaluated for antitumor and antimicrobial activity. For potential antitumor activity, the compounds were tested in 2D and 3D cell culture methods on three human lung cancer cell lines, A549, HCC827 and NCI-H358, with MTS cytotoxicity and BrdU proliferation assays in vitro. Compounds 5, 6, 8, 9 and 15 have been proven to be compounds with potential antitumor activity with high potential to stop the proliferation of cells. In general, benzothiazole derivatives were more active in comparison to benzimidazole derivatives. Antimicrobial activity was evaluated with Broth microdilution testing (according to CLSI (Clinical Laboratory Standards Institute) guidelines) on Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. Additionally, Saccharomyces cerevisiae was included in testing as a eukaryotic model organism. Compounds 5, 6, 8, 9 and 15 showed the most promising antibacterial activity. In general, the compounds showed antitumor activity, higher in 2D assays in comparison with 3D assays, on all three cell lines in both assays. In natural conditions, compounds with such an activity profile (less toxic but still effective against tumor growth) could be promising new antitumor drugs. Some of the tested compounds showed antimicrobial activity. In contrast to ctDNA, the presence of nitro group or chlorine in selected furane-benzothiazole structures did not influence the binding mode with AT-DNA. All compounds dominantly bound inside the minor groove of AT-DNA either in form of monomers or dimer and higher-order aggregates.

QSAR modeling of algal low level toxicity values of different phenol and aniline derivatives using 2D descriptors

The deposition of different types of phenol and aniline derivatives in the aquatic environment leads to toxicity to living organisms. Under such condition, evaluation of these toxicants is very much important. Due to non-availability of sufficient experimental data as well as sufficient number of Quantitative Structure-Activity Relationship (QSAR) models for the low level toxicity values for such pollutants, we have employed here the partial least squares (PLS) regression for the development of robust and predictive QSAR models using low level toxicity values against algal species. Here, we have used both Extended Topochemical Atom (ETA) and non-ETA indices as 2D descriptors for model development. The statistical validation parameters ensure the robustness and the predictivity of the developed models. From the insights of the final PLS models, it can be concluded that presence of nitro groups (in the ortho position to phenolic hydroxyl group increasing intramolecular hydrogen bonding capacity), presence of chlorine substituents (influencing lipophilicity) especially at the para position, oxygen and nitrogen at the topological distance three, aliphatic side chain (contributing to hydrophobicity), molecules with large size atoms and higher molecular bulk will increase the toxicity towards the algal species. On the other hand, the phenol ring without any substituent or with a polar substituent (like amino group), presence of chlorine at ortho-ortho or ortho-para position, absence of nitro group, presence of chlorine and oxygen at the topological distance three, presence of lower number of aliphatic groups will decrease the toxic effect towards the algal species.

A density functional theory investigation of degradation of Nitroguanidine in the photoactivated triplet state.

It is well known that nitroguanidine (NQ) undergoes photodegradation when exposed to UV-radiation. However, the mechanism of NQ photolysis is not fully understood. Earlier investigations have shown that nitrocompounds undergo to their triplet state population through crossing of electronic singlet and triplet excited state potential energy surfaces due to the nitrogroup rotation and nonplanarity under electronic excitation. Therefore, it is expected that under electronic excitation, the presence of nitrogroup in NQ would also lead to the population of electronic lowest energy triplet state. To shed a light on the degradation of NQ in alkaline solution under electronic excitation, we performed a detailed investigation of a possible degradation mechanism at the IEFPCM/B3LYP/6-311++G(d,p) level in the electronic lowest energy triplet state. We found that degradation ability of NQ in the electronic triplet state would be significantly larger than in the electronic ground singlet state. It was revealed that the photodecomposition of nitroguanidine might occur through several pathways involving N-N and C-N bond ruptures, nitrite elimination, and hydroxide ionattachment. Nitrogen of nitrogroup would be released in the form of nitrite and nitrogen (I) oxide. Computationally predicted intermediates and products of nitroguanidine photolysis such as nitrite, hydroxyguanidine, cyanamide, and urea correspond to experimentally observed species.

A Naked-Eye Fluoride Ion Recognition Based Vanilin Derivative Chemosensors

Two new receptors S2 and S6 were designed and synthesized based on benzimidazole and azo-benzimidazole synthesized from vanillin for the colorimetric detection of fluoride ion. The presence of nitro group in S2 and azo in S6 makes –OH proton (binding site) acidic and therefore it could deprotonate with addition of basic anion such as fluoride. Hydroxyl (–OH) functionality which detects basic fluoride ions via hydrogen-bonding mechanism wich is mechanism involved in the color change of receptor R2 and R6, its mean that initial hydrogen bond formation of F− ion with –OH group.

Selective reduction of nitro group using CuNi bimetallic nanoparticles

Bimetallic nanoparticles have shown a lot of promise as catalysts in the recent years. This piece of work highlights the use of nanocatalyst for the chemoselective reduction of nitro group in presence of other reducible functional groups. CuNi bimetallic nanoparticles of varying composition (1:1, 1:2) have been synthesized by polyol method using metal sulphates with hydrazine hydrate as reducing agent. The characterization of synthesised nanoparticles was done by XRD and FESEM with EDX, which confirm FCC structure and composition of synthesised bimetallic nanoparticles. Particle size varies with composition i.e. 23 nm for (1:1) and 20 nm for (1:2). The selective reduction of p-nitrophenol, p-nitrobenzaldehyde and 2,4 dinitrophenol was performed in water using both single Ni nanoparticles and bimetallic CuNi nanoparticles (1:1, 1:2) with hydrazine hydrate as reducing agent at room temperature. The various amino products obtained has various industrial applications. UV–visible spectroscopy was used to monitor the progress of the reaction. The bimetallic nanoparticles facilitated the rate of reaction much as compared to single Ni nanoparticles.

Synthesis of Novel α-amidino Carboxylic Acids and their Use as H-Bond Catalysts in Strecker Reaction.

A wide variety of synthesized amidine derivatives are bioactive compounds. They show a vast range of medical properties. Therefore, a simple route for synthesis of novel class of amidine derivatives called amidino carboxylic acids and their use as catalysts in Strecker reaction has been reported in the current work. The stability, local charge density and hydrogen bond parameters were calculated for eight derivatives with different substituents. In order to synthesize these amidino carboxylic acids, we initially prepared Knovenogel condensation products via the reaction of isatin derivatives with malonitrile. When the reaction was performed in water, the resulting nitrile groups of malonitrile derivatives was hydrolyzed with HOAC/ H2SO4 to generate the desired amide groups. The amide groups in resulting compound converted to amine groups with two Hoffman rearrangements in the presence of NaOH/Br2. Further neutralization led to the final zwitterionic α-amidino carboxylic acids. In the next step, the catalytic activity of these compounds as H-bond donor catalyst was investigated in Strecker reaction. The overall yields of the derivatives with substituent on the aromatic ring of starting isatins are higher than that for the overall yields of nitrogen-substituted isatins. The reaction of 5-nitro isatin with the next reagent gives lower yield in aryl-substituted products. An increase of catalytic activity is observed by rising the electron-withdrawing power of the aromatic ring substituents., The presence of nitro group in the structure of catalyst caused a large increase of catalytic activity in Strecker reaction. DFT calculations at B3LYP/6-31++g(d,p) and Lanl2dz level of theory showed that these compounds act as single H-bond catalysts and higher yields were obtained for complexes with stronger hydrogen bond. A simple and efficient method for synthesis of ɑ-amidino carboxylic acids was developed in this research. These compounds have been used as a single H-bond donor catalyst in the Strecker reaction. DFT calculations were carried out to confirm the experimental results. The obtained data from computations are in good agreement with experimental results.

3-Nitro-2-phenyl-2-(trifluoromethyl)-2H-chromenes in reaction with N-methylazomethine ylide: stereoselective synthesis of 3a,4,4-trisubstituted chromeno[3,4-c]pyrrolidines

1,3-Dipolar cycloaddition of unstabilized azomethine ylide obtained in situ from sarcosine and paraform occurred stereoselectively at the double bond of 3-nitro-2-phenyl-2-(trifluoromethyl)-2H-chromenes activated by the presence of nitro group. The synthetic procedure required refluxing in benzene for 2 h and gave chromeno[3,4-c]pyrrolidines with trans configuration of trifluoromethyl group and nitro group as the major products. The structure of the obtained products was confirmed by X-ray structural analysis.

Chemoselective transfer hydrogenation of nitroarenes, ketones and aldehydes using acylthiourea based Ru(II)(p-cymene) complexes as precatalysts

A new series of Ru(II)(η6-p-cymene) complexes (1–5) was synthesized from pyridine based acylthiourea ligands (L1-L5) and [Ru(η6-p-cymene)Cl2]2. All the ligands and complexes were well characterized by UV-Visible, FT-IR, mass and 1H &13C NMR spectroscopic techniques. The molecular structures of the ligands (L1, L2, L4, and L5) and complex 1 were confirmed using single crystal X-ray diffraction study. The Ru(II)(η6-p-cymene) complexes (1–5) were proved to be efficient precatalysts for the transfer hydrogenation of carbonyl compounds and nitroarenes in the presence of 2-propanol as a hydrogen donor and KOH as a base. The catalytic transfer hydrogenation reactions were chemoselective towards the nitro group in presence of carbonyl group, which is a rare scenario in homogeneous catalysis. The catalyst was compatible with broad range of substrates which include furfural, quinone and many heterocycles. The catalytic reactions exhibited very high conversions (upto 100%) and excellent yields (upto 99%). Turn Over Number (TON) was found upto 990.

A selective chemosensor for fluoride ion and its interaction with Calf Thymus DNA

The amido-Schiff base 1 (N1, N3-bis (2-nitrobenzylidene)benzene-1,3-dicabohydrazide) containing a CONH group and CHN linkage has been synthesized by the condensation between isophthalic acid dihydrazide and o-nitrobenzaldehyde. This molecule can act as a fluoride ion sensor with high selectivity and sensitivity. Presence of nitro group in the phenyl ring may be responsible for the detection of fluoride ion visually with a dramatic color change from colorless to deep red in aqueous dimethyl sulphoxide solution. This Schiff base can be used as test kit for sensing of fluoride ion in the solid state. Compound 1 can detect fluoride also in commercially available toothpaste. As the compound has adequate solubility in DMSO–water mixture (7:93, v/v) and having some hydrogen bond donor and acceptor centers, we have investigated its nature of binding with Calf Thymus-DNA (CT-DNA) using theoretical molecular modelling and other experimental methods like UV–vis spectroscopy, circular dichroic and thermal melting studies. Thermodynamic parameters have been obtained using the well known Van't Hoff's equation. From both theoretical and experimental findings it has been observed that it can interact effectively with CT-DNA with binding energy −7.55kcal/mol to −7.50kcal/mol.

Enhanced Degradation of 4-Nitrotoluene byRhodococcus pyridinivoransNT2: Multivariate Optimization of Process Parameters and Evaluation of Biokinetic Parameters

Abstract 4-Nitrotoluene (4-NT) is widely used as a basic chemical for the manufacturing of a variety of intermediates, and exposure to this compound can cause environmental and health hazards. Bacterial transformation of 4-NT is often limited due to the presence of nitro group and substrate inhibition. The aim of this study was to optimize the biodegradation of 4-NT and specific growth rate of Rhodococcus pyridinivorans NT2 using Plackett-Burman and response surface methodology design of experiments. Of the process variables screened, 4-NT, MgSO4.7H2O, temperature, and inoculum size (OD) were selected as the most important (p < 0.05) factors. On the basis of central composite design, optimum conditions for 4-NT degradation were as follows: 480 mg/L 4-NT, 0.11 g/L MgSO4.7H2O, 37.5°C temperature, and 1.05 OD inoculum size. Under these culture conditions, an overall 1.20-fold increase in degradation was achieved with a 36 h reduction in total biodegradation time than that obtained at the unoptimized settings...

Novel derivatives of nitro-substituted salicylic acids: Synthesis, antimicrobial activity and cytotoxicity

Inspired by the high antituberculous activity of novel nitro-substituted derivatives and based on promising predicted ADMET properties we have synthesized a series of 33 salicylanilides containing nitro-group in their salicylic part and evaluated them for their in vitro antimycobacterial, antimicrobial and antifungal activities. The presence of nitro-group in position 4 of the salicylic acid was found to be beneficial and the resulting molecules exhibited minimum inhibitory concentrations (MICs) ranging from 2 to 32μM against Mycobacterium tuberculosis. The best activity was found for 2-hydroxy-4-nitro-N-[4-(trifluoromethyl)phenyl]benzamide (MIC=2μM). 4-Nitrosalicylanilides were also found to be active against all Staphylococcus species tested while for MRSA strain 2-hydroxy-4-nitro-N-[4-(trifluoromethyl)phenyl]benzamide’s MIC was 0.98μM. None of the nitrosalicylanilides was active against Enterococcus sp. J 14365/08 and no considerable activity was found against Gram-negative bacteria or fungi. The hepatotoxicity of all nitrosalicylanilides was found to be in the range of their MICs for HepG2 cells.