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New Heteroleptic RuII/Diphosphine Complexes with Cytotoxicity against Human Breast and Murine Ascitic Sarcoma 180 Tumor Cells
The preparation, characterization, theoretical calculations and biological application of four RuII complexes with 2-picolinate (pic), 2,2 ’ -bipyridine (bipy) and P-P as ligands [P-P = 1,1-bis(diphenylphosphino)methane (dppm-1), 1,2-bis(diphenylphosphino)ethane (dppe-2), 1,3-bis(diphenylphosphino)propane (dppp-3) or 1,1 ’ -bis(diphenylphosphino)ferrocene (dppf-4)], is here presented. The complexes 1-4, with general formula [Ru(pic)(P-P)(bipy)]PF6, were characterized by elemental analysis and by infrared (IR), UV-Vis, nuclear magnetic resonance (NMR 1H and 13P{1H}) spectroscopies, cyclic voltammetry and X-ray crystallo...
Source: Journal of the Brazilian Chemical Society - July 3, 2020 Category: Chemistry Source Type: research

Nanostructured Lipid Carriers Loaded with 17-α-Estradiol Accumulate into Hair Follicles
To improve 17- α -estradiol targeting in alopecia treatment, a formulation of nanostructured lipid carrier (NLC) prepared by the sonication method was developed. The physicochemical characterization showed an average diameter of 96 ± 15 nm and the average zeta potential of -17 ± 6 mV. In addition, the encapsulation efficiency (EE) of 17- α -estradiol, assessed by ultra-performance liquid chromatography (UPLC) fluorescence, was 99.6 ± 0.3%. Physical stability of NLC stored at room temperature was followed for 42 days through several physicochemical parameters, such as diameter, zeta potential, pH and EE. No changes wer...
Source: Journal of the Brazilian Chemical Society - July 3, 2020 Category: Chemistry Source Type: research

Synthesis, Characterization and in vitro, in vivo and in silico Anti-Inflammatory Studies of the Novel Hybrid Based on Ibuprofen and 3-Hydroxy-Copalic Acid Isolated from Copaiba Oil (Copaifera multijuga)
A novel anti-inflammatory hybrid 3-ibuprofenyl-copalic acid (3-IbuCA) was synthesized from 3-hydroxy-copalic acid isolated from Amazonian copaiba oil (Copaifera multijuga Hayne), and the anti-inflammatory ibuprofen. After full characterization, several assays to verify its anti-inflammatory effects were performed in vitro, in vivo and in silico (molecular docking). Induced fit docking was performed to observe the interactions with the enzymes cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2). In vitro tests of cytotoxicity and tumor necrosis factor (TNF)- α inhibition, and in vivo tests of pleurisy, protein expressio...
Source: Journal of the Brazilian Chemical Society - July 3, 2020 Category: Chemistry Source Type: research

Additions and Corrections
Fingerprints are unique to each individual, contributing to human identification in forensic cases. The powder technique being widely used is considered one of the most important in latent fingermarks analysis. In this sense, the present work aimed to synthesize 1-thiocarbamoyl-4,5-dihydro-1H-pyrazoles and apply them as powder agents to develop latent fingermarks. The compounds were prepared from an effective and green synthesis via the condensation of chalcones with thiosemicarbazide in ethanol under microwave irradiation. Pyrazoles were tested and compared with a standard white powder (Sirchie ®) on glass surfaces using...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Microwave Assisted Synthesis of Thiocarbamoylpyrazoles and Application as an Alternative Latent Fingermark Developers
Fingerprints are unique to each individual, contributing to human identification in forensic cases. The powder technique being widely used is considered one of the most important in latent fingermarks analysis. In this sense, the present work aimed to synthesize 1-thiocarbamoyl-4,5-dihydro-1H-pyrazoles and apply them as powder agents to develop latent fingermarks. The compounds were prepared from an effective and green synthesis via the condensation of chalcones with thiosemicarbazide in ethanol under microwave irradiation. Pyrazoles were tested and compared with a standard white powder (Sirchie ®) on glass surfaces using...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Occurrence of Pesticides Associated to Atmospheric Aerosols: Hazard and Cancer Risk Assessments
Since the 1950s, pesticides have been used in agriculture. The increase in their consumption has been observed in recent years. In this work, it was determined the concentration of pesticides in the atmosphere of S ão Paulo and Piracicaba cities (sugarcane plantation site) and the hazard quotients and cancer risk caused by inhalation of these compounds were calculated. Twenty-three samples were analyzed and 34 pesticides associated to atmospheric particulate matter (with diameter equal to or less than 2.5 (PM 2.5) and 10 µm (PM10)) were investigated by gas chromatograpy-mass spectrometry (GC-MS). Fourteen compounds inclu...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Synthesis, Characterization, and Synergic Photocatalytic Activity of Amorphous TiO2/Chitosan Carbon Microspheres
In this work, we report the synthesis and characterization of new amorphous graphene-like TiO2/chitosan carbon microspheres and its performance as photocatalyst. Four different carbon chitosan microspheres materials were obtained based on the distinctive procedure to incorporate TiO2 and TiOSO4 to chitosan structure by pyrolysis at 600 °C. Detailed characterizations were carried out using many different techniques, as thermogravimetric analysis/differential scanning calorimetry (TGA/DSC), scanning electron miscroscopy/energy dispersive X-ray spectroscopy (SEM/EDS), Fourier transform infrared spectroscopy (FTIR), X-ray pho...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Quantification of Arsenic, Cadmium, Mercury and Lead in Pineapple: Method Development, Validation and Evaluation of In-House Reference Materials
A method for quantification of arsenic, cadmium, mercury, and lead in pineapple using inductively coupled plasma-mass spectrometry (ICP-MS) was developed, validated, and used to test the homogeneity and stability of in-house reference materials. The method was tested at the regulation levels given by the Food and Agriculture Organization of the United Nations (FAO, 100 µg kg − 1). The mineralization conditions of the samples, in a microwave oven, were improved throughout the study of HNO3 and H2O2 concentrations, sample weight, time, and temperatures. The calibration was made by a gravimetric standard addition method wi...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Design, Synthesis and Antitubercular Activity of Novel Isoniazid-Cyclic-Amine-Azachalcones Hybrids
In this work, it is described the design of twenty-four heterocyclic amine-azachalcones compounds through molecular hybridization of chalcone scaffold and fragments of isoniazid, fluoroquinolones, and linezolid with antituberculosis potential. The new compounds were synthesized via Claisen-Schmidt condensation, providing yields of 36-95%. Fifteen compounds showed antituberculosis activity against Mycobacterium tuberculosis H37Rv strain. Two amine-azachalcones 15 and 17 showed relevant biological activity with minimum inhibitory concentration (MIC) values of 6.62 and 4.85 µM, respectively. Compound 12 showed the best profi...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Effect of Growth Parameters on the Photocatalytic Performance of TiO2 Films Prepared by MOCVD
The present study evaluated the main factors that influence the photocatalytic activity of titanium dioxide (TiO2) films grown by metalorganic chemical vapor deposition (MOCVD) at 400 and 500 °C, in different growth times. The photocatalytic behavior was analyzed by measuring the methyl orange dye degradation at different pH values. Structural and morphological characteristics, and the recyclability of the catalysts for several cycles were also investigated. Anatase phase was identified in all films. The higher photodegradation performances were obtained at acidic pH. The results demonstrated that the photocatalyst thick...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

New α-Hydroxy-1,2,3-triazoles and 9H-Fluorenes-1,2,3-triazoles: Synthesis and Evaluation as Glycine Transporter 1 Inhibitors
Two series of new compounds containing 1,2,3-triazole moiety were designed as putative GlyT1 inhibitors aiming the discovery of new hits with activity in cognitive disorders. 1,4-Disubstituted α -hydroxy-1,2,3-triazoles were obtained as racemates in moderate to good yields by the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction (click chemistry) as the key step between propargyl alcohols and aryl azides, previously prepared from anilines or boronic acids. Benzo[c]chromene-triazoles were planned to be obtained by palladium-catalyzed C − H activation using [bis(trifluoroacetoxy)iodobenzene] (PhI(TFA)2) of some...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

The Catalytic Action of Copper Ions and the Rosemary Extract Antioxidant Effect in the Biodiesel Oxidation Reaction and the Implication in Arrhenius Behavior
Biodiesel contains esters in its composition which make it susceptible to oxidation. Among the factors that cause this reaction is the contamination with metal ions. In the present work, it was analyzed biodiesel samples obtained from a mixture containing 39.0% m/m soybean oil, 22.0% m/m beef tallow and 39.0% m/m poultry fat using a methyl route. Copper ions were added to the biodiesel to evaluate its catalytic action in the oxidation reaction, in the presence and absence of rosemary extract. During 192 h of assay, samples containing copper, without extract, showed shorter induction periods, higher rate constants and lower...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Diethyl Selenodiglycolate: An Eco-Friendly Synthetic Antioxidant with Potential Application to Inflammatory Disorders
This study describes a single step, high yield and purity, ecofriendly and scalable procedure to prepare a selenium derivative (diethyl selenodiglycolate). Diethyl selenodiglycolate rapidly reduces hypochlorous acid (HOCl, second-order rate constant of 7 × 107 M − 1 s − 1) to generate its corresponding selenoxide. In activated HL-60 cells, diethyl selenodiglycolate selectively reacted with HOCl (half maximal inhibitory concentration (IC50) = 23.07 µM) but not with superoxide anion radical or hydrogen peroxide without any cytotoxicity. These results show that this synthetically simple selenide reacts in a very efficie...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Aqueous Extracts of the Castor Beans as a Corrosion Inhibitor of Mild Steel in HCl Media
The present work studied aqueous extracts of castor beans as a natural inhibitor of the corrosion of mild steel in 1 M HCl using gravimetric tests, potentiodynamic polarization curves, linear polarization method, electrochemical impedance measurements, surface analysis by scanning electron microscopy (SEM) and chemical characterization by Fourier transform infrared spectroscopy (FTIR). Gravimetric tests showed that inhibition efficiency (IE) increased with immersion time and concentration of the extract, reaching 97.8% in the presence of 800 mg L − 1 inhibitor after 24 h immersion time. For the gravimetric tests varying ...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research

Rapid Determination of Vitamins D2 and D3 in Dairy Products by High-Performance Liquid Chromatography after Solid Phase Extraction Based on Polystyrene/Polypyrrole Composite Nanofibers
The detection of vitamin D in complex samples is challenging because of the instability of vitamin D in sample preparation. To resolve this problem, packed-fiber solid-phase extraction (PFSPE) has been successfully developed for the pre-treatment of samples containing vitamin D2 (D2) and vitamin D3 (D3) in dairy products. Based on PFSPE, vitamin D could avoid oxidation because of the shorter extraction time. The adsorbent materials, polystyrene/polypyrrole (PS/PPy) nanofibers, were prepared by electrospinning of PS and in situ polymerization of PPy on the surface of PS nanofibers. The linearity was within the range of 1-20...
Source: Journal of the Brazilian Chemical Society - June 8, 2020 Category: Chemistry Source Type: research