Over the years, several drugs have been developed deriving from plants to investigate possible therapeutic roles. Among them, curcuminoids and coumarins, which, display a wide range of biological activity against several strains. Therefore, it was synthesized a curcuminoids-coumarin derivative by a mechanochemical multicomponent reaction. By NMR and HRMS results confirmed the formation of a mixture of three curcuminoids-coumarin derivatives in the same sample. The Influence of time during the milling process was evaluated, resulting in a crystalline product in only 30 min. The LAG milling carried out with different solvents showed that the product is obtained regardless of the solvent polarity. Furthermore, the biological evaluation showed that the curcuminoidscoumarin derivative has better activity against S. aureus than curcumin and 4-hydroxycoumarin. Lastly, the cell viability study exhibited a decrease of cytotoxicity of the derivative, compared to curcumin, against NIH3T3 cells.

Grape seed is a waste product from the wine and juice industries. However, vegetable oil can be extracted from it, which is a renewable chemical with a huge potential application after chemical modifications, such as epoxidation and maleinization processes. This paper therefore deals with the use of grape seed oil, to produce its epoxidized and maleinized derivatives. Both derivatives were synthesized in order to improve the conversion (99.4%), yield (98.9%) and selectivity (99.5%) values, as well as to decrease the reaction time (3 h) using cleaner energy sources and heterogeneous catalysts, which can be used 4× without regeneration and obtaining similar conversion and yield values, and at least 5× keeping high selectivity. Based on the characterization results, both grape seed oil derivatives may be applied in different fields, including polymer chemistry as a monomer, coating, and paint. In addition, they can be an option to industries that use petrochemical derivatives as precursors.

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This work aims to determine if thermogravimetry could be used to determine the degree of conversion of soybean oil to biodiesel without knowing the amount of ester in the sample, comparing the results with the values obtained by the standard method, gas chromatography. The syntheses were made using homogeneous and heterogeneous catalysts, and the measures were made in triplicate on both pieces of equipment. The average values (%) obtained were 74.59 ± 0.58, 66.5 ± 1.62, 13.54 ± 0.32 by thermogravimetry and 74.09 ± 0.46, 62.08 ± 2.19, 17.07 ± 0.31 by gas chromatography. These data were statistically compared using F-test, and the result indicated that the thermogravimetry could be used as analytical technique to determine the degree of conversion of biodiesel, with the same reliability as gas chromatography. The thermogravimetry shows more advantages than gas chromatography, because it does not require organic solvent, following the Green Chemistry Principles, and it is already used to determine other thermal properties of biodiesel.

Coordination compounds of transition metals with norfloxacin (Nor) have potential to improve its effectiveness, as already discussed for some compounds found in the literature. The complexes in the solid state were prepared by precipitation of the respective metal cation (M = Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)) with a norfloxacin sodium salt solution. The thermal behavior under oxidative and pyrolysis conditions was investigated employing thermogravimetry and differential thermal analysis (TG/DTG-DTA) and evolved gas analysis (EGA/TG-FTIR), and the complexes were characterized by elemental analysis (EA), EDTA complexometric titration, infrared spectroscopy (FTIR) and X-ray powder diffraction (XRD). By these results, the minimum formula was established as [M(Nor) 2 (H 2 O) 2 ]ÁnH 2 O, where n = 3 (Ni), 2.5 (Mn Co, Zn), or 2 (Cu). The evolved gases identified during thermal decomposition of Ni and Cu complexes were ethylene, CO 2 and CO for Ni; CO 2 and ethane for Cu. Also, antimicrobial activity of the complexes was evaluated by in vitro susceptibility test using the agar diffusion method, and the results were compared with the uncomplexed molecule. It was found that norfloxacin complexation modifies its antibacterial activity. The activity depends on the type of metal ion and microorganism; Mn(II), Co(II) and Zn(II) complexes significantly increased activity against the tested gram-negative bacteria.

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