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Naphtoquinones have been used as promising scaffolds for drug design studies against protozoan parasites. Considering the highly toxic and limited therapeutic arsenal, the global negligence with tropical diseases and the elevated prevalence of co-morbidities especially in developing countries, the parasitic diseases caused by various Leishmania species (leishmaniasis) became a significant public health threat in 98 countries. The aim of this work was the evaluation of antileishmanial in vitro potential of thirty-six 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinones obtained by a three component reaction of lawsone, the appropriate aldehyde and thiols adequately substituted, exploiting the in situ generation of o-quinonemethides (o-QM) via the Knoevenagel condensation. The antileishmanial activity of the naphthoquinone derivatives was evaluated against promastigotes and intracellular amastigotes of Leishmania (Leishmania) infantum and their cytotoxicity was verified in mammalian cells. Among the thirty-six compounds, twenty-seven were effective against promastigotes, with IC50 values ranging from 8 to 189 µM; fourteen compounds eliminated the intracellular amastigotes, with IC50 values ranging from 12 to 65 µM. The compounds containing the phenyl groups at R1 and R2 and with the fluorine substituent at the phenyl ring at R2, rendered the most promising activity, demonstrating a selectivity index higher than 15 against amastigotes. A QSAR (quantitative structure activity relationship) analysis yielded insights into general structural requirements for activity of most compounds in the series. Considering the in vitro antileishmanial potential of 2-hydroxy-3-phenylsulfanylmethyl-[1,4]-naphthoquinones and their structure-activity relationships, novel lead candidates could be exploited in future drug design studies for leishmaniasis.

The respective compounds of copper, cadmium and lead, owing to their strong toxic potential, as a result of industrial effluent, have left a trail of contamination in humans and the environment. This paper aimed to study the electrode position on the removal of aqueous solutions of cadmium, lead and copper, using an electrolytic cell with a metallic screen cathode of carbon steel and platinum anode. Removal efficiencies were obtained by analysis of the solutions before and after treatment, using the methodology of cathodic-stripping voltammetry with a mercury drop electrode to quantify the concentrations of Cd 2+ , Pb 2+ and Cu 2+. Removal efficiencies were obtained of 94.07% for cadmium, 94.71% for lead and 96.19% for copper, demonstrating that electrolytic removal is an effective technique for the removal of these metals from simulated industrial wastewater.

Industrial effluents containing cobalt ions have become a serious problem for the environment, unless properly treated, due to their toxic potential. Currently there has been an intensification of the use of cobalt in several industrial sectors as super alloys, catalysts, batteries and pigments in ceramic materials, and a consequent intensification also of environmental contamination. This paper aims to show a simple and effective treatment for the removal of cobalt ions from simulated industrial wastewater, based on cathodic eletrolytic removal using a carbon steel screen. As a result, a 73% removal of cobalt ions from solutions was achieved with a concentration of 400 mg Co 2+ /L, a current of 0.30 A and a voltage of 30 V. In the same conditions, 84% and 88% was removed from 200 mg Co 2+ /L and 100 mg Co 2+ /L, respectively. Thus, this method presents itself as a cheap and efficient alternative for the treatment of industrial effluents containing cobalt ions.

3D7). -None of the investigated compounds (III) exhibit better performance than respected control drugs. -(SHARMA, A.; SANTOS, I. O.; GAUR, P.; FERREIRA, V. F.; GARCIA, C. R. S.; DA ROCHA*, D. R.; Eur. J. Med. Chem. 59 (2013) 48-53, http://dx.