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The aim of this work was to investigate the mechanism of action of 2-ferrocenyl-1,1-diphenylbut-1-ene (1) on HL-60 human leukemia cells. While inactive against noncancerous cells, 1 provoked a concentration-dependent decrease in viable tumor cells, primarily via apoptosis, as evidenced by analysis of cell morphology, activation of caspases 3 and 7, increased DNA fragmentation, and externalization of phosphatidylserine. Necrosis was observed only at the highest tested concentration (4 μM). Compound 1 interfered with the cell cycle, causing an accumulation of cells in the G1 /G0 phase. Interaction of 1 with dsDNA and ssDNA was observed by differential pulse voltammetry and confirmed by hyperchromicity in the UV/Vis spectra of dsDNA, with an interaction constant of 2×10(4) M(-1). Both the organic analogue 1,1,2-triphenylbut-1-ene (2) and ferrocene were inactive against cancer and noncancer cell lines and did not react with DNA. These results reinforce the idea that the hybrid strategy of conjugating ferrocene to the structure of tamoxifen derivatives is advantageous in finding new substances with antineoplastic activity.

O comportamento eletroquímico do herbicida metribuzin foi estudado em solução aquosa com eletrodos de carbono vítreo, em pasta de carvão/nujol, carvão/óleo de mamona e pela utilização de voltametria cíclica, voltametria de onda quadrada, voltametria de pulso diferencial, coulometria e eletrólises em potencial controlado, para fins de quantificação e estudos de degradação. Os produtos majoritários obtidos a partir da eletrólise redutiva de metribuzin, após o consumo de 8,26 mol elétron mol-1 , foram o desaminometribuzin e o dicetometribuzin. A onda anódica observada após a eletrorredução está relacionada à oxidação do tiolato de metila, gerado no processo eletrolítico. Essa onda foi utilizada para a determinação quantitativa de metribuzin em amostra comercial, por meio de voltametria de redissolução anódica. De maneira a promover descontaminação, por eliminação do herbicida, o processo eletro-Fenton foi utilizado e levou a 80% de mineralização de metribuzin. The electrochemical behavior of the herbicide metribuzin was studied in an aqueous solution on glassy carbon, carbon paste/Nujol oil and carbon paste/castor oil using cyclic voltammetry, square-wave voltammetry, differential pulse voltammetry, controlled-potential coulometry and electrolysis, for quantification and decontamination purposes. The main electrolytic products obtained from the reduction of metribuzin, after consumption of 8.26 mol electron mol-1 , were deaminometribuzin and diketometribuzin. The anodic wave observed after electroreduction is associated with the oxidation of the methylthiolate generated in the electrolytic process. This wave was used to quantitatively determine metribuzin in a commercial sample by anodic stripping voltammetry. The electro-Fenton method was employed to promote decontamination by eliminating the herbicide, resulting in 80% of mineralization of the metribuzin.

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