Preparación y caracterización de compuestos de inclusión entre Rh(III), Ni(II), 2-acetil piridina tiosemicarbazonas y β-ciclodextrina

Abstract

In this paper the preparation and characterization of inclusion compounds between 2-acetylpyridine thiosemicarbazone ligand (HAPTSC) and the complexes bis(2-acetylpyridine thiosemicarbazone)rhodium(III) chloride, [Rh(HAPTSC)2 ]Cl3 , and bis (2-acetylpyridine thiosemicarbazone)nickel(II) chloride, [Ni(HAPTSC)2 ] Cl2 , with β-cyclodextrin (βCD) as a strategy to improve the solubility and antimicrobial activity of these compounds. These compounds were prepared in a molar ratio 1:1 between the respective compound and βCD, and characterized by protonic nuclear magnetic resonance and carbon-13 (NMR 1 H, 13C) spectroscopy, absorption in the infrared (IR) region spectroscopy, thermal analysis (DTA/DSC) and X-ray diffraction in powder (XRD). The results obtained through these techniques indicate the formation of association compounds and/or partial inclusion between the ligant and the Rh(III) and Ni(II) metal complexes with βCD. Antimicrobial assays were carried out with the enclosed metal complexes and the free compounds against Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus, Bacillus subtilis) bacteria and two yeast (Candida albicans and Saccharomyces cerevisiae). The comparison of the antimicrobial activity of the βCD enclosed complex with the activity of the free compounds showed that the enclosed ligant increased its activity against S. aureus, whereas the enclosed Rh(III) compound increased its activity against P. aeruginosa. © Acad. Colomb. Cienc. Ex. Fis. Nat.  2015.