Síntese e caracterização de complexos fosfínicos de Zn(ii) e Ag(i) coordenados a ligantes planos

Abstract

The search for substances with potential anticancer and anti-parasitic diseases potential is becoming a major challenge for science. However, so far only a small number of synthesized compounds have managed to reach the clinical phase. Cisplatin and its derivatives represent a class of metal complexes with known antitumor activity, which has increased interest in the synthesis of these types of compounds, in addition to other substances used in the treatment of other illnesses such as trypanosomiasis and leishmaniasis. The study of the interaction between metal-based compounds with DNA has become important, since the connection with this biomolecule is one of the factors responsible for the biological activity of metallodrugs. Metal complexes that contain planar ligands such as dpq and dppz interacts with DNA via intercalation. Therefore, in this work, the synthesis and characterization of Ag(I) and Zn(II) coordination compounds were proposed with dipyrido[3,2-a:2′,3′- h]quinoxoline (dpq) and dipyrido[3,2-a:2′,3′-c]-phenazine (dppz) and auxiliary ligands such as phosphines 1,3,5- triaza-7-phosphaadamantane (PTA) and triphenylphosphine (PPh3) was carried out, the yields ranging from 42-88%. Their characterizations were made using infrared (IR), ultraviolet-visible (UV-Vis) spectroscopies, 1H and 31P nuclear magnetic resonance (NMR), mass spectrometry (ESI-MS), elemental analyses (carbon, nitrogen and hydrogen) and x-ray crystallography. Complex [Ag(PPh3)2(dppz)]NO3 was determined by X-ray. All metal complexes are proposed as tetracoordinated compounds, where the dpq and dppz are bound as bidentate ligands. Additionally, the evaluation of the possible interactions with the DNA were studied, finding that the interaction that took place between them was the intercalative mode. Compounds [Ag(PPh3)2(dppz)]NO3, [Ag(dppz)2]NO3 and [Ag(dpq)2]NO3 were tested against tumor cells. Preliminary results showed that they did not display significant activity against the tumor cell lines studied.