ABSTRACT
Dithiobiureas coordination chemistry towards palladium (II) ions and their possible application is presented and discussed. 1,6-(4-Methoxyphenyl)-2,5-dithiobiurea and 1,6-(4-chlorophenyl)-2,5-dithiobiurea afford two Pd(II) complexes with the general formula [Pd2(H2L)Cl2(PPh3)2]. The metal ion forms one chelate ring with the dithiobiurea, and binds to a triphenylphosphine and an additional leaving group cisplatin like. One of the complexes (1) is endowed not only with stability in DMSO and aqua solutions containing a biological buffer but also with cytotoxicity versus gastric cancer cell lines. Complex 1 does not interact covalently to DNA models, neither activates p53 or Checkpoint Kinase 1 key proteins for DNA damage response. Thus, we propose that complex 1 exerts its action by activating Mitogen-Activated Protein Kinases [p38, Extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinases (JNKs)] as cell death inductors.
Subject(s)
Palladium , Signal Transduction , Palladium/pharmacology , Signal Transduction/physiology , Mitogen-Activated Protein Kinases/metabolism , Phosphorylation , JNK Mitogen-Activated Protein Kinases/metabolismABSTRACT
Thiosemicarbazones (TSCNs) constitute a broad family of compounds (R1R2C=N-NH-C(S)- NR3R4), particularly attractive because many of them display some biological activity against a wide range of microorganisms and cancer cells. Their activity can be related to their electronic and structural properties, which offer a rich set of donor atoms for metal coordination and a high electronic delocalization providing different binding modes for biomolecules. Heterocycles such as pyrrole, imidazole and triazole are present in biological molecules such as Vitamine B12 and amino acids and could potentially target multiple biological processes. Considering this, we have explored the chemistry and biological properties of thiosemicarbazones series and their complexes bearing heterocycles such as pyrrole, imidazole, thiazole and triazole. We focus at the chemistry and cytotoxicity of those derivatives to find out the structure activity relationships, and particularly we analyzed those examples with the TSCN units in which the mechanism of action information has been profoundly studied and pathways determined, to promote future studies for heterocycle derivatives.
Subject(s)
Anti-Bacterial Agents/pharmacology , Antineoplastic Agents/pharmacology , Antiparasitic Agents/pharmacology , Coordination Complexes/pharmacology , Heterocyclic Compounds/pharmacology , Neoplasms/drug therapy , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antiparasitic Agents/chemical synthesis , Antiparasitic Agents/chemistry , Coordination Complexes/chemical synthesis , Coordination Complexes/chemistry , Heterocyclic Compounds/chemical synthesis , Heterocyclic Compounds/chemistry , Humans , Metals, Heavy/chemistry , Metals, Heavy/pharmacology , Neoplasms/pathology , Thiosemicarbazones/chemistry , Thiosemicarbazones/pharmacologyABSTRACT
The synthesis and characterization of three new platinum complexes, with 3,5-diacetyl-1,2,4-triazole bis(4-N-isopropylthiosemicarbazone) as a ligand, are reported. The specific conditions under which solvent coordination takes place are reported and the X-ray structure of the complex with one solvent molecule of dimethyl sulfoxide is resolved. Analysis of the reactivity of these platinum compounds aids in finding the best solution profile for biological investigations. Then, the interactions of the complexes with biological models, such as calf-thymus DNA, are studied by using UV spectroscopy and tracking the changes in electrophoretic mobility produced in the supercoiled plasmid DNA model. Initial screening of these potential antitumoral compounds indicates possible selective antitumoral action.
