Synthesis, antiproliferative activity and plasmid DNA interaction studies of [Pt(1-substituted-1H-1,3-diazole)2Cl2] and [Pt(1-substituted-1H-1,3-diazole)2I2] analogs

Researchers have accelerated subject their research on platinum complexes since the serendipitous discovery of cisplatin's anticancer properties. Their goal is to synthesize more potent platinum complexes by replacing the carrier ammonia ligands in the structure of cisplatin with biologically active heterocyclic compounds. 1H-1,3-Diazoles are heterocyclic compounds with a five-member ring structure well-known to biological systems. Their exceptional pharmacological activities have led to a remarkable place in recent years. Their exceptional pharmacological activities have led to a remarkable place in the past few decades. This approach is a key strategy for increasing the efficacy of cancer treatments and better-targeting cancer types that develop resistance to current therapies. In this study, six novel platinum(II) complexes with the structures of [Pt(L1)2Cl2] (1a), [Pt(L2)2Cl2] (1b), [Pt(L3)2Cl2] (1c), [Pt(L1)2I2] (2a), [Pt(L2)2I2] (2b), and [Pt(L3)2I2] (2c) (L1= 1-(4-methoxyphenyl)-1H-1,3-diazole, L2= 1-phenyl-1H-1,3-diazole and L3= 1-benzyl-1H-1,3-diazole) were synthesized for cisplatin analogues. The chemical structures of 1a-1c and 2a-2c were elucidated by Fourier Transform Infrared (FT-IR), Proton Nuclear Magnetic Resonance (1H-NMR), Electrospray Ionization Mass Spectrometry (ESI-MS), and elemental analysis. The interactions of the complexes with pBR322 plasmid DNA and BamHI and HindIII restriction endonuclease enzymes were investigated by agarose gel electrophoresis. The cytotoxic effects of 1a-1c and 2a-2c against human non-small cell lung cancer (A549), human colon adenocarcinoma (CaCo-2), and mouse fibroblast cells (L929) cells were tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Compound 2c was as effective as cisplatin against the CaCo-2 cell line with 17.27 IC50 values.