Anticancer Study on Ir^III and Rh^III Half-Sandwich Complexes with the Bipyridylsulfonamide Ligand

Area of Science:

• Organometallic Chemistry
• Medicinal Chemistry
• Biochemistry

Background:

• Organometallic half-sandwich complexes of iridium(III) and rhodium(III) were synthesized using a novel sulfonamide ligand.
• The structural characterization and coordination chemistry of these complexes were investigated.

Purpose of the Study:

• To explore the biological interactions of the synthesized sulfonamide ligand (L) and its iridium(III) (1) and rhodium(III) (2) complexes.
• To evaluate the potential therapeutic applications of these compounds.

Main Methods:

• Synthesis and crystal structure analysis of ligand (L) and complexes (1, 2).
• Spectroscopic techniques (e.g., NMR, IR, Mass Spectrometry) for characterization.
• In vitro studies involving carbonic anhydrase (CA), human serum albumin (HSA), CT-DNA, cancer cell lines, and non-malignant cells.

Main Results:

• Complex (1) showed no antiproliferative activity due to high glutathione (GSH) binding affinity.
• Ligand (L) exhibited competitive inhibition of CA, while complexes (1, 2) showed uncompetitive inhibition.
• All compounds interacted with HSA, altering its secondary structure, and compounds (L, 2) induced caspase-dependent cell death.

Conclusions:

• The sulfonamide ligand (L) and rhodium(III) complex (2) demonstrate promising cytotoxic effects.
• These compounds represent potential lead structures for further pharmaceutical and therapeutic research.