Towards new transition metal-based hypoxic selective agents for therapy and imaging

Area of Science:

• Coordination Chemistry
• Radiopharmaceutical Chemistry
• Medicinal Inorganic Chemistry

Background:

• Hypoxic tumor cells are resistant to conventional therapies.
• Selective delivery of cytotoxic agents to hypoxic environments is a key challenge in cancer treatment.
• Metal complexes offer tunable properties for targeted drug delivery.

Purpose of the Study:

• To develop metal complexes for selective delivery of nitrogen mustard-type molecules to hypoxic cells.
• To synthesize and characterize novel cobalt, rhenium, and copper complexes with potential anticancer activity.
• To investigate the hypoxic selectivity of these metal complexes using various analytical techniques.

Main Methods:

• Synthesis of cobalt(II) complexes with tripodal tetradentate ligands.
• Development of rapid, low-temperature synthetic routes for rhenium(V) and rhenium(III) complexes using hydrazines.
• Spectroscopic, cyclic voltammetric, and density functional (DF) calculations for mechanistic studies.

Main Results:

• Exploration of cobalt(II) lability for selective drug delivery.
• Successful synthesis of new rhenium(V) and rhenium(III) thiosemicarbazone complexes.
• Characterization of copper(II) bis(thiosemicarbazone) complexes and synthesis of new derivatives for hypoxic targeting.

Conclusions:

• Metal complexes, particularly copper(II) bis(thiosemicarbazone) derivatives, show promise for hypoxic selective delivery of cytotoxic agents.
• The lability of cobalt(II) and the properties of rhenium complexes warrant further investigation for cancer therapy applications.
• These findings contribute to the development of targeted cancer treatments by exploiting tumor microenvironment characteristics.