A study to develop platinum(iv) complex chemistry for peptide disulfide bond formation

Area of Science:

• Inorganic Chemistry
• Medicinal Chemistry
• Peptide Chemistry

Background:

• Platinum(IV) complexes are explored for cancer treatment and chemical synthesis.
• Developing efficient methods for peptide disulfide bond formation is crucial for peptide chemistry.

Purpose of the Study:

• To synthesize and characterize novel platinum(IV) complexes.
• To investigate the application of these complexes as oxidants for peptide disulfide bond formation.

Main Methods:

• Synthesis and characterization of two platinum(IV) complexes: [PtCl2(phen)(en)]Cl2 and [PtCl2(bpy)(en)]Cl2 using elemental analysis, ESI-MS, and NMR.
• Investigation of the complexes' efficacy in forming disulfide bonds in various peptides under diverse conditions (aqueous solution, varying pH, room temperature).
• Exploration of their utility in both solution-phase and solid-phase (on-resin) synthesis.

Main Results:

• The synthesized platinum(IV) complexes were successfully characterized.
• Excellent purities and high yields of disulfide-containing peptides were achieved.
• The reactions proceeded rapidly across a wide pH range, including acidic conditions at room temperature.
• Intramolecular disulfide bonds were efficiently formed, enabling the generation of peptide libraries.
• The complexes proved effective for on-resin synthesis, facilitating automated peptide disulfide bond formation.

Conclusions:

• The developed platinum(IV) complexes are effective oxidants for synthesizing disulfide-containing peptides.
• These complexes offer a versatile and efficient method for peptide library generation and automated synthesis.
• The methodology is robust, functioning rapidly under mild, aqueous conditions.