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Updated: Jun 14, 2025
07:20
Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
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Excited-State Cis and Trans Pt(IV) Diamine Anticancer Complexes
Huayun Shi1,2, Jana Kasparkova3,4, Fortuna Ponte5
1Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K.
Inorganic Chemistry
|May 28, 2025
Summary
New platinum complexes show promise as photochemotherapeutic anticancer drugs. The all-trans isomer is selectively activated by light to kill bladder cancer cells, with DNA not being the primary target.
Area of Science:
- Inorganic Chemistry
- Medicinal Chemistry
- Photochemistry
Background:
- Classical platinum(II) anticancer drugs like cisplatin rely on specific structures for activity.
- Existing platinum complexes and prodrugs demonstrate the potential of platinum in cancer therapy.
Purpose of the Study:
- To investigate the chemical and biological activities of isomeric photoactivatable platinum complexes.
- To compare the photocytotoxicity and mechanisms of action of cis,trans,cis- and all-trans-[Pt(N3)2(OH)2(MNZ)2] isomers.
Main Methods:
- Synthesis and characterization of isomeric platinum complexes.
- Evaluation of cytotoxicity in bladder cancer cells under visible light and hypoxia.
- DNA interstrand cross-linking assays and studies with nucleotide-excision-repair deficient cells.
- Time-dependent Density Functional Theory (DFT) calculations to explore photoactivation pathways.
Main Results:
- Both isomers are nontoxic in the ground state, but the all-trans isomer exhibits significant photocytotoxicity.
- The all-trans isomer is selectively activated by visible light, particularly under hypoxic conditions.
- Unlike cisplatin, DNA is not the primary target; the all-trans isomer binds to DNA, RNA, and proteins.
- Photoactivation of the all-trans isomer involves rapid azidyl radical generation and retention of metronidazole ligands.
- Increased accumulation in cancer cells, induction of apoptosis, and mitochondrial damage were observed for the all-trans isomer.
Conclusions:
- The all-trans-[Pt(N3)2(OH)2(MNZ)2] complex is a promising candidate for photochemotherapy.
- Its unique photoactivation mechanism and non-DNA-centric targeting offer new avenues for cancer drug design.
- Further research into these photoactivatable platinum complexes could lead to novel anticancer prodrugs.
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