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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
Spirodiazaselenuranes: synthesis, structure and antioxidant activity
Devappa S Lamani1, Debasish Bhowmick, Govindasamy Mugesh
1Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560 012, India.
Organic & Biomolecular Chemistry
|August 31, 2012
Summary
Researchers synthesized novel spirodiazaselenuranes with significant glutathione peroxidase (GPx) and peroxynitrite scavenging activities. Substituent effects on GPx activity were explored, revealing electron-donating groups enhance efficacy.
Area of Science:
- Organoselenium chemistry
- Medicinal chemistry
- Biochemistry
Background:
- Selenium compounds are known for their antioxidant properties.
- Glutathione peroxidase (GPx) and peroxynitrite (PN) are crucial in cellular redox homeostasis.
- Developing novel antioxidants is vital for combating oxidative stress.
Purpose of the Study:
- Synthesize and characterize novel spirodiazaselenuranes.
- Evaluate their glutathione peroxidase (GPx) mimetic activity.
- Assess their peroxynitrite (PN) scavenging capabilities.
Main Methods:
- Oxidative cyclization of diaryl selenides to form spiro compounds.
- Characterization using NMR, mass spectrometry, and X-ray crystallography.
- Assay of GPx activity using H(2)O(2) and glutathione (GSH).
- Evaluation of PN scavenging via inhibition of BSA nitration and dihydrorhodamine 123 oxidation.
Main Results:
- Stable spirodiazaselenuranes were synthesized in good yields.
- Structural analysis revealed a distorted trigonal bipyramid selenium core.
- GPx activity was significantly enhanced by electron-donating groups and reduced by electron-withdrawing groups.
- Diaryl selenides effectively scavenged PN, forming spirodiazaselenuranes in situ.
Conclusions:
- Novel spirodiazaselenuranes exhibit promising GPx mimetic and PN scavenging activities.
- Substituent effects on the phenyl ring modulate GPx activity.
- The compounds demonstrate potential as therapeutic agents against oxidative stress.
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