Abstract
Nitroxides are broadly used as molecular probes and labels in biophysics, structural biology, and biomedical research. Resistance of a nitroxide group bearing an unpaired electron to chemical reduction with low-molecular-weight antioxidants and enzymatic systems is of critical importance for these applications. The redox properties of nitroxides are known to depend on the ring size (for cyclic nitroxides) and electronic and steric effects of the substituents. Here, two highly strained nitroxides, 5-(tert-butyl)-5-butyl-2,2-diethyl-3-hydroxypyrrolidin-1-oxyl (4) and 2-(tert-butyl)-2-butyl-5,5-diethyl-3,4-bis(hydroxymethyl)pyrrolidin-1-oxyl (5), were prepared via a reaction of the corresponding 2-tert-butyl-1-pyrroline 1-oxides with butyllithium. Thermal stability and kinetics of reduction of the new nitroxides by ascorbic acid were studied. Nitroxide 5 showed the highest resistance to reduction.
Original language | English |
---|---|
Article number | 845 |
Number of pages | 17 |
Journal | Molecules |
Volume | 25 |
Issue number | 4 |
DOIs | |
Publication status | Published - 14 Feb 2020 |
Keywords
- 1,3-dipolar cycloaddition reaction
- EPR
- Nitrones
- Nitroxides
- Organolithium compounds
- Reduction kinetics
- Spin probes
- NITROXIDE
- reduction kinetics
- nitroxides
- 2-SUBSTITUTED 5,5-DIMETHYL-4-OXO-1-PYRROLINE-1-OXIDES
- PYRROLINE
- organolithium compounds
- spin probes
- ALKOXYAMINES
- REDUCTION
- nitrones
- RADICALS
- PHOTOLYSIS
- DERIVATIVES
- EPR SPECTROSCOPY
- IMIDAZOLIDINE