55482-03-6

Basic information

• Product Name: 2,2-dimethyl-5-hydroxy-1-pyrrolidinyloxy
• Synonyms: 2,2-dimethyl-5-hydroxy-1-pyrrolidinyloxy
• CAS NO: 55482-03-6
• Molecular Formula: C₆H₁₂NO₂
• Molecular Weight: 0
• Mol File: 55482-03-6.mol
• Article Data: 52

Chemical Properties

• Appearance: /
• CAS DataBase Reference: 2,2-dimethyl-5-hydroxy-1-pyrrolidinyloxy(CAS DataBase Reference)
• NIST Chemistry Reference: 2,2-dimethyl-5-hydroxy-1-pyrrolidinyloxy(55482-03-6)
• EPA Substance Registry System: 2,2-dimethyl-5-hydroxy-1-pyrrolidinyloxy(55482-03-6)

Safety Data

• Hazardous Substances Data: 55482-03-6(Hazardous Substances Data)

Usage

InChI:InChI=1/C6H12NO2/c1-6(2)4-3-5(8)7(6)9/h5,8H,3-4H2,1-2H3

Upstream product

• 3317-61-1 5,5-Dimethyl-1-pyrroline N-oxide 
• 67-56-1 methanol 
• 96-26-4 dihydroxyacetone 
• 56-82-6 Glyceraldehyde 
• 141-46-8 Glycolaldehyde 
• 109-73-9 N-butylamine 
• 98-86-2 acetophenone 
• 64-17-5 ethanol 
• 141-53-7 sodium formate 

Relevant articles and documents

Kinetics of spin trapping superoxide, hydroxyl, and aliphatic radicals by cyclic nitrones

Spin trapping coupled with electron paramagnetic resonance (EPR) spectroscopy has surfaced as one of the most specific and reliable methods for identifying free radicals in biological systems. Despite extensive studies focused on the kinetics of radical trapping by cyclic nitrones, the mechanism has not been fully elucidated. Moreover, major controversies still persist even regarding the efficiency and the rate constants of the trapping reaction. The present research used pulse radiolysis for studying the reaction of 5,5-dimethyl-1-pyrroline N-oxide 1 (DMPO) and of the ester-containing derivative, 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide 4, with OH, O2-, CO2 -, C(OH)(CH3)2, CH2OH, and CH3. The results reveal that radical trapping is far more complex then previously realized. Radiation chemical experiments combined with EPR demonstrate that about 30% of OH add to nitrones 1 and 4 at position 2, yielding the corresponding persistent aminoxyls. The remaining OH radicals form transient intermediates that rapidly decay bimolecularly. These transient intermediates react with oxygen with rate constants that are significantly lower than those generally reported for alkyl radicals, which suggests that they are not simple carbon-centered radicals generated as a result of H-abstraction from the methyl or methylene groups of the nitrones. It is also shown that the addition of O2- and various aliphatic radicals to the nitrones is an equilibrium process. The upper limit for the rate constant of the reaction of nitrone 4 with O2 - was 3 M-1 s-1. The rate constant for the reaction of nitrone 1 with O2- was determined to be 170 ± 40 M-1 s-1. This value is significantly higher than those previously determined by following the formation of the corresponding aminoxyl by EPR, which indicates that the yield of the aminoxyl is only a small fraction of the reacting O2-.

THE PRODUCTION OF FREE RADICALS DURING THE AUTOXIDATION OF MONOSACCHARIDES BY BUFFER IONS

The production of free radicals during the autoxidation of simple monosaccharides at 37 degree has been studied by the elctron spin resonance (e. s. r.) technique of spin trapping.In the presence of the spin trap 5,5-dimethyl-1-pyrroline N-oxide (DMPO), monosaccharides undergoing autoxidation produced hydroxyl and 1-hydroxyalkyl radical-derived spin adducts, indicating that hydroxyl and hydroxyalkyl free-radicals are involved in the autoxidation of monosaccharides.The pH profile for the production of free radicals from monosaccharides undergoing autoxidation revealed the formation of both hydroxyl and hydroxyalkyl radicals at relatively high pH, whereas at low pH, only the formation of hydroxyalkyl radicals was observed; the transition between these routes for the production of free radicals occurred at pH 8.0 - 8.5.Glycolaldehyde, glyceraldehyde, dihydroxyacetone, and erythrose are relatively rapidly enolised (to an ene-diol) and autoxidised with the concomitant production of free radicals.Ribose and glucose enolise and autoxidise very slowly without detectable production of free radicals.A comparison of the pH profiles of the rates of enolisation and the pH dependence of the production of free radicals from glyceraldehyde during autoxidation suggests that a change in reaction mechanism occurs at pH 8.2.Below pH 8.2, the rates of enolisation and autoxidaiton increase with increasing pH, with a concomitant increase in the formation of hydroxyalkyl spin-adducts.Above pH 8.2, glyceraldehyde undergoing autoxidation shows a much higher rate of enolisation than of autoxidation and, although the formation of hydroxyalkyl radicals is decreased, the production of hydroxyl radicals is also obsserved.A free-radical mechanism for the autoxidation of monosaccharides is proposed, to account for the pH-dependent characteristics of the production of free radicals and the relationships between the production of free radicals, autoxidation, and enolisation of the monosaccharides.

Probing the surface of transition-metal nanocrystals by chemiluminesence

We propose a simple chemiluminescence (CL) method for investigation of the surface of Co-based nanocrystals (NCs). Using a combination of CL and spin-trap electron paramagnetic resonance techniques, we systematically studied the generation of reactive oxygen species (ROS) at the surface of differently sized CoPt3 spherical NCs and CoPt3/Au nanodumbbells. We have shown that differently sized CoPt3 NCs can promote the formation of ROS and as a result can lead to the oxidation of luminol accompanied by the emission of the light. CL allows monitoring the stability of transition-metal-based NCs against oxidation and dissolution. We found by CL that cobalt ions slowly leach from the surface of CoPt3 NCs even under very mild conditions; however, the amount of the leached cobalt ions does not exceed the maximal concentration of cobalt at the NC surface indicating that only surface atoms can go into solution.

Sensitive determination of triacetone triperoxide explosives using electrogenerated chemiluminescence

Sensitive and selective detection and quantification of high explosive triacetone triperoxide (TATP) with electrogenerated chemiluminescence (ECL) at a glassy carbon electrode in water-acetonitrile solvent mixture were reported. In the presence of ruthenium(II) tris(bipyridine), TATP or hydrogen peroxide derived from TATP via UV irradiation or acid treatment produced ECL emissions upon cathodic potential scanning. Interference from hydrogen peroxide on TATP detection was eliminated by pretreatment of the analyte with catalase enzyme. Selective detection of TATP from hexamethylene triperoxide diamine (HMTD, another common peroxide-based explosive) was realized by comparing ECL responses obtained from the anodic and the cathodic potential scanning; TATP produced ECL upon cathodic potential scanning only, whereas HMTD produced ECL upon both cathodic and anodic potential scanning. The hydroxyl radical formed after the electrochemical reduction of TATP was believed to be the key intermediate for ECL production, and its stability was strongly dependent on the solution composition, which was verified with electron paramagnetic resonance spectroscopy. A detection limit of 2.5 μM TATP was obtained from direct electrochemical reduction of the explosive or hydrogen peroxide derived from TATP in 70/30% (v/v) water-acetonitrile solutions, which was ～400 times lower than that reported previously based on liquid chromatography separation and Fourier transform infrared detection.

Enhanced peroxidase-like activity of porphyrin functionalized ZnFe2O4 hollow nanospheres for rapid detection of H2O2 and glucose

Using a simple one-pot solvothermal method, binary metal oxide, magnetic and hollow ZnFe2O4 nanospheres functionalized with 5,10,15,20-tetrakis(4-carboxylphenyl)-porphyrin (Por-ZnFe2O4 HSs) were prepared and subsequently applied as a substitute for natural peroxidase. The Por-ZnFe2O4 HSs were characterized using powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). In comparison with bare ZnFe2O4 HSs, Por-ZnFe2O4 HSs exhibit enhanced intrinsic peroxidase-like activity. They demonstrate a fast colorimetric response to H2O2 with a detection limit as low as 0.86 μM. The catalytic mechanism of the system was proved to be a hydroxyl radical mechanism using electron spin resonance (ESR). By combining the Por-ZnFe2O4 HSs-catalyzed reaction and the enzymatic oxidation of glucose with glucose oxidase, a colorimetric platform for glucose detection was established. The Por-ZnFe2O4 HSs/glucose oxidase (GOx)/TMB system shows a good response toward glucose with a detection limit of 5.5 μM. Therefore, such nanocomposites have promising applications in biomimetic catalysis and environmental monitoring.

Chitosan as an antioxidant alternative to sulphites in oenology: EPR investigation of inhibitory mechanisms

The efficacy against oxidative degradation in model and sulphite-free white wines of two commercial, insoluble chitosans (one being approved for winemaking) were investigated by electron paramagnetic resonance (EPR). Both compounds at various doses significantly inhibited the formation of α-(4-pyridyl-1-oxide)-N-t-butylnitrone (4-POBN)-1-hydroxyethyl adducts under normal wine storage conditions. Pre-incubation with 2 g/L chitosan followed by filtration had a better effect than adding 50 mg/L sulphur dioxide to the experimental Chardonnay wine on the release of 4-POBN adducts after 6 days of incubation with 100 μM iron(II). In a relevant photooxidative system acetaldehyde formation was significantly reduced after 6 days of incubation. Parallel EPR tests were performed to assess the importance of metal chelation (iron and copper) versus direct scavenging of hydroxyl radicals on the effect of chitosan. The present data support the potentiality of using biocompatible chitosan as a healthier complement and/or alternative to sulphur dioxide against white wine oxidative spoilage.

Imaging of Hydroxyl-Radical Generation Using Dynamic Nuclear Polarization-Magnetic Resonance Imaging and a Spin-Trapping Agent

Reactive oxygen species (ROS) play an important role in cell metabolism, but they can cause oxidative damage to biomolecules. Among ROS, the hydroxyl radical (·OH) is one of the most reactive molecules in biological systems because of its high reaction rate constant. Therefore, imaging of ·OH could be useful for evaluation of the redox mechanism and diagnosis of oxidative diseases. In vivo dynamic nuclear polarization-magnetic resonance imaging (DNP-MRI) is a noninvasive imaging method to obtain spatiotemporal information about free radicals with MRI anatomical resolution. In this study, we investigated the visualization of hydroxyl radicals generated from the Fenton reaction by combining DNP-MRI with a spin-trapping agent (DMPO: 5,5-dimethyl-1-pyrroline N-oxide) for ·OH. Additionally, we demonstrated the radical-scavenging effect using four thiol-related reagents by DNP-MRI. We demonstrated that DNP enhancement could be induced by the DMPO-OH radical using the DNP-MRI/spin-trapping method and visualized ·OH generation for the first time. Maximum DNP enhancement was observed at an electron paramagnetic resonance irradiation frequency of 474.5 MHz. Furthermore, the radical-scavenging effect was simultaneously evaluated by the decrease in the DNP image value of DMPO-OH. An advantage of our methods is that they simultaneously investigate compound activity and the radical-scavenging effect.

Carbohydrate recognition and photodegradation by an anthracene-Kemp's acid hybrid

Selective recognition and photodegradation of a monosaccharide, octyl β-d-glucopyranoside, was achieved without any additives under neutral conditions using an anthracene-Kemp's acid hybrid and long-wavelength UV irradiation.

Complexation of the sunscreen agent, phenylbenzimidazole sulphonic acid with cyclodextrins: Effect on stability and photo-induced free radical formation

The interaction between the sunscreen agent, phenylbenzimidazole sulphonic acid (PBSA) and hydrophilic α-, β-, and γ-cyclodextrin derivatives was investigated under acidic conditions (pH 4.0) by phase-solubility analysis. Among the available cyclodextrins, hydroxypropyl-β-cyclodextrin (HP-β-CD) and random methyl-β- cyclodextrin (RM-β-CD) had the greatest solubilizing activity. The complexation of the sunscreen agent with HP-β-CD and RM-β-CD was confirmed by nuclear magnetic resonance spectroscopy. Solid-phase characterization of the PBSA/cyclodextrin systems by X-ray diffractometry defined the most appropriate method (co-evaporation) and cyclodextrin concentration (10-fold molar excess) for the preparation of a stable complexed form of PBSA. Long-term stability studies demonstrated that the decrease of the sunscreen level in emulsion preparations (pH 4.0) was almost completely suppressed by HP-β-CD, RM-β-CD being less effective. Moreover, the irradiation-induced decomposition of PBSA in the emulsion vehicle was markedly reduced by complexation with HP-β-CD (the extent of degradation was 3.9% for the complex compared to 9.1% for uncomplexed PBSA), whereas RM-β-CD had no significant influence. In addition, electron paramagnetic resonance (EPR) spin-trapping studies showed that the inclusion of the sunscreen agent into the HP-β-CD cavity completely inhibited the formation of free-radicals generated by PBSA on exposure to simulated sunlight, thereby suppressing its photosensitising potential.

Hydroxyl radical generation by dissociation of water molecules during 1.65?MHz frequency ultrasound irradiation under aerobic conditions

The dissociation of water molecules by ultrasound irradiation under aerobic conditions was demonstrated experimentally. To be able to detect the dissociation of water molecules, we performed the ultrasound irradiation of 17O-labelled water (H217O) under aerobic conditions. The hydroxyl and hydrogen radicals generated during the ultrasound irradiation process were trapped with 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), and electron spin resonance (ESR) spectroscopy was performed on the DMPO spin adducts. In the ESR spectrum, a 15-line signal attributable to the trapping of the hydroxyl radicals containing 17O (17OH radicals) by DMPO together with a 4-line signal attributable to the trapping of the hydroxyl radicals containing 16O (16OH radicals) by DMPO were observed. The generation of 17OH radicals indicated that H217O was dissociated by the sonolysis process under aerobic conditions. On the other hand, the ESR signal attributable to the trapping of hydrogen radicals by DMPO was not observed, suggesting that hydrogen radicals were not generated during the dissociation of water molecules.

Superoxide anion radical generation in the NaOH/H2O 2/Fe(III) system: A spin trapping ESR study

Formation of free radical intermediates in a NaOH/H2O 2/Fe(III) system has been studied by ESR spectroscopy in the presence of the spin trap 5,5-dimethy-1-pyrroline N-oxide (DMPO). DMPO/O 2?- and DMPO/?OH signals were simultaneously detected in this system, but only the DMPO/?OH signal could be observed in the absence of Fe(III). Effects of pH values and Fe(III) concentrations on the ESR signal intensities were investigated in detail. Formation of DMPO/O2?- adduct was inhibited by the addition of superoxide dismutase (SOD), catalase or nitro blue tetrazolium (NBT), and by chelating the Fe(III) with some chelators, including ethylenediaminetetraacetic acid (EDTA), diethylenetriaminepentaacetic acid (DTPA), and desferrioxamine (DFO). Deoxygenation from the NaOH/H 2O2/Fe(III) mixture had a slight effect on the formation of DMPOTO2?-. DMPO/O2?- signal was also detected from the NaOH/H2O2/Fe(II) mixture, but it can be totally suppressed under anaerobic conditions. Considering the hydrolysis of Fe(III) into polymerization iron species with oxide phases in the alkaline medium, Fe2O3 was directly suspended into a mixture of NaOH/H2O2 for comparison. Fortunately, the presence of Fe2O3 suspension was found to be of benefit to the production of DMPO/O2?-. Influence of aging time of hydrolytic iron species on the superoxide anion radical generation was also studied. These results suggest that the generation of O2?- from the NaOH/H2O 2/Fe(III) system was probably caused by the heterogeneous surface catalysis initiated by hydrolytic iron species. Copyright

Comparison of cardioprotective efficacy of two thromboxane A2 receptor antagonists

The purpose of the current study was to compare the efficacy of two structurally unrelated thromboxane A2 (TXA2) receptor antagonists, KT2-962 and daltroban (BM 13.505), in a dog model of myocardial ischemia/reperfusion injury. Pentobarbital-anesthetized dogs were subjected to left circumflex coronary artery occlusion for 90 minutes followed by 5 hours of reperfusion. Vehicle, KT2-962 (10 mg/kg), or daltroban (10 mg/kg) were administered as intravenous boluses 10 minutes before coronary occlusion. Systemic hemodynamics were measured throughout the experiments and regional myocardial blood flow was measured by the radioactive microsphere technique. At the end of the reperfusion period, myocardial infarct size was quantified by staining with triphenyltetrazolium chloride. Neither KT2-962 nor daltroban significantly altered heart rate, mean arterial blood pressure, or regional myocardial blood flow. The content of myeloperoxidase activity in the ischemic/reperfused tissue, an index of neutrophil infiltration, was not significantly different among the three treatment groups. However, administration of KT2-962, but not daltroban, significantly reduced the incidence of ventricular fibrillation during the ischemic period and significantly reduced myocardial infarct size expressed as a percentage of the risk region (approximately 40%). Subsequent in-vitro assays using electron spin resonance spectroscopy demonstrated that KT2-962 inhibited the formation of hydroxyl radicals, whereas daltroban had no effect. These results suggest that the beneficial effects of KT2-962 may be due to its direct free radical scavenging properties rather than its ability to block TXA2 receptors.