Highly stereocontrolled syntheses of 2,3-disubstituted 1,4-butyrolactones using ionic and free radical reactions

1993 ◽  
Vol 71 (9) ◽  
pp. 1407-1411 ◽  
Author(s):  
Stephen Hanessian ◽  
Benoit Vanasse ◽  
Hua Yang ◽  
Marco Alpegiani
Keyword(s):  
Free Radical ◽  
Radical Reactions ◽  
Substitution Reactions ◽  
Free Radical Reactions ◽  
Free Radical Processes ◽  
Radical Processes

N-Substituted 3-amino-1,4-butyrolactones undergo highly stereocontrolled substitution reactions via anionic and free radical processes.

Concluding remarks: a prospective view of active oxygen in medicine

1982 ◽  
Vol 60 (11) ◽  
pp. 1425-1429 ◽  
Author(s):  
A. Petkau
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Free Radical ◽  
Active Oxygen ◽  
Radical Reactions ◽  
Free Radical Reactions ◽  
Free Radical Processes ◽  
Rational Therapy ◽  
The Central Nervous System ◽  
Radical Processes

Factors are identified that influence the initiation, propagation, and efficiency of free-radical processes, or that ameliorate or mask them. Major biochemical disruptions of the ischemic myocardium or the central nervous system are cited for their underlying free-radical reactions. Encouraging attempts at rational therapy of disease having a free-radical component are referenced.

EFFECT OF PLAN TEXTRACTS ON THE LEVEL OF FREE-RADICAL PROCESSES IN HUMAN CELLS

2021 ◽  
Vol 55 (4) ◽  
pp. 67-72
Author(s):  
A. Alkhaddour ◽  
◽  
E.V. Mashkina ◽  
Keyword(s):  
Free Radical ◽  
Punica Granatum ◽  
Human Cells ◽  
Radical Reactions ◽  
Flash Intensity ◽  
Free Radical Reactions ◽  
Specific Pcr ◽  
Allele Specific ◽  
Peripheral Leukocytes ◽  
Radical Processes

We evaluated the effects of extracts from the pomegranate (Punica granatum), vine (Vitis vinifera) seeds and garlic (Allium sativum) on free-radical reactions in human cells in relation to SNPs in the SOD2and СAT genes. The object was human peripheral leukocytes cultured in the presence of extracts from pomegranate (1.2; 2.4 %), garlic (0.5; 1.2 %) and vine seeds (1.2; 2.4 %). Intensity of free-radical reactions was assessed by a fast flash and flashlight sum of the luminol-dependent chemiluminescence (LDCL). Alleles of SOD2and СAT were analyzed using allele-specific PCR. The results showed that the pomegranate extract decreases LDCL intensity reliably in comparison with the control. Extracts of the garlic (1.2 %) and vine seeds (1.2 %) increase LDCL intensity. Correlation was established between the genotype determined by polymorphism of SOD2 gene Ala16Val (rs4880) and fast flash intensity during human cell cultivation with the extract of vine seeds (1.2 %).

Adaptogenic correction of free radical brain damage in subchronic exposure to sodium fl uoride

2020 ◽  
pp. 381-386
Author(s):  
A. G. Zhukova ◽  
L. G. Gorokhova ◽  
A. S. Kazitskaya ◽  
T. K. Yadykina ◽  
N. N. Mikhailova ◽  
...  
Keyword(s):  
Cerebral Cortex ◽  
Free Radical ◽  
Brain Tissue ◽  
Free Radical Oxidation ◽  
Radical Oxidation ◽  
Free Radical Processes ◽  
Subchronic Exposure ◽  
Antioxidant Defense Enzymes ◽  
Radical Processes ◽  
Complex Drug

Introduction. Fluorine compounds in small doses, but with prolonged exposure, cause various disorders in organs at the cellular and molecular levels. Activation of free-radical processes plays an important role in the damaging eff ect of fl uorides. Th erefore, one of the most eff ective ways to limit fl uorine-induced damage is to directly aff ect free-radical processes using herbal preparations with antioxidant properties.The aim of the study is to study the eff ect of a dihydroquercetin-based drug on the activity of free radical processes in brain tissue under subchronic exposure to sodium fl uoride (NaF).Materials and methods. Th e work was performed on white male laboratory rats weighing 200-250 g. Th e rats were divided into 3 groups: 1 — control; 2 — rats with chronic exposure to sodium fl uoride (NaF) for 9 weeks; 3 — rats receiving a NAF solution with simultaneous administration of a complex drug based on dihydroquercetin at a dose of 3 mg/kg in 1% starch gel for 3, 6 and 9 weeks. The activity of free radical oxidation and antioxidant defense enzymes — superoxide dismutase (SOD) and catalase-was determined in the cerebral cortex. Th e level of expression of hypoxia-induced transcription factor HIF — 1A and inducible forms of proteins HSP72 and HSP32 were determined in the cytosolic fraction of brain tissue.Results. In the early stages of subchronic fl uoride exposure (1-3 weeks), the expression of protective proteins HIF-1α, HSP72, HSP32 and catalase was shown in the rat cortex, as a result of which the activity of free-radical processes was maintained at the control level. An increase in the timing of fl uoride intake to 9 weeks led to a decrease in antioxidant protection and signifi cant activation of free radical oxidation in brain tissue. Daily administration of a complex drug with dihydroquercetin for 3, 6 and 9 weeks to rats with subchronic fl uoride exposure led to a decrease in the severity of pro- and antioxidant balance disorders in the cerebral cortex. At the same time, the greatest protective eff ect of dihydroquercetin with fl uoride exposure was manifested by the 9th week of its administration.Conclusions. When subchronic intake of fl uorides in the body, the drug based on dihydroquercetin has a neuroprotective eff ect, which is manifested by an increase in the activity of antioxidant enzymes of fr ee radical oxidation and catalase and the resistance of the cortex to induced fr ee radical oxidation.

The initial reaction mechanism and thermal sensitivity of a fluoropolymer-containing energetic molecular system: the coupling effect of interfacial interactions and free radical reactions

CrystEngComm ◽  
2021 ◽  
Vol 23 (16) ◽  
pp. 3006-3014
Author(s):  
Wen Qian
Keyword(s):  
Free Radical ◽  
Coupling Effect ◽  
Molecular System ◽  
Thermal Sensitivity ◽  
Radical Reactions ◽  
Initial Reaction ◽  
Interfacial Interactions ◽  
Free Radical Reactions ◽  
Molecular Systems ◽  
Reactive Molecular Dynamics

A strategy combining classic and reactive molecular dynamics is applied to find the coupling effect of interfacial interactions and free radical reactions during the initial thermal decomposition of fluoropolymer-containing molecular systems.

Further studies on free-radical pathology in the major central nervous system disorders: effect of very high doses of methylprednisolone on the functional outcome, morphology, and chemistry of experimental spinal cord impact injury

1982 ◽  
Vol 60 (11) ◽  
pp. 1415-1424 ◽  
Author(s):  
H. B. Demopoulos ◽  
E. S. Flamm ◽  
M. L. Seligman ◽  
D. D. Pietronigro ◽  
J. Tomasula ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Central Nervous System ◽  
Nervous System ◽  
Free Radical ◽  
Tissue Injury ◽  
Functional Restoration ◽  
Radical Reactions ◽  
Free Radical Reactions ◽  
Cord Injury

The hypothesis that pathologic free-radical reactions are initiated and catalyzed in the major central nervous system (CNS) disorders has been further supported by the current acute spinal cord injury work that has demonstrated the appearance of specific, cholesterol free-radical oxidation products. The significance of these products is suggested by the fact that: (i) they increase with time after injury; (ii) their production is curtailed with a steroidal antioxidant; (iii) high antioxidant doses of the steroidal antioxidant which curtail the development of free-radical product prevent tissue degeneration and permit functional restoration. The role of pathologic free-radical reactions is also inferred from the loss of ascorbic acid, a principal CNS antioxidant, and of extractable cholesterol. These losses are also prevented by the steroidal antioxidant. This model system is among others in the CNS which offer distinctive opportunities to study, in vivo, the onset and progression of membrane damaging free-radical reactions within well-defined parameters of time, extent of tissue injury, correlation with changes in membrane enzymes, and correlation with readily measurable in vivo functions.

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