Sulfoxydes et sulfones hétérobicycliques dérivés de l'α-thioglycérol. 2,8-Dioxa-6-oxo-6-thiabicyclo[3.2.1]octanes et 2,8-dioxa-6,6′-dioxo-6-thiabicyclo[3.2.1]octanes

1983 ◽  
Vol 61 (9) ◽  
pp. 2095-2102 ◽  
Author(s):  
Pierre Calinaud ◽  
Jacques Gelas
Keyword(s):  
Chemical Properties ◽  
Oxidation Reactions ◽  
Tert Butyl ◽  
And Chemical Properties

The oxidation reactions of heterobicyclic sulfides derived from α-thioglycerol (alkyl-2,8-dioxa-6-thiabicyclo[3.2.1]octanes), leading to sulfoxides and the corresponding sulfones, have been studied. The stereochemistry of the oxidation as a function of the reagent used (H2O2, meta-chloroperbenzoic acid, and tert-butyl hypochlorite) has been examined. Structural assignments of the sulfoxides arise from the spectroscopic and chemical properties of these compounds. [Journal translation]

ChemInform Abstract: 2-TRIETHYLSILYL- AND 2-TRIETHYLGERMYL-1,3-DI-TERT-BUTYL-1,3,2-DIAZAPHOSPHORINANES: SYNTHESIS, STRUCTURE AND CHEMICAL PROPERTIES

1985 ◽  
Vol 16 (16) ◽  
Author(s):  
E. E. NIFANT'EV ◽  
N. S. VYAZANKIN ◽  
S. F. SOROKINA ◽  
L. A. VOROB'EVA ◽  
O. A. VYAZANKINA ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Tert Butyl ◽  
And Chemical Properties

scholarly journals The oxidation of reduced nicotinamide nucleotides by hydrogen peroxide in the presence of lactoperoxidase and thiocyanate, iodide or bromide

1970 ◽  
Vol 117 (4) ◽  
pp. 791-797 ◽  
Author(s):  
D. McC. Hogg ◽  
G. R. Jago
Keyword(s):  
Hydrogen Peroxide ◽  
Oxidation Product ◽  
Chemical Properties ◽  
Oxidation Reactions ◽  
Significant Extent ◽  
And Chemical Properties

Lactoperoxidase (EC 1.11.1.7) catalysed the oxidation of NADH by hydrogen peroxide in the presence of either thiocyanate, iodide or bromide. In the presence of thiocyanate, net oxidation of thiocyanate occurred simultaneously with the oxidation of NADH, but in the presence of iodide or bromide, only the oxidation of NADH occurred to a significant extent. In the presence of thiocyanate or bromide, NADH was oxidized to NAD+ but in the presence of iodide, an oxidation product with spectral and chemical properties distinct from NAD+ was formed. Thiocyanate, iodide and bromide appeared to function in the oxidation of NADH by themselves being oxidized to products which in turn oxidized NADH, rather than by activating the enzyme. Iodine, which oxidized NADH non-enzymically, appeared to be an intermediate in the oxidation of NADH in the presence of iodide. NADPH was oxidized similarly under the same conditions. An assessment was made of the rates of these oxidation reactions, together with the rates of other lactoperoxidase-catalysed reactions, at physiological concentrations of thiocyanate, iodide and bromide. The results indicated that in milk and saliva the oxidation of thiocyanate to a bacterial inhibitor was likely to predominate over the oxidation of NADH.

scholarly journals Synthesis and structural features of 5-(4-(tert-butyl) phenyl)-4-((R)amino)-4H-1,2,4-triazole-3-thiols

2018 ◽  
pp. 60-65
Author(s):  
I. I. Aksyonova-Seliuk ◽  
O. I. Panasenko ◽  
E. G. Knysh
Keyword(s):  
Chemical Structure ◽  
Chemical Properties ◽  
Biologically Active ◽  
Physical And Chemical Properties ◽  
Tert Butyl ◽  
New Compounds ◽  
Physical And Chemical ◽  
Derivatives Of ◽  
Active Substances ◽  
And Chemical Properties

Chemistry of heterocyclic compounds is one of the most popular sector in organic chemistry. Scientists allocate among them a class of derivatives of 1,2,4-triazole. This class of compounds attracts attention his broad spectrum of biological activity. There are antiviral, anti-inflammatory, anti-tubercular, antimicrobial, antioxidant, actoprotective, anti-cancer and other activities. The derivatives of 1,2,4-triazole have one more important advantage. It is low toxicity. This properties do this class of derivatives promising for researches their chemical structure and biological activity and purposeful search of biologically active substances. The purpose of the work is synthesis of 5-(4-(tert-butyl)phenyl)-4-((R)amino)-4H-1,2,4-triazoles-3-thiols from appropriate ylidene derivatives of 4-amino-5-(4 (tert-butyl)phenyl)-4H-1,2,4-triazoles-3-thiol and research of their physical and chemical properties. The objects of research were 10 new compounds, derivatives of 4-amino-5-(4-(tert-butyl)phenyl)-4H-1,2,4-triazoles-3-thiol. These compounds are the crystal substances which are odorless, insoluble in water and soluble in organic solvents. Investigation of the physical and chemical properties of this compounds was carried out according to the methods listed in the State Pharmacopoeia of Ukraine. The melting temperature of synthesized compounds was determined by device OptiMelt Stanford Research Systems MPA100. The structure of the compound was confirmed by 1H-NMR spectroscopy (Mercury 400) and gas chromatography-mass spectrometry (Agilent 1260 Infinity HPLC). 10 new compounds, derivatives of 4-amino-5-(4-(tert-butyl)phenyl)-4H-1,2,4-triazoles-3-thiol, were synthesized in a study. The chemical structure of the new compounds was confirmed by modern instrumental methods of analysis. Results of the done work can be use in the future search of biologically active substances.

Statistical criteria of stellar population types

1966 ◽  
Vol 24 ◽  
pp. 101-110
Author(s):  
W. Iwanowska
Keyword(s):  
Stellar Population ◽  
Chemical Properties ◽  
Spectrophotometric Study ◽  
Physical And Chemical Properties ◽  
Population Type ◽  
The Galaxy ◽  
Distribution Parameters ◽  
Physical And Chemical ◽  
Statistical Criteria ◽  
And Chemical Properties

In connection with the spectrophotometric study of population-type characteristics of various kinds of stars, a statistical analysis of kinematical and distribution parameters of the same stars is performed at the Toruń Observatory. This has a twofold purpose: first, to provide a practical guide in selecting stars for observing programmes, second, to contribute to the understanding of relations existing between the physical and chemical properties of stars and their kinematics and distribution in the Galaxy.

The microstructure of a TiB2/Ti-47 Al composite material

1989 ◽  
Vol 47 ◽  
pp. 674-675
Author(s):  
O. Popoola ◽  
A.H. Heuer ◽  
P. Pirouz
Keyword(s):  
Composite Material ◽  
Ion Beam ◽  
Chemical Properties ◽  
Intermetallic Alloys ◽  
Transmission Electron ◽  
Diamond Polishing ◽  
Al Composite ◽  
The Matrix ◽  
Argon Ion ◽  
And Chemical Properties

The addition of fibres or particles (TiB2, SiC etc.) into TiAl intermetallic alloys could increase their toughness without compromising their good high temperature mechanical and chemical properties. This paper briefly discribes the microstructure developed by a TiAl/TiB2 composite material fabricated with the XD™ process and forged at 960°C.The specimens for transmission electron microscopy (TEM) were prepared in the usual way (i.e. diamond polishing and argon ion beam thinning) and examined on a JEOL 4000EX for microstucture and on a Philips 400T equipped with a SiLi detector for microanalyses.The matrix was predominantly γ (TiAl with L10 structure) and α2(TisAl with DO 19 structure) phases with various morphologies shown in figure 1.

Tailoring microstructures of materials through biomimetics

1993 ◽  
Vol 51 ◽  
pp. 500-501
Author(s):  
Mehmet Sarikaya ◽  
Ilhan A. Aksay
Keyword(s):  
Chemical Properties ◽  
Design And Synthesis ◽  
Structure Sensitive ◽  
Macro Scale ◽  
Methods Of Synthesis ◽  
Successive Level ◽  
Engineering Materials ◽  
Physical And Chemical ◽  
And Chemical Properties ◽  
Synthesis Of Materials

Biomimetics involves investigation of structure, function, and methods of synthesis of biological composite materials. The goal is to apply this information to the design and synthesis of materials for engineering applications.Properties of engineering materials are structure sensitive through the whole spectrum of dimensions from nanometer to macro scale. The goal in designing and processing of technological materials, therefore, is to control microstructural evolution at each of these dimensions so as to achieve predictable physical and chemical properties. Control at each successive level of dimension, however, is a major challenge as is the retention of integrity between successive levels. Engineering materials are rarely fabricated to achieve more than a few of the desired properties and the synthesis techniques usually involve high temperature or low pressure conditions that are energy inefficient and environmentally damaging.In contrast to human-made materials, organisms synthesize composites whose intricate structures are more controlled at each scale and hierarchical order.

On some energetic and chemical properties of the calcite surface

1976 ◽  
Vol 73 ◽  
pp. 351-355 ◽  
Author(s):  
Gilles Goujon ◽  
Boyan Mutaftschiev
Keyword(s):  
Chemical Properties ◽  
And Chemical Properties
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