Redox reactions in acetic anhydride

1975 ◽  
Vol 28 (5) ◽  
pp. 991 ◽  
Author(s):  
KC Malhotra ◽  
DS Katoch
Keyword(s):  
Acetic Anhydride ◽  
Redox Reactions ◽  
Reducing Agents ◽  
Iodine Monochloride ◽  
Nitrosyl Chloride ◽  
Oxidizing Agents ◽  
New Compounds

Redox reactions in acetic anhydride have been followed both conductometrically and visually. Chlorine, bromine, iodine, iodine monochloride and nitrosyl chloride have been used as oxidizing agents and phosphorus(III), arsenic(III) and antimony(III) compounds as reducing agents. Some new compounds have been isolated and characterized.

Three new staphylonuclear chloromolybdates : K6Mo3Cl12, (NH4)7Mo3Cl13,H2O, and Cs6Mo4Cl16

1965 ◽  
Vol 18 (3) ◽  
pp. 271 ◽  
Author(s):  
IR Anderson ◽  
JC Sheldon
Keyword(s):  
Solid State ◽  
Hydrochloric Acid ◽  
Absorption Spectra ◽  
Oxidation State ◽  
Chlorine Atom ◽  
Reducing Agents ◽  
Ammonium Salts ◽  
Chlorine Atoms ◽  
Regular Triangle ◽  
New Compounds

The new compounds, K6Mo3IICl12; (NH4)7Mo3IICl13.H2O; and Cs6Mo4Cl16 (containing molybdenum in oxidation state +2.5) have been precipitated by the appropriate cation from solutions of molybdenum(II) acetate in 12M hydrochloric acid. The absorption spectra of potassium and ammonium salts are similar in the solid state and solution. Since the compounds are strong reducing agents and short-lived in solution, their formulation as a staphylonuclear (i.e. metal-clustered) trimer or tetramer rests on their diamagnetism, stoicheiometry, and spectral similarities. It is proposed that the chloromolybdates adopt entirely novel, compact polymers by stacking the chlorine atoms into "close packed" layers. The Mo3Cl13 group consists of two layers of chlorine atoms (seven and six) generating three octahedral locations for the molybdenum atoms at the corners of a regular triangle. The Mo3Cl12 group is similar but deficient in one chlorine atom. The Mo4Cl16 group is related to Mo3Cl13 and consists of three layers of chlorine atoms (seven, six, and three) providing four octahedral locations for the molybdenum atoms at the corners of a tetrahedron.

scholarly journals Formation of Acetoxyl Radical in the Reactions of Acetic Anhydride with Reducing Agents

1963 ◽  
Vol 84 (12) ◽  
pp. 984-986
Author(s):  
Iwao TABUSHTI ◽  
Toru IDE ◽  
Ryohei ODA
Keyword(s):  
Acetic Anhydride ◽  
Reducing Agents

scholarly journals PROTEOLYTIC ENZYMES

1946 ◽  
Vol 29 (4) ◽  
pp. 219-247 ◽  
Author(s):  
David Grob
Keyword(s):  
Proteolytic Enzymes ◽  
Reducing Agents ◽  
Sulfhydryl Groups ◽  
Ion Concentration ◽  
Hydrogen Ion Concentration ◽  
Oxidizing Agents ◽  
Neutral Ph ◽  
Oxidation Reduction ◽  
Antiproteolytic Activity ◽  
Sulfhydryl Compounds

1. The literature on conditions affecting the activity of proteolytic enzymes has been reviewed. 2. Experimental data on the control of the activity of trypsin, leucoprotease, papain, serum antiprotease, leucopeptidase, and pancreatic peptidase have been presented. These data indicate that: (a) The polymorphonuclearleucocytes of the cat contain abundant proteinase and peptidase active at neutral pH; those of the rabbit lack proteinase active at neutral pH. (b) Reducing agents, including several biologically important thiol-sulfhydryl compounds and ascorbic acid, inhibit the activity of leucoprotease and trypsin. For each reductant the degree of inhibition is proportional to the reducing capacity of the medium. (c) p-Aminobenzoic acid, sulfonamides (especially sulfathiazole), and many diphenyl sulfones inhibit the activity of leucoprotease. (d) Serum, plasma, several heavy metals, ammonium salts, asparagine, thiourea, heparin, glutamic acid, tyrothricin, calcium chloride, and bile salts and bile acids also inhibit the activity of leucoprotease, and in most cases of trypsin too. (e) Preparations of tryptic digests of proteins, and egg white trypsin inhibitor, inhibit trypsin to a much greater degree than leucoprotease. (f) Mild oxidizing agents increase the activity of leucoprotease and trypsin. (g) Oxidizing agents and some inhibitors of sulfhydryl groups inhibit the antiproteolytic activity of the serum. It is suggested that serum antiprotease may consist (chiefly) of reducing agents, including thiol-sulfhydryl peptides which exert their antiproteolytic activity by virtue of the presence of sulfhydryl groups. (h) The antiproteolytic activity of the serum is progressively weakened by exposure to a hydrogen ion concentration below pH 6.5 or above pH 9.7. Because of this the pH optima of leucoprotease and trypsin are shifted in the presence of serum from pH of 7 and 8 to pH of 6 to 6.5, and the range of activity of these enzymes is slightly widened, in both acid and alkaline reactions. (i) Reducing agents increase the activity of leucopeptidase and pancreatic peptidase. Serum, sulfathiazole, and thiourea have little or no effect. 3. The significance of the oxidation-reduction system in the control of the activity of leucoprotease, trypsin, serum antiprotease, leucopeptidase, and pancreatic peptidase has been emphasized.

scholarly journals Synthesis, characterization and Cytotoxicity Evaluation of New Compounds from Oxazol-5(4H)-ones and Oxazoles Class Containing 4-(4-Bromophenylsulfonyl)phenyl Moiety

2019 ◽  
Vol 70 (4) ◽  
pp. 1099-1107
Author(s):  
Theodora-Venera Apostol ◽  
Stefania-Felicia Barbuceanu ◽  
Octavian Tudorel Olaru ◽  
Constantin Draghici ◽  
Gabriel Saramet ◽  
...  
Keyword(s):  
Acetic Anhydride ◽  
Phosphorus Oxychloride ◽  
Spectral Studies ◽  
Ethyl Chloroformate ◽  
Anhydrous Aluminum Chloride ◽  
1H And 13C Nmr ◽  
Ft Ir ◽  
Concentrated Sulfuric Acid ◽  
New Compounds

Steiger N-acylation of a-alanine with 4-(4-bromophenylsulfonyl)benzoyl chloride led to 2-[4-(4-bromophenylsulfonyl)benzamido]propanoic acid. This compound underwent intramolecular cyclization in the presence of N-methylmorpholine and ethyl chloroformate or acetic anhydride to the corresponding saturated azlactone. Then acylaminoacylation of dry aromatic hydrocarbons with 2-[4-(4-bromophenylsulfonyl)phenyl]-4-methyloxazol-5(4H)-one or 2-[4-(4-bromophenylsulfonyl) benzamido ]propanoyl chloride in the presence of anhydrous aluminum chloride led to corresponding a-acylamino ketones. These new intermediates were heterocyclized under the action of phosphorus oxychloride or concentrated sulfuric acid in the presence of acetic anhydride to the corresponding oxazoles. The newly synthesized compounds were characterized by spectral studies (FT-IR, UV-Vis, MS, 1H- and 13C-NMR) and elemental analysis. The purity of the new compounds was evaluated by RP-HPLC. The experimental research regarding to the in vitro cytotoxic activity of the new compounds were performed using Daphnia magna bioassay.

scholarly journals Synthesis, characterization and Cytotoxicity Evaluation of New Compounds from Oxazol-5(4H)-Ones and 1,2,4-Triazin-6(5H)-Ones Classes

2019 ◽  
Vol 70 (11) ◽  
pp. 3769-3774
Author(s):  
Elena Valentina Rosca ◽  
Theodora Venera Apostol ◽  
Constantin Draghici ◽  
Octavian Tudorel Olaru ◽  
Laura Ileana Socea ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Elemental Analysis ◽  
13C Nmr ◽  
Heterocyclic Compounds ◽  
Sodium Acetate ◽  
Artemia Salina ◽  
Ft Ir ◽  
New Compounds ◽  
Acetic Acids

This paper presents the synthesis of new heterocyclic compounds from oxazoles and triazinones classes. Some 2-(4-(4-X-phenylsulfonyl)benzamido)acetic acids were condensed with 4-iodobenzaldehyde in presence of acetic anhydride and sodium acetate, when the new corresponding unsaturated oxazol-5(4H)-one were obtained. Through the reaction of these oxazol-5(4H)-ones with phenylhydrazine, in presence of the acetic acid and sodium acetate, the new heterocyclic compounds from 1,2,4-triazin-6(5H)-ones class were obtained. The structures of synthesized compounds have been confirmed by spectral methods (FT-IR, 1H-NMR, 13C-NMR and MS) and elemental analysis. The cytotoxicity of the compounds was evaluated using the Daphnia magna and Artemia salina bioassays.

scholarly journals Synthesis, characterization and Cytotoxicity Evaluation of New Compounds from Oxazol-5(4H)-Ones and 1,2,4-Triazin-6(5H)-Ones Classes

2019 ◽  
Vol 70 (11) ◽  
pp. 3769-3774
Author(s):  
Elena Valentina Rosca ◽  
Theodora Venera Apostol ◽  
Constantin Draghici ◽  
Octavian Tudorel Olaru ◽  
Laura Ileana Socea ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Acetic Anhydride ◽  
Elemental Analysis ◽  
13C Nmr ◽  
Heterocyclic Compounds ◽  
Sodium Acetate ◽  
Artemia Salina ◽  
Ft Ir ◽  
New Compounds ◽  
Acetic Acids

This paper presents the synthesis of new heterocyclic compounds from oxazoles and triazinones classes. Some 2-(4-(4-X-phenylsulfonyl)benzamido)acetic acids were condensed with 4-iodobenzaldehyde in presence of acetic anhydride and sodium acetate, when the new corresponding unsaturated oxazol-5(4H)-one were obtained. Through the reaction of these oxazol-5(4H)-ones with phenylhydrazine, in presence of the acetic acid and sodium acetate, the new heterocyclic compounds from 1,2,4-triazin-6(5H)-ones class were obtained. The structures of synthesized compounds have been confirmed by spectral methods (FT-IR, 1H-NMR, 13C-NMR and MS) and elemental analysis. The cytotoxicity of the compounds was evaluated using the Daphnia magna and Artemia salina bioassays.

THE ELECTROCHEMICAL MECHANISM OF SULFIDE SELF‐POTENTIALS

Geophysics ◽  
1960 ◽  
Vol 25 (1) ◽  
pp. 226-249 ◽  
Author(s):  
Motoaki Sato ◽  
Harold M. Mooney
Keyword(s):  
Water Table ◽  
Potential Drop ◽  
Reducing Agents ◽  
Oxidation Potential ◽  
Simultaneous Reduction ◽  
Oxidizing Agents ◽  
Ore Body ◽  
Oxidation Reduction ◽  
Ohmic Potential Drop ◽  
Different Depths

Self‐potentials associated with a sulfide ore body result from the ohmic potential drop within the country rocks. The electric current is produced by separate but simultaneous reduction of oxidizing agents near the surface and oxidation of reducing agents at depth. The ore does not participate directly in either reaction, but serves as a conductor to transfer the electrons from the reducing agents to the oxidizing agents. The possibility for the above reactions to occur depends upon differences in oxidation potential of ground waters at different depths. In the zone of weathering, the oxidation potential is controlled by the reduction mechanism of oxygen, and ranges in value from 0.2 to 0.7 volt (on the hydrogen scale). If the ore tends to oxidize at some lower potential, then the latter is the available one. In the zone beneath the water table, the potential is probably controlled by the oxidation‐reduction equilibria of iron‐rich minerals, and ranges in value from 0 to −0.3 volt. The available potential is independent of ore type. The maximum potential difference available to produce natural currents is estimated at: graphite 0.8, pyrite 0.7, covellite 0.6, chalcocite 0.5, galena 0.3 volt. Self‐potentials will be large if the ore body (1) is composed of minerals difficult to oxidize, (2) has low electrical resistance (physical continuity together with low resistivity), (3) extends vertically across the water table, and (4) exists close to the surface.

scholarly journals nfluence of reducing and oxidizing compounds and of the redox potential of the medium on the biomass of Scenedesmus quadricauda (Turp.) Breb.

2014 ◽  
Vol 53 (2) ◽  
pp. 223-235 ◽  
Author(s):  
Stefan Gumiński ◽  
Krystyna Jurajda ◽  
Ewa Tatkowska
Keyword(s):  
Ascorbic Acid ◽  
Redox Potential ◽  
Dry Weight ◽  
Reducing Agents ◽  
Scenedesmus Quadricauda ◽  
Oxidizing Agents ◽  
Weight Increment ◽  
Total Dry Weight

The influence was investigated of several concentrations of the reducing agents: cysteine, glutathione, ascorbic acid, pyracatechol and of the oxidizing agents: KMnO<sub>4</sub>, K<sub>4</sub>Cr<sub>2</sub>O<sub>7</sub> and H<sub>2</sub>O<sub>2</sub> on the total dry weight increment and that of protein with reference to redox potential changes of the medium in <em>Scenedesmus quadricauda</em> cultures. The culture was run in a photothermostat. It was found that the reducing compounds had as a rule a stimulating influence under 24-h illumdnation, whereas the oxidilzing agents gave the same effect when a period of 7-h darkness was applied within 24 h.

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