ChemInform Abstract: Structure and Reactivity of Xanthocorrinoids. Part 5. Formation of trans-Diol Derivatives of 5,6-Dihydrocobyrinic Acid from Xanthocorrinoids Under Acidic Conditions.

ChemInform ◽  
2010 ◽  
Vol 22 (47) ◽  
pp. no-no
Author(s):  
G. HOLZE ◽  
T. A. JENNY ◽  
P. NESVADBA ◽  
A. GOSSAUER ◽  
L. ERNST ◽  
...  
Keyword(s):  
Acidic Conditions ◽  
Abstract Structure ◽  
Derivatives Of

ChemInform Abstract: STRUCTURE OF SOME N-GLYCOSIDE DERIVATIVES OF 5-AMINO-SUBSTITUTED 6-AZAURACILS

1979 ◽  
Vol 10 (26) ◽  
Author(s):  
I. V. ALEKSEEVA ◽  
A. S. SHALAMAI ◽  
E. G. SIDORENKO ◽  
V. P. CHERNETSKII
Keyword(s):  
Abstract Structure ◽  
Derivatives Of

scholarly journals Phenacylation of 6-Methyl-Beta-Nitropyridin-2-Ones and Further Heterocyclization of Products

Molecules ◽  
2020 ◽  
Vol 25 (7) ◽  
pp. 1682
Author(s):  
Eugene V. Babaev ◽  
Victor B. Rybakov
Keyword(s):  
Pyridinium Salt ◽  
Phenacyl Bromides ◽  
Acidic Conditions ◽  
Phenacyl Derivatives ◽  
Derivatives Of

Reaction between the derivatives of 6-methyl-beta-nitropyridin-2-one and phenacyl bromides was studied, and the yields observed were extremely low. The pyridones were converted via chloropyridines to methoxyderivatives, which were N-phenacylated. N-Phenacyl derivatives of 4,6-dimethyl-5-nitropyridin-2-one under the action of base gave 5-hydroxy-8-nitroindolizine and under acidic conditions gave 5-methyl-6-nitrooxazole[3,2-a]pyridinium salt, which underwent recycization with MeONa to 5-methoxy-8-nitroindolizine.

scholarly journals Cyclotrimerization of 3-R-1,2,4-Triazin-5(4H)-ones with Cyclic Ketones

2010 ◽  
Vol 65 (11) ◽  
pp. 1359-1362 ◽  
Author(s):  
Ilya N. Egorov ◽  
Igor S. Kovalev ◽  
Vladimir L. Rusinov ◽  
Oleg N. Chupakhin
Keyword(s):  
Cyclic Ketones ◽  
Acidic Conditions ◽  
Derivatives Of

New heterocyclic tetracyclic systems were synthesized. Interaction between 3-R-1,2,4-triazin- 5(4H)-ones and cyclic ketones under acidic conditions leads to the formation of zwitterion derivatives of 5,6,7,8,9,10,11,12-octahydro-[1,2,4]triazino[1,6- ƒ ]phenanthridine and 1,2,3,6,7,8-hexahydro-bicyclopenta[ b,d]pyrido[1,2- ƒ ][1,2,4]triazine.

Oxyhalogen–sulfur chemistry — Kinetics and mechanism of the bromate oxidation of cysteamine

2008 ◽  
Vol 86 (5) ◽  
pp. 416-425 ◽  
Author(s):  
Moshood K Morakinyo ◽  
Edward Chikwana ◽  
Reuben H Simoyi
Keyword(s):  
Oxidation Product ◽  
Reducing Agent ◽  
Kinetics And Mechanism ◽  
Molecular Bromine ◽  
Sulfur Chemistry ◽  
Diffusion Controlled ◽  
Hypobromous Acid ◽  
Acidic Conditions ◽  
Acid Toxicity ◽  
Derivatives Of

The kinetics and mechanism of the oxidation of the biologically important molecule, cysteamine, by acidic bromate and molecular bromine have been studied. In excess acidic bromate conditions, cysteamine is oxidized to N-brominated derivatives, and in excess cysteamine the oxidation product is taurine according to the following stoichiometry: BrO3– + H2NCH2CH2SH → H2NCH2CH2SO3H + Br–. There is quantitative formation of taurine before N-bromination commences. Excess aqueous bromine oxidizes cysteamine to give dibromotaurine: 5Br2 + H2NCH2CH2SH + 3H2O → Br2NCH2CH2SO3H + 8Br– + 8H+, while excess cysteamine conditions gave monobromotaurine. The oxidation of cysteamine by aqueous bromine is effectively diffusion-controlled all the way to the formation of monobromotaurine. Further formation of dibromotaurine is dependent on acid concentrations, with highly acidic conditions inhibiting further reaction towards formation of dibromotaurine. The formation of the N-brominated derivatives of taurine is reversible, with taurine regenerated in the presence of a reducing agent such as iodide. This feature makes it possible for taurine to moderate hypobromous acid toxicity in the physiological environment.Key words: cysteamine, hypobromous acid, toxicities, antioxidant.

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