Category: 99429-68-2

Croitoru, M. D. published the artcileDirect HPLC-UV determination of cyclemate, saccharine and aspartame from soft drinks, Recommanded Product: Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate, the main research area is cyclamate saccharine aspartame soft drink HPLC UV detection.

Artificial sweeteners were introduced in therapy as sugar substitutes for diabetic patients. Nowadays these substances are widely used for sugar substitution in low calorie drinks and sweets. Most commonly used products to date are saccharine, cyclamate, aspartame, and acesulfam; maximum accepted daily intakes are stated for each one. A simple reverse phase (RP18) HPLC-UV method with direct detection (196 nm) was developed by us in order to measure the concentrations of the three sweeteners. No sample preparation is required, other than dilution Limits of detection are 12 mg l-1, 0.5 mg l-1 and lower than 0.25 mg l-1 for cyclamate, aspartame and saccharine, resp. Concentrations ranged between 113.14-280.07 mg l-1 in the case of cyclamate, 17.96-50.94 mg l-1 for saccharine, and 9.94-296.82 mg l-1 for aspartame.

Acta Alimentaria published new progress about Beverages. 99429-68-2 belongs to class pyridine-derivatives, name is Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate, and the molecular formula is C10H9NO4S, Recommanded Product: Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Barker, John M. published the artcileThienopyridines. Part 7. Some electrophilic substitution reactions of thieno[2,3-b]- and -[3,2-b]pyridine isosteres of 4-oxygenated and 2,4-dioxygenated quinolines, Product Details of C10H9NO4S, the main research area is electrophilic substitution thienopyridine regiochem; quinolinone isostere electrophilic substitution.

Electrophilic substitution reactions were examined of the title compounds I, II [X = NMe, X1 = CO (III); X = CO, X1 = NH (IV), NMe (V)], VI, and VII. The 4-quinolone analogs I and IV, like the parent compound, were monobrominated and (diethylamino)methylated in the pyridine ring α to the CO group. However, whereas 4-quinolone and IV were nitrated in the pyridine ring by HNO3 alone, I was nitrated mainly in the thiophene ring at C-2 under these conditions. The methylated compounds III and V showed a similar regiochem. to their nonmethylated analogs, although their reactivity was lower. I and II were dinitrated by mixed HNO3-H2SO4 at the position α to the CO group in the pyridine ring and at either C-2 in the [2,3-b] isomers (I and III) or C-3 in the [3,2-b] compounds (IV and V); dibromination of I, III, and IV followed a similar pattern. Mannich reactions of VI and VII occurred in the pyridine rings, whereas bromination occurred in the thiophene and pyridine rings in VI and VII, resp.

Journal of Chemical Research, Synopses published new progress about Bromination. 99429-68-2 belongs to class pyridine-derivatives, name is Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate, and the molecular formula is C10H9NO4S, Product Details of C10H9NO4S.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Croitoru, M. D. published the artcileDirect HPLC-UV determination of cyclemate, saccharine and aspartame from soft drinks, Recommanded Product: Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate, the main research area is cyclamate saccharine aspartame soft drink HPLC UV detection.

Artificial sweeteners were introduced in therapy as sugar substitutes for diabetic patients. Nowadays these substances are widely used for sugar substitution in low calorie drinks and sweets. Most commonly used products to date are saccharine, cyclamate, aspartame, and acesulfam; maximum accepted daily intakes are stated for each one. A simple reverse phase (RP18) HPLC-UV method with direct detection (196 nm) was developed by us in order to measure the concentrations of the three sweeteners. No sample preparation is required, other than dilution Limits of detection are 12 mg l-1, 0.5 mg l-1 and lower than 0.25 mg l-1 for cyclamate, aspartame and saccharine, resp. Concentrations ranged between 113.14-280.07 mg l-1 in the case of cyclamate, 17.96-50.94 mg l-1 for saccharine, and 9.94-296.82 mg l-1 for aspartame.

Acta Alimentaria published new progress about Beverages. 99429-68-2 belongs to class pyridine-derivatives, name is Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate, and the molecular formula is C10H9NO4S, Recommanded Product: Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Barker, John M. published the artcileThienopyridines. Part 7. Some electrophilic substitution reactions of thieno[2,3-b]- and -[3,2-b]pyridine isosteres of 4-oxygenated and 2,4-dioxygenated quinolines, Product Details of C10H9NO4S, the main research area is electrophilic substitution thienopyridine regiochem; quinolinone isostere electrophilic substitution.

Electrophilic substitution reactions were examined of the title compounds I, II [X = NMe, X1 = CO (III); X = CO, X1 = NH (IV), NMe (V)], VI, and VII. The 4-quinolone analogs I and IV, like the parent compound, were monobrominated and (diethylamino)methylated in the pyridine ring α to the CO group. However, whereas 4-quinolone and IV were nitrated in the pyridine ring by HNO3 alone, I was nitrated mainly in the thiophene ring at C-2 under these conditions. The methylated compounds III and V showed a similar regiochem. to their nonmethylated analogs, although their reactivity was lower. I and II were dinitrated by mixed HNO3-H2SO4 at the position α to the CO group in the pyridine ring and at either C-2 in the [2,3-b] isomers (I and III) or C-3 in the [3,2-b] compounds (IV and V); dibromination of I, III, and IV followed a similar pattern. Mannich reactions of VI and VII occurred in the pyridine rings, whereas bromination occurred in the thiophene and pyridine rings in VI and VII, resp.

Journal of Chemical Research, Synopses published new progress about Bromination. 99429-68-2 belongs to class pyridine-derivatives, name is Ethyl 4-hydroxy-6-oxo-6,7-dihydrothieno[2,3-b]pyridine-5-carboxylate, and the molecular formula is C10H9NO4S, Product Details of C10H9NO4S.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem