111853-35-1Relevant articles and documents
Synthesis of 6′-carbamoylmethylthio-5′-cyano-1′,4′- dihydro-3,4′-bipyridine-3′-carboxylic and 6′- carbamoylmethylthio-5′-cyano-1′,4′-dihydro-4, (...)
Krauze,Vilums,Cernova,Sile,Duburs
, p. 708 - 714 (2008/03/11)
The stability of solutions of esters of 6′-carbamoylmethylthio- 5′-cyano-2′-methyl-1′,4′-dihydro-4,4′-bipyridine- 3′-carboxylic acids was investigated by HPLC. The corresponding esters of 6′-carbamoylmethylthio-5′-cyano-4,4′-bipyridine-3′- carboxylic acids,esters of 8-cyano-5-methyl-3-oxo-7-(4-pyridyl)-2,3-dihydro-7H- thiazolo-[3,2-a]pyridine-6-carboxylic acids, methyl 3-amino-2-carbamoyl-6- methyl-4-(4-pyridyl)-4,7-dihydrothieno[2,3-b]pyridine-5-carboxylate, and methyl 3-amino-2-carbamoyl-6-methyl-4-(4-pyridyl)-thieno[2,3-b]pyridine-5-carboxylate were synthesized as standard compounds (typical impurities). Analysis by HPLC was realized under the conditions of reverse-phase chromatography. It was established that solutions of the investigated compounds (with mixtures of acetonitrile with phosphate buffer, having pH values of not less than 3 and not more than 5, as solvents) are stable for one month when the solutions are stored in a place protected against light. It is also necessary to use chromatographic systems in which the aqueous components have pH 3-5 during determination of the purity of the esters of 6′-carbamoylmethylthio-5′-cyano-2′- methyl-1′,4′-dihydro-4, 4′-bipyridine-3′-carboxylic acid by HPLC in order to separate the analyzed sorbates and their typical impurities more completely.
