Synonyms: ethyl 4-hydroxypyrimido[4,5-b]quinoline-2-carboxylate;Ethyl 4-oxo-3,4-dihydropyrimido[4,5-b]quinoline-2-carboxylate;pyrimido[4,5-b]quinoline-2-carboxylic acid, 3,4-dihydro-4-oxo-, ethyl ester;pyrimido[4,5-b]quinoline-2-carboxylic acid, 4-hydroxy-, ethyl ester