1,10-Phenanthroline-3,8-dicarboxylic acid, 4,7-dihydroxy-, diethyl ester 3,8-Dicarboethoxy-4,7-dihydroxy-1,10-phenanthroline 39479-71-5 Diethyl 4,7-dihydroxy-1,10-phenanthroline-3,8-dicarboxylate EINECS 254-468-8