Synthesis and anticoccidial activities of novel ethyl 6-aryloxy-7-bromo-4-hydroxy-3-quinolinecarboxylate against Eimeria tenella

A series of novel 7-bromo substituted derivatives of quinolinecarboxylate (4a-i) have been synthesized with short synthetic route and high yields. The structures were confirmed by 1H NMR, IR and MS. Anticoccidial activities of these compounds were evaluated according to the ACI (the anticoccidial index) method. The results indicated that four of the tested compounds (4a, 4b, 4e and 4g) exhibited anticoccidial activities obviously against Eimeria tenella at a dose of 27 mg kg−1 in the chicken' diet. In particular, the anticoccidial index of compound 4b (introduction 4-bromophenoxy at C-6 and bromine atom at C-7 of quinolinecarboxylate) was 170.0, which indicated that this compound has high anticoccidial activity.