Synthesis and anticoccidial activities of substituted ethyl 4-hydroxy-11-oxo-11H-chromeno[2,3-g]quinoline-3-carboxylates

A series of substituted ethyl 4-hydroxy-11-oxo-11H-chromeno[2,3-g]quinoline-3-carboxylates were designed and synthesised as anticoccidial drugs, and the structures were characterised by H-1 NMR, MS, IR spectra and elementary analysis. The anticocciadial activities of the new compounds were assessed according to the anticoccidial index method. The results demonstrated that four of these compounds exihibited effective anticoccidial activities against Eimeria tenella in chicken's diet with a dose of 27 mg kg(-1).