Abstract Ethyl 2, 4-dioxo-4-(p-chloro) phenylbutyrate 2 obtained by condensation of 4- chloroacetophenone with diethyl oxalate was converted to 5-(4-chlorophenyl)-1-phenyl-1 H- pyrazole-3-carbohydrazide 5 and 5-(4-chlorophenyl) isoxazole-3-carbohydrazide 6 in good yields. Treatment of 5 or 6 with phenylisothiocyanate and reaction of the resulting thiosemicarbazide 7 or 8 with chloroacetic acid and 4-fluorobenzaldehyde, phenacyl ...