Blonanserin (CAS NO.: 132810-10-7), with its systematic name of MCycloocta(b)pyridine, 2-(4-ethyl-1-piperazinyl)-4-(1-fluorophenyl)-5,6,7,8,9,10-hexahydro-, could be produced through many synthetic methods.

Following is one of the synthesis routes: Cyclooctanone (I) is condensed with 4-fluorobenzoylacetonitrile (II) by heating with polyphosphoric acid at 120 °C to afford 4-fluorophenyl-5,6,7,8,9,10-hexahydrocycloocta[b]pyridin-2(1H)-one (III), which is converted to the corresponding 2-chloro derivative (IV) by treatment with refluxing phosphoryl chloride. The reaction of (IV) with 1-ethylpiperazine (V) at 170 °C affords AD-5423.