The condensation of 1H-indole (I) with 4-chlorobenzyl chloride (II) by means of NaH in DMSO gives 1-(4-chlorobenzyl) indole (III), which is treated with oxalyl chloride in a hot aprotic solvent yielding the intermediate acid chloride (IV). Finally, this compound is treated with pyridin-4-amine (V) in the same solvent.