Letrozole (CAS NO.: 112809-51-5), with its systematic name of Benzonitrile, 4,4'-(1H-1,2,4-triazol-1-ylmethylene)bis-, could be produced through many synthetic methods.

Following is one of the synthesis routes:  4-Bromomethylbenzonitrile (I) reacts with 1,2,4-triazole (II) in chloroform - acetonitrile to afford 1-(4-cyanophenyl)methyl-1,2,4-triazole (III), which is treated with potassium tert-butoxide and 4-fluorobenzonitrile (IV) in DMF.