2.01 ml (13.92 mmol) of triethylamine and then 0.92 g (5.2 mmol) of cyclohexylmethyl bromide in 5 ml of acetonitrile are successively added at room temperature, under an argon atmosphere and with magnetic stirring, to a solution of 1.13 g (3.48 mmol) of 5-(4-amino-5-chloro-2-methoxyphenyl)-3-(piperidin-4-yl)-1,3,4-oxadiazol-2(3H)-one in 40 ml of acetonitrile and the mixture is stirred at 70° C. for 2 days. The solvent is evaporated under reduced pressure, the residue is taken up in chloroform, the solution is washed a number of times with water and dried, the solvent is evaporated under reduced pressure and the residue is crystallized from acetone. 0.7 g of white solid is obtained. Melting point: 186.5-186.7° C.
