A mixture of 2.9 g (0.018 moles) of 1-phenyl-1,3-butanedione, 5.0 g (0.018 moles) of 3-amino-5-(4-phenylmethyl-1-piperazinyl)-4-pyrazolecarbonitrile (prepared as described in Example 1) and 25 ml of glacial acetic acid was refluxed for 4 hours. The reaction mixture was evaporated in vacuo and gave a thick oil. The oil was dissolved in dichloromethane and partitioned with saturated sodium bicarbonate. The organic layer was separated, dried over anhydrous sodium sulfate and passed through magnesium silicate. The solution was evaporated in vacuo and gave a yellow solid which was recrystallized from isopropanol and cyclohexane and gave 5.5 g of the desired product as a light yellow solid, mp 160°-164° C.
