e under reflux for 00 hours. The synthetic procedure is illustrated in scheme II, below:  According to the '000 patent, 0-(0-chloropyrimidin-0-ylamino)benzonitrile of formula III-a can be prepared by reacting the 0-[(0,0-dihydro-0-oxo-0-pyrimidinyl)amino]benzonitrile with phosphorus oxytrichloride in the presence of methylene chloride and 0-propanone. 