1) The acylation of N-(2-amino-5-nitrobenzoyl)-o-toluidine (I) with fluoroacetyl chloride by means of pyridine in THF gives N-(2-fluoroacetamido-5-nitrobenzoyl)-o-toluidine (II), which is cyclized by means of refluxing acetic anhydride acetic acid to yield 6-nitro-2-fluoromethyl-3-(o-tolyl)-4(3H)-quinazolinone (III). Finally, this compound is reduced with H2 over Pd/C in acetic acid or with SnCl2 - HCl in methanol - water. 2) The acylation of (I) with chloroacetyl chloride as before gives N-(2-chloroacetamido-5-nitro-benzoyl)-o-toluidine (IV), which is cyclized with acetic anhydride as before affording 6-nitro-2-chloromethyl-3-(o-tolyl)-4(3H)-quinazolinone (V). Finally, the treatment of (V) with KF in refluxing diethylene glycol yields (III).
3) The reduction of (V) with SnCl2 as before gives 6-amino-2-chloromethyl-3-(o-tolyl)-4(3H)-quinazolinone (VI), which is acylated with acetyl chloride as before to yield 6-acetamido-2-chloromethyl-3-(o-tolyl)-4(3H)-quinazolinone (VII). The treatment of (VII) with KF in diethylene glycol at 160 C yields 6-acetamido-2-fluoromethyl-3-(o-tolyl)-4(3H)-quinazolinone (VIII), which is finally deprotected by treatment with HCl in methanol.