5-Nitroanthranilonitrile (I) was converted into the corresponding formamidine (II) using dimethylformamide dimethyl acetal. Heating a solution of formamidine (II) and 3-bromoaniline (III) in HOAc gave the nitro quinazoline (IV). The nitro group of (IV) was then reduced with iron in HOAc to yield the intermediate amino quinazoline (V).
Methyl 4-bromocrotonate (VI) was hydrolyzed with barium hydroxide under controlled conditions and the resulting bromocrotonic acid (VII) was converted to the corresponding acid chloride (VIII) by treatment with oxalyl chloride. Condensation of acid chloride (VIII) with amino quinazoline (V) produced the bromocrotonamide (IX). Finally, nucleophilic displacement of the allylic bromine with dimethylamine provided the title compound.