2-(2-Arylvinyl)-7-substituted-quinazolin-4(3H)-ones:: Synthesis, reactions and antimicrobial activity

7-Chloro-3-(4-hydroxyphenyl)-2-methylquinazolin-4(3H)-one 3a on condensation with ethyl chloroformate, epichlorhydrin and isocyanates gives 7-chloro-3-[4-ethoxycarbonyloxy)phenyl]-2-methylquinazolin-4(3H)-one 4a, 7-chloro-3-[4-(2,3-epoxypropoxy)phenyl]-2-methylquinazolin-4(3H)-ones 5a and 7-chloro-3-[4-(substituted amino carbonyloxy) phenyl]-2-methylquinazolin-4-(3H-ones) 6a,b, respectively which on condensation with the appropriate aldehyde yield 2-(2-arylvinyl)-7-chloro (or nitro)-3-[4-ethoxycarbonyloxy)phenyl]quinazolin-4(3H)-ones 4b,c, 2-(2-arylvinyl)-7-chloro-3-[4-(2,3-epoxypropoxy)phenyl]quinazolin-4 (3H)-ones 5b,c and 7-chloro-2-[2-(4-chlorophenyl)vinyl]-3-[4-substituted aminocarbonyloxy)phenyl]quinazolin-4(3H)-ones 6c,d, respectively. Also the compounds 4b-d and 5b-d have been synthesized by reacting 2-(2-arylvinyl)-7-chloro (or nitro)-3-(4-hydroxyphenyl) quinazolin-4(3H)-ones 3b-d with ethyl chloroformate and epichlorohydrin, respectively. 7-Chloro-2-[2-(4-chlorophenyl)vinyl]-3-[4-(substituted aminocarbonyloxy)-phenyl]quinazolin-4(3H)-ones 6c,e have also been,obtained from 3b by refluxing with isocyanates. Further, 4,7-dichloroquinazolines 10,b are obtained from 2-styrylquinazolinones 9a,b on treatment with POCl3. Compounds 10a,b on condensation with glycine in the presence of pyridine yield 2-(2-arylvinyl)-7-chloro-4-carboxymethylaminoquinazolines 11a,b which on fusion with Ac2O/NaOAc afford 5-(2-arylvinyl)-8-chloro-imidazo[1,2-c]quinazolin-3-3(2H)-ones 12a,b. Several compounds have been tested for their antimicrobial activity.