Synthesis and Reactions of Some New Quinazoline Derivatives for In Vitro Evaluation as Anticancer and Antimicrobial Agents

A novel series of N , O , S heterocyclic compounds incorporated at position‐3 of a quinazolin‐4(3 H )‐one moiety were synthesized through a p ‐phenloxy binding including oxadiazolethione pyridazinetrione, thiazolidinedione, benzothiazindione, and quinazolinedione. New carbamates, urea derivatives, and Mannich bases were also prepared for the purpose of in vitro anticancer cell lines evaluation and cytotoxic activity. The key intermediate 2‐(4‐chlorophenyl)‐3‐(4‐hydroxyphenyl)quinazolin‐4(3 H )‐one was prepared from the reaction of 4 H ‐benzo [d][3,1]oxazin‐4‐one and a nitrogenous nucleophilic compound, 4‐aminophenol. Some of the newly synthesized compounds showed significant cytotoxic activity.