Synthesis and Antifungal Activity of Novel Quinazolin-4(3<i>H</i>)-one Derivatives

A novel group of 6-iodoquinazolin-4(<i>3H</i>)-one derivatives was prepared starting from 6-iodo-2-ethoxy-4<i>H</i>-3,1-benzoxazin-4-one <b>(3)</b> via action of various nitrogen nucleophiles such as primary and secondary amines, hydrazine hydrate, and its derivatives. The 3-amino-2-hydrazinyl-6-iodoquinazolin-4(<i>3H</i>)-one <b>(15)</b> was used as a key starting material to prepare new heterocyclic compounds. The structures of all synthesized compounds were inferred from the infrared, mass spectral, and ¹H NMR spectral data as well as elemental analysis. The fungicidal activities of the target compounds were preliminarily evaluated.