Seven novel 4-thioquinazoline compounds were synthesized by the reaction of 4-chloroquinazoline with mercapto compounds in acetone using anhydrous K₂CO₃. The structures of the title compounds were characterized by elemental analyses, IR, ¹H NMR and ¹³C NMR spectra. The results of bioassay showed that compound 1d had good antifungal activity against Fusarium graminearum, Fusarium oxysporum and Cytospora mandshurica with respective inhibition rate of 69.5%, 71.9% and 70.8% at the concentration of 50 μg•mL^－1, and EC₅₀ of 1d was 25.88, 17.08 and 28.77 μg•mL^－1.

Key words: antifungal activity, quinazoline, synthesis