Synthesis of Novel Indole Schiff Base Compounds and Their Antifungal Activities.

A series of novel indole Schiff base derivatives (-) containing a 1,3,4-thiadiazole scaffold modified with a thioether group were synthesized, and their structures were confirmed using FT-IR, H NMR, C NMR, and HR-MS. In addition, the antifungal activity of synthesized indole derivatives was investigated against (), (, (), ), and var. ( var. ) using the mycelium growth rate method. Among the synthesized indole derivatives, compound showed the highest inhibition rates of 100%, 95.7%, 89%, and 76.5% at a concentration of 500 μg/mL against , , , and var. , respectively. Similarly, compounds and exhibited higher inhibition rates of 81.9% and 83.7% at a concentration of 500 μg/mL against . In addition, compound has been recognized as a potential compound for further investigation in the field of fungicides.