Synthesis and Biological Activity of New Fluorinated Thieno[2,3-d]pyrimidinyl Hydrazone Derivatives

A series of new fluorinated thieno[2,3-d]pyrimidine derivatives containing hydrazone substructure was synthesized by a five-step procedure, including trifluoroacetylation, cyclization, chlorination, substitution by hydrazine, and condensation reaction. The structures of these newly synthesized compounds were confirmed by IR, NMR, EI-MS, elemental analysis and single-crystal X-ray diffraction. The preliminary bioassay result showed that some title compounds exhibited relatively good fungicidal activity against Fusarium oxysporium f.sp.vasinfectum at the concentration of 50 μg·mL-1, especially the inhibition rate of compound 6b reached above 90%.