Fungal pathogens pose a significant threat to global food security, with fungicides remaining the most direct and effective control strategy currently available. To combat the increasing pathogen resistance, 24 novel target compounds were designed and synthesized by integrating the naturally occurring quinazolinone scaffold with the bioactive hydrazide pharmacophore. All synthesized structures were characterized using 1H nuclear magnetic resonance (NMR), 13C NMR, and high-resolution mass spectrometry (HRMS). Fungicidal bioassays revealed that some compounds exhibited outstanding and broad-spectrum antifungal activity, among which compound W13 displayed exceptional efficacy with median effective concentration (EC50) values of 0.80, 4.84, 2.70, 2.94, 1.87, 3.14, and 4.35 μg/mL against Rhizoctonia solani, Magnaporthe oryzae, Sclerotinia sclerotiorum, Colletotrichum gloeosporioides, Physalospora piricola, Botrytis cinerea, Alternaria sp., respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observations indicated that compound W13 likely disrupted the normal physiological activities of R. solani by interfering with the functions of biofilm and mitochondria. Lipidomics analysis further demonstrated that treatment with compound W13 significantly reduced the total lipid content in R. solani, with notable alterations observed in lipids of different carbon chain lengths and degrees of unsaturation. Additionally, W13 treatment caused a marked decrease in ergosterol levels, supporting its effect on disrupting the biofilm function. Zebrafish toxicity assessments showed a 100 % survival rate after 7 days at 1 μg/mL, while the 10 μg/mL treatment group exhibited a survival rate of only 10 % by the sixth day. These findings will provide important insights for the development of novel environmentally friendly hydrazide-based fungicides.