Benzoxazinone Pyridylpyrazole Fungicides

Metal-free green synthesis

These derivatives, synthesized via a metal-free route, exhibit high inhibitory activity against maize rust and cucumber anthracnose, offering a new scaffold for eco-friendly fungicide development.

Liu, Jing · Du, Xiaohua

International Journal of Molecular Sciences 2026

Specifications

Inhibition rate against maize rust

{'zh': '92.0', 'en': '92.0'} %

Inhibition rate against cucumber anthracnose

{'zh': '90.5', 'en': '90.5'} %

Maximum yield

{'zh': '63.7', 'en': '63.7'} %

Binding energy with SDHI

{'zh': '-11.8', 'en': '-11.8'} kcal/mol

Advantages

Metal-catalyst-free

The synthetic route avoids metal catalysts, uses mild conditions, and yields products free of metal residues, aligning with green pesticide requirements.

High efficacy against maize rust

Compound 8p achieved 92.0% inhibition against maize rust at 50 mg/L, approaching commercial fungicide levels.

High efficacy against cucumber anthracnose

Compound 8q exhibited 90.5% inhibition against cucumber anthracnose at 50 mg/L, indicating broad-spectrum potential.

Strong target binding

Docking revealed compound 8j binds to SDHI with a binding energy of -11.8 kcal/mol, and the polar interaction between its carbonyl group and Lys163 enhances affinity.

Applications

• Maize rust control：Maize rust control requires effective low-toxicity agents; 8p at 50 mg/L shows 92.0% inhibition, suitable for rotation or replacement.
• Cucumber anthracnose control：Cucumber anthracnose is a key vegetable disease; 8q at 50 mg/L shows 90.5% inhibition, offering a new control option.
• Succinate dehydrogenase inhibitors：The derivatives act as SDH inhibitors, providing new scaffolds for SDHI-based pesticides.