Design, Synthesis and Structure-Activity Relationship of Novel Pinacolone Sulfonamide Derivatives against Botrytis cinerea as Potent Antifungal Agents

To develop new fungicides with high efficiency, 46 novel sulfonamide derivatives were designed and synthesized by introducing pinacolone fragment into chesulfamide which was used as lead compound. All compounds were characterized by (1)H NMR, (13)C NMR, and MS spectra, and the structure of compound P-27 was also confirmed by X-ray single crystal diffraction. It was found that a variety of compounds present excellent inhibitory effect against Botrytis cinerea. The inhibition rates of P-29 on tomato and strawberry were 90.24% (200 mg/L) and 100% (400 mg/L) in vivo respectively, which were better than the lead compound chesulfamide (59.23% on tomato seedlings and 29.63% on strawberries).