Design, synthesis and anti-oomycete activity of 2-acyloxyhinokitiol derivatives.

In order to explore novel natural product-based anti-oomycete agent, ten 2-acyloxyhinokitiol derivatives () were designed and synthesised, and structurally confirmed by H NMR,C NMR, HRMS, and melting point. The stereochemical configuration of compound was unambiguously confirmed by single-crystal X-ray diffraction. Furthermore, we evaluated the target compounds as anti-oomycete activity against a serious agricultural disease of . Among the ten hinokitiol ester derivatives tested, four compounds , , and had anti-oomycete activity higher than the positive control zoxamide (EC = 23.59 mg/L), and the EC values of 18.90, 20.62, 13.61 and 21.29 mg/L, respectively. Especially compound exhibited the best anti-oomycete activity against with EC value of 13.61 mg/L. Overall, the anti-oomycete activities of 2-acyloxyhinokitiol derivatives is higher than that of 2-sulfonyloxyhinokitiol derivatives. The results laid a good foundation for the subsequent synthesis of hinokitiol ester derivatives with significant anti-oomycete activity.