Semisynthesis of new ethers from furyl-ring-based acylation derivatives of fraxinellone as insecticidal agents against Mythimna separata Walker in vivo

Abstract Fraxinellone, a naturally occurring degraded limonoid, is mainly isolated from Dictamnus dasycarpus and Melia azedarach . In continuation of our program aimed at the discovery of plant natural products-based insecticidal agents, twenty-two new ethers from furyl-ring-based acylation derivatives were prepared by structural modifications of fraxinellone. Their insecticidal activity was evaluated against the pre-third-instar larvae of Mythimna separata Walker in vivo . Among them, compounds 5e and 5j exhibited more potent insecticidal activity than toosendanin with the final mortality rates greater than 60%. Their structure-activity relationships were also discussed.