Synthesis and insecticidal activity of 4"-deoxy-abamectin urea and thioure analogues

Based on SAR investigation, two series of abamectin analogues containing urea and acyl thiourea groups were designed according to analog synthesis and sub-structure. Their structures were confirmed by 1H NMR, MS and elemental analysis. Their insecticidal activity was tested against Tetranychus cinnabarinus and Brevicoryne brassicae. All the tested compounds showed significant inhibitory activity against the above two insect species. Notably, the majority of those compounds exhibited high selectivity against B. brassicae, some of which were much better in comparison to abamectin. Especially, compound 9h displayed more potent activity than abamectin against the above two insect species, namely, T. cinnabarinus (LC50=0.100 μmol/L) and B. brassicae (LC50=1.71 μmol/L).Moreover, compound 9o showed superior activity against B. brassicae, with LC50 value of 1.13 μmol/L.