Design, synthesis and acaricidal activity of novel butenolide containing trifluoroethyl sulfide (sulfoxide) compounds

In order to discover new acaricides with high activity, the lead compound sulfiflumin was modified, a series of novel butenolide containing trifluoroethyl sulfide (sulfoxide) compounds were designed and synthesized. First, butenolide containing trifluoroethyl sulfide (sulfoxide) C1 as a key compound was synthesized from the highly active fragment 4-methyl-2-fluoro-5-(2,2,2-trifluoroethyl thiothionyl) aniline and ethyl chloroacetoacetate. Then C2-C8 were synthesized by oxidation, chlorination or bromination of compound C1, or replacement with thiolact- one ring and dithioketone ester ring. The target compounds were characterized by ¹H NMR, ¹³C NMR and HRMS. Acaricidal activity showed that compounds C1-C8 had certain acaricidal activity, especially for the egg of Tetranychus cinnabarinus with 67%-93% activity. Moreover, the mortality rate of compound C3 against adults Tetranychus urticae was 100%. This work provides a guideline for the modification of butenolide containing trifluoroethyl sulfide (sulfoxide) compounds and flupyradifurone and is of reference significance for exploring biological activities.