Design, Synthesis, and Properties of Silicon-Containing -Diamide Insecticides.

Silicon-containing compounds are sporadically used in crop protection and drug discovery and have demonstrated to increase the biological efficacy as well as to reduce toxicity, improve physicochemical properties, and favorably impact the environmental profile. As part of our research, we have investigated the application of bioisosteric silicon replacements in -diamide insecticides and studied the biological activity and molecular properties of the corresponding novel compounds. At all meaningful structural elements of the -diamides, silicon-containing substituents were introduced and synthetic methodology was developed for their syntheses. As the most promising compound, silicon-containing -diamide emerged, which exhibits a very low LC value of 2.00 mg/L against and compares well to the reference compounds (LC = 0.17 mg/L) and (LC = 0.27 mg/L). Our research on silicon-containing crop protection compounds once again confirmed that the biological activity can be beneficially affected by the insertion of silicone substituents and that the introduction of well-chosen silicone motifs is an excellent strategy for agrochemical research.