Abstract: Fourteen novel silicon-containing derivatives 3 of 1-methylthioethylideneamino methylcarbamate (Methomyl) were synthesized and their insecticidal and antiacetylcholinesterase activities were also determined. Results showed compounds 3 have a high insecticidal activity against armyworm (Mythimna separata Walker) at 50μg/mL . Most of them have an anti-acetylcholinesterase activity nearly equal to the parent Methomyl 1 when Periplaneta mericana was used as testing insect.

Key words: carbamate, silicon derivatization, insecticidal activity, antiacetyl- cholinesterase activity