Twenty novel compounds of α-phenylsulfonylcyclododecanone oxime esters (8) were synthesized by the acylation of α-phenylsulfonylcyclododecanone oxime. Their structures were confirmed by elemental analysis, 1H NMR, and IR spectral data. The preliminary bioassay results showed that α-phenyl-sul-fonylcyclododecanone oxime 2,4-dichlorophenoxy acetate (8p) had inhibition ratio 100% and 80.07% against Digitaria sanguinalis (Linn.) Scop., and 100% and 88.70% against Abutilon theophrasti Medic. at concentrations of 100 and 1 mg/L. The IC50 for D. sanguinalis and IC50 for A. theophrasti of 8p were 0.192 and 0.151 mg/L, respectively.

Key words: α-phenylsulfonylcyclododecanone oxime ester, synthesis, herbicidal activi, α-phenylsulfonylcyclododecanone