Bioactivity-directed investigation of root extract of Derris scandens has led to the isolation and characterization of a new benzil derivative (11), along with ten known compounds (1-10). Their structures were determined on the basis of extensive spectroscopic (IR, MS, 1D and 2D NMR) data analysis and by comparison with the literature data. The insect antifeedant activity and growth inhibitory studies of these compounds were investigated against castor semilooper pest, Achaea janata using a no-choice laboratory bioassay. Several of the isolates displayed potent feeding deterrence and were also toxic or caused developmental abnormalities following topical administration. The new compound, derrisdione A was moderately active with an antifeedant index of 58.6+/-1.7% at 10microg/cm(3) against A. janata.Copyright 2009 Elsevier Ltd. All rights reserved.
