An insecticidal rocaglamide derivatives and related compounds from Aglaia adorata (Meliaceae)

Organic extracts of the twigs and leaves of Aglaia odorata yielded eight in secticidal cyclopentatetrahydrobenzofuran rocaglamide derivatives including three congeners which proved to be new natural products. Moreover, four ne w cyclopentatetrahydrobenzopyran aglain derivatives, as well as the known a minopyrrolidine odorine and odorinol, syringaresinol and flavonoid derivati ves were also isolated. Structure elucidation of the new compounds is descr ibed and a rationale of the biosynthesis of the rocaglamide and aglain cong eners is considered. The isolated rocaglamide derivatives exhibited strong insecticidal activity towards neonate larvae of the polyphagous pest insect Spodoptera littoralis when incorporated into artificial diet with LC50 val ues varying from 1.0-8.0 ppm. The most active compounds showed LC50 values between 1.0 and 1.1 ppm, comparable to those of the insecticide azadirachti n, which was used as a positive control. The remaining compounds isolated f rom A. odorata were inactive with regard to insecticidal activity. (C) 1999 Elsevier Science Ltd. All rights reserved.