Insecticidal flavaglines and other compounds from Fijian Aglaia species

Bioassays with lipophilic crude extracts of four Fijian Aglaia species agai nst Spodoptera littoralis displayed strong insecticidal activity for A. bas iphylla and A. gracilis, whereas A. archboldiana and A. vitiensis did not h ave any significant effects. The insect toxicity of A. basiphylla was cause d by the well known benzofuran flavaglines rocaglamide, desmethylrocaglamid e and aglafoline. In contrast, A. gracilis contained four related pyrimidin one derivatives in the root and stem bark, including two new congeners name d marikarin and 3 ' -hydroxymarikarin. Moreover, two new putrescine bisamid es, secoodorine and secopiriferine, a new benzopyran flavagline, desacetyla glain A, and a new norsesquiterpene were isolated from the leaves together with three known bisamides and 3-hydroxy-5,7,4 ' -trimethoxyflavone. The st ructures of the new compounds were elucidated by spectroscopic methods. Com parative feeding assays within the active pyrimidinone flavaglines showed t hat the free hydroxy group in aromatic ring A of marikarin diminishes insec ticidal activity. (C) 2001 Elsevier Science Ltd. All rights reserved.