Insect antifeedants, pterocarpans and pterocarpol, in heartwood of Pterocarpus macrocarpus Kruz.
The insect antifeedant activities of pterocarpans and a sesquiterpene alcohol from the dichloromethane extract of Pterocarpus macrocarpus Kruz. (Leguminosae) were evaluated against the common cutworm, Spodoptera litura F. (Noctuidae), and the subterranean termite, Reticulitermes speratus (Kolbe)(Rhinotermitidae). Three pterocarpans, (-)-homopterocarpin (1), (-)-pterocarpin (2), and (-)-hydroxyhomopterocarpin (3) and the sesquiterpene alcohol, (+)-pterocarpol (5), were isolated from the dichloromethane extract of the heartwood of P. macrocarpus under guidance by a biological assay. Among these natural products, the most active insect antifeedant against both S. litura and R. speratus was 1. On the other hand, sesquiterpene alcohol 5 showed less insect antifeedant activity than the other pterocarpans against both insect species. While its methylated derivative, (-)-methoxyhomopterocarpin (4), showed high biological activity, 3 showed less insect antifeedant activity in this study. Interestingly, racemic 1 did not show insect antifeedant activity against S. litura. However, all of the test pterocarpans and isoflavones showed antifeedant activity against the test termites. Additionally, since these compounds were major constituents of P. macrocarpus, these antifeedant phenolics may act as chemical defense factors in this tree. In Thailand, lumber made from this tree is used to make furniture and in building construction due to its resistance to termite attack.
Morimoto
Masanori
M
Department of Agricultural Chemistry, Faculty of Agriculture, Kinki University, Nakamachi, Japan. masanori@nara.kindai.ac.jp
Fukumoto
Hiromi
H
Hiratani
Masaru
M
Chavasiri
Warinthorn
W
Komai
Koichiro
K
D000438:Alcohols / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D000818:Animals; D001572:Benzofurans / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D001578:Benzopyrans / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D005247:Feeding Behavior / Q000187:drug effects; D020049:Isoptera / Q000187:drug effects; D008968:Molecular Conformation; D009036:Moths / Q000187:drug effects; D010572:Pest Control, Biological; D010936:Plant Extracts / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry*; D036343:Pterocarpans / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D035721:Pterocarpus / Q000737:chemistry*; D012717:Sesquiterpenes / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D013045:Species Specificity; D013237:Stereoisomerism; D014934:Wood
D000438:Alcohols; D001572:Benzofurans; D001578:Benzopyrans; D010936:Plant Extracts; D036343:Pterocarpans; D012717:Sesquiterpenes; C514760:homopterocarpin; C514761:pterocarpol