Limonoid antifeedants from seed of Sandoricum koetjape.

An extract of the seed of Sandoricum koetjape has yielded two new limonoids, sandoricin [1] and 6-hydroxysandoricin [2]. Both compounds are effective antifeedants when incorporated into artificial diets and fed to fall armyworm (Spodoptera frugiperda) or European corn borer (Ostrina nubilalis) larvae. Reduced growth rates and increased times to pupation were evident at lower dose levels while significant mortality was noted at higher dose levels. Structures of both compounds were determined by 1H nmr, 13C nmr, and ms and confirmed by X-ray crystallography.