Habenariol, a freshwater feeding deterrent from the aquatic orchid Habenaria repens (Orchidaceae)

An uncommon ester, bis-p-hydroxybenzyl-2-isobutylmalate, habenariol, has be en isolated, by bioassay guided fractionation, from the organic extract of the freshwater orchid Habenaria repens. The structure of habenariol was det ermined by the interpretation of spectral data. Feeding bioassays showed th at habenariol deters feeding by the common freshwater crayfish Procambarus clarkii. Habenariol is related to a bis-ester glycoside isolated from the n on-aquatic orchid Galeola faberi. (C) 1999 Elsevier Science Ltd. All rights reserved.