Isolation and identification of a cis-C8-diol-ester of okadaic acid from Dinophysis acuta in New Zealand.

Abstract A cis -isomer of a C 8 -diol ester of okadaic acid ( 1 ) was isolated during large-scale purification of pectenotoxins (PTXs) from extracts of Dinophysis acuta collected from the west coast of South Island, New Zealand. The compound was identified by NMR spectroscopic and liquid chromatography-mass spectrometry (LC-MS) studies, and is the first reported cis -isomer of an okadaic acid C 8 -diol-ester identified in Dinophysis . The more abundant trans -C 8 -diol ester of okadaic acid ( 2 ) isolated from the same Dinophysis extract was rapidly hydrolyzed to okadaic acid in vitro by the supernatant from green-lipped mussel hepatopancreas.