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Updated: Jun 16, 2026

Synthesis and Structure Determination of µ-Conotoxin PIIIA Isomers with Different Disulfide Connectivities
Published on: October 2, 2018
Structure and absolute configuration of karlotoxin-2, an ichthyotoxin from the marine dinoflagellate Karlodinium
Jiangnan Peng1, Allen R Place, Wesley Yoshida
1Department of Pharmacognosy and National Center for Natural Products Research, University of Mississippi, University, Mississippi 38677, USA.
Abstract:
In an attempt to determine the cause of repeated fish kills in an estuarine aquaculture facility in Maryland, a toxin with hemolytic, cytotoxic, and ichthyotoxic properties, designated as karlotoxin-2 (KmTx2), was isolated from Karlodinium veneficum. The structure of KmTx2 was elucidated by means of detailed ID and 2D NMR spectra, including 2D INADEQUATE. The relative and absolute configurations of KmTx2 were determined using J-based configuration analysis and comparison of its degradation products with synthetic controls.
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