Abstract
Marine algae from the genus Karlodinium are known to be involved in fish-killing events worldwide. Here we report for the first time the chemistry and bioactivity of a natural product from the newly described mixotrophic
dinoflagellate Karlodinium armiger. Our work describes the isolation and structural characterization of a new polyhydroxypolyene named karmitoxin. The structure elucidation work was facilitated by use of 13C enrichment and high-field 2D NMR spectroscopy, where 1H−13C long-range correlations turned out to be very informative. Karmitoxin is structurally related to amphidinols and karlotoxins; however it differs by containing the longest carbon−carbon backbone discovered for this class of compounds, as well as a primary amino group.
Karmitoxin showed potent nanomolar cytotoxic activity in an RTgill-W1 cell assay as well as rapid immobilization and eventual
mortality of the copepod Acartia tonsa, a natural grazer of K. armiger.
dinoflagellate Karlodinium armiger. Our work describes the isolation and structural characterization of a new polyhydroxypolyene named karmitoxin. The structure elucidation work was facilitated by use of 13C enrichment and high-field 2D NMR spectroscopy, where 1H−13C long-range correlations turned out to be very informative. Karmitoxin is structurally related to amphidinols and karlotoxins; however it differs by containing the longest carbon−carbon backbone discovered for this class of compounds, as well as a primary amino group.
Karmitoxin showed potent nanomolar cytotoxic activity in an RTgill-W1 cell assay as well as rapid immobilization and eventual
mortality of the copepod Acartia tonsa, a natural grazer of K. armiger.
| Original language | English |
|---|---|
| Journal | Journal of Natural Products |
| Volume | 80 |
| Issue number | 5 |
| Pages (from-to) | 1287−1293 |
| Number of pages | 7 |
| ISSN | 0163-3864 |
| DOIs | |
| Publication status | Published - 26 May 2017 |
