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Stability of cyclic imine toxins: interconversion of pinnatoxin amino ketone and pinnatoxin A in aqueous media.

ABSTRACT: Pinnatoxins belong to the cyclic imine (CI) group of marine toxins with a unique toxicological profile. The need for structural integrity of the aliphatic 7-membered cyclic imine for the potent bioactivity of pinnatoxins has been experimentally demonstrated. In this study, we probe interconversion of the natural cyclic imine and its open form, pinnatoxin A amino ketone (PnTX AK), under physiologically relevant aqueous conditions. Our studies demonstrate the high stability of PnTX A. The unusual stability of the imine ring in PnTX A has implications for its oral toxicity and detoxification. These studies, as well the access to PnTX amino ketone, were enabled by the total synthesis of (+)-pinnatoxin A completed previously in our laboratory.

SUBMITTER: Jackson JJ

PROVIDER: S-EPMC4117372 | biostudies-literature | 2012 Nov

REPOSITORIES: biostudies-literature

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Stability of cyclic imine toxins: interconversion of pinnatoxin amino ketone and pinnatoxin A in aqueous media.

Jackson Jeffrey J JJ Stivala Craig E CE Iorga Bogdan I BI Molgó Jordi J Zakarian Armen A

The Journal of organic chemistry 20121106 22

Pinnatoxins belong to the cyclic imine (CI) group of marine toxins with a unique toxicological profile. The need for structural integrity of the aliphatic 7-membered cyclic imine for the potent bioactivity of pinnatoxins has been experimentally demonstrated. In this study, we probe interconversion of the natural cyclic imine and its open form, pinnatoxin A amino ketone (PnTX AK), under physiologically relevant aqueous conditions. Our studies demonstrate the high stability of PnTX A. The unusual ...[more]

PMID: 23116445

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