Structure elucidation, relative LC-MS response and in vitro toxicity of Azaspiracids 7-10 isolated from blue mussels (Mytilus edulis)

Azaspiracids (AZAs) 7-10 (7-10) were isolated from shellfish and their structures, previously proposed based only on LC-MS/MS data, were confirmed by NMR spectroscopy. Samples of AZA4-6 (4-6) and 7-10 were accurately quantitated by qNMR, and used to prepare reference standards and assay cytotoxicity with Jurkat T lymphocyte cells. LC-MS molar response studies performed using isocratic and gradient elution, in both SIM and SRM modes, showed that responses for the analogues ranged from 0.3 to 1.2 relative to AZA1 (1). All AZA analogues tested were cytotoxic to Jurkat T lymphocyte cells in a time- and concentration\uad dependent manner. However, there were distinct differences in their EC50 values, with cytotoxicity potencies being 6 > 8 > 1 > 4 48 5 489 > 10. This provides valuable information on structure-activity relationships.Peer reviewed: YesNRC publication: Ye