Credneramides A and B: Neuromodulatory Phenethylamine and Isopentylamine Derivatives of a Vinyl Chloride-Containing Fatty Acid from cf. <i>Trichodesmium</i> sp. nov.

Credneramides A (<b>1</b>) and B (<b>2</b>), two vinyl chloride-containing metabolites, were isolated from a Papua New Guinea collection of cf. <i>Trichodesmium</i> sp. nov. and expand a recently described class of vinyl chloride-containing natural products. The precursor fatty acid, credneric acid (<b>3</b>), was isolated from both the aqueous and organic fractions of the parent fraction as well as from another geographically and phylogenetically distinct cyanobacterial collection (Panama). Credneramides A and B inhibited spontaneous calcium oscillations in murine cerebrocortical neurons at low micromolar concentrations (<b>1</b>, IC₅₀ 4.0 μM; <b>2</b>, IC₅₀ 3.8 μM)