Bromotryptamine and Bromotyramine Derivatives from the Tropical Southwestern Pacific Sponge Narrabeena nigra

Maria Miguel-Gordo (1) , Sandra Gegunde (2) , Kevin Calabro (1) , Laurence Jennings (3) , Amparo Alfonso (4) , Grégory Genta-Jouve (5, 6) , Jean Vacelet (7) , Luis Botana (2) , Olivier Thomas (1)

1 Natl Univ Ireland Galway, Sch Chem, Marine Biodiscovery, Galway, Ireland
2 USC - Universidade de Santiago de Compostela [Spain]
3 ICS - Institut Charles Sadron
4 Departamento de Farmacologia Facultad de Veterianaria
5 MCAM - Molécules de Communication et Adaptation des Micro-organismes
6 CiTCoM - UMR 8038 - Cibles Thérapeutiques et conception de médicaments
7 IMBE - Institut méditerranéen de biodiversité et d'écologie marine et continentale

So far, the Futuna Islands located in the Central Indo-Pacific Ocean have not been inventoried for their diversity in marine sponges and associated chemical diversity. As part of the Tara Pacific expedition, the first chemical investigation of the sponge Narrabeena nigra collected around the Futuna Islands yielded 18 brominated alkaloids: seven new bromotryptamine derivatives 1-7 and one new bromotyramine derivative 8 together with 10 known metabolites of both families 9-18. Their structures were deduced from extensive analyses of nuclear magnetic resonance (NMR) and high-resolution mass spectrometry (HRMS) data. In silico metabolite anticipation using the online tool MetWork revealed the presence of a key and minor biosynthetic intermediates. These 18 compounds showed almost no cytotoxic effect up to 10 µM on human neuroblastoma SH-SY5Y and microglia BV2 cells, and some of them exhibited an interesting neuroprotective activity by reducing oxidative damage.

Keywords: Narrabeena; Porifera; Futuna; Bromotryptamine; Bromotyramine; neuroprotective agents; aromatic alkaloids; coral reefs

Domains: Chemical Sciences; Environmental Sciences; Biodiversity and Ecology

Maria Miguel-Gordo, Sandra Gegunde, Kevin Calabro, Laurence Jennings, Amparo Alfonso, et al.. Bromotryptamine and Bromotyramine Derivatives from the Tropical Southwestern Pacific Sponge Narrabeena nigra. Marine drugs, 2019, 17 (6), pp.1-18/319. ⟨10.3390/md17060319⟩. ⟨hal-02146552⟩