On the first polyarsenic organic compound from nature : Arsenicin A from the New Caledonian marine sponge Echinochalina bargibanti Mancini, I. Guella, G. Frostin, M. Hnawia, E. /Laurent, Dominique /Debitus, Cécile Pietra, F. ab initio calculations antibiotics arsenic mass spectrometry natural products Reported here is the first polyarsenic compound ever found in nature. Denominated arsenicin A, it was isolated along a bioassay-guided fractionation of the organic extract of the poecilosclerid sponge Echinochalina bargibanti collected from the northeastern coast of New Caledonia. In defining an adamantine-type polyarsenic structure for this compound, deceptively simple NMR spectra were complemented by extensive mass spectral analysis. However, it was only the synthesis of a model compound that provided the basis to discriminate structure 4 from other spectrally compatible structures for arsenicin A; to this end, a comparative ab initio simulation of IR spectra for the natural and the synthetic compounds was decisive. Arsenicin A is endowed with potent bactericidal and fungicidal activities on human pathogenic strains. All this may revive pharmacological interest in arsenic compounds while prompting us to rethink the arsenic cycle in nature. 2006 text https://www.documentation.ird.fr/hor/fdi:010055024 fdi:010055024 Mancini I., Guella G., Frostin M., Hnawia E., Laurent Dominique, Debitus Cécile, Pietra F.. On the first polyarsenic organic compound from nature : Arsenicin A from the New Caledonian marine sponge Echinochalina bargibanti. 2006, 12 (35), 8989-8994 EN