Bromopyrrole Alkaloids Isolated from the Patagonian Bryozoan Aspidostoma giganteum

PATIÑO CANO, L.; MUNIAIN, CLAUDIA; KNOTT, M. E.; PURICELLI, L.; PALERMO, J.

JOURNAL OF NATURAL PRODUCTS

AMER CHEMICAL SOC

Lugar: Washington; Año: 2014 vol. 77 p. 1170 - 1178

0163-3864

Nine new bromopyrrole alkaloids, aspidostomides A-H and aspidazide A (1-9), were isolated from the Patagonian bryozoan Aspidostoma giganteum. Aspidostomides A-H have dibromotyrosine or bromotryptophan-derived moieties forming either linear amides or pyrroloketopiperazine-type lactams with a bromopyrrole carboxylic acid as a common structural motif. On the other hand, aspidazide A is a rare asymmetric acyl azide formed by an N-N link of two different pyrroloketopiperazine lactams, and is the first isolated compound of this class from marine invertebrates. This work is the first report of secondary metabolites isolated from a bryozoan from the Patagonian region. The structures of compounds 1-9 were elucidated by spectroscopic methods and chemical transformations. One of these compounds, aspidostomide E (5) was moderately active against the 786-O renal carcinoma cell line.