Stylissa stylissadines

The first examples of tetrameric pyrrole imidazole alkaloids, stylissadine A (100) and B, were isolated from the Caribbean sponge Stylissa carihica in 2006 [128]. They possess a symmetric dimeric stmcture derived from condensation of two massadine units, and differ in the configuration at the center C-2. Stylissadines represent the largest pyrrole-imidazole alkaloids isolated so far, and, with their 16 stereogenic centers, they are the most complex stmctures known within the oroidin alkaloid family. 

Among the more complex structures, carteramine A and stylissadines A and B are respectively dimers (C22N10) and tetramers (C44N20) of C11N5 pyrrole-imidazole alkaloids. Isolated from the species Stylissa carteri harvested in Japan, carteramine A is an inhibitor of neutrophil chemotaxis (IC50 5 pM), and may lead to a new generation of anti-... 

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