(-)-Agelasidine A from Agelas clathrodes.

(-)-Agelasidine A was identified from the methanol extract of the marine sponge Agelas clathrodes for the first time together with zooanemonin, 1-carboxymethylnicotinic acid, hymenidin, mukanadins A and C, monobromodispacamide, agelasidine D, 2-amide-4-bromopyrrole, O-methyltryptophan and an agelasines mixture. The structures were characterized by spectroscopic methods. (-)-Agelasidine A was tested for antibacterial and antifungal activities and shown to act as a bacteriostatic agent as it inhibited the growth of Staphylococcus aureus and partially the growth of other bacteria.