Agelas sceptrum Sceptrin

Walker, Roger P., Faulkner, D. John, Van Engen, Donna, Clardy, Jon., (1981). Sceptrin, an antimicrobial agent from the sponge Agelas sceptrum. J. Am. Chem. Soc. 103, 6772-6773. 

In Fig. 9.7 are displayed acyclic and cyclic dimeric members of the pyrrole-imidazole family. Nagelamide D, from Okinawan marine sponges of the genus Agelas, is a dimer comprised of oroidin monomer units connected between the C-10 and C-15 positions [80]. However, the assigned structure of this substance is questionable (see below). Sceptrin, isolated in 1981 by Faulkner and Clardy from Agelas sceptrum, is the first reported symmetric dimer comprised of hymenidin subunits [81]. 

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