Celenamides A and B, Linear Peptide Alkaloids from the Sponge Cliona celata

Article abstract of DOI:10.1021/jo01306a029

Two novel linear peptide alkaloids have been isolated as their hexaacetyl derivatives from acetylated methanol extracts of the sponge Cliona celata.The structures of hexaacetylcelenamide A (3) and B (4) were established by spectroscopic analysis and chemical degradation by ozonolysis and acid-catalyzed hydrolysis.The unique amino acid α,β-didehydro-3,4,5-trihydroxyphenylalanine was shown to be a subunit of both 3 and 4.A small-scale isolation employing acetic-d6 anhydride as the acetylating agent indicated that celenamides A (1) and B (2) were the naturally occurring sponge metabolites.