Amino acid derivatives from the marine sponge Jaspis digonoxea

Six heterocycles, bengamide A [1], bengamide B [2], cyclo(L-trans-(4-hydroxyprolinyl)-L-phenylalanine) [4], the functionalized nonene lactone 5, the novel digonazole [6] and cyclo(L-prolinyl-L-tyrosine) [7], previously unreported from marine origin have been isolated from the South African sponge Jaspis digonoxea. The structures of the known compounds and the new digonazole [6] were elucidated primarily by nmr spectroscopy.