AMINO-ACID DERIVATIVES FROM THE MARINE SPONGE JASPIS-DIGONOXEA

Six heterocycles, bengamide A [1], bengamide B [2], cyclo(L-trans-(4-h ydroxyprolinyl)-L-phenylalanine) [4], the functionalized nonene lacton e 5, the novel digonazole [6], and cyclo(L-prolinyl-L-tyrosine) [7], p reviously unreported from marine origin, have been isolated from the S outh African sponge Jaspis digonoxea. The structures of the known comp ounds and the new digonazole [6] were elucidated primarily by nmr spec troscopy.