title: New and known diketopiperazines from the Caribbean sponge, Calyx cf. podatypa.
abstract: The cyanobacteria-containing Caribbean sponge, Calyx cf. podatypa, was collected from three sites in the Bahamas. In each of the three collections, a polar solvent partition fraction contained six known compounds including five diketopiperazines [1-4,6] and phenylacetic acid, along with a new diketopiperazine, cyclo-(4-methyl-R-proline-S-norvaline) [5]. Interestingly, all six diketopiperazines are proline-derived cyclic dipeptides. This is the first example for this class of peptide derivative to be isolated from a Calyx sponge. Parallel studies of one of the sponge collections in which the ectosome (cyanobacteria-rich) was separated from the endosome (no cyanobacteria) revealed no significant differences in their content of diketopiperazines.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Santa Cruz 95064, USA.
authors.forename: M
authors.initials: M
authors.lastname: Adamczeski
authors.forename: A R
authors.initials: AR
authors.lastname: Reed
authors.forename: P
authors.initials: P
authors.lastname: Crews
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001444:Bahamas; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009904:Optical Rotation; D010879:Piperazines / Q000737:chemistry* / Q000302:isolation & purification; D011161:Porifera / Q000737:chemistry*
chemical_list: D010879:Piperazines