title: Gymnangiamide, a cytotoxic pentapeptide from the marine hydroid Gymnangium regae.
abstract: A cytotoxic aqueous extract from the marine hydroid Gymnangium regae provided a novel linear pentapeptide, designated gymnangiamide (1). The planar structure of 1 was elucidated by interpretation of spectral data as well as chemical degradation and derivatization studies. In addition to the amino acids isoleucine and phenylserine, this peptide contained N-desmethyldolaisoleuine, O-desmethyldolaproine, and alpha-guanidino serine, three residues that have not previously been reported in a natural product. The absolute configurations of the constituent amino/guanidino acids were determined by chemical degradation and derivatization, followed by HPLC and LC-MS comparison with authentic standards. Gymnangiamide (1) was moderately cytotoxic against a number of human tumor cell lines in vitro.
authors.affiliation: Molecular Targets Development Program, Center for Cancer Research, National Cancer Institute, Building 1052, Room 121, Frederick, Maryland 21702-1201, USA.
authors.forename: Dennis J
authors.initials: DJ
authors.lastname: Milanowski
authors.forename: Kirk R
authors.initials: KR
authors.lastname: Gustafson
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Rashid
authors.forename: Lewis K
authors.initials: LK
authors.lastname: Pannell
authors.forename: James B
authors.initials: JB
authors.lastname: McMahon
authors.forename: Michael R
authors.initials: MR
authors.lastname: Boyd
mesh_terms: D000596:Amino Acids / Q000737:chemistry; D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry* / Q000494:pharmacology; D045744:Cell Line, Tumor; D002851:Chromatography, High Pressure Liquid; D004354:Drug Screening Assays, Antitumor; D008401:Gas Chromatography-Mass Spectrometry; D006146:Guanidines / Q000737:chemistry; D006801:Humans; D006829:Hydra / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D008386:Marine Biology; D013058:Mass Spectrometry; D015394:Molecular Structure; D009842:Oligopeptides / Q000737:chemistry* / Q000302:isolation & purification; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D000970:Antineoplastic Agents; D006146:Guanidines; D009842:Oligopeptides; C487670:gymnangiamid