title: Lophocladines, bioactive alkaloids from the red alga Lophocladia sp.
abstract: Lophocladines A (1) and B (2), two 2,7-naphthyridine alkaloids, were isolated from the marine red alga Lophocladiasp. collected in the Fijian Islands. Their structures were deduced on the basis of high-resolution mass spectra and one- and two-dimensional NMR spectroscopy. Lophocladine A (1) displayed affinity for NMDA receptors and was found to be a delta-opioid receptor antagonist, whereas lophocladine B (2) exhibited cytotoxicity to NCI-H460 human lung tumor and MDA-MB-435 breast cancer cell lines. Immunofluorescence studies indicated that the cytotoxicity of lophocladine B (2) was correlated with microtubule inhibition. This is the first reported occurrence of alkaloids based on a 2,7-naphthyridine skeleton from red algae.
authors.affiliation: Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography and Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California at San Diego, La Jolla, CA 92093-0212, USA.
authors.forename: Harald
authors.initials: H
authors.lastname: Gross
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Goeger
authors.forename: Patrice
authors.initials: P
authors.lastname: Hills
authors.forename: Susan L
authors.initials: SL
authors.lastname: Mooberry
authors.forename: David L
authors.initials: DL
authors.lastname: Ballantine
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Murray
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Valeriote
authors.forename: William H
authors.initials: WH
authors.lastname: Gerwick
mesh_terms: D000470:Alkaloids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D000970:Antineoplastic Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D004354:Drug Screening Assays, Antitumor; D005260:Female; D005367:Fiji; D006801:Humans; D015394:Molecular Structure; D009287:Naphthyridines / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D019906:Nuclear Magnetic Resonance, Biomolecular; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects; D017465:Receptors, Opioid, delta / Q000037:antagonists & inhibitors; D000461:Rhodophyta / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D000970:Antineoplastic Agents; D009287:Naphthyridines; D016194:Receptors, N-Methyl-D-Aspartate; D017465:Receptors, Opioid, delta; C510708:lophocladine A; C510709:lophocladine B