Halogenated Fatty Acid Amides and Cyclic Depsipeptides from an Eastern Caribbean Collection of the Cyanobacterium Lyngbya majuscula

• Published in: Journal of natural products (Washington, D.C.) Vol. 72; no. 9; pp. 1573 - 1578
• Main Authors: Jiménez, Jorge I, Vansach, Tifanie, Yoshida, Wesley Y, Sakamoto, Bryan, Pörzgen, Peter, Horgen, F. David
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society and American Society of Pharmacognosy 01.09.2009; Amer Chemical Soc; American Society of Pharmacognosy
• Subjects: Amides; Animals; Bacteriology; Biological and medical sciences; Chemistry, Medicinal; Cyanobacteria; Cyanobacteria - chemistry; Depsipeptides - chemistry; Depsipeptides - isolation & purification; Depsipeptides - pharmacology; Fatty Acids, Unsaturated - chemistry; Fatty Acids, Unsaturated - isolation & purification; Fatty Acids, Unsaturated - pharmacology; Female; Fundamental and applied biological sciences. Psychology; Grenada; Humans; Hydrocarbons, Halogenated - chemistry; Hydrocarbons, Halogenated - isolation & purification; Hydrocarbons, Halogenated - pharmacology; Kidney - cytology; Kidney - drug effects; Life Sciences & Biomedicine; Lyngbya majuscula; Microbiology; Molecular Structure; Morphology, structure, chemical composition; Nuclear Magnetic Resonance, Biomolecular; Pharmacology & Pharmacy; Plant Sciences; Science & Technology; Spodoptera - drug effects; Spodoptera exigua; Caribbean Sea; Grenada; ASW, Caribbean Sea; PEPTIDES; NATURAL-PRODUCTS; AMINO-ACIDS; MALYNGAMIDES; HECTOCHLORIN; MARINE; DERIVATIVES; CHLORINATED METABOLITE; Human; Fatty amide; Embryo; Aliphatic compound; Cyclic peptides; Toxicity; Cytotoxicity; Ketone; In vitro; Biological activity; Hexapeptide; Kidney; Marine environment; Cell line; Microbial origin; Depsipeptide; Chlorine Organic compounds; Absolute configuration; Cyanobacteria; Bacteria; Isolation; Structural analysis
• ISSN: 0163-3864; 1520-6025
• DOI: 10.1021/np900173d

A lipophilic extract of an eastern Caribbean collection of Lyngbya majuscula yielded two new halogenated fatty acid amides, grenadamides B (1) and C (2), and two new depsipeptides, itralamides A (3) and B (4), along with the known compounds hectochlorin and deacetylhectochlorin. The recently reported depsipeptide carriebowmide (5) was also present in the extract and isolated as its sulfone artifact (6). Compounds 1−4 were identified by spectroscopic methods. The configurations of the amino acid residues of 3, 4, and 6 were determined by LC-MS analyses of diastereomeric derivatives of the acid hydrolysates (advanced Marfey’s method). Based on the configurational analysis of 6, in direct comparison with authentic carriebowmide (5), a minor structural revision of 5 is proposed. Compounds 1 and 2 displayed marginal activity against the beet armyworm (Spodoptera exigua). Compounds 1−4 and 6 were assessed for general cell toxicity in human embryonic kidney (HEK293) cells. Only itralamide B (4) displayed significant cytotoxicity, showing an IC50 value of 6 ± 1 μM.