Cyanobacteria, marine

Indium-mediated allylation of an unreactive halide with an aldehyde132 was used to synthesize an advanced intermediate in the synthesis of antillatoxin,133 a marine cyanobacteria (Lyngbya majus-cula) that is one of the most ichthyotoxic compounds isolated from a marine plant to date. In the presence of a lanthanide triflate, the indium-mediated allylation of Z-2-bromocrotyl chloride and aldehyde in saturated NH4C1 under sonication yielded the desired advanced intermediate as a 1 1 mixture of diastereomers in 70% yield. Loh et al.134 then changed the halide compound to methyl (Z)-2-(bromomethyl)-2-butenoate and coupled it with aldehyde under the same conditions to yield the desired homoallylic alcohol in 80% yield with a high 93 7 syn anti selectivity (Eq. 8.55). 

Moffett, J. W. and Brand, L. E. (1996). Production of strong, extracellular Cu chelators by marine cyanobacteria in response to Cu stress, Limnol. Oceanogr., 41, 388-395. 

Tan LT (2007) Bioactive natural products from marine cyanobacteria for drug discovery. Phytochem 68 954-979... 

Nagle DG, Paul VJ (1999) Production of secondary metabolites by filamentous tropical marine cyanobacteria ecological functions of the compounds. J Phycol 35 1412-1421 Nagle DG, Camacho FT, Paul VJ (1998) Dietary preferences of the opisthobranch mollusc Stylocheilus longicauda for secondary metabolites produced by the tropical cyanobacterium Lyngbya majuscula. Mar Biol 132 267-273... 

Andrianasolo EH, Gross H, Goeger D, Musafija-Girt M, McPhail KP, Leal RM, Mooberry SL, Gerwick WH (2005) Isolation of swinholide A and related glycosylated derivatives from two field collections of marine cyanobacteria. Org Lett 7 1375-1378... 

The nonprotein amino acid /3-A -methylamino-L-alanine (BMAA) is a neurotoxin found in various species of marine cyanobacteria. This nonprotein amino acid occurs both as a free amino acid and bound to proteins.Siderophores are secondary metabolites generally produced by bacteria under iron-deficient conditions. These molecules sequester and transport ferric ion via active transport in bacteria. Some known siderophores are nonribosomal peptides that contain nonprotein amino acids with terminal amines or hydroxylamine side chains, such as exochelin Many of the known nonprotein amino... 

Freshwater cyanobacteria blooms implicated in human and livestock intoxications have been extensively studied. And they have become a serious health problem in recent years. Blooms of marine cyanobacteria are also becoming an increasingly familiar occurrence within the tropical and subtropical regions of the world. Several systematic surveys within Europe and the USA have concluded that the two most commonly isolated groups of cyanotoxins are the alkaloids-neurotoxins and the cyclic peptide hepato-toxins, both of which are destructive to liver cells. Several genera... 

Marine cyanobacteria continue to be an exceptionally rich source... 

One of the most toxic genera of marine cyanobacteria is Lyngbya — filamentous cyanobacteria within tropical and subtropical waters. Lyngbya... 

Alkaloid chemistry marine cyanobacteria, 57, 86 (2001) synthetic studies, 50, 377 (1998)... 

The teleocidins from terrestrial actinomycetales and the lyngbyatoxins from marine cyanobacteria (Chart 8.3.P) are peptide alkaloids well known for their tumor promoting ability. 

Cyanobacteria are photosynthetic prokaryotes that are widely distributed throughout marine and terrestrial environments. Members of the marine cyanobacteria genus Lyngbya are known to produce structurally interesting and biologically active secondary metabolites. Typically, linear/cyclic peptides and depsipeptides that include various nonproteinogenic amino acids are the major groups of these metabolites (Fig. 10.11), which can exhibit potent cytotoxicity. 

Maru, N., Ohno, O., and Uemura, D. (2010c). Lyngbyacyclamides A and B, novel cytotoxic peptides from marine cyanobacteria Lyngbya sp. Tetrahedron Lett. 51,6384-6387. 

Although terrestrial cyanobacteria are well-recognized producers of a wide range of bioactive compounds, marine species have received less attention until recently [159]. One of the most abundant and studied marine cyanobacteria is the pantropic Lyngbya majuscula (Oscillatoriaceae). A prolific producer of metabolites, it has so far yielded more than 110 secondary metabolites including compounds that exhibit antiproliferative, immunosuppressants, antifeedant and molluscidal activities [159,160]. Shallow water varieties of the cyanophyte contain N-substituted amides of 75-methoxytetradec-4E-enoic acid and of 7S-methoxy-9-methylhexa-dec-4 -enoic acid called malyngamides, a sub-class of which contains the 4-methoxy-3-pyrrolin-2-one system [158]. 

Burja AM, Banaigs B, Abou-Mansour E, Burgess JG, Wright PC (2001) Marine Cyanobacteria - A Prolific Source of Natural Products. Tetrahedron 57 9347... 

Gerwick WH, Tan LT, Sitachitta N (2001) Nitrogen-Containing Metabolites from Marine Cyanobacteria. In Cordell GA (ed) The Alkaloids, vol 57. Academic, San Diego, p 75... 

Tan LT (2007) Bioactive Natural Products from Marine Cyanobacteria for Drug Discovery. Phytochemistry 68 954... 

Sellner, K.G., Trophodynamics of marine cyanobacteria blooms, in Marine Pelagic Cyanobacteria Trichodesmium and other Diazotrophs, Carpenter, E.J., Ed., Kluwer Academic Press, Netherlands, 1992, 75. 

FIGURE 6.1 Examples of secondary metabolites from marine cyanobacteria. 

Dolastatins 11, 12 79, 81, first isolated from the sea hare Dolahdla auricularia and now clearly considered to be of dietary cyanobacterial origin, can be mentioned as examples [133]. The structurally closely related cyclodepsipeptide majuscula-mide C 80 has been isolated from defined cyanobacterial sources [119]. This was one and a half decades before dolastatin 12 81 was furthermore detected in extracts from a marine cyanobacteria assemblage (Lyngbya majuscula/ Schizothrix calcicola)... 

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