Flustra foliacea

Evidence has accumulated that inhibition of QS is a strategy commonly adopted by eukaryotic organisms to combat potentially pathogenic bacteria. The production of AHL antagonists has been demonstrated for the marine red alga Delisea pulchra [68], higher plants [85] as well as the animal Flustra foliacea [ 127]. Compounds with QS-inhibiting activity have been obtained from D. pulchra and F. foliacea (Fig. 5) while the structures of the plant-derived substances have yet to be elucidated. 

Peters, L Wright, A. D Krick, A. and Koning, G. M. 2004. Variation of bromi-nated indoles and terpenoids within single and different colonies of the marine bryozoan Flustra foliacea. Journal of Chemical Ecology, 30 1165-1181. 

Several new brominated tryptamines and tryptophans have been described. The Tasmanian bryozoan Amathia convoluta contains convolutindole A (1342) (1319), and the North Sea bryozoan Flustra foliacea (Fig. 3.19) has afforded deformylflustrabromine B (1343) (1320), 1344, 1345, and deformylflustrabromine... 

Peters L, Wright AD, Kehraus S, Giindisch D, Tilotta MC, Konig GM (2004) Prenylated Indole Alkaloids from Flustra foliacea with Subtype Specific Binding on NAChRs. Planta Med 70 883... 

Peters L, Konig GM, Terlau H, Wright AD (2002) Four New Bromotryptamine Derivatives from the Marine Bryozoan Flustra foliacea. J Nat Prod 65 1633... 

Sala F, Mulet J, Reddy KP, Bernal JA, Wikman P, Valor LM, Peters L, Kdnig GM, Criado M, Sala S (2005) Potentiation of Human a4p2 Neuronal Nicotinic Receptors by a Flustra foliacea Metabolite. Neurosci Lett 373 144... 

Flustra foliacea L., a marine bryozoan, or moss animal, contains29 two isomeric metabolites, flustramine A and flustramine B, which are eserine derivatives that contain one bromine and two isoprenyl substituents, at positions 6, 3a, and 8. In... 

Several of the alkaloids from bryozoans can be considered to be indoles—Amathla alternata and Zoobotryon vertlcillatum contain simple indoles while Chartella papyracea, Flustra foliacea and Hinckstnojlus-tra denticulata give rise to more complex polycyclic compounds. 

Simple quinolines and quinolin-4-ones often occur outside of the Rutacae plant family, thus the brominated quinoline (1) is metabolised by the marine bryozoan Flustra foliacea (P. Wulff, J.S. Carle and C. Christophersen, Comp.Biochem.Physiol.B, 1982, 71, 525) and an unusual... 

The marine bryozoan Flustra foliacea collected in the North Sea has given rise to the isolation of a complicated mixture of alkaloids, twelve of which have so far been identified (32-36). The structures are depicted in Scheme 11 flustramine A (1)... 

Scheme 11. Alkaloids from the marine bryozoan Flustra foliacea. Structures numbered in Arabic originate from specimens from the North Sea and those with Roman numbers are from Canadian specimens. Flustrabromine (11) and 6-bromo-/Vb-methyl-/Vb-formyl-tryptamine (10) were isolated as an intimate mixture of Z and E geometrical isomers. The formulas are not intended to depict absolute stereochemistry.

Other comparable examples are known. The main alkaloid in a Nova Scotia collection of Flustra foliacea, dihydroflustramine C, is related to pseudophrynaminol from the skin of the myobatrachid burrowing frog Pseudophryne coriacea. Both classes of alkaloids are based on the 3a-prenyl pyrrolo[2,3- >]indole skeleton (31). 

One of two new alkaloids isolated from the marine bryozoan Flustra foliacea proves to be 6-bromo-Nj -formyl-Nj -methyl-... 

Iminium organocatalysis was key to the enantioselective total synthesis of (—)-flustramine B (157) from the marine bryozoan Flustra foliacea by MacMillan and co-workers (Scheme 31) [137], which is discussed here despite not incorporating the entire C5 unit in one step. On treatment of the Boc-protected... 

The discovery of 2-ferf-prenylated deformylflustrabromine (235) as a major metabolite of Flustra foliacea collected near Helgoland [182-184] prompted us to investigate its presumably biomimetic conversion to the pyrrolo[2,3-b]indole flustramine C (236) [185], which is ferf-prenylated at the bridgehead C3a (Scheme 45). For the synthesis of deformylflustrabromine (235), Wb-methyltryptamine (232) was converted to Wb-formyl-Wb-methyltryptamine which cleanly underwent... 

The bryozoon Flustra foliacea contains bromoindole alkaloids ( bryozoan alkaloids) with the physostig-mine skeleton this is also characteristic for a group of alkaloids from the calabar bean Physostigma veneno-sum) F. A, Cj.HjsBrN, Mr 389.38 F B, CjiHjsBrNj, Mr 389.38. 

Rhizopus, Penicilliurn, Claviceps purpurea (with Secale cereale) Pseudomonas tabaci Pseudomonas aeruginosa Flustra foliacea... 

From North Sea Bryozoan Flustra foliacea) several, brominated indole alkaloids have been isolated. These include deformylflustramine and flustramine. Deformylfrustrabromine A and deformylfrustrabromine B... 

The bryozoans (moss animals or sea mats) responsible for contact dermatitis are mainly Alcyonidium gela-tinosum, A. hirsutum, A. topsenti, Flustra foliacea and Electra pilosa (Bonnevie 1948 Audebert and Lam-oureux 1978 Jeanmougin et al. 1983, 1987)- A- g l -tinosum is widespread in the Northern hemisphere and, in particular, in the Atlantic, the Baltic, the North Sea, the Arctic and the Channel. 

Marine Alkaloids. 3. Bromo-Substituted Alkaloids from the Marine Bryozoan Flustra foliacea, Flustramine C and Flustraminol A and B. J. Org. Chem. 46, 3440 (1981). 

WuLFF, P., J.S. Carle, and C. Christophersen Marine Alkaloids. Part 4. A Form-amide, Flustrabromine, from the Marine Bryozoan Flustra foliacea. J. Chem. Soc., Perkin Trans. I 1981, 2895. 

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