Aplidium

Macrocarbocyclic longithorone A (Aplidium longithorax Monniot, 1987, Aplousobranchia, Ascid. from Palau Fu 1997 and GBR Davis 1999B). 

Aikal. indole meridianins (Aplidium meridianum (Sluitw, 1906), Polyclinidae, Ascid. from Atlantic Antarctica, depth 100m Franco 1998) psammopmmins (Psammopemma sp., Poecil. fitmi Indian Antarctica, depth 258m Butler 1992A). 

Carroll, A.R. Bowden, B.F. Coll, J.C. (1993) Novel cytotoxic iodotyrosine-based alkaloids from colonial ascidians, Aplidium sp. Aust. J. Chem., 46, 825-32. 

Fu, X. Hossain, M.B. Schmitz, F.J. van der Helm, D. (1997) Longithorones, unique prenylated para- and metacyclophane type quinones from the tunicate Aplidium longithorax. J. Org. Chem., 62, 3810-19. 

Uoamines A (172) and B (173) are piperidine alkaloids, isolated from Aplidium uouo from Maui, Hawaii. They differ only in the geometry of the 3-thiomethylacrylate ester group [168]. 

Meridianins, brominated indole alkaloids from the tunicate Aplidium meridianum, show cytotoxicity against LMM3 (murine mamarian adenocarcinoma cell line) with IC5o values of 11.4 jM for meridianin B (25), 9.3 iM for meridianin C (26), 33.9 iM for meridianin D (27), and 11.1 aM for meridianin E (28) [41]. 

Other miscellanous thiazole-containing metabolites were obtained from a variety of marine organisms. Compounds 448 and 449 were isolated from the tunicate Aplidium pliciferum and their structures were established from spectral data and confirmed by synthesis [349]. Very few secondary metabolites have been reported from hydroids. The thiazole tridentatol C... 

An Antarctica collection of the sponge Psammopemma sp. has yielded the new 4-hydroxyindole alkaloids, psammopemmins A (1378), B (1379), and C (1380), which embody the unique 2-bromopyrimidine unit (1337). The related meridia-nins B (1381), C (1382), D (1383), E (1384), and F (1385) were found in the tunicate Aplidium meridianum collected at 100 m near the South Georgia Islands (1338,1339). These protein kinase inhibitors have been synthesized (1340). The sponge Discodermia polydiscus has afforded 6-hydroxydiscodermindole (1386) (1341). 

Fig. 3.21 This Indonesian ascidian Aplidium sp. produces the novel metacyclophane floresolide C (1616) (Photo J. Tanaka)...

Fig. 3.27 Aplidium longithorax, a tunicate that produces polybrominated diphenyl ethers (Photo F. J. Schmitz)...

Marine tunicates are also a source of brominated tyrosine derivatives. The colonial ascidian Aplidium sp., which was collected in Australia, yielded the novel iodinated tyrosine alkaloids 1973-1975 (1819). Collections of Botryllus sp. and Botryllus schlosseri from the Philippines and the Great Barrier Reef, respectively, have afforded botryllamides A-D (1976-1979) (1820). A Palauan ascidian Botrylloides tyreum produces several new botryllamides, including the brominated botryllamide G (1980) (1821). The simple brominated tyramines 1981 and 1982 were isolated from the New Zealand ascidian Cnemidocarpa bicornuta (1822) and an Indonesian Eudistoma sp. ascidian (1823). 

Hernandez Franco L, Bal de Kier Joffe E, Puricelli L, Tatian M, Seldes AM, Palermo JA (1998) Indole Alkaloids from the Tunicate Aplidium meridianum. J Nat Prod 61 1130... 

Reyes F, Fernandez R, Rodriguez A, Francesch A, Taboada S, Avila C, Cuevas C (2008) Aplicyanins A-F, New Cytotoxic Bromoindole Derivatives from the Marine Tunicate Aplidium cyaneum. Tetrahedron 64 5119... 

Issa HH, Tanaka J, Rachmat R, Higa T (2003) Floresolides, New Metacyclophane Hydro-quinone Lactones from an Ascidian, Aplidium sp. Tetrahedron Lett 44 1243... 

Fu X, Hossian MB, Schmitz FJ, van der Helm D (1997) Longithorones, Unique Prenylated Para- and Metacyclophane Type Quinones from the Tunicate Aplidium longithorax. J Org Chem 62 3810... 

Carroll AR, Bowden BJ, Coll JC (1993) Studies of Australian Ascidians. II Novel Cytotoxic Iodotyrosine-Based Alkaloids from Colonial Ascidians, Aplidium sp. Aust J Chem 46 825... 

Methyl-2 -deoxycytidine (437) and 3-methyl-2 -deoxyuridine (438) were isolated from the Swedish sponge Geodia baretti. Compound 437 exhibits strong contractile activity in the isolated guinea pig ileum assay, whereas 438 had no effect on contractions (356). Thymidine-5 -carboxylic acid (439) and 2 -deoxyuridine-5 -carboxylic acid (440), which were previously known only as synthetic products, were found in extracts of the ascidian Aplidium fuscum of the East Pyrenean coast (357). 

Next, Schmitz and co-workers119 reported the characterization of a pair of novel prenylated paracyclophanes and metacyclophane-type hydroquinones from the tunicate Aplidium longithorax. Complete H and 13C resonance assignments were made for these complex natural products, again employing 3 mm micro-probe technology. The structure of longitorhol-A (56) is shown. 

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