Lissoclinum

Antitumor evaluation of cyclic peptides and macrolides from Lissoclinum 30... 

Schmidt, E.W., Nelson, J.T., Rasko, D.A. et al. (2005) Patellamide A and C biosynthesis by a microcin-like pathway in Prochloron didemni, the cyanobacterial symbiont of Lissoclinum patella. Proceedings of the National Academy of Sciences of the United States of America, 102, 7315. 

Cyclohexapept bistratamides Lissoclinum spp., Didemnidae, Ascid. from GBR and the Philippines Foster, 1992) comoramides Didemnum molle, Didemnidae from Comoro Is Rudi 1998) Oiexalpatellins Lissoclinum sp. from Fiji Is. Carroll 1996). 

Bodoi, C.D.J. Pattenden, G. (2000) Total syntheses and re-assignment of configurations of the cyclopeptides lissoclinamide and lissoclinamide 5 from Lissoclinum patella. J. Ch n. Soc., Perkin Trans. 1, 875-82. 

Carroll, A.R. Coll, J.C. Bourne, D.J. Macleod, J.K. Zabriskie, T.M. Ireland, C.M. Bowden, B.F. (1996) Patellins 1-6 and trunkamide A novel cyclic hexa-, hepta- and octa-peptides from colonial ascidians, Lissoclinum sp. Aust. J. Chem., 49, 659-67. 

Foster, M.P. Conception, G.P. Caraan, G.B. Ireland, C.M. (1992) Bistratamides C and D. Two new oxazole-containing cyclic hexapeptides isolated from a Philippine Lissoclinum bistratum ascidian. J. Org. Chem., 57, 6671-5. 

Searle, P.A. Molinslg, T.F. (1994B) Five new alkaloids from the tropical ascidian, Lissoclinum sp. J. Org. Chem., 59, 6600-5. 

Lissoclinum species of tunicates produce a range of cyclic peptides, which contain thiazole, thiazoline and oxazoline rings. Most belong to the general families patellamides (octapeptides), lissoclinamides (heptapeptides) or bistratamides (hexapeptides) [22],... 

The heptapeptide ulicyclamide (15) and the octapeptide ulithiacyclamide (16) were the first representatives of a series of cyclic peptides to be isolated from Lissoclinum patella. Their structures were elucidated by interpretation of spectral data [44], A revised structure was later put forward for ulicyclamide (15) as a result of a detailed analysis of the fast atom bombardment (FAB) mass spectrum. The same paper reported the isolation of two more polar cyclic peptides and another, which was present as a minor component. These heptapeptides were called lissoclinamides 1-3 (17-19) [45]. An unidentified tunicate from the Great Barrier Reef contained ulithiacyclamide (16) and ascidiacyclamide (14) [46]. Two syntheses of ulithiacyclamide (16)... 

L. patella from Fiji contained patellins 1-5 (50-54) [82] and earlier, solution- and solid-state conformational studies were carried out on patellin 2 (51), and the structure was determined by X-ray analysis [83]. A Lissoclinum sp. from the Great Barrier Reef yielded patellins 3 (52), 5 (54) and 6 (55) and the heptapeptide trunkamide A (56) [82]. Compounds 50-56 were all identified by interpretation of spectral data and through use of Marfey s method to determine the absolute stereochemistry of the constituent amino acids [82]. A total synthesis of the proposed structure of trunkamide A (56) revealed that the structure... 

Solution- and solid-state conformations of tawicyclamides A (57) and B (58), proline-containing cyclic peptides from a Philippines specimen of L. patella, were determined by spectroscopic and X-ray analyses respectively [87]. Patellins 1-6 (50-55), trunkamide A (56) and the tawicyclamides A-B (57-58) all lack the oxazoline ring present in most other cyclic peptides isolated from the Lissoclinum genus [22]. 

Varacin (114), a cytotoxic compound closely related to lissoclinotoxin A (106), was isolated from a Fijian sample of L vareau and a benzopentathiepin structure was proposed on the basis of spectral data [131]. Two total syntheses of varacin (114) have been carried out [132,133] and later, further syntheses were described [134-135]. N,N-dimethyl-5-(methylthio)varacin (115) and the corresponding trithiane (116) were obtained from L. japonicum from Palau and 3,4-desmethylvaracin (117) was isolated from a Eudistoma sp. from Pohnpei [136], An inseparable mixture of 5-(methylthio)varacin (118) and the corresponding trithiane (119) was obtained from a Pohnpeian Lissoclinum sp. [136]. Three additional antimicrobial polysulfides of the varacin family (120-122) were isolated from Polycitor sp., collected by dredging in the Sea of Japan [137]. 

A sulfone (636) is a minor constituent of the Mediterranean sponge Anchinoe tenacior [502]. Sulfolane (637), a familiar industrial chemical, was isolated from a mixture of the sponge Batzella sp. and a Lissoclinum tunicate from Victoria, Australia [503]. It is possibly an absorbed compound rather than a natural product [12]. 

Dichlorolissoclimide (56), a naturally occurring succinimide from the New Caledonia ascidian Lissoclinum voeltzkowi, is cytotoxic to KB cells (IC50 14 ng/ml) and P-388 cells (IC50 1 ng/ml) [56]. 

A series of sulfur-containing dopamine-derived metabolites has been isolated from tunicates, predominantly belonging to the genus Lissoclinum. 

The thiazoline and thiazole rings are present in many cyclic peptides isolated from marine organisms. Most of these types of compound have been isolated from tunicates belonging to the Lissoclinum and Didemnum genus, from sponges of the genus Theonella, and from the sea hare mollusc Dolabella auricularia. The isolation of closely related compounds from cyanobacteria pointed out the symbiont origin of these metabolites. 

The patellins 1-6 (382-387) and trunkamide A (388) [298, 299] along with tawicyclamides A (389) and B (390) [300] represent another variation of the cyclic peptides produced by Lissoclinum species. All of these compounds lack the characteristic oxazoline ring present in most Lissoclinum cyclic peptides. Compounds 382-386 and 388 were inactive in a series of in vitro cytotoxicity assays while 387, 389, and 390 showed modest cytotoxicity, supporting the importance of the presence of the oxazoline ring for cytotoxic activity [298, 300],... 

A series of macrolides bearing a thiazole moiety have been isolated from tunicates and sponges. The tunicate Lissoclinum patella has afforded the patellazoles A-C (428-430), which were found to be potent cytotoxins in the NCI human cell line protocol with mean IC50 values of 10-3—10-6 pg/ml as well as exhibiting antifungal activity [334, 335]. Furthermore, patellazole B (429) exhibited very potent antiviral activity against Herpes symplex viruses [334],... 

For a recent review of Lissoclinum peptides, see Wipf, P. In Alkaloids Chemical and Biological Perspectives-, Pelletier, S. W. Ed. Pergamon. New York 1998 pp. 187-228. 

The ascidian Lissoclinum japonicum from Palau contained the antimicrobial and antifungal metabolites N,N-dimethyl-5-(methylthio)varacin and 3,4-dimethoxy-6-(2 -iV,./V-dimethylaminoethyl)-5-(methylthio)benzotrithiane, both of which were isolated as the trifluoroacetate salts <1994T12785>. They selectively inhibit protein kinase. Also, varacin and three new antimicrobial marine polysulfides, varacins A-C, were isolated from the Far Eastern ascidian Polycitor sp. <1995JNP254>, extracted from the New Zealand ascidian Lissoclinum notti <2002T9779>. 

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