Lissoclinum patella ascidiacyclamide from

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)... 

Van den Brenk, A.L, Fairhe, D.P., Gahan, L.R., Hanson, G.R., and Hambley, TW. (1996) A novel potassium-binding hydrolysis product of ascidiacyclamide a cyclic octapeptide isolated from the ascidian Lissoclinum patella. Inorg. Chem., 35,1095—1100. 

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