Agelas Oroidin

Oroidine (138) and its dimer mauritiamine (139) from the sponge Agelas mauritiana inhibit larval metamorphosis at ED50 values of 19 and 15 (jg/ml, whereas 4,5-dibromopyrrole-2-carbamide promotes larval metamorphosis of the ascidian Ciona savignyi at a concentration of 2.5 (jg/ml [109]. 

Tsukamoto S, Kato H, Hirota H, Fusetani N (1996) Mauritiamine, a New Antifouling Oroidin Dimer from the Marine Sponge Agelas mauritiana. J Nat Prod 59 501... 

Gautschi JT, Whitman S, Holman TR, Crews P (2004) An Analysis of Phakellin and Oroidin Structures Stimulated by Further Study of an Agelas Sponge. J Nat Prod 67 1256... 

Tsukamoto, S., Kato, H., Hirota, H., and Fusetani, N., Mauritiamine, a new antifouling oroidin dimer from the marine sponge Agelas mauritiana, J. Nat. Prod., 59, 501, 1996. 

The parent compound of this class is cyclooroidin (38), isolated from the Mediterranean sponge Agelas oroides [40]. Two syntheses of this alkaloid have been proposed [66,67], and one of them, obtaining rac-cyclooroidin by intramolecular cyclization of oroidin formate at 95 °C in protic solvents, could have biomimetic significance [67]. 

This class includes only agelastatins A-D (60-65), a family of tetracyclic oroidin derivatives isolated from Agelas dendromorpha [92,93] and Cymbastela sp. [94]. The absolute configuration of these molecules was deduced through the application of exciton-coupling techniques [93]. 

Jimenez, C., Crews, P., (1994). Mauritamide A and aceompanying oroidin alkaloids corathQspoagQ Agelas mauritiana. Tetrahedron Lett. 35, 1375-1378. 

D Ambrosio, M., Guerriero, A., Debitus, C., Ribes, O., Pusset, J., Leroy, S., Pietra, F., (1993). Agelastatin A, a new skeleton eytotoxic alkaloid of the oroidin family. Isolation from the axinellid sponge Agelas dendromorpha of the Coral Sea. J. Chem. Soc. Chem. Comm. 16, 1305-1306. 

In Fig. 9.7 are displayed acyclic and cyclic dimeric members of the pyrrole-imidazole family. Nagelamide D, from Okinawan marine sponges of the genus Agelas, is a dimer comprised of oroidin monomer units connected between the C-10 and C-15 positions [80]. However, the assigned structure of this substance is questionable (see below). Sceptrin, isolated in 1981 by Faulkner and Clardy from Agelas sceptrum, is the first reported symmetric dimer comprised of hymenidin subunits [81]. 

Gautschi, J.T., Whitman, S., Holman, T.R., and Crews, P. (2004) An analysis of phakellin and oroidin structures stimulated by firrlher study of an Agelas sponge. J. Nat. Prod., 67,1256-1261. 

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