Agelasine
Agelasines are 7,9-dialkylpurinium salts isolated from marine sponges (Agelas sp.). They are considered secondary metabolites. Their contribution to the sponge is assumed to be some sort of protection against microorganisms. At the present time a total of eleven 9-methyladeninium salts, agelasine A–I, epiagelasine C and agelin B, are known.H. Nakamura, H. Wu, Y. Ohizumi and Y. Hirata, Tetrahedron Lett., 1984, 25, 2989H. Wu, H. Nakamura, J. Kobayashi and Y. Ohizumi, Tetrahedron Lett., 1984, 25, 3719R. J. Capon and D. J. Faulkner, J. Am. Chem. Soc., 1984, 106, 1819H. Wu, H. Nakamura, J. Kobayashi, M. Kobayashi, Y. Ohizumi and Y. Hirata, Bull. Chem. Soc. Jpn., 1986, 59, 2495K. Ishida, M. Ishibashi, H. Shigemori, T. Sasaki and J. Kobayashi, Chem. Pharm. Bull., 1992, 40, 766T. Hattori, K. Adachi and Y. Shizuri, J. Nat. Prod., 1997, 60, 411X. Fu, F. J. Schmitz, R. S. Tanner and M. Kelly-Borges, J. Nat. Prod., 1998, 61, 548 All compounds carry a diterpenoid side chain in the adenine 7-position. The agelasines are closely related in structure with the agelasimines.
Chemists have reproduced (−)-agelasine A,E. Piers, M. L. Livain, Y. Han, G. L. Plourde, L. Guy and W.-L. Yeh, J. Chem. Soc., Perkin Trans. 1, 1995, 963 (−)-agelasine B,E. Piers and J. Y. Roberge, Tetrahedron Lett., 1992, 33, 6923; (b) H. Iio, K. Asao and T. Tokoroyama, J. Chem. Soc., Chem. Commun., 1985, 774 (−)-agelasine E,A. K. Bakkestuen, L.-L. Gundersen, D. Petersen, B. Utenova and A. Vik, Org. Biomol. Chem., 2005, 3, 1025 (−)-agelasine F,K. Asao, H. Iio and T. Tokoroyama, Tetrahedron Lett., 1989, 30, 6401 and (+)-agelasine DB. T. Utenova and L.-L. Gundersen, Tetrahedron Lett., 2004, 45, 4233 by organic synthesis.
Agelasines are associated with bioactivities such as antimicrobial and cytotoxic effects, as well as contractive responses of smooth muscles and inhibition of Na/K-ATPase (NaKATPase). Furthermore, in vitro activity against Mycobacterium tuberculosis is reported for agelasine F.G. C. Mangalindan, M. T. Talaue, L. J. Cruz, S. G. Franzblau, L. B. Adams, A. D. Richardson, C. M. Ireland and G. P. Conception, Planta Med., 2000, 66, 364