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Sixteen compounds belonging to seven distinct classes of organic compounds were isolated from a bryozoan and seven sponges; their structures were characterized by a combination of spectroscopic and chemical methods. The classes of compounds are aliphatic amino alcohols, bromotyrosine-derived peptides, a nucleoside, an alkaloid, sesquiterpenes, bromo and peroxy acids. The first chemical study of an Hawaiian bryozoan led to isolation of two new amino alcohols 30* and 31. The extract from a Pohnpei sponge, Aplysinella sp., yielded two new bromotyrosine derivatives, psammaplysins D (46) and E (47), which show antiviral and immunosuppressive activities. An unprecedented alkylated arabinonucleoside, kumusine (52), was found in an Indonesian sponge, Theonella sp. Kumusine(52) exhibited moderate immunosuppressive activity. A new manzamine, 8-hydroxymanzamine A (78), was isolated from an Indonesian sponge, Pachypellina sp.2 The compound showed cytotoxicity against tumor cells (KB and LoVo) and a virus (HSV-II). Two thiocyanates, 2-thiocyanatoneopupukeanane (84) and 4-thiocyanatoneopupukeanane (85) were found in two sponges. Both compounds possess the neopupukeanane skeleton; the rare thiocyano group was confirmed by chemical transformation to a thiol. Three unstable fatty acids, (7E,13E,15Z)-14,16-dibromo-hexadeca-7,13,15-trien-5-ynoic acid (94), (7E,9E,13E,15Z)-14,16-dibromohexadeca-7,9,13,15-tetraen-5ynoic acid (95), (5Z,7E,9E,13E,15Z)-6,14,16-tribromohexadeca-5,7,9,13,15-pentaenoic acid (96), and two epidioxy acids, epidioxymanadic acids A (105) and B (106), were purified by high speed countercurrent chromatography. Structure determination of the polybrominated acids and the epidioxy acids was carried out mainly by NMR techniques. Absolute stereochemistry of the epidioxy acids was determined on an alcohol derivative of the acid.(DIAGRAM, TABLE OR GRAPHIC OMITTED...PLEASE SEE DAI) ftn*Please refer to dissertation for diagrams. Ichiba, T.; Scheuer, P. J.; Kelly-Borges, M. J. Org. Chem. 1993, 58, 4149-4150. 2Ichiba, T.; Corgiat, M. J.; Scheuer, P. J.; Kelly-Borges, M. J. Nat. Prod. 1994, 57, 168-170. Pham, A. T.; Ichiba, T.; Yoshida, Y. W.; Scheuer, P. J.; Uchida, T.; Tanaka, J.; Higa, T. Tetrahedron Lett. 1991, 32, 4843-4846. Ichiba, T.; Scheuer, P. J.; Kelly-Borges, M. Helv. Chim. Acta 1993, 76, 2814-2816.
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