From Indo-Pacific marine

In this chapter, a rationale of the structure-activity relationships of various series of bioactive secondary metabolites from Indo-Pacific marine invertebrates is reviewed. These include alkaloids, terpenes and polybrominated diphenyl ethers which were subjected to a series of bioassays in search for insecticidal, antibacterial, fungicidal, and cytotoxic lead compounds. From these various biotests, it was observed that the bioactivity of an analogue is not due to general toxicity but rather possesses a degree of specificity on a particular target biomolecule. The relationship between chemical structures and biological activity is related to the specific action of a compound. 

Table 5. Bioactivity of Metabolites Isolated from Indo-Pacific Marine Invertebrates...

Proksch, P., Ebel, R., Edrada, R.A., Schupp, P., Lin, W.H., Wray, S.V., and Steube, K. (2003a) Detection of pharmacologically active natural products using ecology selected examples from Indo-Pacific marine invertebrates and sponge-derived fungi. PureAppl. Chem., 75, 343-352. 

STRUCTURE-ACTIVITY RELATIONSHIPS OF BIO ACTIVE METABOLITES FROM SOME INDO-PACIFIC MARINE INVERTEBRATES... 

Isol. from the Indo-Pacific marine sponge Penares sollasi. Protein kinase C inhibitor, [ot] —16.9 (c, 0.04 in MeOH). 

Pettit, G.R. etal. Antineoplastic agents. 520. Isolation and structure of irciniastatins A and B from the Indo-Pacific marine sponge Ircinia ramosa. J. Med. Chem. 47, 1149-1152(2004). 

Prialt [Fig. 6] is a synthetic copy of a toxin from the Magician s cone snail. Conus magus, a mollusk from the Indo-Pacific region. This is also one of the first pharmaceuticals that demonstrate the promise that marine life, particularly invertebrates, holds for drug developers. 

High values of the specific skeletal complexity S/H are observed for isoprenoids from temperate land and alkaloids from both the eastern tropical land and the Indo-Pacific biogeographic marine area, or present both in the sea and on land (Fig. 11.2C). Comparing such a huge area as the temperate land with more restricted biomes is difficult. However, it emerges clearly that the average specific skeletal complexity (S/H)a (Fig. 11.2D) is high for the alkaloids from any ecosystem. Fossil... 

A study of South Pacific marine invertebrates has revealed the new 1891 in the sponge Dysidea herbacea (1760). The new 1892 was isolated from Sagaminop-teron bilealbum molluscs feeding on the sponge Dysidea herbacea from Guam waters (1761). Four samples of Dysidea sponges from the Indo-Pacific yielded the... 

Levels of POPs in two local marine mammals, the Indo-Pacific humpback dolphin (Sousa chinensis) and Unless porpoise (Neophocaena phocaenoides), were measured in two ad hoc studies of stranded cetaceans in 1995-2000 and 2000-2001, respectively (Jefferson et al., 2002 Imanishi et al., 2004). Cetacean tissue samples were collected from stranded animals found in Hong Kong and analyzed for DDT, mirex, toxaphene and PCBs. High mean blubber concentrations of DDT (32.8 mg kg-1 ww) and PCBs (8.19 mg kg-1 ww) were reported. 

Heliannuol A (7) is the first heliannane reported in the literature.27 It was isolated from sunflower leaves and all the following members of the family have been isolated from the same source, but in different sunflower varieties. Surprisingly, no heliannuols have been isolated from other terrestrial sources so far. However, the basic heliannane skeleton (6) has been isolated lately from a marine organism, the Indo-Pacific sponge Haliclona fascigera.8 Heliannanes isolated from different sources are summarized in Table 5.1 and Figure 5.2 new heliannanes have been isolated from other sunflower varieties (unpublished results). 

About three years ago, our laboratory started a screening program for new insecticidal constituents from marine organisms especially from the Indo-Pacific locality [10]. Approximately 200 different extracts were tested for insecticidal activity against the polyphagous pest insect Spodoptera littoralis, a serious pest on important crops such as cotton and tomatoes [11, 12, 13]. The larvae of this pest insect are reared in the... 

The SIO-RU-SKB collaboration also involved the collection, in 1994 and 1995, of over 100 marine invertebrates from the Ponto do Ouro area of southern Mozambique, about 80kms north of Sodwana Bay Fig. (1). Two cyclic peptides, the known swinholide A (78) and the new bicyclic theopalauamide (79), were isolated from Mozambique specimens of the Indo-Pacific lithistid sponge Theonella swinhoei (Family Theonellidae) [79]. Interestingly, a concurrent investigation of T. swinhoei from Palau,... 

Kelecom, a., B. Tursch, and M. Vanhaelen Chemical Studies of Marine Invertebrates XIX. Glycosidic Chain Structure of Thelothurins A and B, Two New Saponins from the Indo-Pacific Sea Cucumber Thelenota ananas Jaeger (Echinodermata). Bull. Soc. Chim. Belg. 85, 277 (1976). 

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