Marine bioactive compounds structures

POLYCYCLIC AMINE ALKALOIDS (3-ALKYLPIPERIDBVE ALKALOIDS) - NOVEL MARINE BIOACTIVE COMPOUNDS STRUCTURE, SYNTHESIS AND BIOCHEMICAL ASPECTS... 

Rodriguez, J. (2000) Polycyclic amine alkaloids (3-alkylpiperidine alkaloids) novel marine bioactive compounds structures, synthesis and biochemical aspects, in Studies in Natural Products Chemistry, vol. 24 (ed. Atta-ur-Rahman), Elsevier, pp. 573—681. 

Marine fishes are rich sources of structurally diverse bioactive compounds including polyunsaturated fatty acids, polysaccharides, minerals, vitamins, antioxidants, enzymes, and bioactive peptides (Kim et ah, 2008). Marine fish-derived ACE inhibitory peptides have been purified from enzymatic digestion of various fish materials from Alaska pollack (Nakajima et ah, 2009), bonito (Fujita et ah, 2000 Hideaki et ah, 1993 Yokoyama et ah,... 

Marine sponges contain a host of bioactive compounds, particularly small molecules, and also contain a range of peptides that are non-ribosomally synthesised, often containing non-native amino acids. However, there are examples of peptides of ribosomal origin, including, for example, asteropine A isolated from the sponge Asteropus simplex.133 This peptide comprises 36 residues and three disulphide bonds. It has potent sialidase inhibitory activity and thus has applications in the design of novel viral inhibitors. Structural analysis of asteropine A with NMR spectroscopy revealed a cystine-knot motif, similar to that already described for plant toxins. This observation emphasises the fact that the cystine-knot motif is extremely prevalent in disulphide-rich peptides.134 Asteropine A, discovered in 2006, was the first reported cystine-knot peptide isolated from marine invertebrates other than from cone snails, which are described in more detail below. 

This review describes bioactive compounds isolated from marine algae and invertebrates with an emphasis on then-uniqueness. Because of limited space, metabolites from bacteria, cyanobacteria, and fungi cannot be included, although some from cyanobacterial and endosymbiotic bacterial origins are described (some reviews on metabolites of marine bacteria, cyanobacteria, and fungi are provided in the Further Reading section). Structures and bioactivities are described for compounds that represent natural product classes, but steroids and carotenoids are not included. 

Over the past quarter-century more than 10,000 compounds have been reported from marine-derived organisms. These compounds encompass a wide variety of chemical structures including acetogenins, polyketides, terpenes, alkaloids, peptides and many compounds of mixed biosynthesis. A number of excellent books and reviews document the diversity of both structures and bioactivities which have been observed for marine-derived compounds. ... 

Natural Product Chemistry continues to present exciting opportunities for medicinal chemists to discover new bioactive compounds against various diseases. Even in cases where the structures are too complex to be obtained on a large scale by synthesis, the interest is often focussed on those portions of the stnictures which are responsible for the biological activity and which can serve as simpler pharmacophores for synthesis and study of structure-activity relationships. The enormous structural diversity offered by natural products of terrestrial and marine origin therefore offers a vast resource to medicinal chemists in search for new bioactivity profiles or mechanisms of actions. 

This review has used almost 263 citations and described nearly 390 new metabolites from marine microorganisms. The data implies that marine microorganisms are just the same as their terrestrial congeners on the diversity of metabolites. As an abundant source of bioactive compounds, they are not at an inferior position compared with other organisms. The unique advantages of the research in this area, the abundance, structure diversity, and biological activities, offers... 

As mentioned above, marine dinoflagellates are considered rich resources of bioactive compounds, and various long-carbon-chain polyol compounds have been isolated from cultured symbiotic ones, such as amphidinols [43] and karatungiols [44] from Amphidinium spp., zooxanthellatoxins (ZTs) [45,46], and zooxanthellamides (ZADs) [47 9] from Symbiodinium spp., and durinskiols [50,51] from Durinskia spp. On the basis of their structural, biological, and conformational diversity and uniqueness, various potential abilities of such polyol compounds can be considered, that is, chemical communication with host animals, defense materials, or nutrient sources. However, the true physiological functions or roles of these compounds in the ecosystem or symbiotic relationship have rarely been clarihed. 

With the nnmber of factors affecting the delivery of the bioactive compounds, namely, the nature of the polymers constituting the system, the nature of the drug, the structural and chemical featnres of the system, among others, the development of an appropriate drug delivery system needs to be addressed in a case-by-case scenario. Below, several examples of drng delivery systems based in marine biopolymers will be assessed. 

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