Marine diterpene Alkaloid

ABSTRACT Marine invertebrates such as ascidians, sponges and others are a prolific source of bioactive secondary metabolites. We have isolated a variety of marine natural products from the Okinawan marine invertebrates by using the sea urchin egg assay. Our recent work, the isolation, structure determination and activities of chlorinated macrolides, sesterterpenic acids, a bromotyrosine derivative, acetogenin derived endoperoxides, diterpene alkaloids, sesquiterpene quinones and spiro-sesquiterpenes, is presented in this article. The syntheses of these metabolites are also described. 

Aral M, Yamamo Y, SetiawanA,KobayashiM. Identification of the target protein of agelasine D, a marine sponge diterpene alkaloid, as an anti-dortmant mycobacterial substance. Chembiochem 2014 15(l) 117-23. 

Debitus and coworkers [90] isolated and characterized three new diterpene alkaloids, agelasines J—K from extracts of the marine sponge Agelas cf... 

The marine isothiocyanates, with more than 80 compounds isolated so far, form the largest group of naturally occurring isothiocyanates. This well-established group of marine natural products is constituted mainly by terpene metabolites present as sesquiterpene and diterpene derivatives. The non-terpene isothiocyanate compounds include two cylindricine alkaloids and a series of long-chain aliphatic metabolites. Marine sponges constitute the main source of these compounds, although they are also found in nudibranches and tunicates. 

Terpenoids and alkaloids are the most diverse substances isolated from marine invertebrates [5,15]. Almost 98% of metabolites extracted from cni-darians are from the class Anthozoa where terpenoids dominate across the subclass Octocorallia [5,15] (Figs. 2 and 3). The order Alcyonacea (mainly the families Alcyoniidae and Xeniidae) produce half of the metabolite richness within the subclass (Fig. 1). The genus Sinularia (Alcyoniidae), for example, produces a great variety of chemical compounds ranging from sesquiterpenes to diterpenes [93]. The suborder Stolonifera (order Alcyonacea) and the orders Pennatulacea and HeUoporacea all produce isoprenoids as predominant compounds. 

The species Zopfiella latipes (strain CBS 611.97), collected on the seabed of the Indian Ocean near New Delhi, contains two antimicrobial compounds of pyrrolidinone zopfiella-mides A and B. Similar compounds have been found in several other terrestrial and marine organisms (Daferner, Anke, and Sterner, 2002). The species Penicilliumjanthinel-lum collected from sediment in the Sea of Japan, near Vladivostok (Amursky Bay), yielded shearinines A, D, E, and F, which are diterpenic indole alkaloids, several known analogs of which have been isolated from terrestrial fiingi (Smetanina et al, 2007). Shearinines A, D, and E are apoptosis inducers for human leukemia HL-60. 

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