Alkaloids sponges

Sponges in the order Elaplosclerida have been the source of a family of more than 100 3-alkylpiperidine alkaloids (see Figure 9) that all appear to have been formed via a common biosynthetic pathway which is unique to marine... 

Figure 9 3-Alkylpiperidine alkaloids isolated from sponges in the order Haplosclerida...

Structures of marine sponge alkaloids manzamines and related compounds 97H(46)765. 

Manzamine alkaloids ((3-carboline derivatives from sponges), syntheses and synthetic approaches 98T6201. 

Alkylpiperidine alkaloids from marine sponges of Haploselerida order 96MI4. 

Negatively charged alkaloids are rare. The isolation of the zinc salt Clathridin (6) (Scheme 2) from the marine sponge Clathrina clathrus was reported in 1990 (90T4387). Other examples are bis(isonaamidinato) A Zinc... 

Polycyclic Diamine Alkaloids from Marine Sponges... 

Marine sponges are a source of an array of polycyclic diamine alkaloids of common biogenetic origin. This class of secondary metabolites has been the subject of four previous reviews [4-7]. Therefore, the present review will include literature reports previously not discussed, dealing with the isolation, structure determination, biological activities, and total synthesis of polycycUc diamine alkaloids isolated from marine sponges. This review will not include guanidine alkaloids [8,9] or the manzamine alkaloids [10,11], since these compounds have been recently reviewed elsewhere. Only polycycUc... 

Further members of this class of alkaloids are the araguspongines K (10) and L (11), isolated from the marine sponge Xestospongia exigua collected at Bayadha, on the Saudi Arabian Red Sea coast [16]. After evaporation of the EtOH extract, it was partitioned between hexanes and MeCN. The polar fraction was subjected to a series of chromatographic separations by column chromatography on silica gel. The structures of both alkaloids 10 and... 

Haliclonacyclamine F (25), arenosclerin D (26), and arenosclerin E (27) have been recently isolated from the sponge Pachychalina alcaloidifera endemic in Brazil [26]. The alkaloids 25-27 were isolated from the cytotoxic, antibiotic, and antituberculosis MeOH crude extract of P. alcaloidifera by a series of separations on silica-gel and cyanopropyl-bonded silica-gel columns. The structures of compounds 25-27 were established by the same approach employed for the structural elucidation of haliclonacyclamine E (13) and arenosclerins A-C (14-16) [18], as well as by comparison with NMR data for this last series of alkaloids. The alkaloids 25-27 displayed moderate cytotoxic activity against SF295 (human CNS), MDA-MB435 (human breast), HCT8 (colon), and HL60 (leukemia) cancer cell lines. 

Although several synthetic approaches have been developed toward the total synthesis of polycyclic diamine sponge alkaloids, only a few members of this class have been synthesized. 

Andersen RJ, van Soest RWM, Kong F (1996) 3-Alkylpiperidine alkaloids isolated from marine sponges in the order Haplosclerida. In Alkaloids chemical and biological perspectives. Pergamon, New York, p 301... 

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