Cystodytes

Two new polycyclic pyridoacridine alkaloids, arnoamine B, 289, and its demethylated analogue, arnoamine A, have been isolated from the ascidian Cystodytes sp. These new compounds are the first known examples of pyrroles fused to pyridoacridines, have antifungal properties, and are cytotoxic in several human tumor cell lines <1998JOC1657>. Both these compounds have been synthesized, starting from the hydrazone 290 with a Fischer indole synthesis (Scheme 73) <2000JOC5476>. 

Dehydrokuanoniamine B (127) and shermilamine C (128) were isolated from a Cystodytes sp. from Fiji. Their structures were determined by analysis of spectroscopic data. These compounds displayed dose-dependent inhibition of proliferation in human colon tumour cells in vitro [142]. Shermilamines D (129) and E (130) were... 

As representative of the derivatives of pyridoacridine, eilatin, a marine alkaloid inhibits in vitro cell proliferation in chronic myeloid leukemia patients [244], Other members of the pyridoacridines, such as alkaloids isolated from a Cystodytes sp. ascidian, inhibit topoisomerase II [245], Additionally, analogues derivatives of these type of alkaloids showed interesting anti-HIV activity [246],... 

Kobayashi, J., Cheng, J. F., Walchli, M. R., Nakamura, H., Hirata, Y., Saski, T., and Ohizumi, Y., Cysodytins A, B, and C, novel tetracyclic aromatic alkaloids with potent antineoplastic activity from the Okinawan tunicate Cystodytes dellechiajei, J. Nat. Prod., 53, 1800, 1988. 

Ascididemin] Cystodytes dellechiajei (ascidian) DNA intercalator (TOPII)... 

The tunicate Cystodytes dellechiajei is a very rich source of pyrido[2,3,-... 

Tunicates are the only marine invertebrates in which alkaloid biosynthesis has been extensively investigated (189). In addition to the eudistomins, described below, the tripeptide tunichromes have been investigated, by Nakanishi and coworkers at Columbia University, in the solitary tunicate Ascidia nigra (191) and shermilamine, a benzo-3,6-phenanthroline alkaloid, has been studied in Cystodytes dellechiajei, by Steffan and coworkers at the University of Munich (192). The origin of the (3-carboline ring system of the eudistomins has been studied, by Baker s group at Florida Tech, in Eudistoma olivaceum (193, 194). 

The presence of the same or closely related compounds in multiple phyla in instances in which a predator/prey relationship cannot be established for the organisms. The isolation of p3oidinoacndine alkaloids, such as dercitamide (Scheme 24), from both the sponge Dercitus sp. and the ascidian Cystodytes (47) is an example of this. 

The ascidian fauna of southern Africa are poorly known and the 145 species presently described are thought to represent only a small fraction of the overall ascidian biodiversity [3]. Not unexpectedly, common Pacific and Atlantic fouling species e.g. Cystodytes delechiajei, Clavellina lepadiformis, Didemnum listerianum and Ciona intestinalis frequent harbours in the southern African region [3]. 

The tunicate Cystodytes dellechiajei is a very rich source of pyrido[2,3,-4-k/]acridine alkaloids. Nine tetracyclic alkaloids, cystodytins A-1128-136, have been isolated from this species (88JOC1800 91JNP1634). Except for cystodytin C 130, all other cystodytins were isolated as inseparable isomeric pairs (3.5 1) of cystodytins, )3,)3-dimethylacrylate and tiglate amides... 

Shermilamines A and B were isolated from a purple Trididemnum sp. [146,147], while shermilamine C was reported from a purple fleshy Cystodytes sp. from Fiji [132]. Both shermilamines A and B were reported in a paper which described metabolites from Amphicarpa meridiana and Leptoclinides sp. [145], while shermilamine B was also reported under the name debromoshermilamine from a Red Sea Eudistoma sp, [135]. Biosynthetic studies on shermilamine B have been reported [150]. The... 

In 1994, Francisco et al. isolated ascididemin as a major alkaloid from the grey morphs of the ascidian Cystodytes delle chiajei (Polycitor idae) collected near Punta de la Crev in the Balearic Isles, Spain 150). The CHCls/MeOH extract of the ascidian was first solvent partitioned and then subjected to chromatographic purification, which afforded ascididemin (323) (0.43% dry weight). 

Cystodamine (378) was isolated from the ascidian Cystodytes delle chiajei collected near the Bay of Gabes (at 7 m depth), Skhira, Tunisia, in 1992. 

In 1994, Ireland et al. reported the isolation and structure elucidation of a new cystodytin called cystodytin J (388) from a Fijian Cystodytes sp. ascidian (171). 

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