Diazona angulata

Diazonamide derivatives, (I), prepared by Harran (1) were modeled from toxins extracted from the marine invertebrate Diazona angulata and were effective in treating disorders associated with abnormal cell mitosis. 

Diazonamide A, a marine natural product isolated from the colonial ascidian Diazona angulata. The revised structure was confirmed by total synthesis in 2002. It shows cytotoxicity against several tumor cell lines with IC50 values <15 ngmL [N. Lindquist etal.,J. Am. Chem. Soc. 1991, 113, 2303 K. C. Nicolaou et al., Angew. Chem. Int. Ed. 2002, 41, 3495]. 

The marine metabolite diazonamide A (47) (Fig. 3) was isolated from the colonial ascidian Diazona angulata, collected from the ceiUngs of caves along the northwest coast of Siquijor Island in the Phihppines [31]. The original structure of diazonamide A was suggested by an X-ray crystallographic study of the p-bromobenzoyl derivative of diazonamide B (48) (Fig. 3). Harran and coworkers completed the synthesis of the proposed diazonamide A [32], which differs from the natural diazonamide A, and thus the revised structure is 47 [33]. 

Diazonamide A Diazona angulata (ascidian) Inhibition of tubulin polymerization (169)... 

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