Amathaspiramide alkaloids

Tyrosine-derived metabolites in this section do not include spiro-cyclohexadienyl-isoxazolines and related compounds (Sect. 3.22.3.3) or bastadins (Sect. 3.22.3.4), but they do include tyrosine-derived alkaloids that were covered in the Alkaloids section in the first survey (1). The prolific bryozoan Amathia convoluta, collected in Tasmania, has yielded amathamide G (1953) (1814), the latest of several amath-amide alkaloids from the genus Amathia (1). A Florida collection of this animal furnished the new convolutamines A-E (1954—1958) (1815), F (1959), and G (1960) (1425), and a Tasmanian sample of this bryozoan afforded convolutamine H (1961) (1319). A study of Amathia convoluta from the North Carolina coast has yielded volutamides A-E (1962-1966) (1816). Volutamides B and C reduce feeding by the pinfish (Lagodon rhomboids) and the urchin (Arbacia punctulata), respectively, and volutamides B and D are toxic toward larvae of the hydroid Eudendrium carneum. The New Zealand Amathia wilsoni contains the six novel amathaspiramides A-F (1967-1972) (1817). 

Morris BD, Prinsep MR (1999) Amathaspiramides A-F, Novel Brominated Alkaloids from the Marine Bryozoan Amathia wilsoni. J Nat Prod 62 688... 

Morris, B. D., Prinsep, M. R. Amathaspiramides A-F, novel brominated alkaloids from the marine bryozoan Amathia wilsoni. J. Nat. Prod. 1999, 62, 688-693. 

In early 2012, Arash came across the amathaspiramides (la-f), a family of marine alkaloids that were isolated in 1999 by Prinsep and coworkers from a New Zealand collection of the bryozoan Amathia wilsoni (Figure 1). The structures were determined by detailed NMR analysis, including NOESY... 

Since the isolation of the amathaspiramides in 1999, there have been efforts by various groups toward their total synthesis. In 2002, Trauner reported the first synthesis of a member of this alkaloid family, (—)-amathaspiramide F. The Sakaguchi group followed in 2008 with their own completed synthesis of (—)-amathaspiramide F. It was not until 2012 that other members of the amathaspiramide family were synthesized. The Fukuyama group completed the syntheses of the entire family (amathaspiramides A-F). ... 

Amathaspiramides A-F form an original group of alkaloids isolated from a New Zealand form of Amathia wilsoni. The cytotoxic activities of these amides are moderate, but amathaspiramide E has a strong activity against the poliomyelitis virus (Morris and Prinsep, 1999). 

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