Halomon polyhalogenation

The antitumor polyhalogenated compound halomon 290 is extracted from a red alga. Mioskowski [65] described an efficient synthesis of this intriguing compound. One of the key steps of the synthesis, a Claisen-Johnson rearrangement, afforded ester 293 allowing the introduction the stereogenic quaternary center (Scheme 6.46). 

In Figure 6.4 and in the A Word About...Halogenated Organic Compounds from the Sea, halomon, a polyhalogenated terpene produced by red algae, is shown. 

FIGURE 43.3. Violacene 64, halomon 67, and related polyhalogenated terpenes. 

Halomon is a polyhalogenated monoterpene isolated from the red alga Portieria homemannii, which has cytotoxic properties (see Chapter 13). 

Jung, M.E. and Parker, M.H. (1997) Synthesis of several naturally occurring polyhalogenated monoterpenes of the halomon class. J, Org. Chem., 62, 7094-7095. 

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