Laureacetal

Laureacetal-B (70) is a tricyclic oxetane recently isolated from a marine alga. It has the interesting features of bromine substitution and a cyclic acetal structure. In view of the extreme ease of hydrolysis of 2-methoxyoxetane, it seems surprising that a strained ring cyclic acetal would be isolated from a marine source. Its structure assignment is based on spectral studies and chemical transformations (79CL301). 

Last year the unusual structure of laureacetal-A (138) was reported. A further examination of Laurencia nipponica Yamada has revealed another closely related compound, laureacetal-B (137), and it is suggested that this compound is the... 

The secochamigrane sesquiterpene laureacetal-C (215) provides a fitting introduction to the synthetic applications available to the intramolecular furan-carbonyl photocycloaddition. Initial investigations by Schreiber and Hoveyda used 3-substituted furans as substrates, and many of these were available themselves through the intermolecular photoaldol reaction (Section 2.4.5). ° For example, irradiation of... 

Figure13.11 Biogenetic hypothesis for the formation of laureacetals A and B (according to Suzuki and Kurosawa, 1979b).

Kurata, K., Suzuki, T, Suzuki, M., and Kurosawa, E. (1983a) Laureacetal-C, an unusual secoalga Laurencia nipponica Yamada. Chem. Lett., 12, 29-32. 

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