Biosynthesis polyether toxins

The formation of the six-membered ether ring via epoxy ester-ortho ester cyclic ether rearrangement supports the hypothesis that epoxy ester-ortho ester cyclic ether rearrangement may be involved in the biosynthesis of ladder-type marine polyether toxins. This reaction represents a biomimetic preparation of medium ring cyclic ethers. 

Satake, M., Biosynthesis of marine polyether toxin, yessotoxin, Tennen Yuki Kagobutsu Toronkai Koen Yoshishu, 42, 259, 2000. 

Polyepoxide Cyclization Cascade Based on the proposed biosynthesis of polyether toxins, Holton and coworkers used an electrophile-initiated epoxy alcohol cyclization cascade as a key step for the total synthesis of hemibrevetoxin B (37) (Scheme 4.7) [14], Treatment of 33 with N-phenylselenophthalimide (A -PSP) led to sequential cyclization to give 36 in 83% yield as a single stereoisomer. The cascade... 

Norte, M., Padilla, A., and Fernandez, J.J. (1994) Studies on the biosynthesis of the polyether marine toxin dinophysistoxin-1 (DTX-1). Tetrahedron Lett., 35,1441-1444. 

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