the FGHI ringsystem of yessotoxin, a marine ladder polyether, has been developed. The synthesis features convergent coupling of the diol and the aldehyde to form α-cyano ethers via acetal formation followed by ring closing metathesis and reductive etherification to construct the oxocane ring G and tetrahydropyran ring H, respectively. The β-methyl group on the G ring was stereoselectively introduced
Convergent synthesis of trans-fused 6/n/6/6 (n=7, 8) tetracyclic ether system via α-cyano ethers
作者:Tohru Oishi、Koji Watanabe、Michio Murata
DOI:10.1016/s0040-4039(03)01862-8
日期:2003.9
tetracyclic ether system via two-rings construction of the central n/6 ring system was developed. The key steps of the present synthesis involve a ring-closing metathesis reaction for the construction of the seven- and eight-membered rings, and reductive etherification for the tetrahydropyrans. Unification of the two fragments through acetal formation, followed by regioselectivecleavage of the acetal using