1184705-70-1Relevant articles and documents
Synthesis of calystegine A3 from glucose by the use of ring-closing metathesis
Monrad, Rune Nygaard,Pipper, Charlotte Bressen,Madsen, Robert
, p. 3387 - 3395 (2011/02/28)
A synthesis of the nortropane alkaloid calystegine A3 is described from D-glucose. The key step employs a zinc-mediated tandem reaction where a benzyl-protected methyl 6iodo glucoside is fragmented to give an unsaturated aldehyde, which is then transformed into the corresponding benzylimine and allylated in the same pot. The functionalized nona-l,8-diene, thus obtained, is converted into the sevenmembered carbon skeleton in calystegine A3 by ring-closing olefin metathesis. Subsequent deoxygenation by the BartonMcCombie protocol, hydroboration and oxidative workup followed by hydrogenolysis affords calystegine A3. The synthesis uses a total of 13 steps from glucose and confirms the absolute configuration of the natural product.