Synthesis and elaboration of functionalised carbohydrate-derived spiroketals.
The scope of a stereoselective three-step approach for the synthesis of sugar derived spiroketals is presented. The methodology consists of Grignard addition of vinyl- or allylmagnesium bromide to a carbohydrate lactone, followed by K-10 clay mediated glycosidation with a terminal alkenol and subsequent ring-closing metathesis of the resulting diene. The generality of this procedure is demonstrated by the synthesis of various pyranose- and furanose-derived spiroketals, as well as more advanced tricyclic spiroketal derivatives. It is shown that functionalisation of the double bond in the resulting spiroketals leads to fused polycyclic ethers.
van Hooft
Peter A V
PA
TNO Prins Maurits Laboratory, AA Rijswijk, The Netherlands.
El Oualid
Farid
F
Overkleeft
Herman S
HS
van der Marel
Gijsbert A
GA
van Boom
Jacques H
JH
Leeuwenburgh
Michiel A
MA
D002241:Carbohydrates / Q000737:chemistry*; D007783:Lactones / Q000737:chemistry; D008968:Molecular Conformation; D013141:Spiro Compounds / Q000138:chemical synthesis*; D013237:Stereoisomerism
D002241:Carbohydrates; D007783:Lactones; D013141:Spiro Compounds