Prostaglandins cyclopentane precursor

It was during the search for a new and direct route from readily available monosaccharide derivatives to functionalized cyclopentanes which would serve as prostaglandin synthesis precursors that the reaction discussed in this chapter, and shown in outline in Scheme 1, was first encountered [1]. From the 6-de-... 

D-Glucose has been converted to the bicyclic lactone 71, in which a key 3-carbon chain homologation is effected via aldehyde allylation. This lactone is a known precursor of acdnobolin, and this synthesis thus constitutes a formal total synthesis. ° The cyclopentane-fused 5-lactone 72, a potential prostaglandin synthetic intermediate, has been prepared from levoglucosan.3t... 

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