SYNTHESIS OF REACTIVE INTERMEDIATES FOR NATURAL CYCLOPENTANE DERIVATIVES FROM (-)-QUINIC ACID: PREPARATION OF 11α-HYDROXY-13-OXAPROSTANOIC ACID

We describe a flexible, stereocontrolled synthesis of enantiomerically pure substituted cyclopentenes and cyclopentanes - including 11α-hydroxy-13-oxaprostanoic acid 20 - (−)-quinic acid via an acyclic precursor 6 by an intramolecular aldolisation-dehydration reaction.