Asymmetric and diastereodivergent approach to key intermediates for the synthesis of homopumiliotoxin 223G and epiquinamide isomer

A stereoselective reaction followed by a sequential cyclization route has been used in the divergent synthesis of 1-hydroxyquinolizidione isomers. Sharpless asymmetric dihydroxylation afforded hydroxyl lactone and the following mesylation provided the required precursor for cyclization.