Synthetic studies on polypropionate antibiotics based on the stereospecific methylation of γ δ-epoxy acrylates by trimethylaluminum. A highly stereoselective construction of the eight contiguous chiral centers of ansa-chains of rifamycins
A highly stereoselective construction of the eight contiguous chiral centers of ansa-chains of rifamycins has been accomplished by the iterative use of the stereospecific methylation of γ,δ-epoxy acrylates by trimethylaluminum which was recently developed by us. The present work demonstrates the synthetic potential of the method for the synthesis of polypropionate antibiotics including ansamycins and