Stereocontrolled synthesis of the C-1 to C-7 fragment of erythronolide A. A model study using the 1,7-dioxaspiro[5.5]undecane system

Abstract
Propionate spiroketal was prepared by 2 different methods. This compound was then converted into the substituted spiro[5.5]undecane which contains 5 contiguous chiral centers which are found in the seco acid of erythronolide A [an antibiotic].