Stereoselective Preparationof C1-C10 and C11-O14 Fragments of Narbonolide:Exploiting the Versatility of Thiazolidinethione Chiral Auxiliary

An efficient stereoselective synthesis of the C1-C10 and C 11-O14 fragments ofnarbonolide, have been accomplished by using a thiazolidinonethione as chiral auxiliary. The stereocenters at C2, C3, C4, C5, C8, and C9 in C1-C10 fragment and C12 and C13 in Cl 1-C14 fragment were generated via asymmetric acyl-thiazolidinethione aldol reactions whereas the stereocenter at C6 was installed by means of Myers alkylation.