To further highlight the utility of our method, we chose to prepare an ester of the highly polar, heteroatom rich compound (-)-negamycin (Scheme 6). (+)-Negamycin is a natural product antibiotic which has remarkable activity against both Gram-positive and Gram-negative bacteria by interfering with multiple steps of the protein synthesis pathway. While (+)-negamycin has been the target of numerous synthetic efforts, its antipode has only been synthesized once. To our knowledge, the biological activity of (-)-negamycin has not been delineated; often, the non-natural enantiomers of natural products and natural-product like compounds have divergent, surprising, and useful activity. Our synthesis commenced by deprotonation of methyl propiolate with n-BuLi and regioselective addition into commercial (S)-N-glycidylphthalimide. Lindlar reduction gave α,βunsaturated ester 64, which was converted into sulfamate 65 (CCDC 2301583) using a Johnson-Magolan sulfamoylation. Our sulfamate tethered aza-Michael cyclization converted 65 into oxathiazinane 66 (CCDC 2301584) with good yield and >20:1 diastereoselectivity. To activate oxathiazinane 66 for ring-opening, a Cbz group was appended using K2CO3 and CbzCl in CH3CN. Ring-opening proceeded smoothly by heating with KOAc in CH3CN. The methyl ester was selectively cleaved using Nicolaou's Me3SnOH protocol. Commercially available tert-butyl 2-(1-methylhydrazinyl)acetate was coupled with carboxylic acid 69 using EDC•HCl and HOBt in CH2Cl2. The acetate group was removed using K2CO3, and the phthalimide was cleaved with hydrazine hydrate.