3(R)-(isopropoxycarbonyl)-2(R)-methyl-β-propiolactone

(2S,3R)-2-(tert-Butyl-dimethyl-silanyloxy)-3-methyl-succinic acid dimethyl ester

(2S,3R)-2-Methyl-3-((R)-3,3,3-trifluoro-2-methoxy-2-phenyl-propionyloxy)-succinic acid dimethyl ester

(2R,3R)-2-Methyl-3-((R)-3,3,3-trifluoro-2-methoxy-2-phenyl-propionyloxy)-succinic acid dimethyl ester