Efficient Asymmetric Synthesis of (2R,3R)-3-{(1R)-1-[tert-Butyl(dimethyl)-siloxy]ethyl}-4-oxoazetidin-2-yl Acetate

Synthesis of 2-Keto-d- and l-gluconic Acid via Stereoselective Direct Aldol Reactions

Stereoselective direct aldol reaction between optically pure d- or l-glyceraldehyde and hydroxyacetylfuran is demonstrated as an efficient and straightforward methodology for the synthesis of six-carbon atom d- and l-arabino-hex-2-ulosonic acids. syn-Selective aldol reactions realized by using either tertiary amines or a dizinc aldol catalyst constitute two parallel routes to the de novo synthesis of orthogonally protected biologically relevant 2-keto-d- and l-gluconic acids.