Stereoselective Synthesis of (2S,3R)-α-Hydroxy-β-Amino Acids (AHBAs): Valinoctin A, (2S,3R)-3-Amino-2-Hydroxydecanoic Acid, and a Fluorescent-Labeled (2S,3R)-AHBA

Abstract

We report the stereoselective synthesis of an alkynyl side-chain containing analogues. The Cu(I)-catalyzed reactions of (R)-glyceraldehyde acetonide and dibenzylamine with terminal alkynes provided the corresponding (2S,3R) amino alcohols with good-to-excellent diastereoselectivity. Subsequent chemical transformations provided easy access to the alkynyl side-chain containing (2S,3R)-AHBAs. The utility of the methodology was demonstrated by the stereoselective synthesis of valinoctin A and (2S,3R)-3-amino-2-hydroxydecanoic acid ((2S,3R)-AHDA). Photophysical properties and cell permeability of a pyrene-labeled (2S,3R)-AHBA were also determined.