An efficient and highly stereocontrolled synthesis of (2R, 3R, 4R, 6R)-3-hydroxy-2, 4, 6- trimethyloctanoic acid, the β-hydroxy acid unit that acylates the N-terminus of homophymine A, has been devised starting from iodoethane and (S, S)-pseudoephedrine propionamide in 9 steps and 36% average overall yield. Comparison of the 1H and 13C NMR and optical rotation data of the resulting β-hydroxy acid with the natural fragment unambiguously ...