11 aldehydes to form the &hydroxy compounds 5a-i with a diastereomeric ratio of approximately 5: l in each case (Table I). l9 The N-protected amino aldehydes 10 and 11, which were required for the preparation of 5g and 5h, respectively, were easily obtained from 3-aminopropanol (N-protection followed by oxidation) and 4-aminobutyraldehyde diethyl acetal (N-protection followed by hydrolysis).
