(2S,4S)-1-(p-Nitrobenzyloxycarbonyl)-2-t-butyldimethylsilyloxymethyl-4-acetylthiopyrrolidine (0.85 g) was dissolved in methanol (8.5 ml), and 0.85 ml of 6N hydrochloric acid was added thereto. The resulting mixture was stirred at room temperature for 2.5 hours, diluted with ethyl acetate, washed with water, dried over anhydrous magnesium sulfate and distilled to remove the solvent. Recrystallization of the residue from diethyl ether gave (2S,4S)-1-(p-nitrobenzyloxycarbonyl)-2-hydroxymethyl-4-acetylthiopyrrolidine.
