(2S,3R,4S)-5-(tert-Butyl-diphenyl-silanyloxy)-3-ethyl-2-hydroxy-4-(toluene-4-sulfonylamino)-pentanoic acid

(-)-(4S,5S)-5-{[(tert-butyldiphenylsilyl)oxy]methyl}-1-tosyl-4-[4-(trimethylsilyl)but-3-ynyl]pyrrolidin-2-one

(-)-(2S,3S)-5-{[(tert-butyldiphenylsilyl)oxy]methyl}-4-but-3-ynyl-1-tosyl-2,3-dihydro-1H-pyrrole

(2SR,4S,5S)-5-{[(tert-butyldiphenylsilyl)oxy]methyl}-4-but-3-ynyl-1-tosylpyrrolidin-2-ol

(2SR,4S,5S)-5-{[(tert-butyldiphenylsilyl)oxy]methyl}-1-tosyl-4-[4-(trimethylsilyl)but-3-ynyl]pyrrolidin-2-ol