(4S,5S)-(-)-2,3-O-Isopropylidene-1,4-di-O-tosyl-L-threitol, (4S,5S)-(-)-2,2-Dimethyl-4,5-bis(tosyloxymethyl)-1,3-dioxide, (−)-2,3-O-Isopropylidene-1,4-di-O-tosyl-L-threitol, (-)-1,4-Di-O-tosyl-2,3-O-isopropylidene-L-threitol, (−)-2,3-O-Isopropylidene-L-threitol 1,4-ditosylate, (4S,5S)-4,5-Bis(tosyloxymethyl)-2,2-dimethyl-1,3-dioxolane, (−)-1,4-Di-O-tosyl-2,3-O-isopropylidene-L-threitol, [2,2-dimethyl-5-[(4-methylphenyl)sulfonyloxymethyl]-1,3-dioxolan-4-yl]methyl 4-methylbenzenesulfonate