(4R,5S,6S)-6-acetoxy-1-tert-butyldimethylsilyloxy-4,5,7-tribenzyloxy-2(E)-heptene

(4R,5S,6S)-1-tert-butyldimethylsilyloxy-6-[(chloro-methylsulfonyl)-oxy]-4,5,7-tribenzyloxy-2(E)-heptene

(4R,5S,6R)-1-tert-butyldimethylsilyloxy-6-[(chloromethylsulfonyl)-oxy]-4,5,7-tribenzyloxy-2(E)-heptene