(E)-3-{(2R,3S)-3-[(4R,5R)-5-(Benzyloxycarbonylamino-methyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-oxiranyl}-acrylic acid ethyl ester

3-{(2R,3S)-3-[(4R,5R)-5-(Benzyloxycarbonylamino-methyl)-2,2-dimethyl-[1,3]dioxolan-4-yl]-oxiranyl}-propionic acid ethyl ester

(1R,5S,6S,1'S)-7-benzyloxycarbonyl-6-1',2'-dihydroxyethyl-3,3-dimethyl-2,4-dioxa-7-azabicyclo<3.3.0>octane