122347-85-7
p-nitrobenzyl (2R,3R)-2-allythio-α-isopropylidene-4-oxo-3-phenoxyacetylaminoazetidine-1-acetate
→
122347-90-4
p-nitrobenzyl (2R,3R)-2-(2'-formylmethylthio)-4-oxo-3-phenoxyacetylaminoazetidine-1-oxalate