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(2007/10/02)(6R,7R)-8-Oxo-3-pentafluorophenyloxycarbonyloxymethyl-7-(2-thiophen-2-yl-acetylamino)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid benzhydryl ester
3-hydroxymethyl-8-oxo-7-[(2-thienylacetyl)amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid diphenylmethyl ester
(6R,7R)-3-{[Bis-(2-hydroxy-ethyl)-carbamoyloxy]-methyl}-8-oxo-7-(2-thiophen-2-yl-acetylamino)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid benzhydryl ester