Flomoxef Impurity 24

(6R,7R) -3- (((1- (2- ((2R) -2- ((2R) -4-carboxy-5- ((4- (2-hydroxyethyl) -5-thioxo-4,5-dihydro-1H-tetrazol-1-yl) methyl) -5,6-dihydro-2H-1,3-oxazin-2-yl) -2- (2- ((difluoromethyl) thio) acetamido) -2-methoxyacetoxy) ethyl) -1H-tetrazol-5-yl) thio) methyl) -7- (2- ((difluoromethyl) thio) acetamido) -7-methoxy-8-oxo-5-oxa-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid