Synonyms: VX-VC 43;6R-((R)-2-(3-(2-(p-Aminosulfonyl)anilino-4-hydroxy-5-pyrimidinyl)ureido)-2-(4-hydroxyphenyl)acetamido)penicillanic acid, sodium salt;4-Thia-1-azabicyclo(3.2.0)heptane-2-carboxylic acid, 6-((((((2-((4-(aminosulfonyl)phenyl)amino)-1,4-dihydro-4-oxo-5-pyrimidinyl)amino)carbonyl)amino)(4-hydroxyphenyl)acetyl)amino)-3,3-dimethyl-7-oxo-, monosodium salt, (2S-(2alpha,5alpha,6beta(S*)))-;sodium (2S,5R,6R)-6-({(4-hydroxyphenyl)[({6-oxo-2-[(4-sulfamoylphenyl)amino]-1,6-dihydropyrimidin-5-yl}carbamoyl)amino]acetyl}amino)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylate