D. kyselina (2S,5R,6R-6-{(2R)-2-[[[(2S,5R,6R)-6-[(2R)-2-[[(4-ethyl-23-dioxopiperazin-1-yl)karbonyl]amino]-2-fenylacetamido]-3,3-dimethyl-7-oxo-4-thia-1-azabicyklo[3,2,0]hept-2-yl]karbonyl]amino]-2-fenylacetamido}-3,3-dimethyl-7-oxo-4-thia-1-azabicyklo[3,2,0]heptan-2-karboxylová (piperacilinylampicilin),