Ampicillin anhydride

Bis[6α-[[(R)-amino(phenyl)acetyl]amino]penicillanic]anhydride

[2S-[2alpha[2'R*,5'S*,6'S*(S*)],5alpha,6beta(S*)]]-6-[(aminophenylacetyl)amino]-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic anhydride