Synonyms: 4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylicacid, 6-[2-(p-hydroxyphenyl)acetamido]-3,3-dimethyl-7-oxo- (7CI,8CI);4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid,6-[[(4-hydroxyphenyl)acetyl]amino]-3,3-dimethyl-7-oxo-, (2S,5R,6R)- (9CI);4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid,6-[[(4-hydroxyphenyl)acetyl]amino]-3,3-dimethyl-7-oxo-, [2S-(2a,5a,6b)]-; Penicillin III; Penicillin X; p-Hydroxybenzylpenicillin