Synonyms: 4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylicacid, 6-(2-ethoxy-1-naphthamido)-3,3-dimethyl-7-oxo- (8CI);4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid,6-[[(2-ethoxy-1-naphthalenyl)carbonyl]amino]-3,3-dimethyl-7-oxo-, [2S-(2a,5a,6b)]-;6-(2-Ethoxy-1-naphthamido)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylicacid;Nafcilin 1;4-Thia-1-azabicyclo[3.2.0]heptane-2-carboxylicacid, 6-[[(2-ethoxy-1-naphthalenyl)carbonyl]amino]-3,3-dimethyl-7-oxo-,(2S,5R,6R)-;Nallpen;Naphcillin;Penicillin,(2-ethoxy-1-naphthalenyl)-;Nafcillin [INN:BAN];