| abstract |
A process for producing β-lactam derivatives, which comprises reacting a β-lactam derivative wherein the carboxyl group is protected and which is represented by the general formula A-COO-X (wherein A represents a β-lactam derivative residue, and X represents a benzyl group having an electron-donating group in the phenyl group, a diphenylmethyl group optionally having an electron-donating group in the phenyl group, or a tert-butyl group) with a phenol to obtain a β-lactam derivative represented by the general formula: A-COOH (wherein A is the same as defined above). |