| 摘要 |
The objective of the present invention is to provide a method for simply and efficiently producing an optically active bicyclic urea compound that is useful as an intermediate for a &bgr;-lactamase inhibitor. According to the present invention, a given ester compound and an amine are reacted with each other in the presence of a metal alkoxide and/or an alkaline earth metal salt, thereby producing a corresponding amide compound. After that, the amide compound is reacted with phosgene or a phosgene equivalent and, if necessary, treated with an acid or a base, thereby producing an optically active bicyclic urea compound. Consequently, an optically active bicyclic urea compound can be simply and efficiently produced with high optical purity without using expensive catalyst, condensation agent and the like, and without requiring protection and deprotection steps. |
