(3 R,4 S)- cis-3-Acetoxy-1-(4-methoxy­phenyl)-4-(2-furan­yl)­azetidin-2-one.

The enantiopure title compound, C16H15NO5, was obtained, together with its hydro­lysed (3 S,4 R)-enantiomer, by resolution of racemic cis-3-acetoxy-1-(4-methoxy­phenyl)-4-(2-furan­yl)­azetidin-2-one using a native enzyme MTCC 5125. The two H atoms on the azetidinone ring are sited in a cis configuration above the plane of the β-lactam ring, as indicated by 1H NMR. [ABSTRACT FROM AUTHOR]