2,4-diacetyl-6-methyl-2,4-diaza-bicyclo[3.2.0]heptan-3-one 、
2,4-diacetyl-6,6-dimethyl-2,4-diaza-bicyclo[3.2.0]heptan-3-one 、
2,4-diacetyl-6-tert-butyl-2,4-diaza-bicyclo[3.2.0]heptan-3-one 、
2,4-diacetyl-6,6,7,7-tetramethyl-2,4-diaza-bicyclo[3.2.0]heptan-3-one 、 2,4-diacetyl-6-methylene-2,4-diaza-bicyclo[3.2.0]heptan-3-one 、
2,4-diacetyl-6-methoxy-2,4-diaza-bicyclo[3.2.0]heptan-3-one 、 以6-acetoxy-2,4-diacetyl-2,4-diaza-bicyclo[3,2,0]heptan-3-one, melting point 151°-153° (single stereoisomer) (82% total yield)的产率得到6-acetoxy-2,4-diacetyl-2,4-diaza-bicyclo[3.2.0]heptan-3-one