NMR analysis of a pair of isomers

In this work, the structures of a pair of isomers were identified. And we showed the ability of the selective 1D version, performed the most common NMR experiments including the 1D-HMBC and GOESY experiments, to determine the isomeric composition that were found in the production process of roflumilast. The experimental results proved that this method would be even more time saving and could get more reliable results.