You can use Predict&Compare (or Predict&Verify) to carry out your assignments. Just open a 1D dataset with a molecular structure and follow the menu 'Analysis/Predict&Compare'. After the prediction is run, Mnova synthesizes the corresponding 1H-NMR spectrum using a rigorous full quantum mechanics method taking into account any second order effect present in the predicted spin(s) systems(s). For example, in the figure below, you can see the results of running a prediction and comparing the resulting 1H spectrum with its experimental counterpart and the applicable assignments for the predicted spectrum:
Then press the 'A' key to activate the assignment mode and select the atom and the applicable region of the experimental spectrum to be assigned (following the assignments of the predicted spectrum):
