1H-13C HSQC spectra are designed to show correlations between carbons and their directly attached protons. Interpretation of all the correlations observed in a HSQC spectrum is an essential step in characterizing a new molecule. It is not uncommon, however, to observe HSQC correlations over more than one bond. At first these long range correlations can be quite confusing, but if one is aware of the possibility of long range correlations being present, they can actually help the analysis.
