A new, edited HMBC experiment is introduced that leads to two subspectra according to the number of protons attached to 13C nuclei being even or odd, i.e. one subspectrum with C + CH2 and another with CH + CH3. This experiment can be useful for resolving spectral overlap among the typically large number of peaks in HMBC spectra. It is implemented in a broadband version similar to broadband HMBC and demonstrated on prednisolone [(11beta)-11,17,21-trihydroxypregna-1,4-diene-3,20-dione].
2006 John Wiley & Sons, Ltd.