Implementing multiplicity editing in selective HSQMBC experiments

Measurement of long‐range heteronuclear coupling constants using the peak intensity in classical 1D HMBC spectra

“…Basically, there are two main NMR approaches for measuring long‐range 1 H– 13 C coupling constants efficiently: (a) 13 C‐edited 2D TOCSY‐based experiments and (b) long‐range 1 H– 13 C 2D correlation (HMBC/HSQMBC) experiments . Other type of experiments such as the excitation‐sculptured indirect‐detection experiment (EXSIDE), HEteronuclear Couplings from aSSCI Domain with Exclusive correlation spectroscopy (E.COSY)‐type cross‐peaks (HECADE), and ECOSY experiments have also been applied.…”

LR‐selHSQMBC: Simultaneous Detection and Quantification of Very Weak Long‐Range Heteronuclear NMR Correlations

“…The advantages of using a 1 H frequency‐selective version of the HSQMBC experiment (selHSQMBC) that has been previously reported to measure n J CH coupling constants from pure absorption IP coupling J patterns is analyzed herein . We want to explore experimental solutions in which only the intensity modulation of n J CH exclusively survives, while at the same time unwanted AP contributions due to both n J CH and J HH phase modulations are efficiently suppressed.…”

“…[9] On the other hand, HSQMBC-TOCSY [10] and ADEQUATE experiments [11][12] are alternative NMR tools to detect such longer-range correlations, although the limitations in sensitivity due to additional relaxation effects or the required 13 C-13 C selection at natural abundance are challenges to overcome.The advantages of using a 1 H frequency-selective version of the HSQMBC experiment (selHSQMBC) that has been previously reported to measure n J CH coupling constants from pure absorption IP coupling J patterns is analyzed herein. [13][14][15][16][17][18][19] We want to explore experimental solutions in which only the intensity modulation of n J CH exclusively survives, while at the same time unwanted AP contributions due to both n J CH and J HH phase modulations are efficiently suppressed. We intend to evaluate the performance of the selHSQMBC experiment for observing cross-peaks corresponding to very small n J CH coupling values, to measure them robustly, simultaneously determining their positive/negative sign.…”

Broadband1H homodecoupled NMR experiments: recent developments, methods and applications

“…A related multiplicity‐edited approach has been reported to afford additional carbon multiplicity information by simple visual inspection of the resulting positive/negative cross‐peak phases (Fig. A) . The IP pattern of the conventional selHSQMBC cross‐peaks can be converted to doublets when using HOBS homodecoupling (Fig.…”

“…Black and red cross‐peaks represent C/CH 2 and CH/CH 3 multiplicities, respectively. Reproduced with permission of reference …”