HMBC-type 2D HMBC 2D semi-selective HMBC ge-2D HMBC phase-sensitive HMBC long-range optimized HSQC (HSQMBC) EXSIDE J-Resolved HMBC (J-HMBC) 2D CT-HMBC

HSQC-TOCSY-type ge-2D HSQC-TOCSY alpha/beta-HSQC-TOCSY 2D HSQC-HECADE E.COSY-edited HSQC-TOCSY TROSY-edited HSQC-TOCSY 2D HETLOC

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Long-range proton-carbon coupling constants can be extracted from 2D ¹H-detected experiments, basically based in the HMBC or the HSQC-TOCSY pulse schemes ( 01MRC499): HMBC-type experiments

Rough estimation from cross-peak intensity analysis ( 91JACS10457 ) or signal amplitude analysis ( 89JMR223-83 ) of 2D HMBC, 2D semi-selective HMBC and ge-2D HMBC spectra.

Accurate values can be also extracted by careful analysis of the anti-phase multiplet patterns in phase-sensitive HMBC experiments and long-range optimized HSQC (HSQMBC) experiments

EXSIDE based on J-modulation in selective LRHSQC experiments.

J-Resolved HMBC experiments (J-HMBC).

2D CT-HMBC

HSQC-TOCSY type experiments

From pure in-phase cross-peaks in 2D HSQC-TOCSY and ge-2D HSQC-TOCSYspectra ( 97JMR125-129 , 99JMR408-137 , 00JMR294-142 ).

Modified sequences have been also reported that use the some spin-state-selective excitation principle

1H-X Correlation

In the detected F2 dimension: alpha/beta-HSQC-TOCSY experiment ( 97JB181-10 , 97JB89-10 , 99JMR237-137 , 99JMR408-137 ).

2D HSQC-HECADE experiment.

E.COSY-edited HSQC-TOCSY

TROSY-edited HSQC-TOCSY

1H-1H correlation

From E.COSY pattern of relayed peaks in 2D w₁-edited TOCSY and 2D HETLOC experiments.

This is also extended to 2D w₁-edited ROESY experiments ( 93JB81 ).

Other 2D inverse experiments

Inverse J-resolved ( 95JMRB275-109 ).