Coupling Constants in Proteins
Hydrogen Bond Experiments
Multiplicity edited H2BC
Heteronuclear 2-bond correlations: A two-dimensional NMR pulse sequence for long-range correlation of 1H and 13C nuclei. Multiplicity edited: CH, CH3-correlations are separated from CH2-correlations.
a) Standard sequence
b) Up-down sequence
Multiplicity edited H2BC with a 3rd order low-pass J filter for correlating 1H and 13C nuclei via 1JCH and 1H-1H couplings.
The sum and differences of two data sets from the two sequences, standard (a) and up-down (b), (prefarably acquired in an interleaved mode) are calculated to form odd and even datasets.
Filled and open bars refer to /2 and pulses, respectively, while the dashed boxes represent 13C decoupling.
The recommended phase cycle is
AnimationHave a look at a animation showing the evolution of the t1 delay.
ResultsH2BC-spectra of prednisolone in DMSO-d6 at 600 MHz. a) Normal H2BC-spectrum (standard sequence). b) Multiplicity edited H2BC-spectra (interleaved standard + up-down sequence added [blue, CH and CH3] and subtracted [red, CH2]). Expansions of NMR-spectra of prednisolone in DMSO-d6 at 600 MHz. a) Normal H2BC-spectrum (standard sequence). b) Multiplicity edited H2BC-spectra, sum of standard + up-down experiments = CH and CH3 subspectrum. c) Multiplicity edited H2BC-spectra, difference of standard + up-down experiments = CH2 subspectrum. d) HSQC. Prednisolone
PosterDownload the poster presented at the 27th Danish NMR discussion meeting 2006.
Code and procedures
Document: Edited H2BC (index.shtml)
Last modified: 2006-03-17