Proton-proton coupling constants are largely used as important NMR restraint in order to trace out homonuclear connectivities and also to provide important dihedral information. NMR methods to measure them:
  • Direct extraction from the 1D or nD spectrum when resolution and overlapping is not a problem.
  • From 2D J-resolved experiments
  • From 2D COSY experiments ( 01JMR276-149 )
  • From multidimensional E.COSY-type, J-quantitative and spin-state selective methods
  • Data Processing:
  • DISCO
  • J-doubling
  • J-deconvolution
  • See J(HN-HA), J(HA-HB), J(HB-HG) in proteins
  • Ring conformation in sugars
  • Sugar puckering in nucleic acids