Assignment of the 13C resonances of the highly delta opioid receptor selective cyclic peptide (Formula Presented.) enkephalin (DPDPE) was accomplished by using single‐quantum inverse proton detected 2D heteronuclear correlation spectroscopy. The pulse sequences described provided better sensitivity and resolution than the corresponding, commonly used, multiple‐quantum evolution experiments, since during the SQ‐evolution period there is no line broadening due to scalar and dipolar 1H‐1H interactions. The proton detected C,H correlation spectrum, in combination with the H‐TOCSY relay C,H correlation, gave the assignment of all protonated carbons. The C,H correlation optimized for long‐range coupling gave the assignments of all non‐protonated carbons, such as the carbonyl carbons of the peptide bonds. These spectra also allowed the sequential assignment of this molecule.
- Delta opioid receptor agonist peptide
- Inverse experiments
- Long‐range H,C correlations
ASJC Scopus subject areas
- Materials Science(all)