Publication details

Structural and solvent effects on the 13C and 15N NMR chemical shifts of indoloquinoline alkaloids: experimental and DFT study

Authors

TOUŠEK Jaromír VAN MIERT Sabine PIETERS Luc VAN BAELEN Gitte HOSTYN Steven MAES Bert U.W. LEMIERE Guy DOMMISSE Roger MAREK Radek

Year of publication 2008
Type Article in Periodical
Magazine / Source Magnetic Resonance in Chemistry
MU Faculty or unit

Faculty of Science

Citation
Web DOI: 10.1002/mrc.2125
Doi http://dx.doi.org/10.1002/mrc.2125
Field Physical chemistry and theoretical chemistry
Keywords NMR; 1H; 13C; 15N; quantum-chemical calculations; solvent effects; indoloquinoline alkaloids; cryptolepine
Attached files
Description Indoloquinoline alkaloids represent an important class of antimalarial, antibacterial and antiviral compounds. They have been shown to bind to DNA via intercalation preferentially at GC-rich sequences containing nonalternating CC sites. The stability of complexes formed with biological macromolecules depends on noncovalent binding. In the present study, the ability of indoloquinolines to form intermolecular interactions with solvents was investigated by using NMR spectroscopy and density functional theory (DFT) (B3LYP/6-31G**) calculations. NMR data measured for indoloquinoline bases and the corresponding hydrochlorides are discussed in relation to the structure. DFT calculations of shielding constants in vacuo and in solution allowed the investigation of the influence of the environment on the NMR parameters. Calculations incorporating solvent effects indicated significant changes in the anisotropy of the electron distribution, reflected in the span of the chemical shielding tensor (Omega = delta11 - delta33). Solvent effects on the span of the 13C and 15N shielding tensor depended on the type of atom and the data indicated a significant influence of solute-solvent interactions.
Related projects:

You are running an old browser version. We recommend updating your browser to its latest version.

More info