Chemical shift assignment and conformational analysis of monoalkylated acylguanidines

Kleinmaier, Roland and Gschwind, Ruth M. (2010) Chemical shift assignment and conformational analysis of monoalkylated acylguanidines. MAGNETIC RESONANCE IN CHEMISTRY, 48 (9). pp. 678-684. ISSN 0749-1581, 1097-458X

Full text not available from this repository. (Request a copy)

Abstract

Monoalkylated acylguanidines are important functional groups in many biologically active compounds and additionally applied in coordination chemistry. Yet a straightforward assignment of the individual NH chemical shifts and the acylguanidine conformations is still missing. Therefore, in this study, NMR spectroscopic approaches for the chemical and especially the conformational assignment of protonated monoalkylated acylguanidines are presented. While NOESY and (3)J(H,H) scalar couplings cannot be applied successfully for the assignment of acylguanidines, (4)J(H,H) scalar couplings in H-1,H-1 COSY spectra allow for an unambiguous chemical shift and conformational assignment. It is shown that these (4)J(H,H) long-range couplings between individual acylguanidinium NH resonances are observed solely across all-trans (w) pathways. Already one cis orientation in the magnetisation transfer pathway leads to signal intensities below the actual detection limit and significantly lower than cross-peaks from (2)J(NH,NH) couplings or chemical exchange. However, it should be noted that also in the case of conformational exchange being fast on the NMR time scale, averaged cross-peaks from all-trans (4)J(H,H) scalar couplings are detected, which may lead at first glance to an incomplete or even wrong conformational analysis. Copyright (C) 2010 John Wiley & Sons, Ltd.

Item Type: Article
Uncontrolled Keywords: G-ACYLATED IMIDAZOLYLPROPYLGUANIDINES; NUCLEAR MAGNETIC-RESONANCE; RECEPTOR ANTAGONIST; HYDROGEN-BONDS; AMILORIDE; NMR; INHIBITORS; COUPLINGS; AGONISTS; PROTON; NMR; H-1; C-13; N-15; conformational analysis; acylguanidines; w-couplings
Subjects: 500 Science > 540 Chemistry & allied sciences
Divisions: Chemistry and Pharmacy > Institut für Organische Chemie > Arbeitskreis Prof. Dr. Ruth Gschwind
Depositing User: Dr. Gernot Deinzer
Date Deposited: 15 Jul 2020 06:44
Last Modified: 15 Jul 2020 06:44
URI: https://pred.uni-regensburg.de/id/eprint/24269

Actions (login required)

View Item View Item