Structural determination and anticholinesterase assay of C-glycosidic ellagitannins from Lawsonia inermis leaves: A study supported by DFT calculations and molecular docking.

Autor: Orabi MAA; Department of Pharmacognosy, College of Pharmacy, Najran University, Najran 55461, Saudi Arabia. Electronic address: maorabi@nu.edu.sa., Orabi EA; Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec H4B 1R6, Canada., Abdel-Sattar ES; Department of Medical Microbiology and Immunology, Faculty of Pharmacy, South Valley University, Qena 83523, Egypt., English AM; Department of Chemistry and Biochemistry, Concordia University, 7141 Sherbrooke Street West, Montréal, Québec H4B 1R6, Canada., Hatano T; Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Tsushima, Kita-Ku, Okayama 700-8530, Japan., Elimam H; Department of Biochemistry, Faculty of Pharmacy, University of Sadat City, Sadat City 32958, Egypt; Department of Biochemistry, Faculty of Pharmacy, Sinai University, Kantara, Egypt.
Jazyk: angličtina
Zdroj: Fitoterapia [Fitoterapia] 2023 Jan; Vol. 164, pp. 105360. Date of Electronic Publication: 2022 Nov 22.
DOI: 10.1016/j.fitote.2022.105360
Abstrakt: An ellagitannin monomer, lythracin M (1), and a dimer, lythracin D (2), along with eight known monomers (3-10) were isolated from Lawsonia inermis (Lythraceae) leaves. Lythracin M (1) is a C-glycosidic ellagitannin with a flavogallonyl dilactone moiety that participates in the creation of a γ-lactone ring with the anomeric carbon of the glucose core. Lythracin D (2) was determined as an atropisomer of the reported lythcarin D. These newly discovered structures (1 and 2) were determined by intensive spectroscopic experiments and by comparing DFT-calculated 1 H 1 H coupling, 1 H NMR chemical shifts, and ECD data with experimental values. The anti-acetylcholinesterase assay of the compounds 1-10 revealed that the C-1 ellagitannin epimers [casuarinin (7; IC 50  = 34 ± 2 nM) and stachyurin (8; IC 50  = 56 ± 3 nM)], and the new dimer (2; IC 50  = 61 ± 4 nM) possess enzyme inhibitory effects comparable to the reference drug (donepezil, IC 50  = 44 ± 3 nM). Molecular docking of compounds 1-10 with AChE identified the free galloyl moiety as an important pharmacophore in the anticholinesterase activity of tannins.
Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Mohamed A. A. Orabi reports financial support was provided by Najran University. Mohamed A. A. Orabi reports a relationship with Najran University that includes: employment.
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Databáze: MEDLINE