Three new alkaloids, bersavine (3), muraricine (4), and berbostrejdine (8), together with seven
known isoquinoline alkaloids (1–2, 5–7, 9, and 10) were isolated from an alkaloidal extract of the root bark
of Berberis vulgaris. The structures of the isolated
compounds were determined by spectroscopic methods, including 1D and
2D NMR techniques, HRMS, and optical rotation, and by comparison of
the obtained data with those in the literature. The NMR data of berbamine
(5), aromoline (6), and obamegine (7) were completely assigned employing 2D NMR experiments.
Alkaloids isolated in sufficient amounts were evaluated for their
in vitro acetylcholinesterase, butyrylcholinesterase (BuChE), prolyl
oligopeptidase, and glycogen synthase kinase-3β inhibitory activities.
Selected compounds were studied for their ability to permeate through
the blood–brain barrier. Significant human BuChE (hBuChE) inhibitory activity was demonstrated by 6 (IC50 = 0.82 ± 0.10 μM). The in vitro data were further
supported by computational analysis that showed the accommodation
of 6 in the active site of hBuChE.
In this detailed phytochemical study of Narcissus cv. Professor Einstein, we isolated 23 previously known Amaryllidaceae alkaloids (1–23) of several structural types and one previously undescribed alkaloid, 7-oxonorpluviine. The chemical structures were identified by various spectroscopic methods (GC-MS, LC-MS, 1D, and 2D NMR spectroscopy) and were compared with literature data. Alkaloids which had not previously been isolated and studied for cytotoxicity before and which were obtained in sufficient amounts were assayed for their cytotoxic activity on a panel of human cancer cell lines of different histotype. Above that, MRC-5 human fibroblasts were used as a control noncancerous cell line to determine the general toxicity of the tested compounds. The cytotoxicity of the tested alkaloids was evaluated using the WST-1 metabolic activity assay. The growth of all studied cancer cell lines was inhibited by pancracine (montanine-type alkaloid), with IC50 values which were in the range of 2.20 to 5.15 µM.
Fifteen Amaryllidaceae alkaloids (1-15) of various structural types were isolated by standard chromatographic methods from fresh bulbs of Narcissus poeticus cv. Pink Parasol. The chemical structures were elucidated by MS, and 1D and 2D NMR spectroscopic analyses, and by comparison with literature data. Narcipavline (5) and narcikachnine (6) are reported here for the first time. In their structure are combined two basic structural types of Amaryllidaceae alkaloids (galanthamine- and galanthindole-structural types), which represent a new structural type of these compounds. Alkaloids isolated in sufficient amounts were evaluated for their human erythrocytic acetylcholinesterase, and human serum butyrylcholinesterase (HuBuChE) inhibition activity using Ellman's method. Z-Gly-Pro-p-nitroanilide was used as substrate in the prolyl oligopeptidase (POP) assay. Untested alkaloids were also screened for their cytotoxic activity against a small panel of human cancer cells, which spanned cell lines from different tissue types. In parallel, MRC-5 human fibroblasts were employed to determine overall toxicity against noncancerous cells. Some compounds were evaluated for their antiprotozoal activity. The newly isolated alkaloid narcipavline (5) showed interesting HuBuChE inhibition activity (IC = 24.4 ± 1.2 µM), and norlycoramine (11) demonstrated promising POP inhibition (IC = 0.21 ± 0.01 mM).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.