Alkaloids fromLeucojum vernumand Antiretroviral Activity of Amaryllidaceae Alkaloids

Abstract

Three alkaloids, lycorine, homolycorine and 2- O-acetyllycorine, were isolated from the bulbs of Leucojum vernum (Amaryllidaceae) and identified by means of NMR analysis. The alkaloids obtained from L. vernum and from other Amaryllidaceae species were studied in vitro for HIV-1 replication inhibitory activity on MT4 cells. The cytotoxicity of the compounds in uninfected cells was evaluated by using the MTT assay and the [ (3)H]thymidine incorporation test. The antiviral activities were determined by means of the p24 antigen assay and solid-phase reverse transcriptase testing. The results demonstrate that trisphaeridine, lycorine, homolycorine, and haemanthamine possess high antiretroviral activities (IC (50) = 0.4 - 7.3 microg/mL), accompanied by low therapeutic indices (TI (50) = 1.3 - 1.9).

Revised NMR data for Incartine: an Alkaloid from Galanthus elwesii

“…Alkaloids with the lycorine type skeleton possess significant antiviral and cytotoxic activities. Compound 3 is the most studied alkaloid of this group as it possesses one of the strongest inhibitory properties such as antiviral and cytotoxic among others [6,9,10]. However, incartine showed no remarkable activity against human immunodeficiency virus (HIV) in a human cell culture system or was cytotoxic at the concentrations tested (CC 50 42.9 μM/mL).…”

Analysis of Amaryllidaceae alkaloids from Zephyranthes grandiflora by GC/MS and their cholinesterase activity

“…The chemical structures of these alkaloids are very variable as well as their pharmacological properties. Some species of this family contain galanthamine, an acetylcholinesterase inhibitor approved for the treatment of Alzheimer´s disease (AD) (Hostettman et al, 2006), as well as other alkaloids with interesting pharmacological activities: antimalarial, antiviral and antiproliferative (Campbell et al, 1988;Hohmann et al, 2002;Szlávik et al, 2004).…”

A New Amaryllidaceae Alkaloid from the Bulbs of Lycoris radiata

“…Amaryllidaceae alkaloids are produced almost by plants of galanthus genus 7 in Amaryllidaceae and are classified with three distinct scaffolds, lycorine (3)(4)(5)(6)(7)(8)(9)14), haemanthamine (1-2, 10, 15-18) and galanthamine (11)(12)(13) series, which are classified depending on the pattern of oxidative phenolic coupling. For the purpose of searching for bioactive alkaloids from natural resources, extensive phytochemical investigation of the bulbs extract of L. radiata had undertaken and finally resulted in the isolation of a new amaryllidaceae alkaloid (1), together with seventeen related alkaloids (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18). The chemical structures of isolated 1-18 ( Fig.…”

“…The chemical structures of isolated 1-18 ( Fig. 1) were established by spectroscopic analyses as 6-hydroxytazettine (1), tazettine (2), lycorine (3), 2-O-acetyllycorine (4), homolycorine (5), 9-O-demethylhomolycorine (6), hippeastrine (7), O-methyllycorenine (8), 2-α-hydroxy-6-O-methyloduline (9), haemanthidine (10), galantamine (11), dihydrogalantamine (12), lycoramine N-oxide (13), lycosinineB (14), ismine (15), trisphaeridine (16), 3-epimacronine (17), and 6-O-methylpretazettine (18), [8][9][10][11][12][13][14][15][16][17][18] respectively. In the present paper, we describe briefly the isolation and identification of a new Amaryllidaceae alkaloid (1), as well as the inhibitory activities of isolated alkaloids (1-18) on acetylcholinesterase, in vitro assay.…”

“…The other purified components (2-18) were identified by direct comparison of their spectral data with those in the literatures. [8][9][10][11][12][13][14][15][16][17][18] All isolated Amaryllidaceae alkaloids (1-18) were evaluated for the inhibitory effect on acetylcholinesterse (EC 3.1.1.7. electric eel) using acetylcholine as substrate in vitro 20 and it was observed that galantamine (11) and ismine (15) exhibited a significant inhibitory effect on the acetylcholinesterase with IC 50 values of 27.9 and 109.7 µM, when other isolated compounds showed poor inhibitions (IC 50 > 300 µM) on acetylcholinesterse, in vitro assay. …”