The incidence rate of malaria and the ensuing mortality prompts the development of novel antimalarial drugs. In this work, the activity of twenty-eight Amaryllidaceae alkaloids (1-28) belonging to seven different structural types was assessed, as well as twenty semisynthetic derivatives of the β-crinane alkaloid ambelline (28a-28t) and eleven derivatives of the α-crinane alkaloid haemanthamine (29a-29k) against the hepatic stage of Plasmodium infection. Six of these derivatives (28h, 28m, 28n and 28r-28t) were newly synthesized and structurally identified. The most active compounds, 11-O-(3,5-dimethoxybenzoyl)ambelline (28m) and 11-O-(3,4,5-trimethoxybenzoyl)ambelline (28n), displayed IC50 values in the nanomolar range of 48 and 47 nM, respectively. Strikingly, the derivatives of haemanthamine (29) with analogous substituents did not display any significant activity, even though their structures are quite similar. Interestingly, all active derivatives were strictly selective against the hepatic stage of infection, as they did not demonstrate any activity against the blood stage of Plasmodium infection. As the hepatic stage is a bottleneck of the plasmodial infection, liver-selective compounds can be considered crucial for further development of the malaria prophylactics.

• Keywords
• Amaryllidaceae, Plasmodium, alkaloids, ambelline, cytotoxicity, haemanthamine, hepatic stage, malaria,
• Publication type
• Journal Article MeSH

The search for novel antimycobacterial drugs is a matter of urgency, since tuberculosis is still one of the top ten causes of death from a single infectious agent, killing more than 1.4 million people worldwide each year. Nine Amaryllidaceae alkaloids (AAs) of various structural types have been screened for their antimycobacterial activity. Unfortunately, all were considered inactive, and thus a pilot series of aromatic esters of galanthamine, 3-O-methylpancracine, vittatine and maritidine were synthesized to increase biological activity. The semisynthetic derivatives of AAs were screened for their in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Ra and two other mycobacterial strains (M. aurum, M. smegmatis) using a modified Microplate Alamar Blue Assay. The most active compounds were also studied for their in vitro hepatotoxicity on the hepatocellular carcinoma cell line HepG2. In general, the derivatization of the original AAs was associated with a significant increase in antimycobacterial activity. Several pilot derivatives were identified as compounds with micromolar MICs against M. tuberculosis H37Ra. Two derivatives of galanthamine, 1i and 1r, were selected for further structure optimalization to increase the selectivity index.

• Keywords
• 3-O-methylpancracine, Amaryllidaceae, analogues, antimycobacterial activity, cytotoxicity, galanthamine, tuberculosis,
• MeSH
• Amaryllidaceae Alkaloids adverse effects   chemical synthesis   pharmacology   MeSH
• Anti-Bacterial Agents adverse effects   chemical synthesis   pharmacology   MeSH
• Hep G2 Cells MeSH
• Humans MeSH
• Microbial Sensitivity Tests MeSH
• Mycobacterium tuberculosis drug effects   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Amaryllidaceae Alkaloids MeSH
• Anti-Bacterial Agents MeSH

Alzheimer's disease (AD) is a progressive age-related neurodegenerative disease recognized as the most common form of dementia among elderly people. Due to the fact that the exact pathogenesis of AD still remains to be fully elucidated, the treatment is only symptomatic and available drugs are not able to modify AD progression. Considering the increase in life expectancy worldwide, AD rates are predicted to increase enormously, and thus the search for new AD drugs is urgently needed. Due to their complex nitrogen-containing structures, alkaloids are considered to be promising candidates for use in the treatment of AD. Since the introduction of galanthamine as an antidementia drug in 2001, Amaryllidaceae alkaloids (AAs) and further isoquinoline alkaloids (IAs) have been one of the most studied groups of alkaloids. In the last few years, several compounds of new structure types have been isolated and evaluated for their biological activity connected with AD. The present review aims to comprehensively summarize recent progress on AAs and IAs since 2010 up to June 2021 as potential drugs for the treatment of AD.

• Keywords
• Alzheimer’s disease, acetylcholinesterase, butyrylcholinesterase, docking study, isoquinoline alkaloids, monoaminooxidase, neuroprotective activity, prolyl oligopeptidase,
• MeSH
• Amaryllidaceae Alkaloids metabolism   MeSH
• Alzheimer Disease metabolism   MeSH
• Amaryllidaceae chemistry   MeSH
• Neurodegenerative Diseases metabolism   MeSH
• Prolyl Oligopeptidases metabolism   MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Amaryllidaceae Alkaloids MeSH
• Prolyl Oligopeptidases MeSH

Thirteen known (1-12 and 16) and three previously undescribed Amaryllidaceae alkaloids of belladine structural type, named carltonine A-C (13-15), were isolated from bulbs of Narcissus pseudonarcissus cv. Carlton (Amaryllidaceae) by standard chromatographic methods. Compounds isolated in sufficient amounts, and not tested previously, were evaluated for their in vitro acetylcholinesterase (AChE; E.C. 3.1.1.7), butyrylcholinesterase (BuChE; E.C. 3.1.1.8) and prolyl oligopeptidase (POP; E.C. 3.4.21.26) inhibition activities. Significant human BuChE (hBUChE) inhibitory activity was demonstrated by newly described alkaloids carltonine A (13) and carltonine B (14) with IC50 values of 913 ± 20 nM and 31 ± 1 nM, respectively. Both compounds displayed a selective inhibition pattern for hBuChE with an outstanding selectivity profile over AChE inhibition, higher than 100. The in vitro data were further supported by in silico studies of the active alkaloids 13 and 14 in the active site of hBuChE.

• Keywords
• Alzheimer’s disease, Amaryllidaceae, Narcissus pseudonarcissus cv. Carlton, alkaloids, butyrylcholinesterase, carltonine A–C, docking studies,
• MeSH
• Alkaloids chemistry   pharmacology   MeSH
• Butyrylcholinesterase chemistry   metabolism   MeSH
• Cholinesterase Inhibitors chemistry   pharmacology   MeSH
• Humans MeSH
• Narcissus chemistry   MeSH
• Molecular Docking Simulation MeSH
• Protein Binding MeSH
• Binding Sites MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Alkaloids MeSH
• Butyrylcholinesterase MeSH
• Cholinesterase Inhibitors MeSH

Plants of the Amaryllidaceae family are promising therapeutic tools for human diseases and have been used as alternative medicines. The specific secondary metabolites of this plant family, called Amaryllidaceae alkaloids (AA), have attracted considerable attention due to their interesting pharmacological activities. One of them, galantamine, is already used in the therapy of Alzheimer's disease as a long acting, selective, reversible inhibitor of acetylcholinesterase. One group of AA is the montanine-type, such as montanine, pancracine and others, which share a 5,11-methanomorphanthridine core. So far, only 14 montanine-type alkaloids have been isolated. Compared with other structural-types of AA, montanine-type alkaloids are predominantly present in plants in low concentrations, but some of them display promising biological properties, especially in vitro cytotoxic activity against different cancerous cell lines. The present review aims to summarize comprehensively the research that has been published on the Amaryllidaceae alkaloids of montanine-type.

• Keywords
• Amaryllidaceae, alkaloids, biological activity, derivatives, montanine, montanine-type, pancracine,
• MeSH
• Amaryllidaceae Alkaloids chemistry   isolation & purification   pharmacology   MeSH
• Amaryllidaceae chemistry   metabolism   MeSH
• Antiprotozoal Agents chemistry   isolation & purification   pharmacology   MeSH
• Cholinesterase Inhibitors chemistry   isolation & purification   pharmacology   MeSH
• Phenanthridines chemistry   isolation & purification   pharmacology   MeSH
• Antineoplastic Agents, Phytogenic chemistry   isolation & purification   pharmacology   MeSH
• Galantamine chemistry   isolation & purification   pharmacology   MeSH
• Heterocyclic Compounds, 4 or More Rings chemistry   isolation & purification   pharmacology   MeSH
• Inhibitory Concentration 50 MeSH
• Isoquinolines chemistry   isolation & purification   pharmacology   MeSH
• Humans MeSH
• Cell Line, Tumor MeSH
• Nootropic Agents chemistry   isolation & purification   pharmacology   MeSH
• Plant Extracts chemistry   MeSH
• Secondary Metabolism MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Amaryllidaceae Alkaloids MeSH
• Antiprotozoal Agents MeSH
• Cholinesterase Inhibitors MeSH
• Phenanthridines MeSH
• Antineoplastic Agents, Phytogenic MeSH
• Galantamine MeSH
• hemanthamine MeSH Browser
• Heterocyclic Compounds, 4 or More Rings MeSH
• Isoquinolines MeSH
• montanine MeSH Browser
• Nootropic Agents MeSH
• pancracine MeSH Browser
• Plant Extracts MeSH