scholarly journals Amaryllidaceae Alkaloids of Norbelladine-Type as Inspiration for Development of Highly Selective Butyrylcholinesterase Inhibitors: Synthesis, Biological Activity Evaluation, and Docking Studies

2021 ◽  
Vol 22 (15) ◽  
pp. 8308
Author(s):  
Abdullah Al Mamun ◽  
Filip Pidaný ◽  
Daniela Hulcová ◽  
Jana Maříková ◽  
Tomáš Kučera ◽  
...  

Alzheimer’s disease (AD) is a multifactorial neurodegenerative condition of the central nervous system (CNS) that is currently treated by cholinesterase inhibitors and the N-methyl-d-aspartate receptor antagonist, memantine. Emerging evidence strongly supports the relevance of targeting butyrylcholinesterase (BuChE) in the more advanced stages of AD. Within this study, we have generated a pilot series of compounds (1–20) structurally inspired from belladine-type Amaryllidaceae alkaloids, namely carltonine A and B, and evaluated their acetylcholinesterase (AChE) and BuChE inhibition properties. Some of the compounds exhibited intriguing inhibition activity for human BuChE (hBuChE), with a preference for BuChE over AChE. Seven compounds were found to possess a hBuChE inhibition profile, with IC50 values below 1 µM. The most potent one, compound 6, showed nanomolar range activity with an IC50 value of 72 nM and an excellent selectivity pattern over AChE, reaching a selectivity index of almost 1400. Compound 6 was further studied by enzyme kinetics, along with in-silico techniques, to reveal the mode of inhibition. The prediction of CNS availability estimates that all the compounds in this survey can pass through the blood-brain barrier (BBB), as disclosed by the BBB score.

Marine Drugs ◽  
2019 ◽  
Vol 17 (12) ◽  
pp. 666 ◽  
Author(s):  
Najeeb Ur Rehman ◽  
Kashif Rafiq ◽  
Ajmal Khan ◽  
Sobia Ahsan Halim ◽  
Liaqat Ali ◽  
...  

Bioassay guided isolation of the methanolic extract of marine macro brown alga Dictyopteris hoytii afforded one new metabolite (ethyl methyl 2-bromobenzene 1,4-dioate, 1), one new natural metabolite (diethyl-2-bromobenzene 1,4-dioate, 2) along with six known metabolites (3–8) reported for the first time from this source. The structure elucidation of all these compounds was achieved by extensive spectroscopic techniques including 1D (1H and 13C) and 2D (NOESY, COSY, HMBC and HSQC) NMR and mass spectrometry and comparison of the spectral data of known compounds with those reported in literature. The in vitro α-glucosidase inhibition studies confirmed compound 7 to be the most active against α-glucosidase enzyme with IC50 value of 30.5 ± 0.41 μM. Compounds 2 and 3 demonstrated good inhibition with IC50 values of 234.2 ± 4.18 and 289.4 ± 4.91 μM, respectively, while compounds 1, 5, and 6 showed moderate to low inhibition. Furthermore, the molecular docking studies of the active compounds were performed to examine their mode of inhibition in the binding site of the α-glucosidase enzyme.


Molecules ◽  
2019 ◽  
Vol 24 (6) ◽  
pp. 1174 ◽  
Author(s):  
Yilin Zhang ◽  
Yong Yan ◽  
Lufan Liang ◽  
Jie Feng ◽  
Xuejun Wang ◽  
...  

Metallo-β-lactamases (MβLs) are the target enzymes of β-lactam antibiotic resistance, and there are no effective inhibitors against MβLs available for clinic so far. In this study, thirteen halogen-substituted triazolethioacetamides were designed and synthesized as a potent skeleton of MβLs inhibitors. All the compounds displayed inhibitory activity against ImiS with an IC50 value range of 0.032–15.64 μM except 7. The chlorine substituted compounds (1, 2 and 3) inhibited NDM-1 with an IC50 value of less than 0.96 μM, and the fluorine substituted 12 and 13 inhibited VIM-2 with IC50 values of 38.9 and 2.8 μM, respectively. However, none of the triazolethioacetamides exhibited activity against L1 at inhibitor concentrations of up to 1 mM. Enzyme inhibition kinetics revealed that 9 and 13 are mixed inhibitors for ImiS with Ki values of 0.074 and 0.27μM using imipenem as the substrate. Docking studies showed that 1 and 9, which have the highest inhibitory activity against ImiS, fit the binding site of CphA as a replacement of ImiS via stable interactions between the triazole group bridging ASP120 and hydroxyl group bridging ASN233.


2021 ◽  
Vol 22 (21) ◽  
pp. 11432
Author(s):  
Syed Shams ul Hassan ◽  
Ishaq Muhammad ◽  
Syed Qamar Abbas ◽  
Mubashir Hassan ◽  
Muhammad Majid ◽  
...  

Elicitation through abiotic stress, including chemical elicitors like heavy metals, is a new technique for drug discovery. In this research, the effect of heavy metals on actinobacteria Streptomyces sp. SH-1312 for secondary metabolite production, with strong pharmacological activity, along with pharmacokinetics profile, was firstly investigated. The optimum metal stress conditions consisted of actinobacteria strain Streptomyces sp. SH-1312 with addition of mix metals (Co2+ + Zn2+) ions at 0.5 mM in Gause’s medium. Under these conditions, the stress metabolite anhydromevalonolactone (MVL) was produced, which was absent in the normal culture of strain and other metals combinations. Furthermore, the stress metabolite was also evaluated for its anti-oxidant and cytotoxic activities. The compound exhibited remarkable anti-oxidant activities, recording the IC50 value of 19.65 ± 5.7 µg/mL in DPPH, IC50 of 15.49 ± 4.8 against NO free radicals, the IC50 value of 19.65 ± 5.22 µg/mL against scavenging ability, and IC50 value of 19.38 ± 7.11 µg/mL for iron chelation capacity and the cytotoxic activities against PC3 cell lines were recorded with IC50 values of 35.81 ± 4.2 µg/mL after 24 h, 23.29 ± 3.8 µg/mL at 48 h, and 16.25 ± 6.5 µg/mL after 72 h. Further mechanistic studies have revealed that the compound MVL has shown its pharmacological efficacy by upregulation of P53 and BAX while downregulation of BCL-2 expression, indicating that MVL is following apoptosis in varying degrees. To better understand the pharmacological properties of MVL, in this work, the absorption, distribution, metabolism, excretion, and toxicity (ADMET) were also evaluated. During ADMET predictions, MVL has displayed a safer profile in case of hepatotoxicity, cytochrome inhibition and also displayed as non-cardiotoxic. The compound MVL showed good binding energy in the molecular docking studies, and the results revealed that MVL bind in the active region of the target protein of P53 and BAX. This work triumphantly announced a prodigious effect of heavy metals on actinobacteria with fringe benefits as a key tool of MVL production with a strong pharmacological and pharmacokinetic profile.


MedPharmRes ◽  
2017 ◽  
Vol 1 (1) ◽  
pp. 15-25
Author(s):  
Dao Tran ◽  
Son Tran ◽  
Vi Nguyen ◽  
Tri Le ◽  
Minh Thai ◽  
...  

In this study, a total of twenty chalcones were synthesized via Claisen-Schmidt condensation reaction and evaluated for their in vitro acetylcholinesterase inhibitory activities using Ellman’s method. Molecular docking studies on acetylcholinesterase were performed to elucidate the interactions between these chalcone derivatives and acetylcholinesterase active site at the molecular level. From the series, six compounds (S1-5 and S17) exhibited strong acetylcholinesterase inhibitory activities with IC50 values below 100 µM compared to the parent unsubstituted chalcone. Compound S17 (4’-amino-2-chlorochalcone) showed the strongest acetylcholinesterase inhibitory activity in the investigated group with IC50 value of 36.10 µM. Molecular modeling studies were consistent with the results of in vitro acetylcholinesterase inhibitory activities, and chalcone S17 could be considered as a potential lead compound for the development of new acetylcholinesterase inhibitors.


2017 ◽  
Vol 68 (11) ◽  
pp. 2560-2565
Author(s):  
Muhammad Liaqat ◽  
Tariq Mahmud ◽  
Muhammad Imran ◽  
Mazhar Iqbal ◽  
Muhammad Muddassar ◽  
...  

One pot Mannich reaction involving three components (4-fluorobenzaldehyde, aniline, cyclopentanone) was performed using ethanol as a solvent. The resulting Mannich base (FPC) was isolated and further reacted with chloride salts of Cu(II), Ni(II), Co(II), Fe(II) and Zn(II) ions to afford respective metal complexes. The structure of synthesized ligand and transition metal complexes were elucidated on the basis of IR, 1H NMR, 13C NMR, mass spectroscopy and elemental analysis. The geometries of the resulting complexes were proposed on the basis of electronic spectroscopic data and magnetic moment. The anti-enzymatic activity of the ligand and its metal complexes were carried out against urease. FPC shows potent antiurease activity with IC50 value (0.83� 0.002 �M) which is greater than standard. The Cu-complex shows excellent inhibitory action with IC50 value (16.87� 0.03 �M) while other complexes i.e Co-complex (35.59� 0.04 �M) and Ni-complex (49.93� 0.01 �M) exhibit good to moderate IC50 values as compared with control thiourea (IC50 value, 21.25� 0.15 �M). Molecular docking studies were also done on the antiurease activities of FPC and its complexes.


Proceedings ◽  
2019 ◽  
Vol 22 (1) ◽  
pp. 66 ◽  
Author(s):  
Sierra ◽  
Cortés ◽  
Tallini ◽  
Borges ◽  
Andrade ◽  
...  

The subfamily Amaryllidoideae within of the Amaryllidaceae family has an exclusive group of compounds called Amaryllidaceae alkaloids. Galanthamine, the most known Amaryllidaceae alkaloid, is approved by the FDA as an inhibitor of the enzyme acetylcholinesterase (AChE) for the palliative treatment of Alzheimer Disease (AD). However, butyrylcholinesterase (BChE) contributes critically to cholinergic dysfunction associated with AD. Thus, the development of novel therapeutics may involve the inhibition of both cholinesterase enzymes. Zephyranthes carinata, a species of the Amaryllidaceae family, has been reported to have inhibitory activity against cholinesterases. In order to determine the enzymatic inhibition potential, the major alkaloids of bulbs and leaves of Z. carinata were evaluated in both AChE and BChE. A purification and characterization process was made using different chromatographic and spectrometric techniques, and the inhibitory activity was evaluated with the Ellman method. Alkaloidal extracts of bulbs and leaves exhibited an inhibitory activity with IC50 values of 5.8 ± 0.2 and 8.7 ± 0.3 μg/mL, respectively, against AChE. Further, bulb extract showed IC50 values of 77.9 ± 3.4 μg/mL against BChE. Amaryllidaceae alkaloids hamayne, pseudolycorine, galanthine, criasbetaine, tazettine, lycoramine, hippeastidine, galanthamine, trisphaeridine, 3-epimacronine, haemanthamine, lycorine, and vittatine were purified and evaluated for their AChE and BChE inhibitory activities. Lycoramine (galanthamine type) presented the lowest IC50 value in AChE (17 ± 0.7 μg/mL), and trisphaeridine (narciclasine type) showed the lowest IC50 value in BChE (33.1 ± 3.6 μg/mL). Combined major alkaloids (>10%) were analyzed to observe synergistic behavior. The mixture alkaloids lycoramine and galanthine presented IC50 values of 14.55 ± 1.0 μg/mL against AChE, and the lycoramine, trisphaeridine, and vittatine mix presented IC50 values of 38.42 ± 3.4 μg/mL in BChE. These results showed prominent inhibitory activity against AChE and BChE enzymes, indicating their potential as agents for treating AD through a combined strategy.


Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5199
Author(s):  
Yan Fan ◽  
Zhi Huang ◽  
Xiaoshuang Wang ◽  
Yakun Ma ◽  
Yongtao Li ◽  
...  

A novel series of pyrimidine-benzotriazole derivatives have been synthesized and evaluated for their anticancer activity against human solid tumor cell lines. The most promising molecule 12O was identified for its excellent antiproliferative activities, especially against the SiHa cell line with IC50 value as 0.009 μM. Kinase inhibition assay assessed 12O was a potential multi-kinase inhibitor, which possessed potent inhibitory activities against cyclin-dependent kinases (CDKs) and fms-like tyrosine kinase (FLT) with IC50 values in the nanomolar range. Molecular docking studies illustrated that the introduction of triazole moiety in 12O was critical for CDKs inhibition. In addition, 12O inhibited cancer cell proliferation, colony-formation, and cell cycle progression and provoked apoptotic death in vitro. In an SiHa xenograft mouse model, a once-daily dose of compound 12O at 20 mg/kg significantly suppressed the tumor growth without obvious toxicity. Taken together, 12O provided valuable guide for further structural optimization for CDKs and FLT inhibitors.


1992 ◽  
Vol 67 (04) ◽  
pp. 458-460 ◽  
Author(s):  
Zhang Bin ◽  
Long Kun

SummaryGlaucocalyxin A is a new diterpenoid isolated from the ethereal extract of the leaves of Rabdosia japonica (Burm f) Hara var glaucocalyx (Maxim) Hara (Labiatae) collected in the northeastern China. When it was incubated with washed rabbit platelets, glaucocalyxin A inhibited ADP- or arachidonic acid-induced platelet aggregation with IC50 values of 4.4 μmol/1, 14.1 μmol/1 respectively. Glaucocalyxin A also inhibited PAF-induced aggregation of rabbit platelets which were refractory to ADP and arachidonic acid with an IC50 value of 13.7 μmol/1. Analysis of [3H]-PAF binding showed that glaucocalyxin A prevented [3H]-PAF binding to intact washed rabbit platelets with an IC50 value of 8.16 μmol/1, which was consistent with its inhibition of PAF-induced platelet aggregation.


2018 ◽  
Vol 17 (3) ◽  
pp. 134-139
Author(s):  
R.M. Perez-Gutierrez

Methanol extract from Lippia graveolens (Mexican oregano) was studied in order to identify inhibitory bioactives for protein tyrosine phosphatase 1B (PTP1B). Known flavone as lutein (1), and another flavone glycoside such as lutein-7-o-glucoside (2), 6-hydroxy-lutein-7-ohexoside (3) and lutein-7-o-ramnoide (4) were isolated from methanol extract of aerial parts of the Lippia graveolens. All isolates were identified based on extensive spectroscopic data analysis, including UV, IR, NMR, MS and compared with spectroscopic data previously reported. These flavones were evaluated for PTP1B inhibitory activity. Among them, compounds 1 and 3 displayed potential inhibitory activity against PTP1B with IC50 values of 7.01 ± 1.25 μg/ml and 18.4 μg/ml, respectively. In addition, compound 2 and 4 showed moderate inhibitory activity with an IC50 value of 23.8 ± 6.21 and 67.8 ± 5.80 μg/ml respectively. Among the four compounds, luteolin was found to be the most potent PTP1B inhibitor compared to the positive control ursolic acid, with an IC50 value of 8.12 ± 1.06 μg/ml. These results indicate that flavonoids constituents contained in Lippia graveolens can be considered as a natural source for the treatment of type 2 diabetes.


2020 ◽  
Vol 20 (23) ◽  
pp. 2106-2117
Author(s):  
Martin Krátký ◽  
Šárka Štěpánková ◽  
Michaela Brablíková ◽  
Katarína Svrčková ◽  
Markéta Švarcová ◽  
...  

Background: Hydrazide-hydrazones have been known as scaffold with various biological activities including inhibition of acetyl- (AChE) and butyrylcholinesterase (BuChE). Cholinesterase inhibitors are mainstays of dementias’ treatment. Objective: Twenty-five iodinated hydrazide-hydrazones and their analogues were designed as potential central AChE and BuChE inhibitors. Methods: Hydrazide-hydrazones were synthesized from 4-substituted benzohydrazides and 2-/4- hydroxy-3,5-diiodobenzaldehydes. The compounds were investigated in vitro for their potency to inhibit AChE from electric eel and BuChE from equine serum using Ellman’s method. We calculated also physicochemical and structural parameters for CNS delivery. Results: The derivatives exhibited a moderate dual inhibition with IC50 values ranging from 15.1-140.5 and 35.5 to 170.5 μmol.L-1 for AChE and BuChE, respectively. Generally, the compounds produced a balanced or more potent inhibition of AChE. N'-[(E)-(4-Hydroxy-3,5-diiodophenyl)methylidene]-4- nitrobenzohydrazide 2k and 4-fluoro-N'-(2-hydroxy-3,5-diiodobenzyl)benzohydrazide 3a were the most potent inhibitors of AChE and BuChE, respectively. Structure-activity relationships were established, and molecular docking studies confirmed interaction with enzymes. Conclusion: Many novel hydrazide-hydrazones showed lower IC50 values than rivastigmine against AChE and some of them were comparable for BuChE to this drug used for the treatment of dementia. They interact with cholinesterases via non-covalent binding into the active site. Based on the BOILEDEgg approach, the majority of the derivatives met the criteria for blood-brain-barrier permeability.


Sign in / Sign up

Export Citation Format

Share Document