Searching for potential acetylcholinesterase inhibitors: a combined approach of multi-step similarity search, machine learning and molecular dynamics simulations.

Targeting acetylcholinesterase is one of the most important strategies for developing therapeutics against Alzheimer's disease. In this work, we have employed a new approach that combines machine learning models, a multi-step similarity search of the PubChem library and molecular dynamics simulations to investigate potential inhibitors for acetylcholinesterase. Our search strategy has been shown to significantly enrich the set of compounds with strong predicted binding affinity to acetylcholinesterase. Both machine learning prediction and binding free energy calculation, based on linear interaction energy, suggest that the compound CID54414454 would bind strongly to acetylcholinesterase and hence is a promising inhibitor.

Nanodisc-associated acetylcholinesterase as a novel model system of physiological relevant membrane-bound cholinesterases. Inhibition by phenolic compounds.

Acetylcholinesterase (AChE) plays a pivotal role in the cholinergic system, and its inhibition is sought after in a wide range of applications, from insect control to Alzheimer's disease treatment. While the primary physiological isoforms of AChE are membrane-bound proteins, most assays for discovering new, safer, and potent inhibitors are conducted using commercially available soluble isoforms, such as the electric eel AChE (eeAChE). In this study, we conducted a comparative analysis of the activity and selectivity to phenolic inhibitors of recombinant human AChE, eeAChE and a mutant variant of human AChE known as dAChE4. Despite numerous mutations, dAChE4 closely resembles its parental protein and serves as a suitable model for monomeric human AChE. We also established an in vitro system of membrane-bound AChE to create a model that closely mimics the physiological isoforms. This system ensures the proper work of the enzyme and allowed us to control the exact concentration of enzyme and lipids per assay.

Plant extracts as emerging modulators of neuroinflammation and immune receptors in Alzheimer's pathogenesis.

Memory loss is becoming an increasingly significant health problem, largely due to Alzheimer's disease (AD), which disrupts the brain in several ways, including causing inflammation and weakening the body's defenses. This study explores the potential of medicinal plants as a source of novel therapeutic agents for AD. First, we tested various plant extracts against acetylcholinesterase (AChE) in vitro, following molecular docking simulations with key AD-related protein targets such as MAO-B, P-gp, GSK-3ß, and CD14. Rosemary extract was found to be the most inhibitory towards AChE. The compounds found in rosemary (oleanolic acid), sage (pinocembrin), and cinnamon (italicene) showed promise in potentially binding to MAO-B. These chemicals may interact with a key protein in the brain and alter the production and removal of amyloid-ß. Luteolin (from rosemary), myricetin (from sage), chamigrene, and italicene (from cinnamon) exhibited potential for inhibiting tau aggregation. Additionally, ursolic acid found in rosemary, sage, and chamigrene from cinnamon could modulate CD14 activity. For the first time, our findings shed light on the intricate interplay between neuroinflammation, neuroprotective mechanisms, and the immune system's role in AD. Further research is needed to validate the in vivo efficacy and safety of these plant-derived compounds, as well as their interactions with key protein targets, which could lead to the development of novel AD therapeutics.

Synthesis, biological and computational evaluation of benzoxazole hybrid analogs as potential anti-Alzheimer's agents.

Aim: Current study aims exploration of bis-benzoxazole bearing bis-Schiff base scaffolds (1-16) as anti-Alzheimer's agents.Materials & methods: 2-aminophenol is used as starting materials which react with different reagents in different step to give us bis-benzoxazole bearing bis-Schiff base analogs. NMR and HREI-MS techniques were used for characterization. All derivatives demonstrated varied range of activities with IC50 values 1.10 ± 0.40-24.50 ± 0.90 µM against acetylcholinesterase (AChE) and 1.90 ± 0.70-28.60 ± 0.60 µM against butyrylcholinesterase (BuChE) in contrast to donepezil. In both cases, analog-3 was found most potent. Molecular docking explored modes of interactions between scaffolds and receptor sites of targeted enzymes.Conclusion: This study offering promising approach for optimization and development of potent inhibitors of cholinesterase enzymes.

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Imidacloprid unique and repeated treatment produces cholinergic transmission disruption and apoptotic cell death in SN56 cells.

Imidacloprid (IMI), the most widely used worldwide neonicotinoid biocide, produces cognitive disorders after repeated and single treatment. However, little was studied about the possible mechanisms that produce this effect. Cholinergic neurotransmission regulates cognitive function. Most cholinergic neuronal bodies are present in the basal forebrain (BF), regulating memory and learning process, and their dysfunction or loss produces cognition decline. BF SN56 cholinergic wild-type or acetylcholinesterase (AChE), ß-amyloid-precursor-protein (ßAPP), Tau, glycogen-synthase-kinase-3-beta (GSK3ß), beta-site-amyloid-precursor-protein-cleaving enzyme 1 (BACE1), and/or nuclear-factor-erythroid-2-related-factor-2 (NRF2) silenced cells were treated for 1 and 14 days with IMI (1 µM-800 µM) with or without recombinant heat-shock-protein-70 (rHSP70), recombinant proteasome 20S (rP20S) and with or without N-acetyl-cysteine (NAC) to determine the possible mechanisms that mediate this effect. IMI treatment for 1 and 14 days altered cholinergic transmission through AChE inhibition, and triggered cell death partially through oxidative stress generation, AChE-S overexpression, HSP70 downregulation, P20S inhibition, and Aß and Tau peptides accumulation. IMI produced oxidative stress through reactive oxygen species production and antioxidant NRF2 pathway downregulation, and induced Aß and Tau accumulation through BACE1, GSK3ß, HSP70, and P20S dysfunction. These results may assist in determining the mechanisms that produce cognitive dysfunction observed following IMI exposure and provide new therapeutic tools.

Acetylcholine regulates the melanogenesis of retinal pigment epithelia cells via a cAMP-dependent pathway: A non-neuronal function of cholinergic system in retina.

The turnover rate of melanogenesis in retinal pigment epithelium (RPE) and its molecular signaling remain unclear. This study aimed to investigate the role of cholinergic signaling in the process of melanogenesis of cultured RPE cells. Here, a human retinal pigment epithelia cell line, ARPE-19 cell, was used to study the process of melanogenesis. The mRNA and protein expressions of cholinergic molecules, e.g., acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and melanogenic molecules i.e., tyrosinase (TYR), microphthalmia-associated transcription factor (MITF), and melanin pigment were measured during melanogenesis of cultured ARPE-19 cells. Forskolin (a cAMP inducing agent), acetylcholine (ACh) and bethanechol (Bch; a muscarinic AChR agonist) were used to induce melanogenesis in the cultures. Muscarinic acetylcholine receptor (mAChR) antagonists were employed to identify the receptor subtype. During melanogenesis of ARPE-19 cells, the mRNA and protein expressions of cholinergic molecules, e.g., AChE and BChE, were increased along with melanogenic molecules, i.e., TYR, MITF and melanin pigment. Forskolin, ACh, and Bch induced an upregulation of melanogenesis in cultured ARPE-19 cultures: the induction was parallel to an increase of AChE expression. The Bch-induced enzymatic activities and mRNA levels of AChE and TYR were fully blocked by the treatments of gallamine (a M2 specific antagonist), tropicamide (a M4 specific antagonist) and atropine (non-specific antagonist for mAChRs). Cholinergic signaling via M2/M4 mAChRs regulates melanogenesis in cultured ARPE-19 cells through a cAMP-dependent pathway. This study provides insights into the regulation of RPE cell melanogenesis via a non-neuronal function of cholinergic system.

Protective effects of betanin, a novel acetylcholinesterase inhibitor, against H2O2-induced apoptosis in PC12 cells.

BACKGROUND: Dysfunction of the cholinergic system and increased oxidative stress have a crucial role in cognitive disorders including Alzheimer's disease (AD). Here, we have investigated the protective effects of betanin, a novel acetylcholinesterase (AChE) inhibitor, on hydrogen peroxide (H2O2)-induced cell death in PC12 cells. METHODS AND RESULTS: The protective effects were assessed by measuring cell viability, the amount of reactive oxygen species (ROS) production, AChE activity, cell damage, and apoptosis using resazurin, 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA), Ellman method, lactate dehydrogenase (LDH) release, propidium iodide (PI) staining and flow cytometry, and Western blot analysis. H2O2 (150 µM) resulted in cell viability reduction and apoptosis induction while, pretreatment with the betanin (10, 20, and 50 µM) and N-Acetyl-L-cysteine (NAC) (2.5 and 5 mM) significantly increased the viability (P < 0.05, P < 0.01 and P < 0.001) and at 5-50 µM betanin decreased ROS amount (P < 0.05, P < 0.01 and P < 0.001). Whereas, pretreatment with the betanin (10, 20, and 50 µM) decreased AChE activity (P < 0.001), also at 20 and 50 µM betanin reduced the release of LDH (P < 0.001), and at 10-50 µM decreased the percentage of apoptotic cells (P < 0.001). Apoptosis biomarkers such as cleaved poly (ADP-ribose) polymerase (PARP) (P < 0.01 and P < 0.001) and cytochrome c (P < 0.05 and P < 0.001) were attenuated after pretreatment of PC12 cells with betanin at 10-20 µM and 10-50 µM respectively. Indeed, survivin (P < 0.001) increased after pretreatment of cells with betanin at 10-20 µM. CONCLUSIONS: Overall, betanin may use the potential to delay or prevent cell death caused by AD through decreasing the activity of AChE as well as attenuating the expression of proteins involved in the apoptosis pathway.

Quinazolinone-Hydrazine Cyanoacetamide Hybrids as Potent Multitarget-Directed Druggable Therapeutics against Alzheimer's Disease: Design, Synthesis, and Biochemical, In Silico, and Mechanistic Analyses.

The discovery of effective multitarget-directed ligands (MTDLs) against multifactorial Alzheimer's disease (AD) remnants has been focused in an incessant drug discovery pursuit. In this perception, the current study explores the rational design, synthesis, and evaluation of 26 quinazolinone-hydrazine cyanoacetamide hybrids 7(a-j), 8(a-j), and 9(a-f) as MTDLs against AD. These new compounds were synthesized in four-step processes using simple phthalimide as the starting material without any major workup procedures and were characterized by different spectroscopic techniques. In Ellman's assay, the most potent analogues 7i, 8j, and 9d were identified as selective and mixed-type inhibitors of hAChE. Furthermore, biophysical and computational assessments revealed that the analogues 7i, 8j, and 9d were bound to both the catalytic active site and peripheral anionic site of hAChE with high affinity. The molecular dynamics simulation analysis highlighted the conformational changes of hAChE upon binding of 7i, 8j, and 9d and also the stability of resulting biomolecular systems all over 100 ns simulations. In addition to antioxidant activity, the most active congeners were found to protect substantially SK-N-SH cells from oxidative damage. Decisively, the most active analogues 7i, 8j, and 9d were assessed as potent Aß1-42 fibril modulators and protective agents against Aß1-42-induced toxicity in SH-SY5Y cells. Additionally, glioblastoma C6 cell-based assays also demonstrated the use of the most active congeners 7i, 8j, and 9d as protective agents against Aß1-42-induced toxicity. Overall, this multifunctional capacity of quinazolinone-hydrazine cyanoacetamide hybrids demonstrated the noteworthy potential of these hybrids to develop as effectual MTDLs against AD. However, further pharmacokinetics, toxicology, and behavioral studies are warranted.

Central cholinergic transmission modulates endocannabinoid-induced marble-burying behavior in mice.

Central cholinergic system and endocannabinoid, anandamide exhibits anti-compulsive-like behavior in mice. However, the role of the central cholinergic system in the anandamide-induced anti-compulsive-like behavior is still unexplored. Therefore, the present study assessed the role of central cholinergic transmission in the anandamide-induced anti-compulsive activity using a marble-burying behavior (MBB) model in mice. The modulation in the anandamide-induced effect on MBB was evaluated using mice with altered central cholinergic transmission achieved by pretreatment (i.c.v.) with various cholinergic agents like acetylcholine (ACh), acetylcholinesterase inhibitor (AChEI), neostigmine, nicotine, mAChR antagonist, atropine, and nAChR antagonist, mecamylamine. The influence of anandamide treatment on the brain AChE activity was also evaluated. The results revealed that i.c.v. injection of anandamide (10, 20 µg/mouse, i.c.v.) dose-dependently reduced MBB in mice. Moreover, anandamide in all the tested doses inhibited the brain AChE activity indicating the role of an enhanced central cholinergic transmission in its anti-compulsive-like effect . Furthermore, the anti-compulsive-like effect of anandamide (20 µg/mouse, i.c.v.) was found to be enhanced in mice centrally pre-treated with, ACh (0.1 µg/mouse, i.c.v.) or AChEI, neostigmine (0.3 µg/mouse, i.c.v.). In addition, the anandamide-induced anti-compulsive-like effect was significantly increased in mice pre-treated with a low dose of nicotine (0.1 µg/mouse, i.c.v.) while, it was attenuated by the higher dose of nicotine (2 µg/mouse, i.c.v.). On the other hand, the anandamide (20 µg/mouse, i.c.v.) induced anti-compulsive-like effect was found to be diminished in mice pre-treated with mAChR antagonist, atropine (0.1, 0.5 µg/mouse, i.c.v.) and pre-injection of nAChR antagonist, mecamylamine (0.1, 0.5 µg/mouse, i.c.v.) potentiated the anandamide induced anti-compulsive-like response in mice. Thus, the present investigation delineates the modulatory role of an enhanced central cholinergic transmission in the anandamide-induced anti-compulsive-like behavior in mice by inhibition of brain AChE or via muscarinic and nicotinic receptors mediated mechanism.

Dual-target inhibitors based on acetylcholinesterase: Novel agents for Alzheimer's disease.

Alzheimer's disease (AD) is the most common form of dementia among the elderly, accounting for 60 %-70 % of cases. At present, the pathogenesis of this condition remains unclear, but the hydrolysis of acetylcholine (ACh) is thought to play a role. Acetylcholinesterase (AChE) can break down ACh transmission from the presynaptic membrane and stop neurotransmitters' excitatory effect on the postsynaptic membrane, which plays a key role in nerve conduction. Acetylcholinesterase inhibitors (AChEIs) can delay the hydrolysis of acetylcholine (ACh), which represents a key strategy for treating AD. Due to its complex etiology, AD has proven challenging to treat. Various inhibitors and antagonists targeting key enzymes and proteins implicated in the disease's pathogenesis have been explored as potential therapeutic agents. These include Glycogen Synthase Kinase 3ß (GSK-3ß) inhibitors, ß-site APP Cleaving Enzyme (BACE-1) inhibitors, Monoamine Oxidase (MAO) inhibitors, Phosphodiesterase inhibitors (PDEs), N-methyl--aspartic Acid (NMDA) antagonists, Histamine 3 receptor antagonists (H3R), Serotonin receptor subtype 4 (5-HT4R) antagonists, Sigma1 receptor antagonists (S1R) and soluble Epoxide Hydrolase (sEH) inhibitors. The drug development strategy of multi-target-directed ligands (MTDLs) offers unique advantages in the treatment of complex diseases. On the one hand, it can synergistically enhance the therapeutic efficacy of single-target drugs. On the other hand, it can also reduce the side effects. In this review, we discuss the design strategy of dual inhibitors based on acetylcholinesterase and the structure-activity relationship of these drugs.

Synthesis of N-substituted 4-phenyl-2-aminothiazole derivatives and investigation of their inhibition properties against hCA I, II, and AChE enzymes.

In this study, thiazole derivatives containing sulphonamide, amide, and phenyl amino groups were synthesized to protect the free amino groups of 5-methyl-4-phenyl-2-aminothiazole and 4-phenyl-2-aminothiazole. Halogenated reactions of N-protected thiazole derivatives have been investigated. LCMS, FT-IR, 1H NMR, and 13C NMR spectroscopy techniques were used to elucidate the structures of the synthesized compounds. Inhibition effects of the N-protected thiazole derivatives against human carbonic anhydrase I, II (hCA I, hCA II), and acetylcholinesterase (AChE) were investigated. The best results among the synthesized N-protected thiazole derivatives showed Ki values in the range of 46.85-587.53 nM against hCA I, 35.01-578.06 nM against hCA II, and in the range of 19.58-226.18 nM against AChE. Furthermore, in silico studies with the target enzyme of the thiazole derivatives (9 and 11), which showed the best results experimentally, have examined the binding interactions of the related compounds at the enzyme active site.

AChE inhibitory activity of N-substituted natural galanthamine derivatives.

Galanthamine derivatives are known for their AChE inhibitory activity. Among them, galanthamine has been approved for treatment of Alzheimer's disease. N-Acetylnorgalanthamine (narcisine) and N-(2'-methyl)allylnorgalanthamine (the most potent natural AChE inhibitor of galanthamine type) were synthetized using N-norgalanthamine as a precursor. The NMR data described previously for narcisine were revised by two-dimensional 1H-1H and 1H-13C chemical shift correlation experiments. AChE inhibitory assays showed that N-acetylnorgalanthamine and N-formylnorgalanthamine (with previously unknown activity) are 4- and 43-times, respectively, less potent than galanthamine. In vitro (AChE inhibitory) and in silico (docking, ADME) assays and comparison of N-(2'-methyl)allylnorgalanthamine with galanthamine prove that this molecule is a very promising natural AChE inhibitor (33-times more potent than galanthamine) which further in vivo studies would provide better estimation about its applicability as a drug.

Concept of flexible no-code automation for complex sample preparation procedures.

Driven by demographic changes and dwindling Science Technology Engineering Mathematics enrolments, our research introduces no-code automation as a strategic response, aimed at mitigating labor shortages while enhancing productivity and safety in the laboratory environment. Employing a user-friendly, no-code software platform, we automated a complex HPTLC assay, enabling laboratory personnel to configure and modify workflows without requiring specialized programming skills. The manuscript outlines the deployment of a collaborative robot (cobot), a programmable logic controller (PLC), and the utilization of self-developed open-source hardware components to establish automated stations for sample handling, incubation, spraying, detection, and storage within the assay process. The research addresses challenges such as the handling of fragile HPTLC plates and the seamless integration of automated stations, solved through innovative design solutions and adaptive programming methods. This investigation demonstrates the feasibility and efficiency of no-code automation in overcoming skilled labor deficits.

Resolving Coffee Waste and Water Pollution-A Study on KOH-Activated Coffee Grounds for Organophosphorus Xenobiotics Remediation.

This study investigates using KOH-activated coffee grounds (KACGs) as an effective adsorbent for removing organophosphorus xenobiotics malathion and chlorpyrifos from water. Malathion and chlorpyrifos, widely used as pesticides, pose significant health risks due to their neurotoxic effects and environmental persistence. Spent coffee grounds, abundant biowaste from coffee production, are chemically activated with KOH to enhance their adsorptive capacity without thermal treatment. This offers a sustainable solution for biowaste management and water remediation. Adsorption kinetics indicating rapid initial adsorption with high affinity were observed, particularly for chlorpyrifos. Isotherm studies confirmed favorable adsorption conditions, with higher maximum adsorption capacities for chlorpyrifos compared to malathion (15.0 ± 0.1 mg g-1 for malathion and 22.3 ± 0.1 mg g-1 for chlorpyrifos), highlighting its potential in mitigating water pollution. Thermodynamic analysis suggested the adsorption process was spontaneous but with the opposite behavior for the investigated pesticides. Malathion interacts with KACGs via dipole-dipole and dispersion forces, while chlorpyrifos through π-π stacking with aromatic groups. The reduction in neurotoxic risks associated with pesticide exposure is also shown, indicating that no more toxic products were formed during the remediation. This research contributes to sustainable development goals by repurposing biowaste and addressing water pollution challenges through innovative adsorbent materials.

Current pharmacophore based approaches for the development of new anti-Alzheimer's agents.

Amyloid beta peptide (Aß) and hyperphosphorylated neuronal tau proteins accumulate in neurofibrillary tangles in Alzheimer's disease (AD), a chronic neurodegenerative illness. Chronic inflammation in the brain, which promotes disease progression, is another feature of the Alzheimer's disease pathogenesis. Approximately 60-70 % of dementia cases are caused by AD. The development of effective therapies for the treatment of AD is urgently needed given the severity of the condition and its rapidly rising prevalence. Cholinesterase inhibitors, beta-amyloid (A-beta), tau inhibitors, and many other medications are currently used as preventive medicine for AD. These medications can temporarily suppress dementia symptoms but cannot halt or reverse the disease's progression. Many international pharmaceutical companies have tried numerous times to develop an amyloid clearing medication based on the amyloid hypothesis, but without success. Therefore, the amyloid theory may not be entirely plausible. This review mainly covers the recent and important reported pharmacophores as the starting point to discuss already known targets like tau, butyrylcholinesterase, amyloid beta, and acetylcholinesterase and covers the literature between years 2019-2024.

Identification of isoquinoline alkaloids from Corydalis mucronifera and their acetylcholinesterase inhibitory effects.

Four new spirobenzylisoquinoline mucroniferanines N - Q (1-4) and a rare chlorinated isoquinoline mucroniferanine R (5) were isolated from Corydalis mucronifera Maxim. Their structures were elucidated based on extensive spectroscopic data analysis of HRESIMS, 1D and 2D NMR, and their absolute configurations were confirmed by ECD data. The isolated compounds were evaluated for acetylcholinesterase (AChE) inhibitory activities. Mucroniferanine R showed significant activities with IC50 values of 0.78 µM compared to galanthamine (1.34 µM). The AChE inhibitory activity was further supported by the molecular docking analysis that exhibited the accommodation of mucroniferanine R in the active site of human AChE.

Boroxazolidones: Synthesis, In Silico and In Vitro Evaluation as ACE/AChE Dual Inhibitors, and In Vivo Testing of Antihypertensive Activity.

BACKGROUND: Systemic arterial hypertension is a serious chronic health problem caused by multiple factors. It is a major risk factor for Cardiovascular Diseases (CVDs), including heart failure, coronary heart disease, and myocardial infarction. Hypertension can be effectively treated with inhibitors of the Angiotensin Converting Enzyme (ACE), such as captopril, enalapril, and lisinopril. However, these drugs are associated with significant adverse reactions (e.g., persistent coughing, skin rashes, and angioedema). OBJECTIVE: Considering the recent insights obtained by our group into the antihypertensive effect of boroxazolidones, the aim of the current contribution was to design and synthesize a series of these compounds derived from α-amino acids and evaluate them (in silico and in vitro) as inhibitors of ACE and acetylcholinesterase (AChE). METHODS: The best candidates were examined for their in vivo antihypertensive activity to regulate high blood pressure in male spontaneously hypertensive rats. Although boron-containing compounds were once thought to be toxic in any medical context, they have increasingly been used as antibiotics, antiseptics, and antineoplastic agents. BXZHis, BXZ-Lys, BXZ-Orn, BXZ-Phe, and BXZ-Pro were selected in silico as promising ACE and AChE inhibitors. After synthesis, these molecules were tested in vitro as ACE and AChE inhibitors, finding that most were effective at micromolar concentrations. The two best candidates, BXZ-Lys and BXZ-His, were evaluated in vivo with spontaneously hypertensive rats. RESULTS: BXZ-Lys significantly decreased systolic, diastolic, and mean blood pressure, being more potent than a common ACE inhibitor, captopril. CONCLUSION: Future research is required to elucidate the mechanism of action of this antihypertensive effect.

Effect of an organophosphate insecticide on the behaviour and physiology of the spider Misumenops maculissparsus (Araneae: Thomisidae).

Pests in agriculture cause significant economic damage by reducing production and product quality. While pesticides can be an alternative for pest control, their use has a significant impact on both the environment and human health. Chlorpyrifos, a widely used pesticide, affects both target and non-target organisms, including spiders. In this study, we investigated whether Misumenops maculissparsus spiders at three developmental stages (J0, J2, and adults) recognize the presence of the insecticide and how it affects their enzymatic activity. The results indicated that only J0 was able to recognize the insecticide and avoided surfaces treated with it. On the other hand, J0 and adults exhibited reduced acetylcholinesterase (AChE) activity and the activity of antioxidant enzymes was affected by the treatment. Superoxide dismutase (SOD) increased significantly in J0, catalase (CAT) in all stages, glutathione S-transferase (GST) in J2, and glutathione peroxidase (GPx) in J2 and adults. Chlorpyrifos exposure did not increase reactive oxygen species or alter cellular populations in any model.

A Series of Novel 1-H-isoindole-1,3(2H)-dione Derivatives as Acetylcholinesterase and Butyrylcholinesterase Inhibitors: In Silico, Synthesis and In Vitro Studies.

The derivatives of isoindoline-1,3-dione are interesting due to their biological activities, such as anti-inflammatory and antibacterial effects. Several series have been designed and evaluated for Alzheimer's therapy candidates. They showed promising activity. In this work, six new derivatives were first tested in in silico studies for their inhibitory ability against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. Molecular docking and molecular dynamic simulation were applied. Next, these compounds were synthesized and characterized by 1H NMR, 13C NMR, FT-IR, and ESI-MS techniques. For all imides, the inhibitory activity against AChE and BuChE was tested using Ellaman's method. IC50 values were determined. The best results were obtained for the derivative I, with a phenyl substituent at position 4 of piperazine, IC50 = 1.12 µM (AChE) and for the derivative III, with a diphenylmethyl moiety, with IC50 = 21.24 µM (BuChE). The compounds tested in this work provide a solid basis for further structural modifications, leading to the effective design of potential inhibitors of both cholinesterases.

Pharmacological evaluation and binding behavior of 4,4'-diamino-2,2'-stilbene disulfonic acid with metal ions using spectroscopic techniques.

Industrial and human activities contribute significantly to the environmental contamination of heavy metal ions (HMIs), which have detrimental effects on aquatic life, plants, and animals, causing major toxicological problems. The commercially available 4,4'-diamino-2,2'-stilbenedisulfonic acid (DSD) has been playing a vital role in the detection of heavy metal ions and has significantly inhibited a variety of cancer cells in numerous field of modern science. The current investigation aimed to ensure the detection of heavy metals ions from the environment and fluorescence imaging of DSD in the treatment of cancer cells. Fluorescence and UV-Visible spectroscopic analysis was performed to sense the selective behavior of the probe DSD with several heavy metal ions, including Fe2+, K1+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+, Mn2+, Sn2+, and Cr3+. Furthermore, DSD was subjected to examine enzyme inhibition such as anti-Alzheimer, anti-inflammatory, antioxidant, anticancer, and antimicrobial activities in search of multifaceted drugs. Test compounds have demonstrated dose-dependent responses in the in-vitro enzyme inhibition assays for acetylcholinesterase (AChE), butyrylcholinesterase (BChE), cyclooxygenase (COX), and lipoxygenase (LOX), as well as antioxidant [DPPH = 2,2-diphenyl-1-picrylhydrazyl and ABTS = 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid]. The DSD were shown to be more effective than the conventional medication galantamine in inhibiting acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), with an IC50 value of 12.18 and 20.87 µM, which is equivalent to the standard drug. The results obtained has revealed that DSD has the potential to become an effective sensor for the detection of Sn2+ ions over competing metal ions due to the inhibition of photo-induced electron transfer pathway (PET). The MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide tetrazolium) test, demonstrated that DSD had strong anticancer effects against the brain cancer cell line NIH/3T3, HeLa and MCF-7 with an IC50 value of 32.59, 15.31 and 96.46 µM respectively. The antimicrobial testing has shown that DSD outperforms the standard drug cefixime against Candida albicans and Pseudomonas aeruginosa, respectively. This study makes a substantial contribution to the ongoing search for efficient treatments for breast cancer.