Synthesis and biological evaluation of new oxopyrrolidine derivatives as inhibitors of acetyl cholinesterase and β amyloid protein as anti – Alzheimer’s agents

New tetracyclic systems integrated thienopyridine scaffold as an anti-dementia lead: in silico study and biological screening

Alzheimer’s disease (AD) is a multifactorial incurable neurodegenerative disorder. To date, cholinesterase inhibitors (ChEI) are the mainstay line of treatment to ameliorate the symptoms of AD. Tacrine and donepezil are considered two important cornerstones of anti-dementia drugs. Accordingly, novel series of hexahydrobenzothienocyclopentapyridines, octahydrobenzo-thienoquinolines, hexahydrocyclopenta(thienoquinoline/thienodipyridine), and octahydropyrido-thienoquinolines were efficiently synthesized from readily available reagent, e.g. cyclohexanones, cyclopentanone, and 1-methyl-piperidin-4-one to afford 14 new compounds. All new compounds were screened against their acetylcholinesterase, butyrylcholinesterase, and β-amyloid protein inhibition. In AChE inhibition assay, compound 3,7-dimethyl-1,2,3,4,7,8,9,10-octahydrobenzo[4,5]thieno[2,3-b]quinolin-11-amine (2h) showed IC50 value 9.24 ± 0.01 μM × 10−2 excelling tacrine. Compound 1,7-dimethyl-1,2,3,4,7,8,9,10-octahydrobenzo[4,5]thieno[2,3-b]quinolin-11-amine (2e) possess excellent IC50 values 0.58 ± 0.02 μM × 10−2 and 0.51 ± 0.001 μM × 10−4 for both butyrylcholinesterase and β-amyloid protein inhibition assays, sequentially. In silico ADME studies were investigated for the promising members (octahydrobenzo-thienoquinolines 2c, 2d, 2e, 2h, 2i, and octahydropyrido-thienoquinolines 4e) and all the results were illustrated. A comparative docking study was conducted between the promising members and both tacrine and donepezil in both acetyl and butyryl choline active sites. The results revealed extra binding patterns and good agreement with the biological results.

New Tetracyclic Systems Integrated Thienopyridine Scaffold As An Anti-Dementia Lead: In Silico Study And Biological Screening.. [DOI: 10.21203/rs.3.rs-1536995/v2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Alzheimer’s disease (AD) is a multifactorial incurable neurodegenerative disorder. To date, cholinesterase inhibitors (ChEI) are the mainstay line of treatment to ameliorate the symptoms of AD. Tacrine and donepezil are considered two important cornerstones as anti-dementia drugs with potent inhibitory effects. Accordingly, novel series of hexahydrobenzo-thienocyclopentapyridines, octahydrobenzo-thienoquinolines, hexahydrocyclopenta-(thienoquinoline/thienodipyridine) and octahydropyrido-thienoquinolines were efficiently synthesized from readily available reagents e.g. cyclohexanones, cyclopentanone, and 1-methylpiperidin-4-one to afford fourteen new compounds. All new compounds were screened against their acetylcholinesterase, butyrylcholinesterase and β-amyloid protein inhibition. In acetylcholinesterase inhibition assay, compound 3,7-Dimethyl-1,2,3,4,7,8,9,10-octahydrobenzo[4, 5]thieno[2,3-b]quinolin-11-amine (2h) showed IC50 value 9.24 ± 0.01 µM x10− 2 excelling tacrine itself. Compound 1,7-Dimethyl-1,2,3,4,7,8,9,10-octahydrobenzo[4, 5]thieno[2,3-b]quinolin-11-amine (2e) possessed excellent IC50 values 0.58 ± 0.02 µM x10− 2 and 0.51 ± 0.001 µM x10− 4 for both the butyrylcholinesterase and β-amyloid protein inhibition assays, sequentially. In silico ADME studies were investigated for the promising members (octahydrobenzo-thienoquinolines 2c, 2d, 2e, 2h, 2i, and octahydropyrido-thienoquinolines 4e) and all the results were illustrated. A comparative docking study was conducted between the promising members and both tacrine and donepezil in both acetyl and butyryl choline active sites. The results revealed extra binding patterns and good agreement with the biological results.

Inhibitory potential of nitrogen, oxygen and sulfur containing heterocyclic scaffolds against acetylcholinesterase and butyrylcholinesterase

Heterocycles are the key structures in organic chemistry owing to their immense applications in the biological, chemical, and pharmaceutical fields. Heterocyclic compounds perform various noteworthy functions in nature, medication, innovation etc. Most frequently, pure nitrogen heterocycles or various positional combinations of nitrogen, oxygen, and sulfur atoms in five or six-membered rings can be found. Inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes is a popular strategy for the management of numerous mental diseases. In this context, cholinesterase inhibitors are utilized to relieve the symptoms of neurological illnesses like dementia and Alzheimer's disease (AD). The present review focuses on various heterocyclic scaffolds and their role in designing and developing new potential AChE and BChE inhibitors to treat AD. Moreover, a detailed structure-activity relationship (SAR) has been established for the future discovery of novel drugs for the treatment of AD. Most of the heterocyclic motifs have been used in the design of new potent cholinesterase inhibitors. In this regard, this review is an endeavor to summarize the biological and chemical studies over the past decade (2010-2022) describing the pursuit of new N, O and S containing heterocycles which can offer a rich supply of promising AChE and BChE inhibitory activities.

Beta and Gamma Amino Acid-Substituted Benzenesulfonamides as Inhibitors of Human Carbonic Anhydrases

A series of novel benzenesulfonamide derivatives were synthesized bearing para-N β,γ-amino acid or para-N β-amino acid and thiazole moieties and their binding to the human carbonic anhydrase (CA) isozymes determined. These enzymes are involved in various illnesses, such as glaucoma, altitude sickness, epilepsy, obesity, and even cancer. There are numerous compounds that are inhibitors of CA and used as pharmaceuticals. However, most of them bind to most CA isozymes with little selectivity. The design of high affinity and selectivity towards one CA isozyme remains a significant challenge. The beta and gamma amino acid-substituted compound affinities were determined by the fluorescent thermal shift assay and isothermal titration calorimetry for all 12 catalytically active human carbonic anhydrase isozymes, showing the full affinity and selectivity profile. The structures of several compounds were determined by X-ray crystallography, and the binding mode in the active site of CA enzyme was shown.

Donepezil Derivatives Targeting Amyloid-β Cascade in Alzheimer's Disease

Alzheimer's Disease (AD) is a neurodegenerative disorder with an increasing impact on society. Because currently available therapy has only a short-term effect, a huge number of novel compounds are developed every year exploiting knowledge of the various aspects of AD pathophysiology. To better address the pathological complexity of AD, one of the most extensively pursued strategies by medicinal chemists is based on Multi-target-directed Ligands (MTDLs). Donepezil is one of the currently approved drugs for AD therapy acting as an acetylcholinesterase inhibitor. In this review, we have made an extensive literature survey focusing on donepezil-derived MTDL hybrids primarily targeting on different levels cholinesterases and amyloid beta (Aβ) peptide. The targeting includes direct interaction of the compounds with Aβ, AChE-induced Aβ aggregation, inhibition of BACE-1 enzyme, and modulation of biometal balance thus impeding Aβ assembly.

Synthesis and inhibitory activity of N-acetylpyrrolidine derivatives on α-glucosidase and α-amylase

Background and purpose:

Carbohydrate hydrolysis enzymes including α-glucosidase and α-amylase are related to type 2 diabetes mellitus. The inhibiting of these enzymes might use for type 2 diabetes mellitus treatment.

Experimental approach:

N-substituted-acetylpyrrolidine linked with -benzyl- (N-(benzyl)-2-acetylpyrrolidine (4a)) and -tosyl- (N-(tosyl)-2-acetylpyrrolidine (4b)) were synthesized and evaluated for their pharmaceutical properties against α-glucosidase and α-amylase and free radical scavenging activity. The structures of 4a and 4b were determined through spectral studies (¹H-NMR).

Findings / Results:

Both compounds 4a and 4b had highest inhibitory potential on α-glucosidase with the IC50 values of 0.52 ± 0.02 and 1.64 ± 0.08 mM, respectively. The kinetic investigation of 4a and 4b against α-glucosidase and α-amylase were functioned in mixed type inhibition. Moreover, both compounds are more likely to bind with the free enzyme than the enzyme-substrate complex based on the Ki < Ki´ on the α-glucosidase and α-amylase enzymes. Regarding the free radical scavenging, 4a had a higher capacity than 4b with IC50 values of 1.01 ± 0.010 mM for 4a and 1.82 ± 0.048 mM for 4b.

Conclusion and implications:

Our results indicated that a derivative of N-substitute-acetylpyrrolidine had high potential to inhibit α-glucosidase and α-amylase, and their free radical scavenging properties might be applied to the therapeutic care of patients with type 2 diabetes mellitus.

Design, synthesis and biological evaluation of 2,3-dihydro-5,6-dimethoxy-1H-inden-1-one and piperazinium salt hybrid derivatives as hAChE and hBuChE enzyme inhibitors

2,3-Dihydro-5,6-dimethoxy-2-[4-(4-alkyl-4-methylpiperazinium-1-yl)benzylidine]-1H-inden-1-one halide salt derivatives as a novel donepezil hybrid analogs with the property of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzyme inhibition were designed and synthesized via N-alkylation reaction of 2,3-dihydro-5,6-dimethoxy-2-[4-(4-methylpiperazin-1-yl)benzylidene]-1H-inden-1-one with some alkyl halides. Biological tests demonstrated that most of the synthesized compounds have moderate to good inhibitory activities effect on cholinesterase enzymes. Among them, 10e showed the best profile as a selected compound for inhibition of hAChE (IC50 = 0.32) and hBuChE (IC50 = 0.43 μM) enzymes. Kinetic analysis and molecular docking led to a better understanding of this compound. Kinetic studies disclosed that 10e inhibited acetylcholinesterase in mixed-type and butyrylcholinesterase in non-competitive type. The toxicity results showed that 10e is less toxic than donepezil and has better inhibitory activity against hBuChE when compared to donepezil or Galantamine. Other performed experiments revealed that 10e has an anti-β amyloid effect which is capable of reducing ROS, LDH and MDA also possing positive effect on TAC. On the other hand, it has shown a good anti-inflammation effect.

Synthesis, and molecular modeling of bis(3-(piperazine-1-yl)propyl)tungstate (BPPT) nanoparticles, and its first catalytic application for one-pot synthesis of 4H-chromene derivatives

A novel, nano-sized, bis(3-(piperazine-1-yl)propyl)tungstate (BPPT) is introduced as an efficient and reusable organometallic catalyst which is considered as a heterogeneous Bronsted-Lowry base and applied successfully for one-pot synthesis of methyl 2-amino-4-aryl substituted-4H-chromene derivatives with good to excellent yields. BPPT has been prepared via a two-step route from natrium tungstate salt. At first, the oxygens of Na₂WO₄ react with 1-bromo-3-chloropropane via nucleophilic substitution to produce bis(3-choloro propyl)tungstate. Then nucleophilic substitution of piperazine with chlorines produced bis(3-(piperazine-1-yl)propyl) tungstate. Bis(3-(piperazine-1-yl)propyl) tungstate, which was called BPPT, characterized by fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), transmission electron microscopy (TEM) and scanning electron microscope (SEM). The catalyst is heterogeneous, green and recyclable. It is a thermally stable and its handling is easy. Its catalytic activity is very high and leads to the production of 4H-pyran derivatives with good to excellent yields in short reaction times. Furthermore, molecular modeling studies and ADMETox prediction revealed that not only it can inhibit acetylcholinesterase enzyme and act as an anti-Alzheimer agent but also has no variation from Lipinski's rule of five and can be a good candidate as anti-Alzheimer agents. These above-mentioned facts can be countered as advantages of the current protocol.

Tetraclinis articulata essential oil mitigates cognitive deficits and brain oxidative stress in an Alzheimer's disease amyloidosis model

BACKGROUND

Tetraclinis articulata is used in traditional medicine and has been reported to possess antibacterial, antifungal, cytotoxic, anti-inflammatory and antioxidant properties.

PURPOSE

This study investigated the effects of T. articulata essential oil on memory and brain oxidative stress in amyloid-β peptide 1-42 (Aβ1-42)-induced an Alzheimer's disease amyloidosis model. Moreover, the underlying mechanism for memory enhancement and antioxidant activity was investigated, thus supporting its traditional use with scientific evidence for further studies.

METHODS

T. articulata essential oil was administered by inhalation to male Wistar rats once daily for 15 min period at doses of 1% and 3% for 21 days after the intracerebroventricular administration of Aβ1-42 right-unilaterally to induce memory deficits. The chemical composition of the essential oil was done by GC-MS and GC-FID. Spatial memory of rats was tested using Y-maze and radial arm maze tests. The possible underlying mechanism for memory improvement exhibited by T. articulata essential oil was investigated by in vivo brain antioxidant effect and acetylcholinesterase (AChE) inhibitory effect. In vitro, experimental evaluations were assessed through DPPH and ABTS tests.

RESULTS

The GC-MS and GC-FID data showed that the essential oil has a high percent of monoterpene hydrocarbons. Also, we demonstrated the essential oil reversed the Aβ1-42-induced decreasing of the spontaneous alternation in the Y-maze test and the Aβ1-42-induced increasing of the working and reference memory errors in the radial arm maze test. Furthermore, the Aβ1-42-decreased the acetylcholinesterase activity and the oxidant-antioxidant status in the rat hippocampus was retrieved by the treatment with the essential oil.

CONCLUSION

The study demonstrates that the essential oil could be a potent pharmacological agent against dementia by modulating cholinergic activity and promoting antioxidant action in the rat hippocampus.

Chlorinated tacrine analogs: Design, synthesis and biological evaluation of their anti-cholinesterase activity as potential treatment for Alzheimer's disease

In search of potent acetyl cholinesterase inhibitors with low hepatotoxicity for the treatment of Alzheimer's disease, introduction of a chloro substitution to tacrine and some of its analogs has proven to be beneficial in maintaining or potentiating the cholinesterase inhibitory activity. Furthermore, it was found to be able to reduce the hepatotoxicity of the synthesized compounds, which is the main target of the study. Accordingly, a series of new 4-(chlorophenyl)tetrahydroquinoline derivatives, was synthesized and characterized. The synthesized compounds were evaluated for their in vitro and in vivo anti-cholinesterase activity using tacrine as a reference standard. Furthermore, they were investigated for their hepatotoxicity compared to tacrine. The obtained biological results revealed that all synthesized compounds displayed equivalent or significantly higher anti-cholinesterase activity and lower hepatotoxicity in comparison to tacrine. In addition, in silico drug-likeness of the synthesized compounds were predicted and their practical logP were assessed indicating that all synthesized compounds can be considered as promising hits/leads. Furthermore, docking study of the compound showing the highest in vitro anticholinesterase activity was performed and its binding mode was compared to that of tacrine.