The green synthesis and molecular docking of novel N-substituted rhodanines as effective inhibitors for carbonic anhydrase and acetylcholinesterase enzymes

Innovative approaches in acetylcholinesterase inhibition: a pathway to effective Alzheimer's disease treatment

Acetylcholinesterase inhibitors (AChEIs) are essential in the treatment of neurodegenerative disorders like Alzheimer's disease, as they prevent the breakdown of acetylcholine, thereby enhancing cognitive function. This review provides a comprehensive analysis of the structural motifs and mechanisms governing AChEI pharmacological activity, with a focus on medicinal chemistry strategies to enhance potency, selectivity, and pharmacokinetic properties. Beginning with the physiological role of acetylcholinesterase in neurological disorders, the review explores the historical evolution of AChEIs and highlights key structural interactions with catalytic, peripheral anionic, and allosteric binding sites. Advances in computational modeling, virtual screening, and structure-based drug design are discussed, alongside emerging approaches, such as multi-target-directed ligands and prodrugs. Additionally, the significance of natural products and drug repurposing in identifying novel AChEI scaffolds is emphasized, contributing to chemical diversity and innovation in drug discovery. By integrating computational tools, expansive chemical libraries, and innovative design strategies, this review identifies promising directions for developing effective AChEIs. These advancements hold great potential in addressing the multifaceted nature of neurodegenerative diseases and improving therapeutic interventions.

Predicting Carbonic Anhydrase Binding Affinity: Insights from QM Cluster Models

A systematic series of QM cluster models has been developed to predict the trend in the carbonic anhydrase binding affinity of a structurally diverse dataset of ligands. Reference DLPNO-CCSD(T)/CBS binding energies were generated for a cluster model and used to evaluate the performance of contemporary density functional theory methods, including Grimme's "3c" DFT composite methods (r2SCAN-3c and ωB97X-3c). It is demonstrated that when validated QM methods are used, the predictive power of the cluster models improves systematically with the size of the cluster models. This provided valuable insights into the key interactions that need to be modeled quantum mechanically and could inform how the QM region should be defined in hybrid quantum mechanics/molecular mechanics (QM/MM) models. The use of r2SCAN-3c on the largest cluster model composed of 16 residues appears to be an economical approach to predicting binding trends compared with using more robust DFT methods such as ωB97M-V and provides a significant improvement compared with docking.

Exploring heterocyclic scaffolds in carbonic anhydrase inhibition: a decade of structural and therapeutic insights

Heterocyclic compounds represent a prominent class of molecules with diverse pharmacological activities. Among their therapeutic applications, they have gained significant attention as carbonic anhydrase (CA) inhibitors, owing to their potential in the treatment of various diseases such as epilepsy, cancer and glaucoma. CA is a widely distributed zinc metalloenzyme that facilitates the reversible interconversion of carbon dioxide and bicarbonate. This reaction is essential for numerous physiological and pathological processes. In humans, CA exists in sixteen different isoforms, labeled hCA-I to hCA-XV, each distributed across various tissues and organs and involved in crucial physiological functions. Clinically utilized CA inhibitors, such as brinzolamide, dorzolamide and acetazolamide, exhibit poor selectivity, leading to undesirable side effects. A significant challenge in designing effective CA inhibitors is achieving balanced isoform selectivity, prompting the exploration of new chemotypes. This review compiles recent strategies employed by various researchers in developing CAIs across different structural classes, including pyrazoline, quinoline, imidazole, oxadiazole, pyrimidine, coumarin, chalcone, rhodanine, phthalazine, triazole, isatin, and indole. Additionally, the review summarizes structure-activity relationship (SAR) analyses, isoform selectivity evaluations, along with mechanistic and in silico investigations. Insights derived from SAR studies provide crucial directions for the rational design of next-generation heterocyclic CA inhibitors, with improved therapeutic efficacy and reduced side effects. To the best of our knowledge, for the first time, we have comprehensively summarized all known isoforms of CA in relation to various heterocyclic motifs. This review examines the use of different heterocycles as CA inhibitors, drawing on research published over the past 11 years. It offers a valuable resource for early-career researchers, encouraging further exploration of synthetic heterocycles in the development of CA inhibitors.

Dynamics of small molecule-enzyme interactions: Novel benzenesulfonamides as multi-target agents endowed with inhibitory effects against some metabolic enzymes

In contemporary medicinal chemistry, employing a singular small molecule to concurrently multi-target disparate molecular entities is emerging as a potent strategy in the ongoing battle against metabolic disease. In this study, we present the meticulous design, synthesis, and comprehensive biological evaluation of a novel series of 1,2,3-triazolylmethylthio-1,3,4-oxadiazolylbenzenesulfonamide derivatives (8a-m) as potential multi-target inhibitors against human carbonic anhydrase (EC.4.2.1.1, hCA I/II), α-glycosidase (EC.3.2.1.20, α-GLY), and α-amylase (EC.3.2.1.1, α-AMY). Each synthesized sulfonamide underwent rigorous assessment for inhibitory effects against four distinct enzymes, revealing varying degrees of hCA I/II, a-GLY, and a-AMY inhibition across the tested compounds. hCA I was notably susceptible to inhibition by all compounds, demonstrating remarkably low inhibition constants (KI) ranging from 42.20 ± 3.90 nM to 217.90 ± 11.81 nM compared to the reference standard AAZ (KI of 439.17 ± 9.30 nM). The evaluation against hCA II showed that most of the synthesized compounds exhibited potent inhibition effects with KI values spanning the nanomolar range 16.44 ± 1.53-70.82 ± 4.51 nM, while three specific compounds, namely 8a-b and 8d, showcased lower inhibitory potency than other derivatives that did not exceed that of the reference drug AAZ (with a KI of 98.28 ± 1.69 nM). Moreover, across the spectrum of synthesized compounds, potent inhibition profiles were observed against diabetes mellitus-associated α-GLY (KI values spanning from 0.54 ± 0.06 μM to 5.48 ± 0.50 μM), while significant inhibition effects were noted against α-AMY, with IC50 values ranging between 0.16 ± 0.04 μM and 7.81 ± 0.51 μM) compared to reference standard ACR (KI of 23.53 ± 2.72 μM and IC50 of 48.17 ± 2.34 μM, respectively). Subsequently, these inhibitors were evaluated for their DPPH· and ABTS+· radical scavenging activity. Moreover, molecular docking investigations were meticulously conducted within the active sites of hCA I/II, α-GLY, and α-AMY to provide comprehensive elucidation and rationale for the observed inhibitory outcomes.

Exploring rhodanine linked enamine-carbohydrazide derivatives as mycobacterial carbonic anhydrase inhibitors: Design, synthesis, biological evaluation, and molecular docking studies

With the rise of multidrug-resistant tuberculosis, the imperative for an alternative and superior treatment regimen, incorporating novel mechanisms of action, has become crucial. In pursuit of this goal, we have developed and synthesized a new series of rhodanine-linked enamine-carbohydrazide derivatives, exploring their potential as inhibitors of mycobacterial carbonic anhydrase. The findings reveal their efficacy, displaying notable selectivity toward the mycobacterial carbonic anhydrase 2 (mtCA 2) enzyme. While exhibiting moderate activity against human carbonic anhydrase isoforms, this series demonstrates promising selectivity, positioning these compounds as potential antitubercular agents. Compound 6d was the best one from the series with a Ki value of 9.5 µM toward mtCA 2. Most of the compounds displayed moderate to good inhibition against the Mtb H37Rv strain; compound 11k showed a minimum inhibitory concentration of 1 µg/mL. Molecular docking studies revealed that compounds 6d and 11k show metal coordination with the zinc ion, like classical CA inhibitors.

Chemistry of heterocycles as carbonic anhydrase inhibitors: A pathway to novel research in medicinal chemistry review

Nowadays, the scientific community has focused on dealing with different kinds of diseases by exploring the chemistry of various heterocycles as novel drugs. In this connection, medicinal chemists identified carbonic anhydrases (CA) as one of the biologically active targets for curing various diseases. The widespread distribution of these enzymes and the high degree of homology shared by the different isoforms offer substantial challenges to discovering potential drugs. Medicinal and synthetic organic chemists have been continuously involved in developing CA inhibitors. This review explored the chemistry of different heterocycles as CA inhibitors using the last 11 years of published research work. It provides a pathway for young researchers to further explore the chemistry of a variety of synthetic as well as natural heterocycles as CA inhibitors.

Caffeic acid and ferulic acid can improve toxicological damage caused by iron overload mediated by carbonic anhydrase inhibition

The iron ion is an essential element for most forms of life, however, it can damage biological systems when found in free form. Chelation therapy is very important, but it is precarious. Caffeic and ferulic acid are antioxidant compounds with many properties described in research such as anti-inflammatory, antiobesogenic, antithrombotic, vasodilator, and anti-tumor. The aim of the study was to evaluate presenting an in silico approach on the toxicity and bioavailability of caffeic and ferulic acid, subsequently, evaluating them in an iron overload model in vivo and providing a pharmacophoric model through molecular docking. The predictive in silico test did not show relevant toxicity of the compounds, therefore, the in vivo test was performed. The rats received dextran iron and the test groups received caffeic and ferulic acid orally for six weeks. Biochemical, hematological parameters, and tissue oxidative stress marker were analyzed. The experimental model showed increased serum iron levels and changes in several serum parameters such as glucose (215.8 ± 20.3 mg/dL), ALT (512.2 ± 128.7 U/L), creatine kinase (186.8 ± 30.1 U/L), and creatine kinase isoform MB (373.3 ± 69.7 U/L). Caffeic acid and, to a lessed degree, ferullic acid, attenuated the effects of iron overload on the rat serum biochemical parameters. Docking showed a pharmacophoric model where carbonic anhydrase interacted with the test molecules and caffeic acid showed less energy expenditure in this interaction. The results illustrate a new therapeutic action of phenolic compounds on iron overload. The possible interference of carbonic anhydrase in iron metabolism needs to be elucidated.

New 3-amino-2-thioxothiazolidin-4-one-based inhibitors of acetyl- and butyryl-cholinesterase: synthesis and activity

Aim: 2-Thioxothiazolidin-4-one represents a versatile scaffold in drug development. The authors used it to prepare new potent acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitors that can be utilized, e.g., to treat Alzheimer's disease. Materials & methods: 3-Amino-2-thioxothiazolidin-4-one was modified at the amino group or active methylene, using substituted benzaldehydes. The derivatives were evaluated for inhibition of AChE and BChE (Ellman's method). Results & conclusion: The derivatives were obtained with yields of 52-94%. They showed dual inhibition with IC50 values from 13.15 μM; many compounds were superior to rivastigmine. The structure-activity relationship favors nitrobenzylidene and 3,5-dihalogenosalicylidene scaffolds. AChE was inhibited noncompetitively, whereas BChE was inhibited with a mixed type of inhibition. Molecular docking provided insights into molecular interactions. Each enzyme is inhibited by a different binding mode.

Design, synthesis, and structure-activity studies of new rhodanine derivatives as carbonic anhydrase II, IX inhibitors

Rhodanine and its derivatives are an important class of heterocycles with diverse biological properties, including anticancer, antibacterial, and anti-mycobacterial activities. In the present work, four series of new Rhodanine derivatives were synthesized and evaluated for their inhibitory activity against carbonic anhydrase I, II, IX, and XII isoforms. Interestingly, the tested compounds exhibited good inhibitory activity against the cytosolic isoform human carbonic anhydrase (hCA) II and tumor-associated hCA IX. While the Rhodanine-benzylidene derivatives (3a-l) and Rhodanine-hydrazine derivatives (6a-e) are found to be selective against hCA II, the Rhodanine-N-carboxylate derivatives (8a-d) are found to be highly selective toward hCA IX. The Rhodanine-linked isoxazole and 1,2,4-oxadiazole derivatives (8ba, 8da, and 8db) exhibited inhibitory activity against hCA II and hCA IX. Among the tested compounds, 3b, 3j, 6d, and 8db were found to inhibit hCA II with Ki values of 9.8, 46.4, 7.7, and 4.7 µM, respectively. Furthermore, their mechanism of action is supported by molecular docking studies. Notably, the synthesized Rhodanine derivatives belong to a nonsulfonamide class of carbonic anhydrase inhibitors.

Design, in Silico Studies and Biological Evaluation of New Chiral Thiourea and 1,3-Thiazolidine-4,5-dione Derivatives

In this study, new chiral thiourea and 1,3-thiazolidine-4,5-dione derivatives were synthesized, it was aimed to evaluate the various biological activities and molecular docking of these compounds. Firstly, the new thioureas (1-16) were obtained by reacting 1-naphthylisothiocyanate with different chiral amines. Then, the chiral thioureas were cyclized with oxalyl chloride to obtain 1,3-thiazolidine-4,5-dione derivatives (17-32). All compounds were evaluated with several in vitro antioxidant and enzyme inhibition activities. Compound 30 was the most active compound against AChE, with a value of IC50 =8.09±0.58 μM. On the other hand, all compounds were tested in silico absorption, distribution, metabolism, and excretion (ADME) assays to better understand their bioavailability. These physicochemical properties, pharmacokinetics, and drug-likeness of all compounds were calculated using SwissADME. Furthermore, according to molecular docking analyses compound 30 exhibited significant binding affinities for all enzymes. Based on our overall observations, compound 30 could be recommended as a potential lead for the therapuetic of Alzheimer's.

Syntheses, in vitro, and in silico studies of rhodanine-based schiff bases as potential α-amylase inhibitors and radicals (DPPH and ABTS) scavengers

A two-step reaction method was used to synthesize a series of rhodanine-based Schiff bases (2-33) that were characterized using spectroscopic techniques. All compounds were assessed for α-amylase inhibitory and radical scavenging (DPPH and ABTS) activities. In comparison to the standard acarbose (IC50 = 9.08 ± 0.07 µM), all compounds demonstrated good to moderate α-amylase inhibitory activity (IC50 = 10.91 ± 0.08-61.89 ± 0.102 µM). Compounds also demonstrated significantly higher DPPH (IC50 = 10.33 ± 0.02-96.65 ± 0.03 µM) and ABTS (IC50 = 12.01 ± 0.12-97.47 ± 0.13 µM) radical scavenging activities than ascorbic acid (DPPH, IC50 = 15.08 ± 0.03 µM; ABTS, IC50 = 16.09 ± 0.17 µM). The limited structure-activity relationship (SAR) suggests that the position and nature of the substituted groups on the phenyl ring have a vital role in varying inhibitory potential. Among the series, compounds with an electron-withdrawing group at the para position showed the highest potency. Kinetic studies revealed that the compounds followed a competitive mode of inhibition. Molecular docking results are found to agree with experimental findings, showing that compounds reside in the active pocket due to the main rhodanine moiety.

Rhodanine derivatives: An insight into the synthetic and medicinal perspectives as antimicrobial and antiviral agents

Rhodanine or 2-Thioxothiazolidin-4-one is a privileged heterocyclic compound offering a wide opportunity for structural modification, lead development, and modification. It is one of the highly decorated scaffolds in the drug discovery process. Rhodanine derivatives possess a plethora of biological activities due to their ability to interact with a diverse range of protein targets, which provide tremendous opportunities to discover new drugs with different modes of action. The most common strategy for developing novel rhodanine derivatives is the introduction of structurally diverse substituents at the C-5 or N-3, or both positions. Since the inception of Epralestat into the market in 1992, the exploration of rhodanine-3-acetic acids has led to the development of novel leads against different biological targets such as MRSA, HHV-6, Mycobacterial tuberculosis, dengue, etc. In the current pandemic era, some rhodanine compounds have been explored against SARS-CoV-2. In recent years, rhodanine and its derivatives have witnessed significant progress in developing new drug leads as potential antimicrobial and antiviral agents. Different synthetic methodologies and recent developments in the medicinal chemistry of rhodanine derivatives, including biological activities, their mechanistic aspects, structure-activity relationships, and in silico findings, have been compiled in the present review. This article will benefit the scientific community and offer perspectives on how these scaffolds as privileged structures might be exploited in the future for rational design and discovery of rhodanine-based bio-active molecules.

Novel Thiopyrano[2,3-d]thiazole-pyrazole Hybrids as Potential Nonsulfonamide Human Carbonic Anhydrase IX and XII Inhibitors: Design, Synthesis, and Biochemical Studies

In recent years, molecular hybridization strategies have developed into a potent strategy for drug discovery. A series of novel thiopyrano[2,3-d]thiazoles linked to the pyrazole moiety was designed and developed as anticancer agents by a molecular hybridization. Target compounds were synthesized and characterized by spectroscopic tools as well as X-ray crystallography analysis as in the case of thiopyrano[2,3-d]thiazole derivative 5a. The MTT assay was used to demonstrate the in vitro efficacy of compounds 5a-g and 7a-j on MCF-7 and HePG-2. The results showed that some cycloadducts such as bromophenyl-4-thioxo-2-thiazolidinone 3e, 4-methylphenyl derivative of thiopyrano[2,3-d]thiazole 5d, and 6-substituted-thiopyrano[2,3-d]thiazoles 7e-j displayed good to excellent IC₅₀ in the range of 10.08 ± 1.5 to 25.95 ± 2.8 μg/mL against the MCF-7 cell line and from 7.83 ±2.1 to 13.37 ± 1.2 μg/mL against the HePG-2 cell line. To explore the enzymatic tests for isozymes hCAIX and hCAXII, the most promising eight compounds 3e, 5d, and 7e-j with IC₅₀ ranging from 7.83 ± 2.1 to 25.95 ± 2.8 μM were chosen. Compound 7e exhibited an IC₅₀ (0.067 ± 0.003 μM) similar to that of the standard drug AZA against CAIX (0.059 ± 0.003 μM)). For CAXII, the compound 7i had an IC₅₀ equal to 0.123 ± 0.007 μM compared to that of AZA (0.083 ± 0.005 μM). In addition, using flow cytometry, cell cycle analysis and apoptosis studies in HePG-2 were performed for the two potent anticancer and selective carbonic anhydrase agents (7e and 7i). An enzymatic assay of these two compounds against caspase-9 was also examined. Interestingly, the molecular docking studies revealed that compounds 7e and 7i successfully embedded themselves in the active pockets of the CAIX and CAXII enzymes through different interactions. Overall, the novel thiopyrano[2,3-d]thiazole-pyrazole hybrids (7e and 7i) were suggested to be potent and selective inhibitors of CAIX and CAXII.

Design, Synthesis and Biological Assessment of Rhodanine-Linked Benzenesulfonamide Derivatives as Selective and Potent Human Carbonic Anhydrase Inhibitors

A novel series of twenty-five rhodamine-linked benzenesulfonamide derivatives (7a-u and 9a-d) were synthesized and screened for their inhibitory action against four physiologically relevant human (h) carbonic anhydrase (CA) isoforms, namely hCA I, hCA II, hCA IX, and hCA XII. All the synthesized molecules showed good to excellent inhibition against all the tested isoforms in the nanomolar range due to the presence of the sulfonamide as a zinc binding group. The target compounds were developed from indol-3-ylchalcone-linked benzenesulfonamide where the indol-3-ylchalcone moiety was replaced with rhodanine-linked aldehydes or isatins to improve the inhibition. Interestingly, the molecules were slightly more selective towards hCA IX and XII compared to hCA I and II. The most potent and efficient ones against hCA I were 7h (K_I 22.4 nM) and 9d (K_I 35.8 nM) compared to the standard drug AAZ (K_I 250.0 nM), whereas in case of hCA II inhibition, the derivatives containing the isatin nucleus as a tail were preferred. Collectively, all compounds were endowed with better inhibition against hCA IX compared to AAZ (K_I 25.8 nM) as well as strong potency against hCA XII. Finally, these newly synthesized molecules could be taken as potential leads for the development of isoform selective hCA IX and XII inhibitors.

Protective effect of naringin against oxaliplatin-induced peripheral neuropathy in rats: A behavioral and molecular study

Oxaliplatin (OXL) is a chemotherapeutic drug used for metastatic and other types of cancer, but it causes peripheral neuropathy as a dose-limiting side effect. Herein, we used the rat model of OXL-induced peripheral neuropathy to demonstrate the protective effects of naringin (NRG) in this neuropathy. In this study, rats were injected with OXL (4 mg/kg, body weight, i.p.) in 5% glucose solution 30 min after oral administration of NRG (50 and 100 mg/kg, body weight) on the 1st, 2nd, 5th, and 6th days. OXL caused sensory and motor neuropathy (as revealed by the hot plate, tail flick, rota-rod, and cold hyperalgesia tests) in the sciatic nerve of rats. Coadministration of oral NRG alleviated OXL-induced sensory and motor neuropathy. Levels of superoxide dismutase, catalase, glutathione peroxidase, nuclear factor erythroid 2-related factor 2, Heme oxygenase-1, nuclear factor-κ B, tumor necrosis factor-α, interleukin-1β, Bax, Bcl-2, caspase-3, paraoxonase, mitogen-activated protein kinase 14, neuronal nitric oxide synthase (nNOS), acetylcholinesterase, and arginase 2 in the sciatic nerve tissues were assessed by real-time polymerase chain reaction. Moreover, the protein levels of caspase-3, Bax, Bcl-2, intercellular adhesion molecules-1, glial fibrillary acidic protein, and nNOS were examined by Western blot analysis. NRG treatment significantly improved all the above-mentioned parameters and reduced OXL-induced oxidative stress, inflammation, and apoptosis in the sciatic nerve tissue. In conclusion, this study demonstrated that NRG significantly attenuated OXL-induced peripheral neuropathy and might be considered as a new protective agent to prevent the OXL-induced peripheral neuropathy.

Synthesis and some enzyme inhibition effects of isoxazoline and pyrazoline derivatives including benzonorbornene unit

Four new and four known isoxazoline derivatives were synthesized from the reactions of benzonorbornadiene with nitrile oxides formed from the corresponding benzaldehydes. Three new and one known pyrazoline derivatives were also synthesized from the reactions of the benzonorbornadiene with nitrile imines formed from the corresponding compounds. The synthesized nitrogen-based novel heterocyclic compounds were evaluated against the human carbonic anhydrase isoenzymes I and II (hCA I and hCA II), acetylcholinesterase (AChE), and butyrylcholinesterase (BChE) enzymes. The synthesized nitrogen-based novel heterocyclic compounds showed IC₅₀ values in the range of 2.69-7.01 against hCA I, 2.40-4.59 against hCA II, 0.81-1.32 µM against AChE, and 20.83-1.70 µM against BChE enzymes. On the contrary, nitrogen-based novel heterocyclic compounds demonstrated K_i values between 2.93 ± 0.59-8.61 ± 1.39 against hCA I, 2.05 ± 0.62-4.97 ± 0.95 against hCA II, 0.34 ± 0.02-0.92 ± 0.17 nM against AChE, and 0.50 ± 0.04-1.20 ± 0.16 µM against BChE enzymes. The synthesized nitrogen-based novel heterocyclic compounds exhibited effective inhibition profiles against both indicated metabolic enzymes. These results may contribute to the development of new drugs particularly to treat some disorders, which are widespread in the world including glaucoma and Alzheimer's diseases.

Cholinesterases, carbonic anhydrase inhibitory properties and in silico studies of novel substituted benzylamines derived from dihydrochalcones

A series of novel urea, sulfamide and N,N-dipropargyl substituted benzylamines were synthesized from dihydrochalcones. The synthesized compounds were evaluated for their cholinesterases and carbonic anhydrase inhibitory actions. The known dihydrochalcones were converted into four new benzylamines via reductive amination. N,N-Dipropargylamines, ureas and sulfamides were synthesized following the reactions of benzylamines with propargyl bromide, N,N-dimethyl sulfamoyl chloride and N,N-dimethyl carbamoyl chloride. The novel substituted benzylamines derived from dihydrochalcones were evaluated against some enzymes such as human erythrocyte carbonic anhydrase I and II isoenzymes (hCA I and hCA II), acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). The novel substituted benzylamines derived from dihydrochalcones exhibited K_i values in the range of 0.121-1.007 nM on hCA I, and 0.077-0.487 nM on hCA II closely related to several pathological processes. On the other hand, K_i values were found in the range of 0.112-0.558 nM on AChE, 0.061-0.388 nM on BChE. As a result, novel substituted benzylamines derived from dihydrochalcones showed potent inhibitory profiles against indicated metabolic enzymes. In addition, Induced-Fit Docking (IFD) simulations and ADME prediction studies have also been carried out to elucidate the inhibition mechanisms and drug-likeness of the synthesized compounds. Therefore, these results can make significant contributions to the treatment of some global diseases, especially Alzheimer's diseases and glaucoma, and the development of new drugs.

The Importance of Rhodanine Scaffold in Medicinal Chemistry: A Comprehensive Overview

After the clinical use of epalrestat that contains a rhodanine ring, in type II diabetes mellitus and diabetic complications, rhodanin-based compounds have become an important class of heterocyclic in the field of medicinal chemistry. Various modifications to the rhodanine ring have led to a broad spectrum of biological activity of these compounds. Synthesis of rhodanine derivatives, depended on advenced throughput scanning hits, frequently causes potent and selective modulators of targeted enzymes or receptors, which apply their pharmacological activities through different mechanisms of action. Rhodanine-based compounds will likely stay a privileged scaffold in drug discovery because of different probability of chemical modifications of the rhodanine ring. We have, therefore reviewed their biological activities and structure activity relationship.

Synthesis and biological evaluation of new pyrazolebenzene-sulphonamides as potential anticancer agents and hCA I and II inhibitors

Cancer is a disease characterized by the continuous growth of cells without adherence to the rules that healthy normal cells obey. Carbonic anhydrase I and II (CA I and CA II) inhibitors are used for the treatment of some diseases. The available drugs in the market have limitations or side effects, which bring about the need to develop new drug candidate compound(s) to overcome the problems at issue. In this study, new pyrazole-sulphonamide hybrid compounds 4-[5-(1,3-benzodioxol-5-yl)-3-aryl-4,5-dihydro-1 H -pyrazol-1-yl]benzenesulphonamides (4a - 4j) were designed to discover new drug candidate compounds. The compounds 4a - 4j were synthesized and their chemical structures were confirmed using spectral techniques. The hypothesis tested was whether an introduction of methoxy and polymethoxy group(s) lead to an increased potency selectivity expression (PSE) value of the compound, which reflects cytotoxicity and selectivity of the compounds. The cytotoxicity of the compounds towards tumor cell lines were in the range of 6.7 – 400 µM. The compounds 4i (PSE₂ = 461.5) and 4g (PSE₁ = 193.2) had the highest PSE values in cytotoxicity assays. Ki values of the compounds were in the range of 59.8 ± 3.0 - 12.7 ± 1.7 nM towards hCA I and in the range of 24.1 ± 7.1 - 6.9 ± 1.5 nM towards hCA II. While the compounds 4b, 4f, 4g, and 4i showed promising cytotoxic effects, the compounds 4c and 4g had the inhibitory potency towards hCA I and hCA II, respectively. These compounds can be considered as lead compounds for further research.

ADME properties, bioactivity and molecular docking studies of 4-amino-chalcone derivatives: new analogues for the treatment of Alzheimer, glaucoma and epileptic diseases

In this study, in vitro inhibition effects of (E)-1-(4-aminophenyl)-3-(aryl) prop-2-en-1-one (4-amino-chalcones) derivatives (3a-o) on acetylcholinesterase (AChE) enzyme and human erythrocyte carbonic anhydrase I and II isoenzymes (hCA I- II) were investigated. And also, the biological activities of 4-amino-chalcone derivatives against enzymes which names are acetylcholinesterase (PDB ID: 1OCE), human Carbonic Anhydrase I (PDB ID: 2CAB), human carbonic anhydrase II (PDB ID: 3DC3), were compared. After the results obtained, ADME/T analysis was performed in order to use 4-amino-chalcone derivatives as a drug in the future. Effective inhibitors of carbonic anhydrase I and II isozymes (hCAI and II) and acetylcholinesterase (AChE) enzymes with Ki values in the range of 2.55 ± 0.35-11.75 ± 3.57 nM for hCA I, 4.31 ± 0.78-17.55 ± 5.86 nM for hCA II and 96.01 ± 25.34-1411.41 ± 32.88 nM for AChE, respectively, were the 4-amino-chalcone derivatives (3a-o) molecules.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40203-021-00094-x.

New Chalcone Derivatives with Pyrazole and Sulfonamide Pharmacophores as Carbonic Anhydrase Inhibitors

Background:

Compound containing sulfonamide, pyrazole and chalcone groups are important in medicinal chemistry. They have a wide range of biological activities, including carbonic anhydrase (CA) inhibitory activities.

Introduction:

Carbonic anhydrase I and II inhibitors are used for the treatment of diseases, such as retinal and cerebral edema (CA I), epilepsy, and glaucoma (CA II). However, the currently available drugs have some limitations or side effects. Thus, there is a need for new drug candidates to overcome these issues. In this study, a series of compounds, (E)-4-(4-(3-aryl)-3-oxoprop-1-en-1-yl)- 3-phenyl-1H-pyrazol-1-yl) benzenesulfonamides MS4-MS10, were designed to discover new CA inhibitors using a hybrid approach.

Methods:

Compounds MS4-MS10 were synthesized as shown in Scheme 1, and their chemical structures were confirmed by 1H NMR, 13C NMR, and HRMS spectra. The CAs (E.C.4.2.1.1) inhibitory effects of MS4-MS10 were tested on the hCA I and II isoenzymes using previously reported procedures.

Results:

The CA inhibitors MS4–MS10 gave IC50 values (nM) of 27.8–87.3 towards hCA I and 24.4–54.8 towards hCA II while the IC50 values for reference drug acetazolamide were 384.2 (hCA I) and 36.9 (hCA II). MS7 and MS9 exhibited 13.8 (hCA I) and 1.5 (hCA II) times more potent CA inhibition than the reference compound acetazolamide, respectively.

Conclusion:

MS7 (Ar: 2,4,5-trimethoxy phenyl) and MS9 (Ar: 3,4-dimethoxy phenyl) were the most promising compounds of our series with the lowest IC50 values towards hCA I and hCA II, respectively, and can be considered for further studies.

Probing 4-(diethylamino)-salicylaldehyde-based thiosemicarbazones as multi-target directed ligands against cholinesterases, carbonic anhydrases and α-glycosidase enzymes

With the fading of 'one drug-one target' approach, Multi-Target-Directed Ligands (MTDL) has become a central idea in modern Medicinal Chemistry. The present study aimed to design, develop and characterize a novel series of 4-(Diethylamino)-salicylaldehyde based thiosemicarbazones (3a-p) and evaluates their biological activity against cholinesterase, carbonic anhydrases and α-glycosidase enzymes. The hCA I isoform was inhibited by these novel 4-(diethylamino)-salicylaldehyde-based thiosemicarbazones (3a-p) in low nanomolar levels, the Ki of which differed between 407.73 ± 43.71 and 1104.11 ± 80.66 nM. Against the physiologically dominant isoform hCA II, the novel compounds demonstrated K_is varying from 323.04 ± 56.88 to 991.62 ± 77.26 nM. Also, these novel 4-(diethylamino)-salicylaldehyde based thiosemicarbazones (3a-p) effectively inhibited AChE, with Ki values in the range of 121.74 ± 23.52 to 548.63 ± 73.74 nM. For BChE, Ki values were obtained with in the range of 132.85 ± 12.53 to 618.53 ± 74.23 nM. For α-glycosidase, the most effective Ki values of 3b, 3k, and 3g were with Ki values of 77.85 ± 10.64, 96.15 ± 9.64, and 124.95 ± 11.44 nM, respectively. We have identified inhibition mechanism of 3b, 3g, 3k, and 3n on α-glycosidase AChE, hCA I, hCA II, and BChE enzyme activities. Hydrazine-1-carbothioamide and hydroxybenzylidene moieties of compounds play an important role in the inhibition of AChE, hCA I, and hCA II enzymes. Hydroxybenzylidene moieties are critical for inhibition of both BChE and α-glycosidase enzymes. The findings of in vitro and in silico evaluations indicate 4-(diethylamino)-salicylaldehyde-based thiosemicarbazone scaffold to be a promising hit for drug development for multifactorial diseases like Alzheimer's disease.

Effect and Mechanism of Encapsulation-Based Spores on Self-Healing Concrete at Different Curing Ages

It has become an intelligent and environmental protection method to repair concrete cracks based on microbial-induced calcium carbonate precipitation (MICP). However, due to the high-alkali environment in concrete, even the microbial spores with strong alkali resistance find it difficult to survive for a long time, which affects the long-term self-healing effect of concrete cracks. In this paper, low-alkali sulfo-aluminate cement (SC) was used as a carrier to encapsulate spores, and the effects of the spore group and microbial group on the basic performances of concrete were studied. Then, the area repair ratio, water permeability, the repair ratio of anti-chloride ion penetration, and ultrasonic velocity were used to evaluate the self-healing efficiency of cracks, and the self-healing effects of two kinds of microbial self-healing agents on concrete cracks with different curing ages were further studied. Moreover, the growth, enzyme activity, and microbial morphologies of spores with and without encapsulation immersed in the simulated pore solution of cement-based materials at different times were studied to discuss the protective effect of the carrier on spores. Compared with the reference group, the results showed that the addition of two microbial self-healing agents would slightly affect the basic performances of concrete, but both were within the control range of concrete materials. For the early-age cracks, the two kinds of microbial self-healing agents could achieve a good self-healing effect, but for the later-age cracks, the concrete cracks of the microbial group could still be repaired well, while the self-healing effect of the spore group was greatly reduced. Moreover, the white precipitates generated at the crack mouth were all calcite CaCO₃. In addition, the self-healing mechanism of different microbial self-healing agents on concrete cracks was discussed carefully. This study provides a new idea and method for the engineering application of microbial self-healing concrete.

Neuroprotective effect of chrysin on isoniazid-induced neurotoxicity via suppression of oxidative stress, inflammation and apoptosis in rats

Isoniazid (INH) is among the most important anti-tuberculosis agents widely prescribed. However, its clinical use is restricted due to its severe side effects associated with neurotoxicity. The aim of the present study was to investigate the neuroprotective effects of chrysin (CR), a natural antioxidant, against INH-induced neurotoxicity in rats. The rats were treated orally with INH (400 mg/kg body weight) alone or with CR (25 and 50 mg/kg body weight) for 7 consecutive days. INH administration significantly increased brain lipid peroxidation and resulted in a significant decrease in antioxidant biomarkers including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH). INH treatment also increased levels of nuclear factor kappa B (NF-κB), tumor necrosis factor-α (TNF-α), glial fibrillary acidic protein (GFAP) and activities of p38α mitogen-activated protein kinase (p38α MAPK) while decreasing levels of neural cell adhesion molecule (NCAM). Double immunofluorescence expressions of c-Jun N-terminal kinase (JNK) and Bcl-2 associated X protein (Bax) in brain tissues were increased after INH administration. Furthermore, INH increased mRNA expression levels of nuclear factor erythroid 2-related factor 2 (Nrf-2), heme oxygenase-1 (HO-1), NAD(P)H: quinone oxidoreductase 1 (NQO1), glutamate-cysteine ligase modifier subunit (Gclm), glutamate cysteine ligase catalytic subunit (Gclc), NF-κB, TNF-α, interleukin-1β (IL-1β), interleukin-6 (IL-6) and GFAP in rat brain tissues. Co-treatment with CR increased anti-oxidant capacity as well as regulated inflammation and apoptosis in brain. Additionally, molecular docking results showed that CR had the potential to interact with the active sites of TNF-α and NFκ-B. In conclusion, CR improved INH-induced brain oxidative damage, inflammation and apoptosis, possibly through their antioxidant properties.

Anti-Parkinson's Activity of Tribulus terrestris via Modulation of AChE, α-Synuclein, TNF-α, and IL-1β

Tribulus terrestris (T.T.) is a rich source of flavonoids and saponins, which have been reported to have neuroprotective and antioxidant potential. The current study was planned to investigate the anti-Parkinson's activity of T. terrestris methanol extract (TTME). It was hypothesized that TTME possessed antioxidant potential and can ameliorate Parkinson's disease (PD) via modulation of α-synuclein, acetylcholinesterase (AChE), TNF-α, and IL-1β. To test this hypothesis, in silico and in vivo studies were performed. The PD model in rats was prepared by giving haloperidol, 1 mg/kg, i.p. Rats were divided into six groups: control, disease control, standard, and treatment groups receiving TTME orally at 100, 300, and 1000 mg/kg dose levels for 21 days. Behavioral observations and biochemical analyses were done. The TTME modulatory effect on mRNA expression of α-synuclein, AChE, TNF-α, and interleukins in the brain homogenate was estimated by RT-PCR. Compounds detected in HPLC analysis disrupted the catalytic triad of AChE in in silico studies. Behavioral observations showed significant (p < 0.05) improvement in a reversal of catatonia, muscular strength, locomotor functions, stride length, and exploration in a dose-dependent manner (1000 >300 >100 mg/kg) of PD rats. Endogenous antioxidant enzyme levels CAT, SOD, GSH, and GPx were significantly restored at a high dose (p < 0.05) with a notable (p < 0.05) decrease in the MDA level in TTME-treated groups. TTME at a high dose significantly (p < 0.05) decreased the level of acetylcholinesterase. RT-PCR results are showing down-regulation in the mRNA expression levels of IL-1β, α -synuclein, TNF-α, and AChE in TTME-treated groups compared to the disease control group, indicating neuroprotection. It is concluded that TTME has potential to ameliorate the symptoms of Parkinson's disease.

The biological activities, molecular docking studies, and anticancer effects of 1-arylsuphonylpyrazole derivatives

This work is devoted to definition of the direction of reaction between 1-benzenesulfonylimino pyridinium chloride and α- or β-halo-containing sulfamides, chloroacetic acid, 1-chloro-2,3-dihydroxypropane, etc. The optimal conditions for the synchronous reaction of heterocyclization are determined. Benzenesulfonyliminopyridinium chloride was obtained to form pyrazolopyridines with 1,2-polarophiles, and pyridazine pyridines with 1,3-polarophiles. These novel derivatives were found as effective inhibitors of the α-glycosidase with K_i values in the range of 13.66 ± 2.63-60.63 ± 12.71 nM. The molecules (II-X) against enzyme were compared theoretically with the help of molecular docking to compare biological activities. The results were compared with the numerical values of the parameters obtained from molecular docking calculations and found to be in great agreement with the experimental results. However, ADME analysis of molecules was performed. Also, the compounds exhibited significant anticancer effect depending on the doses administered.Communicated by Ramaswamy H. Sarma.

Inhibition effects of some pesticides and heavy metals on carbonic anhydrase enzyme activity purified from horse mackerel (Trachurus trachurus) gill tissues

The gill tissue is the main site of metabolic enzymes or compensation, with the kidney tissue playing a supporting role. At the gill tissue, carbonic anhydrase enzymes (CAs) catalyze the hydration of CO₂ to HCO₃^- and H⁺ for production to the H₂O. In this work, the CA enzyme was purified from horse mackerel (Trachurus trachurus) gill with a specific activity of 21,381.42 EU/mg, purification fold of 150.61, total activity of 2347.68 EU/mL, and a yield of 16.13% using sepharose 4B-L-tyrosine-sulfanilamide affinity gel chromatography. For recording the enzyme purity, gel electrophoresis was performed, and single band was seen. The molecular weight of this enzyme was found approximately 35 kDa. Also, the inhibitory effects of different pesticides such as thiram, clofentezine, propineb, deltamethrin, azoxystrobin, and thiophanate and heavy metal ions such as Fe²⁺, Cu²⁺, Co²⁺, Pb²⁺ Hg²⁺, and As³⁺ on horse mackerel gill tissue CA enzyme activities were investigated. Our results indicated that these pesticides and metal ions showed inhibitory effects at low nanomolar and millimolar concentrations for fish gill CA enzymes, respectively.

Synthesis, Molecular Modeling of Novel Substituted Pyridazinones and their Vasorelaxant Activities

BACKGROUND

Hypertension, one of the most common cardiovascular diseases that can cause coronary disease, stroke, myocardial infarction, and sudden death, it is the major contributor to cardiac failure as well as renal insufficiency.

OBJECTIVES

As there are many cardio-active pyridazinone-base derivatives in clinical use, therefore, we aimed to synthesize a new series of pyridazin-3-ones and evaluate their vasorelaxant activity.

METHODS

A new series of synthesized compounds were carried out first by the synthesis of 6- flouroarylpyridazinones by cyclization of 3-(4-flourobenzoyl) propionic acid with hydrazine hydrate or arylhydrazines to provide the corresponding pyridazinone derivatives 2a-d. Mannich reaction was performed using morpholine or piperidine formaldehyde to obtain compounds 3a,b. On the other hand, reaction of 2a with various chloroacetamide intermediates, in dimethylformamide and potassium carbonate as a catalyst, afforded the target compounds 5a-c. The aromatic acid hydrazide intermediates 6a-g were prepared in 50-90% yield, by reacting to the prepared esters with hydrazine hydrate under reflux in ethanol. The two compounds 8a,b were prepared via condensation of 7a,b with ethyl chloroacetate in dry acetone. Finally, the target 2,4,6-trisubstituted pyridazinones 9a-c derivatives were obtained by the reaction of 7a with the appropriate aromatic aldehyde or substituted acetophenones. The new compounds were then evaluated for their vasorelaxant properties using isolated thoracic rat aortic rings. In addition, a homology model was built and molecular modeling simulation of these compounds into the active sites of the newly created α1a-adrenoceptor model was performed in order to predict and rationalize their affinities toward this receptor.

RESULTS

Among these compounds; 5a was the most potent, it exhibited approximately two-times the activity of prazosin (IC50 = 0.250, 0.487 mmol, respectively) also, fourteen compounds were more potent than prazosin.

Novel functionally substituted esters based on sodium diethyldithiocarbamate derivatives: Synthesis, characterization, biological activity and molecular docking studies

Alkylation of sodium diethyldithiocarbamate with allyl-2-chloroacetate, allyl-3-chloropropionate, chloromethyl-2-(tetrahydrofuran-2-yl)acetate, and 4-(chloromethyl)-1,3-dioxolane in the aqueous medium synthesized functionally substituted esters of N, N-dietyleditiocarbamic acid (M1-M4). Most active compounds were docked into the catalytic active site of the enzyme. We identified that acetate moiety for inhibition of hCA I, hCA II, and α-glycosidase and dioxolane and thiocarbamic acid moieties for inhibition of AChE and BChE enzymes are very important. The hCA I isoform was inhibited by these novel functionally substituted esters based on sodium diethyldithiocarbamate derivatives (M1-M4) in low micromolar levels, the Ki of which differed between 48.03 ± 9.77 and 188.42 ± 46.08 µM. Against the physiologically dominant isoform hCA II, the novel compounds demonstrated K_is varying from 57.33 ± 6.21 to 174.34 ± 40.72 µM. Also, these novel derivatives (M1-M4) effectively inhibited AChE, with Ki values in the range of 115.42 ± 12.44 to 243.22 ± 43.65 µM. For BChE Ki values were found in the range of 94.33 ± 9.14 to 189.45 ± 35.88 µM. For α-glycosidase the most effective Ki values of M4 and M3 were with Ki values of 32.86 ± 7.88 and 37.63 ± 4.08 µM, respectively.