The Bioactivity of Thiazolidin-4-Ones: A Short Review of the Most Recent Studies

Silver(I) Octanuclear Complexes Containing N'-(4-Oxotiazolidin-2-Iliden)picolinohydrazonamide and Nitrate as Bridge Ligands. An Example of Solvatomorphism?

The versatile coordination chemistry of (2Z,N'E)-N'-(4-oxothiazolidin-2-ylidene)picolinohydrazonamide (HAmDHotaz) facilitated the synthesis of new complexes with different silver(I) salts. This paper describes the synthesis and characterization, through elemental analysis and spectroscopic techniques (when solubility permits), of a series of compounds that illustrate the coordinative and structural diversity achievable with the HAmDHotaz ligand. Five silver clusters containing the [Ag8(AmDHotaz)4]4+ nucleus were structurally analyzed by single-crystal X-ray diffraction and were found to exhibit solvomorphism. The compositions of these are [Ag8(AmDHotaz)4(NO3)3(MeOH)(H2O)](NO3)·MeOH·7.5H2O (1), {[Ag8(AmDHotaz)4(NO3)3(H2O)2](NO3)·9.5(H2O)}n (2), {[Ag8(AmDHotaz)4(NO3)3(H2O)2](NO3)·11.5(H2O)}n (2a), {[Ag8(AmDHotaz)4(NO3)2(H2O)2](NO3)(OH)·6H2O}n (3), and {[Ag8(AmDHotaz)4(NO3)2(H2O)](NO3)(OH)·4.5H2O}n (3a). Argentophilic interactions are present in each of the octanuclear structures, where Ag···Ag distances range from 2.828(2) to 2.986(1) Å. These distances are influenced by crystal packing, determined by the counterion and solvent molecules in the structure. In the solvatomorphs, solvent molecules were observed to be disordered. Various hydrogen-bonding interactions, such as N-H···O-N, O-H···O, N-H···O═C, C-H···O-N, and π-π stacking interactions, contribute to the crystal packing. The influence of these weak interactions on the crystal packing was further analyzed using DFT calculations and Bader's theory of atoms-in-molecules, with a focus on argentophilic interactions and Ag···S interactions.

New Thiazolidine-4-One Derivatives as SARS-CoV-2 Main Protease Inhibitors

It has been more than four years since the first report of SARS-CoV-2, and humankind has experienced a pandemic with an unprecedented impact. Moreover, the new variants have made the situation even worse. Among viral enzymes, the SARS-CoV-2 main protease (Mpro) has been deemed a promising drug target vs. COVID-19. Indeed, Mpro is a pivotal enzyme for viral replication, and it is highly conserved within coronaviruses. It showed a high extent of conservation of the protease residues essential to the enzymatic activity, emphasizing its potential as a drug target to develop wide-spectrum antiviral agents effective not only vs. SARS-CoV-2 variants but also against other coronaviruses. Even though the FDA-approved drug nirmatrelvir, a Mpro inhibitor, has boosted the antiviral therapy for the treatment of COVID-19, the drug shows several drawbacks that hinder its clinical application. Herein, we report the synthesis of new thiazolidine-4-one derivatives endowed with inhibitory potencies in the micromolar range against SARS-CoV-2 Mpro. In silico studies shed light on the key structural requirements responsible for binding to highly conserved enzymatic residues, showing that the thiazolidinone core acts as a mimetic of the Gln amino acid of the natural substrate and the central role of the nitro-substituted aromatic portion in establishing π-π stacking interactions with the catalytic His-41 residue.

In vitro and in vivo evaluation of the antimicrobial, antioxidant, cytotoxic, hemolytic activities and in silico POM/DFT/DNA-binding and pharmacokinetic analyses of new sulfonamide bearing thiazolidin-4-ones

In this work, Schiff bases and Thiazolidin-4-ones, were synthesized using Sonication and Microwave techniques, respectively. The Schiff base derivatives (3a-b) were synthesized via the reaction of Sulfathiazole (1) with benzaldehyde derivatives (2a-b), followed by the synthesis of 4-thiazoledinone (4a-b) derivatives by cyclizing the synthesized Schiff bases through thioglycholic acid. All the synthesized compounds were characterized by spectroscopic techniques such as FT IR, NMR and HRMS. The synthesized compounds were tested for their in vitro antimicrobial and antioxidant and in vivo cytotoxicity and hemolysis ability. The synthesized compounds displayed better antimicrobial and antioxidant activity and low toxicity in comparison to reference drugs and negative controls, respectively. The hemolysis test revealed the compounds exhibit lower hemolytic effects and hemolytic values are comparatively low and the safety of compounds is in comparison with standard drugs. Theoretical calculations were carried out by using the molecular operating environment (MOE) and Gaussian computing software and observations were in good agreement with the in vitro and in vivo biological activities. Petra/Osiris/Molinspiration (POM) results indicate the presence of three combined antibacterial, antiviral and antitumor pharmacophore sites. The molecular docking revealed the significant binding affinities and non-bonding interactions between the compounds and Erwinia Chrysanthemi (PDB ID: 1SHK). The molecular dynamics simulation under in silico physiological conditions revealed a stable conformation and binding pattern in a stimulating environment. HighlightsNew series of Thaiazolidin-4-one derivatives have been synthesized.Sonication and microwave techniques are used.Antimicrobial, Antioxidant, cytotoxicity, and hemolysis activities were observed for all synthesized compounds.Molecular Docking and DFT/POM analyses have been predicted.Communicated by Ramaswamy H. Sarma.

Green design and synthesis of some novel thiazolidinone appended benzothiazole-triazole hybrids as antimicrobial agents

The global increase in bacterial resistance poses a significant threat, jeopardizing the effectiveness of antibiotics. Therefore, the development of new and efficient antimicrobial agents is pre-dominant. Taking this into consideration, in the present study, we designed and reported the facile synthesis of two novel series benzothiazole-triazole and thiazolidinone-appended benzothiazole-triazole hybrids using a molecular hybridization approach in a one-pot process. The synthesized compounds were tested for microbial growth inhibition against bacterial and fungal strains. Among all the synthetics, compounds derived from methoxyphenyl and heteroaromatic ring substitutions exhibited promising inhibitory activity. The current investigation has emphasized that benzothiazole-triazole hybrids incorporating thiazolidinone can be a promising and potent category of molecules with potential biological activities. This sustainable and eco-friendly protocol involves the metal-free, catalyst-free synthesis of bioactive scaffolds, which merges broad tolerance for functional groups with a short reaction time, resulting in good to excellent yields.

Synthesis and Tyrosinase Inhibitory Activity of Novel Benzimidazole/Thiazolidin-4-one Hybrid Derivatives

In this study, novel 3-(phenylamino)thiazolidin-4-one 2 a-d and 3-(phenyl)thiazolidin-4-one 3 a-g derivatives which are having benzimidazole moiety were synthesized and their tyrosinase inhibitory activity were investigated. The structures of the target compounds were elucidated using 1 H/13 C-NMR, IR and MS. The structure of 2 b was also characterized using HSQC NMR technique. Among the target compounds, 3 b-g demonstrated stronger tyrosinase inhibitory activity (IC50 values for 3 b-g ranged from 80.93 to 119.20 μM), compared to the positive control kojic acid (IC50 : 125.08 μM). With IC50 value of 80.93 μM, 5-(2-(4-(1H-benzimidazol-1-yl)phenyl)-4-oxothiazolidin-3-yl)-2-methylbenzenesulfonamide 3 g was found to be the most active derivative of the series. Molecular docking studies were conducted to elucidate the binding interactions between compounds and tyrosinase. The MTT assay studies used to determine the cytotoxicity of 3 b-g showed that 3 c, 3 d, 3 f and 3 g were not cytotoxic in the range of 0-200 μM. Considering its tyrosinase inhibitory activity and cytotoxic effect, 3 g exhibits promising potential for further research and development as a novel tyrosinase inhibitor.

Gastroprotective effect of rhodanine and 2,4-thiazolidinediones scaffolds in rat stomachs by contribution of anti-apoptotic (BCL-2) and tumor suppressor (P53) proteins

In recent times, the methods used to evaluate gastric ulcer healing worldwide have been based on visual examinations and estimating ulcer dimensions in experimental animals. In this study, the protective effect of rhodanine and 2,4-thiazolidinediones scaffolds compared to esomeprazole was investigated in an ethanol model of stomach ulcers in rats. Pretreatment with experimental treatments or esomeprazole prevented the development of ethanol-induced gastric ulcers. The severity of the lesions and injuries was significantly lower than that of vehicle (10% Tween 80) treated rats. Significant and excellent results were obtained with the compound 6 group, with inhibition percentage and ulcer area values of 97.8% and 12.8 ± 1.1 mm2, respectively. Synthesized compounds 2, 7 and 8 exhibited inhibition percentages and ulcer areas of 94.3% and 31.2 ± 1.1 mm2, 91. 3% and 48.1 ± 0. 8 mm2, 89. 5% and 57. 6 ± 1. 2 mm2, and 89. 1% and 60.3 ± 0. 8 mm2, respectively. These biological outcomes are consistent with the docking studies in which Compounds 7 and 8 showed remarkable binding site affinities toward human H+/K+-ATPase α protein (ID: P20648), rat H+/K+-ATPase α protein (ID: P09626), and Na+/K+-ATPase crystal structure (PDB ID:2ZXE) with binding site energies of - 10.7, - 9.0, and - 10.4 (kcal/mol) and - 8.7, - 8.5, and - 8.0 (kcal/mol), respectively. These results indicate that these test samples were as effective as esomeprazole. Likewise, immunohistochemical staining of antiapoptotic (BCL2) and tumor suppressor (P53) proteins showed strong positive marks in the10% Tween 80- treated group, opposing the mild staining results for the esomeprazole-treated group. Similarly, the staining intensity of the group treated with Compounds 2-8 was variable for both proteins.

Thiazolidin-4-Ones as a Promising Scaffold in the Development of Antibiofilm Agents-A Review

Thiazolidin-4-ones have a broad range of medical and clinical implementation, which is important for pharmaceutical and medicinal chemistry. This heterocyclic core has been reported to possess a diversity of bioactivities, including antimicrobial and antibiofilm-forming potential. The resistance of biofilms to antibiotics or disinfectants is a serious medical problem. Therefore, there is a natural need to discover new effective structures with properties that inhibit biofilm formation. This review aims to analyze the antibiofilm features of thiazolidin-4-ones described in the literature over the last two decades. The information gathered in this review could benefit the rational design of new effective antibiofilm small molecules with thiazolidin-4-one cores.

Serological Cross-Reaction between Six Thiadiazine by Indirect ELISA Test and Their Antimicrobial Activity

Malaria is a parasitic infection caused by a protozoon of the genus Plasmodium, transmitted to humans by female biting mosquitoes of the genus Anopheles. Chloroquine and its derivates have caused the parasite to develop drug resistance in endemic areas. For this reason, new anti-malarial drugs as treatments are crucial. This work aimed to evaluate the humoral response. with hyper-immune sera, of mice immunized with six derivatives of tetrahydro-(2H)-1,3,5-thiadiazine-2-thione (bis-THTT) by indirect ELISA test. The cross-reactivity between the compounds as antigens and their microbial activity on Gram-positive and Gram-negative bacteria was evaluated. The results of the humoral evaluation by indirect ELISA show that three bis-THTTs react with almost all of the above. Besides, three compounds used as antigens stimulate the BALB/c mice’s immune system. The best combination of two antigens as a combined therapy displays similar absorbances between the antigens in the mixture, showing similar recognition by antibodies and their compounds. In addition, our results showed that different bis-THTT presented antimicrobial activity on Gram-positive bacteria, mainly on Staphylococcus aureus strains, and no inhibitory activity was observed on the Gram-negative bacteria tested.

Parsing structural fragments of thiazolidin-4-one based α-amylase inhibitors: A combined approach employing in vitro colorimetric screening and GA-MLR based QSAR modelling supported by molecular docking, molecular dynamics simulation and ADMET studies

α-Amylase (EC.3.2.1.1) is a ubiquitous digestive endoamylase. The abrupt rise in blood glucose levels due to the hydrolysis of carbohydrates by α-amylase at a faster rate is one of the main reasons for type 2 diabetes. The inhibitors prevent the action of digestive enzymes, slowing the digestion of carbs and eventually assisting in the management of postprandial hyperglycemia. In the course of developing α-amylase inhibitors, we have screened 2-aryliminothiazolidin-4-one based analogs for their in vitro α-amylase inhibitory potential and employed various in silico approaches for the detailed exploration of the bioactivity. The DNSA bioassay revealed that compounds 5c, 5e, 5h, 5j, 5m, 5o and 5t were more potent than the reference drug (IC₆₀ value = 22.94 ± 0.24 μg mL^-1). The derivative 5o with -NO₂ group at both the rings was the most potent analog with an IC₆₀ value of 19.67 ± 0.20 μg mL^-1 whereas derivative 5a with unsubstituted aromatic rings showed poor inhibitory potential with an IC₆₀ value of 33.40 ± 0.15 μg mL^-1. The reliable QSAR models were developed using the QSARINS software. The high value of R²_ext = 0.9632 for model IM-9 showed that the built model can be applied to predict the α-amylase inhibitory activity of the untested molecules. A consensus modelling approach was also employed to test the reliability and robustness of the developed QSAR models. Molecular docking and molecular dynamics were employed to validate the bioassay results by studying the conformational changes and interaction mechanisms. A step further, these compounds also exhibited good ADMET characteristics and bioavailability when tested for in silico pharmacokinetics prediction parameters.

A comprehensive review on the antidiabetic attributes of thiazolidine-4-ones: Synthetic strategies and structure-activity relationships

The thiazolidine-4-one scaffold has recently emerged as a potential pharmacophore having clinical significance for medicinal chemists. This heterocyclic ring has been reported to possess a plethora of biological activities, including antidiabetic activity that has inspired researchers to integrate this core with different pharmacophoric fragments to design novel and effective antidiabetic leads. The antidiabetic activity has been observed due to the ability of the thiazolidine-4-one nucleus to interact with different biological targets, including peroxisome proliferator-activated receptor γ, protein tyrosine phosphatase 1B, aldose reductase, α-glucosidase, and α-amylase. The present review discusses the mode of action of thiazolidine-4-ones through these antidiabetic drug targets. This review attempts to summarize and analyze the recent developments with regard to the antidiabetic potential of thiazolidine-4-ones covering different synthetic strategies, structure-activity relationships, and docking studies reported in the literature. The significance of various structural modifications at C-2, N-3, and C-5 of the thiazolidine-4-one ring has also been discussed in this manuscript. This comprehensive compilation will provide an inevitable scope for the design and development of potential antidiabetic drug candidates having a thiazolidine-4-one core.

Evaluation of 5-[(Z)-(4-nitrobenzylidene)]-2-(thiazol-2-ylimino)-4-thiazolidinone (Les-6222) as Potential Anticonvulsant Agent

It was determined that the studied 5-[(Z)-(4-nitrobenzylidene)]-2-(thiazol-2-ylimino)-4-thiazolidinone (Les-6222) affects the cyclooxygenase pathway of the arachidonic acid cascade, the markers of damage to neurons on models of PTZ kindling. In the model of chronic epileptogenesis in mice (pentylenetetrazole kindling), a 4-thiazolidinone derivative showed high anticonvulsant activity, which is weaker than the effect of sodium valproate and higher than Celecoxib. The mentioned compound has a pronounced anti-inflammatory effect in the brain on the background of the PTZ kindling, reliably inhibiting COX-1 and COX-2. The predominant inhibition of COX-2 by 44.5% indicates this enzyme’s high selectivity of Les-6222. According to the molecular docking study results, the studied compound revealed the properties of COX-1/COX-2 inhibitor and especially 5-LOX/FLAP. The decreasing content of 8-isoprostane in the brain of mice of the Les-6222 group indicates a beneficial effect on cell membranes in the background of oxidative stress during the long-term administration of PTZ. In addition, Les-6222 significantly decreased the content of neuron-specific enolase, indicating neuroprotective properties in the background of chronic epileptogenesis. The obtained results experimentally substantiate the feasibility of further developing Les-6222 as a promising anticonvulsant agent.