Rhodanine derivatives as inhibitors of JSP-1

Recent advances in synthetic strategies and SAR of thiazolidin-4-one containing molecules in cancer therapeutics

Cancer is one of the life-threatening diseases accountable for millions of demises globally. The inadequate effectiveness of the existing chemotherapy and its harmful effects has resulted in the necessity of developing innovative anticancer agents. Thiazolidin-4-one scaffold is among the most important chemical skeletons that illustrate anticancer activity. Thiazolidin-4-one derivatives have been the subject of extensive research and current scientific literature reveals that these compounds have shown significant anticancer activities. This manuscript is an earnest attempt to review novel thiazolidin-4-one derivatives demonstrating considerable potential as anticancer agents along with a brief discussion of medicinal chemistry-related aspects of these compounds and structural activity relationship studies in order to develop possible multi-target enzyme inhibitors. Most recently, various synthetic strategies have been developed by researchers to get various thiazolidin-4-one derivatives. In this review, the authors highlight the various synthetic, green, and nanomaterial-based synthesis routes of thiazolidin-4-ones as well as their role in anticancer activity by inhibition of various enzymes and cell lines. The detailed description of the existing modern standards in the field presented in this article may be interesting and beneficial to the scientists for further exploration of these heterocyclic compounds as possible anticancer agents.

Design, Synthesis, Computational Investigations, and Antitumor Evaluation of N-Rhodanine Glycosides Derivatives as Potent DNA Intercalation and Topo II Inhibition against Cancer Cells

Nitrogen and sulfur glycosylation was carried out via the reaction of rhodanine (1) with α-acetobromoglucose 3 under basic conditions. Deacetylation of the protected nitrogen nucleoside 4 was performed with CH₃ONa in CH₃OH without cleavage of the rhodanine ring to afford the deprotected nitrogen nucleoside 6. Further, deacetylation of the protected sulfur nucleoside 5 was performed with CH₃ONa in CH₃OH with the cleavage of the rhodanine ring to give the hydrolysis product 7. The protected nitrogen nucleosides 11a-f were produced by condensing the protected nitrogen nucleoside 4 with the aromatic aldehydes 10a-f in C₂H₅OH while using morpholine as a secondary amine catalyst. Deacetylation of the protected nitrogen nucleosides 11a-f was performed with NaOCH₃/CH₃OH without cleavage of the rhodanine ring to afford the deprotected nitrogen nucleosides 12a-f. NMR spectroscopy was used to designate the anomers' configurations. To examine the electrical and geometric properties derived from the stable structure of the examined compounds, molecular modeling and DFT calculations using the B3LYP/6-31+G (d,p) level were carried out. The quantum chemical descriptors and experimental findings showed a strong connection. The IC₅₀ values for most compounds were very encouraging when evaluated against MCF-7, HepG2, and A549 cancer cells. Interestingly, IC₅₀ values for 11a, 12b, and 12f were much lower than those for Doxorubicin (7.67, 8.28, 6.62 μM): (3.7, 8.2, 9.8 μM), (3.1, 13.7, 21.8 μM), and (7.17, 2.2, 4.5 μM), respectively. Against Topo II inhibition and DNA intercalation, when compared to Dox (IC₅₀ = 9.65 and 31.27 μM), compound 12f showed IC₅₀ values of 7.3 and 18.2 μM, respectively. In addition, compound 12f induced a 65.6-fold increase in the rate of apoptotic cell death in HepG2 cells, with the cell cycle being arrested in the G2/M phase as a result. Additionally, it upregulated the apoptosis-mediated genes of P53, Bax, and caspase-3,8,9 by 9.53, 8.9, 4.16, 1.13, and 8.4-fold change, while it downregulated the Bcl-2 expression by 0.13-fold. Therefore, glucosylated Rhodanines may be useful as potential therapeutic candidates against cancer because of their topoisomerase II and DNA intercalation activity.

Therapeutic significance of molecular hybrids for breast cancer research and treatment

Worldwide, breast cancer is still a leading cause of cancer death in women. Indeed, over the years, several anti-breast cancer drugs have been developed; however, the complex heterogeneous nature of breast cancer disease reduces the applicability of conventional targeted therapies with the upsurge in side effects and multi-drug resistance. Molecular hybrids generated by a combination of two or more active pharmacophores emerged as a promising approach in recent years for the design and synthesis of anti-breast cancer drugs. The hybrid anti-breast cancer molecules are well known for their several advantages compared to the parent moiety. These hybrid forms of anti-breast cancer molecules demonstrated remarkable effects in blocking different pathways contributing to the pathogenies of breast cancer and improved specificity. In addition, these hybrids are patient compliant with reduced side effects and multi-drug resistance. The literature revealed that molecular hybrids are applied to discover and develop novel hybrids for various complex diseases. This review article highlights the recent progress (∼2018-2022) in developing molecular hybrids, including linked, merged, and fused hybrids, as promising anti-breast cancer agents. Furthermore, their design principles, biological potential, and future perspective are discussed. The provided information will lead to the development of novel anti-breast cancer hybrids with excellent pharmacological profiles in the future.

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.

Discovery of Cinnamylidene Derivative of Rhodanine with High Anthelmintic Activity against Rhabditis sp

The treatment of parasitic infections requires the application of chemotherapy. In view of increasing resistance to currently in-use drugs, there is a constant need to search for new compounds with anthelmintic activity. A series of 16 cinnamylidene derivatives of rhodanine, including newly synthesized methoxy derivatives (1-11) and previously obtained chloro, nitro, and diethylamine derivatives (12-16), was investigated towards anthelmintic activity. Compounds (1-16) were evaluated against free-living nematodes of the genus Rhabditis sp. In the tested group of rhodanine derivatives, only compound 2 shows very high biological activity (LC50 = 0.93 µg/µL), which is higher than the reference drug albendazole (LC50 = 19.24 µg/µL). Crystal structures of two compounds, active 2 and inactive 4, were determined by the X-ray diffraction method to compare molecular geometry and search for differences responsible for observed biological activity/inactivity. Molecular modelling and selected physicochemical properties prediction were performed to assess the potential mechanism of action and applied in the search for an explanation as to why amongst all similar compounds only one is active. We can conclude that the tested compound 2 can be further investigated as a potential anthelmintic drug.

Review of anticancer potentials and structure-activity relationships (SAR) of rhodanine derivatives

Rhodanine has been recognized as a privileged scaffold in medicinal chemistry due to its well-known ability to demonstrate a broad range of biological activities. The possibility of structural diversification has contributed to the significance of rhodanine structure in effective drug discovery and design. Many studies have confirmed the potential of rhodanine-derived compounds in the treatment of different types of cancer through the apoptosis induction mechanism. Furthermore, most of the rhodanine derivatives exhibited remarkable anticancer activity in the micromolar range while causing negligible cytotoxicity to normal cells. This review critically describes the anticancer activity profile of reported rhodanine compounds and the structure-activity relationships (SAR) to highlight the value of rhodanine as the core structure for future cancer drug development as well as to assist the researchers in rational drug design.

Design and Microwave Synthesis of New (5Z) 5-Arylidene-2-thioxo-1,3-thiazolinidin-4-one and (5Z) 2-Amino-5-arylidene-1,3-thiazol-4(5H)-one as New Inhibitors of Protein Kinase DYRK1A

Here, we report on the synthesis of libraries of new 5-arylidene-2-thioxo-1,3-thiazolidin-4-ones 3 (twenty-two compounds) and new 2-amino-5-arylidene-1,3-thiazol-4(5H)-ones 5 (twenty-four compounds) with stereo controlled Z-geometry under microwave irradiation. The 46 designed final compounds were tested in order to determine their activity against four representative protein kinases (DYR1A, CK1, CDK5/p25, and GSK3α/β). Among these 1,3-thiazolidin-4-ones, the molecules (5Z) 5-(4-hydroxybenzylidene)-2-thioxo-1,3-thiazolidin-4-one 3e (IC₅₀ 0.028 μM) and (5Z)-5-benzo[1,3]dioxol-5-ylmethylene-2-(pyridin-2-yl)amino-1,3-thiazol-4(5H)-one 5s (IC₅₀ 0.033 μM) were identified as lead compounds and as new nanomolar DYRK1A inhibitors. Some of these compounds in the two libraries have been also evaluated for their in vitro inhibition of cell proliferation (Huh7 D12, Caco2, MDA-MB 231, HCT 116, PC3, and NCI-H2 tumor cell lines). These results will enable us to use the 1,3-thiazolidin-4-one core as pharmacophores to develop potent treatment for neurological or oncological disorders in which DYRK1A is fully involved.

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.

Rhodanine-3-acetamide derivatives as aldose and aldehyde reductase inhibitors to treat diabetic complications: synthesis, biological evaluation, molecular docking and simulation studies

In diabetes, increased accumulation of sorbitol has been associated with diabetic complications through polyol pathway. Aldose reductase (AR) is one of the key factors involved in reduction of glucose to sorbitol, thereby its inhibition is important for the management of diabetic complications. In the present study, a series of seven 4-oxo-2-thioxo-1,3-thiazolidin-3-yl acetamide derivatives 3(a–g) were synthesized by the reaction of 5-(4-hydroxy-3-methoxybenzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl acetic acid (2a) and 5-(4-methoxybenzylidene)-4-oxo-2-thioxo-1,3-thiazolidin-3-yl acetic acid (2b) with different amines. The synthesized compounds 3(a–g) were investigated for their in vitro aldehyde reductase (ALR1) and aldose reductase (ALR2) enzyme inhibitory potential. Compound 3c, 3d, 3e, and 3f showed ALR1 inhibition at lower micromolar concentration whereas all the compounds were more active than the standard inhibitor valproic acid. Most of the compounds were active against ALR2 but compound 3a and 3f showed higher inhibition than the standard drug sulindac. Overall, the most potent compound against aldose reductase was 3f with an inhibitory concentration of 0.12 ± 0.01 µM. In vitro results showed that vanillin derivatives exhibited better activity against both aldehyde reductase and aldose reductase. The molecular docking studies were carried out to investigate the binding affinities of synthesized derivatives with both ALR1 and ALR2. The binding site analysis of potent compounds revealed similar interactions as were found by cognate ligands within the active sites of enzymes.

Targeting tubulin polymerization and DNA binding of 4-thiazolidinone–umbelliferone hybrids: synthesis and cytotoxicity evaluation

The discovery of a series of combretastatin A-4 inspired novel molecular hybrids of 4-thiazolidinone–umbelliferone as prominent cytotoxic agents was reported.

Design, synthesis, molecular docking and ADME studies of novel indole-thiazolidinedione derivatives and their antineoplastic activity as CDK6 inhibitors

Several indole-thiazolidinedione derivatives (9–24) were designed and synthesized as CDK6 inhibitors, and their anticancer activity was probed on the MCF-7 cell line and the effects on gene expression profiles were elucidated.

Synthesis of Novel Sulfamethaoxazole 4-Thiazolidinone Hybrids and Their Biological Evaluation

A search for potent antitubercular agents prompted us to design and synthesize sulfamethaoxazole incorporated 4-thiazolidinone hybrids (7a–l) by using a cyclocondensation reaction between 4-amino-N-(5-methylisoxazol-3-yl)benzenesulfonamide (4), aryl aldehyde (5a–l), and mercapto acetic acid (6) resulting in good to excellent yields. All the newly synthesized 4-thiazolidinone derivatives were screened for their in vitro antitubercular activity against M. Bovis BCG and M. tuberculosis H37Ra (MTB) strains. The compounds 7d, 7g, 7i, 7k, and 7l revealed promising antimycobacterial activity against M. Bovis and MTB strains with IC₉₀ values in the range of 0.058–0.22 and 0.43–5.31 µg/mL, respectively. The most active compounds were also evaluated for their cytotoxicity against MCF-7, HCT 116, and A549 cell lines and were found to be non-cytotoxic. Moreover, the synthesized compounds were also analyzed for ADME (absorption, distribution, metabolism, and excretion) properties and showed potential as good oral drug candidates.

Polyhalonitrobutadienes as Versatile Building Blocks for the Biotargeted Synthesis of Substituted N-Heterocyclic Compounds

Substituted nitrogen heterocycles are structural key units in many important pharmaceuticals. A new synthetic approach towards heterocyclic compounds displaying antibacterial activity against Staphylococcus aureus or cytotoxic activity has been developed. The selective synthesis of a series of 64 new N-heterocycles from the three nitrobutadienes 2-nitroperchloro-1,3-butadiene, 4-bromotetrachloro-2-nitro-1,3-butadiene and (Z)-1,1,4-trichloro-2,4-dinitrobuta-1,3-diene proved feasible. Their reactions with N-, O- and S-nucleophiles provide rapid access to push-pull substituted benzoxazolines, benzimidazolines, imidazolidines, thiazolidinones, pyrazoles, pyrimidines, pyridopyrimidines, benzoquinolines, isothiazoles, dihydroisoxazoles, and thiophenes with unique substitution patterns. Antibacterial activities of 64 synthesized compounds were examined. Additionally, seven compounds (thiazolidinone, nitropyrimidine, indole, pyridopyrimidine, and thiophene derivatives) exhibited a significant cytotoxicity with IC₅₀-values from 1.05 to 20.1 µM. In conclusion, it was demonstrated that polyhalonitrobutadienes have an interesting potential as structural backbones for a variety of highly functionalized, pharmaceutically active heterocycles.

Biodistribution and Anticancer Characteristics of Les-3833, A Novel 4-thiazolidinone-Based Lead Compound

Recently, we identified the promising anticancer potential of the synthetic 4-thiazolidinone-based anticancer lead compound Les-3833 which demonstrated tumor-suppressing action in vitro and in vivo. Based on the results of previous studies, the aim of this research was to investigate the cytotoxicity in vitro and the biodistribution in laboratory mice to support the biotherapeutic drug development of Les-3833. Les-3833 (2.5 mg/kg) was intravenously injected into male Balb/c mice. Measurements were performed at 5 min, 15 min, 1 h, 4 h, and 24 h time points in blood plasma, brain, liver, and kidney using high-performance liquid chromatography/tandem mass spectrometry. After the administration of Les-3833, the maximum level of this compound was observed in plasma at 2.08 min. In the brain, the mean maximum concentration of Les-3833 was 7.17 ng/mL at 5 min, while after 15 min, it was not found. In the liver, at 5 min, the maximum concentration was 1190 ng/g. At 15 min, concentration of Les-3833 in the liver decreased by 14.3%; at 6 h by 22.8%; and after 24 h by 64.7%. Its maximum concentration in kidney was 404 ng/g within 5–15 min, at 1 h it decreased by 36.1%, and after 24 h by 49.3%. Thus, Les-3833 was rapidly taken up by different organs from the bloodstream, partially metabolized in the liver, and excreted mainly through the kidneys, while in the brain, a very low concentration could be observed for only a short period of time.

Synthesis of Novel Fluorine Compounds Substituted-4-thiazolidinones Derived from Rhodanine Drug as Highly Bioactive Probes

Aim and Objective:

It is known that rhodanine drug has various biocidal activities. The aim of this work was to improve the structure of rhodanine drug via alkylation at N, S, and O- centers in addition to the introduction of fluorine atoms. The new fluorinated modified rhodanines 2-16 were evaluated as enzymatic probes for cellobiase activity produced by fungi and as CDK2 inhibitors of tumor cells.

Materials and Methods:

Novel fluorine substituted N-alkyl, S-alkyl and amino-rhodanines were obtained via Hydroxy methylation, Mannich reactions, chlorination and amination of 5-(4'-fluorophenylene)-2-thioxo-thiazolidin-4-one, and the enzymatic effects of cellobiase produced by fungi and /or CDK2 inhibition of tumor cells were evaluated.

Results:

Most of the targets were obtained in high yield and in the form of very pure crystals with characteristic colors. Only compounds 5, 8, 10, 13, and 14 exhibited a higher activity as cellobiase while compounds 2 and 5 showed a highly enzymatic effect on tumor cells. In addition, compounds 2 and 10 can be used as Olomoucine (standard referees).

Conclusion:

Various N, S and O-alkyl derivatives of fluorine-substituted rhodanines were prepared via a simple method and used as enzymatic probes for cellobiase activity produced by fungi and CDK2 inhibitors for tumor cells. The more bioactive compounds had rich fluorine atoms as p-fluorophenyl and p-fluorobenzoyl bearing N, S, O-alkyl rhodanine. The highly active compounds may be used as enzymatic materials for various biological transformations in the future.

Structures and transistor properties of extended and unsymmetrical birhodanines

Extended and unsymmetrical birhodanines, including phenyl and unsubstituted parts, are prepared and show characteristic molecular packing and n-channel transistor properties.

Phosphorylation Dynamics of JNK Signaling: Effects of Dual-Specificity Phosphatases (DUSPs) on the JNK Pathway

Protein phosphorylation affects conformational change, interaction, catalytic activity, and subcellular localization of proteins. Because the post-modification of proteins regulates diverse cellular signaling pathways, the precise control of phosphorylation states is essential for maintaining cellular homeostasis. Kinases function as phosphorylating enzymes, and phosphatases dephosphorylate their target substrates, typically in a much shorter time. The c-Jun N-terminal kinase (JNK) signaling pathway, a mitogen-activated protein kinase pathway, is regulated by a cascade of kinases and in turn regulates other physiological processes, such as cell differentiation, apoptosis, neuronal functions, and embryonic development. However, the activation of the JNK pathway is also implicated in human pathologies such as cancer, neurodegenerative diseases, and inflammatory diseases. Therefore, the proper balance between activation and inactivation of the JNK pathway needs to be tightly regulated. Dual specificity phosphatases (DUSPs) regulate the magnitude and duration of signal transduction of the JNK pathway by dephosphorylating their substrates. In this review, we will discuss the dynamics of phosphorylation/dephosphorylation, the mechanism of JNK pathway regulation by DUSPs, and the new possibilities of targeting DUSPs in JNK-related diseases elucidated in recent studies.

Synthesis, in-Vitro Cytotoxicity and Antimicrobial Evaluations of Some Novel Thiazole Based Heterocycles

Condensation of rhodanine (1) with pyrazol-3(2H)-one derivatives (2a-f) gave 5-substituted-2-thioxo-1,3-thiazolidin-4-one derivatives (3a-f). Reaction of compound (1) with 2-arylmethylidene-malononitrile (4a-d) yielded the unexpected derivatives (5a-d). The latter compounds were subjected to cyclization reactions with malononitrile under different basic conditions, hydroxylamine hydrochloride and/or thiourea to furnish the fused thiazole derivatives (6a-d) and (8-10a-d). Coupling of (1) with diazotized aromatic amines (11a-c) in pyridine afforded the arylhydrazones (12a-c). Fusion of latter compounds with malononitrile afforded the thiazolopyridazine derivatives (13a-c). The structures of the newly synthesized compounds were elucidated via spectral data and elemental analyses. The in-vitro cytotoxic activity of compounds (3a-f) against the cell line MCF-7 was evaluated. Also, the synthesized products were investigated for their antibacterial and antifungal activities against six standard organisms including the G⁺ bacteria, Staphylococcus aureus and Bacillus subtilis, G^- bacteria, Escherichia coli and Proteus vulgaris in addition to fungi, Candida albicans and Aspergillus flavus.

Synthesis and Cytotoxic Activity against K562 and MCF7 Cell Lines of SomeN-(5-Arylidene-4-oxo-2-thioxothiazolidin-3-yl)-2-((4-oxo-3-phenyl-3,4-dihydroquinazoline-2-yl)thio)acetamide Compounds

Ethyl 2-((4-oxo-3-phenyl-3,4-dihydroquinazolin-2-yl)thio)acetate (3) which was synthesized starting from anthranilic acid (1) via 2-thioxo-3-phenylquinazolin-4(3H)-one (2) reacted with hydrazine hydrate to afford 2-((4-oxo-3-phenyl-3,4-dihydroquinazolin-2-yl)thio)acetohydrazide (4). Reaction of (4) with thiocarbonyl-bis-thioglycolic acid gave a new compound nameN-(4-oxo-2-thioxothiazolidin-3-yl)-2-((4-oxo-3-phenyl-3,4-dihydroquinazolin-2-yl)thio)acetamide (5). Knoevenagel condensation of (5) with appropriate aldehydes gave fourteen (Z)-N-(5-arylidene-4-oxo-2-thioxothiazolidin-3-yl)-2-((4-oxo-3-phenyl-3,4-dihydroquinazolin-2-yl)thio)acetamide compounds (6a–o) with moderate yield. The chemical structure of the compounds was elucidated on the basis of IR,1H-NMR,13C-NMR, and HR-MS spectral data. The 5-arylidene-2-thioxothiazolidinone compounds exhibited mild-to-moderate cytotoxic activity against both K562 (chronic myelogenous leukemia) cells and MCF7 (breast cancer) cells.

Discovery of certain benzyl/phenethyl thiazolidinone-indole hybrids as potential anti-proliferative agents: Synthesis, molecular modeling and tubulin polymerization inhibition study

A series of certain benzyl/phenethyl thiazolidinone-indole hybrids were synthesized for the study of anti-proliferative activity against A549, NCI-H460 (lung cancer), MDA-MB-231 (breast cancer), HCT-29 and HCT-15 (colon cancer) cell lines by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). We found that compound G37 displayed highest cytotoxicity with IC₅₀ value of 0.92 ± 0.12 µM towards HCT-15 cancer cell line among all the synthesized compounds. Moreover, compound G37 was also tested on normal human lung epithelial cells (L132) and was found to be safe in contrast to HCT-15 cells. The lead compound G37 showed significant G2/M phase arrest in HCT-15 cells. Additionally, compound G37 significantly inhibited tubulin polymerization with IC₅₀ value of 2.92 ± 0.23 µM. Mechanistic studies such as acridine orange/ethidium bromide (AO/EB) dual staining, DAPI nuclear staining, annexinV/propidium iodide dual staining, clonogenic growth inhibition assays inferred that compound G37 induced apoptotic cell death in HCT-15 cells. Moreover, loss of mitochondrial membrane potential with elevated intracellular ROS levels was observed by compound G37. These compounds bind at the active pocket of the α/β-tubulin with higher number of stable hydrogen bonds, hydrophobic and arene-cation interactions confirmed by molecular modeling studies.

Hybridized Quinoline Derivatives as Anticancer Agents: Design, Synthesis, Biological Evaluation and Molecular Docking

Objective:

Conjugating quinolones with different bioactive pharmacophores to obtain potent anticancer active agents.

Methods:

Fused pyrazolopyrimidoquinolines 3a-d, Schiff bases 5, 6a-e, two hybridized systems: pyrazolochromenquinoline 7 and pyrazolothiazolidinquinoline 8, different substituted thiazoloquinolines 13-15 and thiazolo[3,2-a]pyridine derivatives 16a-c were synthesized. Their chemical structures were characterized through spectral and elemental analysis, cytotoxic activity on five cancer cell lines, caspase-3 activation, tubulin polymerization inhibition and cell cycle analysis were evaluated.

Results:

Four compounds 3b, 3d, 8 and 13 showed potent activity than doxorubicin on HCT116 and three compounds 3b, 3d and 8 on HEPG2. These promising derivatives showed increase in the level of caspase-3. The trifloromethylphenyl derivatives of pyrazolopyrimidoquinolines 3b and 3d showed considerable tubulin polymerization inhibitory activity. Both compounds arrested cell cycle at G2/M phase and induced apoptosis.

Conclusion:

Compounds 3b and 3d can be considered as promising anticancer active agents with 70% of colchicine activity on tubulin polymerization inhibition and represent hopeful leads that deserve further investigation and optimization.

Design and synthesis of phenylpiperazine derivatives as potent anticancer agents for prostate cancer

Novel thiourea (5a, 5b) and thiazolidinone derivatives (6a, 6b) were synthesized by hybridizing molecules starting from the compound 6-(4-phenylpiperazin-1-yl)pyridin-3-amine (4) which is known to show anticancer activity. The synthesis of the leading compound was carried out by using 1-(5-nitropyridin-2-yl)-4-phenylpiperazine (3) which was obtained by a novel method of the reaction of 2-chloro-5-nitropyridine (1) and N-phenylpiperazine (2). The structures of the compounds were confirmed using FTIR, ¹ H NMR, ¹³ C NMR, HRMS spectroscopic methods and elemental analysis. The organic molecules were tested for their anticancer activities against prostate cancer (PC) cell lines: DU 145, PC-3 and LNCaP. As the compound 5a exerted the highest cytotoxic activity, IC₅₀ concentrations of compound 5a were further investigated in terms of morphology, colony-forming ability, RNA expression, fragmented DNA and cell cycle distributions of PC cell lines. Overall data revealed that compound 5a treatment induces apoptosis and DNA fragmentation in PC cell lines and inhibits cell cycle progression resulting in the accumulation of cells in either the G1 or the S phases.

Identification of a rhodanine derivative BML-260 as a potent stimulator of UCP1 expression

Identification of proper agents to increase or activate UCP1⁺ cells in adipose tissues remains a potent therapeutic strategy to combat obesity. Screening systems for UCP1 activators have been previously established and allow for unbiased discovery of effective compound(s).

Methods: A previously established Ucp1-2A-GFP reporter system was applied to a chemical library containing 33 phosphatase inhibitors. Compounds that can significantly activate UCP1 expression were further tested in vivo in mouse adipose tissues. Possible underlying mechanism was explored via RNA profiling, CMAP analysis, CRISPR targeting as well as inhibitor treatments.

Results: We identified BML-260, a known potent inhibitor of the dual-specific phosphatase JSP-1, that significantly increased UCP1 expression in both brown and white adipocytes. BML-260 treatment also activated oxidative phosphorylation genes, increased mitochondrial activity as well as heat generation in vitro and in vivo. Mechanistic studies revealed that effect of BML-260 on adipocytes was partly through activated CREB, STAT3 and PPAR signaling pathways, and was unexpectedly JSP-1 independent.

Conclusion: The rhodanine derivate BML-260 was previously identified to be a JSP-1 inhibitor, and thus was proposed to treat inflammatory and proliferative disorders associated with dysfunctional JNK signaling. This work provides evidences that BML-260 can also exert a JSP-1-independent effect in activating UCP1 and thermogenesis in adipocytes, and be potentially applied to treat obesity.

Synthesis and antibacterial activity of new (2,4-dioxothiazolidin-5-yl/ylidene)acetic acid derivatives with thiazolidine-2,4-dione, rhodanine and 2-thiohydantoin moieties

A series of new (2,4-dioxothiazolidin-5-yl/ylidene)acetic acid derivatives with thiazolidine-2,4-dione, rhodanine and 2-thiohydantoin moiety (28–65) were synthesized by the reaction of (2,4-dioxothiazolidin-5-yl/ylidene)acetic acid chlorides with 5-(hydroxybenzylidene) thiazolidine-2,4-dione, rhodanine and 2-thiohydantoin derivatives. Obtained compounds (28–65) were tested on reference strains of Gram-positive bacteria and ones of the Gram-negative bacteria. The antibacterial activity of target compounds was determined by broth microdilution method. These derivatives showed antibacterial activity generally against Gram-positive bacterial strains. Most active compounds possess MIC = 3.91 mg/L. Our results suggest that presence of electron-withdrawing substituent at phenyl ring is favorable while geometry of molecule does not play important role in antibacterial response. It was confirmed the lack of direct influence of substitution pattern at phenyl ring on antibacterial activity of closely related compounds of series 1–3. The antibacterial activity of some compounds was similar or higher than the activity of commonly used reference drugs such as oxacillin and cefuroxime.

Atropisomerism in 3-arylthiazolidine-2-thiones. A combined dynamic NMR and dynamic HPLC study

Sterically hindered 3-arylthiazolidine-2-thiones were prepared by a solvent-free reaction with arylisothiocyanates and 1,4-dithiane-2,5-diol. Atropisomerism was observed in two compounds (3 and 4, aryl = 1-naphthyl and 2-methylnaphth-1-yl), whose rotational energy barriers were measured using dynamic NMR and dynamic HPLC. The experimental analyses were supported by DFT calculations. Thermally stable atropisomers were obtained by dehydration of compounds 3 and 4 and the absolute configuration of the atropisomers of compound 6 was determined by theoretical simulation of the ECD and VCD spectra.

Design and synthesis of novel quinacrine-[1,3]-thiazinan-4-one hybrids for their anti-breast cancer activity

In an attempt to develop effective and safe anticancer agents, we designed, synthesized and examined 23 novel quinacrine (QC) derivatives by combining the 9-aminoacridine scaffold and the [1,3]thiazinan-4-ones group. Most of these hybrids showed strong anticancer activities, among which 3-(3-(6-chloro-2-methoxyacridin-9-ylamino)propyl)-2-(thiophen-2-yl)-1,3-thiazinan-4-one (25; VR151) effectively killed many different cancer cell types, including eight breast cancer cell lines with different genetic background, two prostate cancer and two lung cancer cell lines. In contrast, compound 25 is less effective against non-cancer cells, suggesting it may be less toxic to humans. Our data showed that cancer cells are arrested in S phase for a prolonged period due to the down-regulation of DNA replication, leading to eventual cell death. We have also shown that the S phase arrest may be resulted by the down-regulation of cyclin A coupled with the continued up-regulation of cyclin E, which coincide with the down-regulation of mTor-S6K and mTor-4EBP1 pathways.

Design, synthesis and biological evaluation of novel pyridine-thiazolidinone derivatives as anticancer agents: Targeting human carbonic anhydrase IX

In order to obtain novel Human carbonic anhydrase IX (CAIX) inhibitors, a series of pyridine-thiazolidinone derivatives was synthesized and characterized by various spectroscopic techniques. The binding affinity of the compounds was measured by fluorescence binding studies and enzyme inhibition activity using esterase assay of CAIX. It was observed that compound 8 and 11 significantly inhibit the CAIX activity with the IC₅₀ value, 1.61 μM and 1.84 μM, respectively. The binding-affinity of compound 8 and 11 for CAIX was significantly high with their K_D values 11.21 μM and 2.32 μM, respectively. Docking studies revealed that compound 8 and 11 efficiently binds in the active site cavity of CA IX by forming sufficient numbers of H-bonds and van der Waals interactions with active side residues. All the compounds were further screened in vitro for anticancer activity and found that compound 8 and 11 exhibit considerable anticancer activity against MCF-7 and HepG-2 cell lines. All these findings suggest that compound 8 and 11 may be further exploited as a novel pharmacophore model for the development of anticancer agents.