Development of chromone-thiazolidine-2,4-dione Knoevenagel conjugates as apoptosis inducing agents.

Overexpression of Bcl-2 protein is a predominant hallmark of disturbed apoptotic pathway in most of the cancers. Herein, chromone-linked thiazolidinediones were designed and synthesized to target Bcl-2 for regulating anti-apoptotic proteins. The study on in vitro cancer cell lines revealed the presence of compounds 8a, 8k, 8l, and 8n, which were found to have good to moderate anti-proliferative activity (with an IC50 concentration less than 10 µM). Among them, 8l depicted the highest cytotoxicity on the A549 cell line with an IC50 of 6.1 ± 0.02 µM. Aberrantly, the compounds displayed less toxicity towards human embryonic kidney HEK cells underlining its selectivity. The DCFDA study revealed a gradual increase in the ROS generation of 8l, followed by its quantification by flow analysis. Similarly, the studies including DAPI, AO/EtBr and Annexin-V binding clearly elucidated the DNA damage, membrane integrity prospects, and insights for early and late apoptotic phases. Markedly, the Bcl-2-FITC anti-body study revealed that compound 8l reduced the expression of anti-apoptotic proteins by 79.1 % compared to the control at 9 µM concentration. In addition, the molecular docking study provided the impending scope of these hybrids, showing promising interaction with the Mcl-1 target (member of the Bcl-2 family) with comparable binding affinities.

Discovery and development of thiazolidine-2,4-dione derivatives as Bcl-2/Mcl-1 dual inhibitors.

Increasing the levels of antiapoptotic Bcl-2 proteins is an important way that cancer cells utilize to get out of apoptosis, underscoring their significance as promising targets for anticancer therapies. Lately, a primary compound 1 bearing thiazolidine-2,4-dione was discovered to exhibit comparable Mcl-1 inhibitory activity in comparison to WL-276. Herein, thirty-nine thiazolidine-2,4-dione analogs were yielded through incorporating different biphenyl moieties (R1), amino acid side chains (R2) and sulfonamides (R3) on 1. The findings indicated that certain compounds exhibited favorable inhibitory effects against Bcl-2/Mcl-1, while demonstrating limited or negligible binding affinity towards Bcl-xL. In particular, compounds 16 and 20 exhibited greater Bcl-2/Mcl-1 inhibition compared to AT-101, WL-276 and 1. Moreover, they demonstrated notable antiproliferative effects and significantly induced apoptosis in U937 cells. The western blot and co-immunoprecipitation assays confirmed that 20 could induce alterations in the expression of apoptosis-associated proteins to result in apoptosis through on-target Bcl-2 and Mcl-1 inhibition. In addition, 20 exhibited favorable stability profiles in both rat plasma and rat liver microsomes. In total, 20 could be used as a promising compound to discover Bcl-2/Mcl-1 dual inhibitors with favorable therapeutic properties.

Synthesis, Antimicrobial Evaluation, DFT, in Silico-Docking, and ADMET Investigations of Novel Chromene-Based 2,4-Thiazolidinediones.

Three series of thiazolidinedione (TZD) derivatives (5a-f, 7a-f, and 9a-f) were prepared efficiently. Afterward, the synthesized candidates' antibacterial efficacy against both gram-positive and gram-negative bacteria was assessed. Compounds 7c, 7d, and 7f had values comparable to that of ampicillin, a reference antibiotic, whereas compounds 5c, 5d, and 7e exhibited the greatest values (23.0±1.0, 27.7±0.6, and 20.0±1.0, respectively) against gram-positive bacteria (Staphylococcus aureus). The optimal structure of the produced molecules was determined by DFT computing. To assess the binding energy and elucidate the interaction between the potential candidates and different proteins, in silico docking is employed. ADMET analysis to assess the synthesized compounds' toxicity, metabolism, excretion, distribution, and absorption.

Design, Synthesis, and Characterization of Novel Thiazolidine-2,4-Dione-Acridine Hybrids as Antitumor Agents.

This study focuses on the synthesis and structural characterization of new compounds that integrate thiazolidine-2,4-dione, acridine moiety, and an acetamide linker, aiming to leverage the synergistic effects of these pharmacophores for enhanced therapeutic potential. The newly designed molecules were efficiently synthesized through a multi-step process and subsequently transformed into their hydrochloride salts. Comprehensive spectroscopic techniques, including nuclear magnetic resonance (NMR), high-resolution mass spectrometry (HRMS), infrared (IR) spectroscopy, and elemental analysis, were employed to determine the molecular structures of the synthesized compounds. Biological evaluations were conducted to assess the therapeutic potential of the new compounds. The influence of these derivatives on the metabolic activity of various cancer cell lines was assessed, with IC50 values determined via MTT assays. An in-depth analysis of the structure-activity relationship (SAR) revealed intriguing insights into their cytotoxic profiles. Compounds with electron-withdrawing groups generally exhibited lower IC50 values, indicating higher potency. The presence of the methoxy group at the linking phenyl ring modulated both the potency and selectivity of the compounds. The variation in the acridine core at the nitrogen atom of the thiazolidine-2,4-dione core significantly affects the activity against cancer cell lines, with the acridin-9-yl substituent enhancing the compounds' antiproliferative activity. Furthermore, compounds in their hydrochloride salt forms demonstrated better activity against cancer cell lines compared to their free base forms. Compounds 12c·2HCl (IC50 = 5.4 ± 2.4 µM), 13d (IC50 = 4.9 ± 2.9 µM), and 12f·2HCl (IC50 = 4.98 ± 2.9 µM) demonstrated excellent activity against the HCT116 cancer cell line, and compound 7d·2HCl (IC50 = 4.55 ± 0.35 µM) demonstrated excellent activity against the HeLa cancer cell line. Notably, only a few tested compounds, including 7e·2HCl (IC50 = 11.00 ± 2.2 µM), 7f (IC50 = 11.54 ± 2.06 µM), and 7f·2HCl (IC50 = 9.82 ± 1.92 µM), showed activity against pancreatic PATU cells. This type of cancer has a very high mortality due to asymptomatic early stages, the occurrence of metastases, and frequent resistance to chemotherapy. Four derivatives, namely, 7e·2HCl, 12d·2HCl, 13c·HCl, and 13d, were tested for their interaction properties with BSA using fluorescence spectroscopic studies. The values for the quenching constant (Ksv) ranged from 9.59 × 104 to 10.74 × 104 M-1, indicating a good affinity to the BSA protein.

BCL6 BTB-specific inhibitor reversely represses T-cell activation, Tfh cells differentiation, and germinal center reaction in vivo.

Inhibition of the BCL6 BTB domain results in killing Diffuse Large B-cell Lymphoma (DLBL) cells, reducing the T-cell dependent germinal center (GC) reaction in mice, and reversing GC hyperplasia in nonhuman primates. The available BCL6 BTB-specific inhibitors are poorly water soluble, thus, limiting their absorption in vivo and our understanding of therapeutic strategy targeting GC. We synthesized a prodrug (AP-4-287) from a potent BCL6 BTB inhibitor (FX1) with improved aqueous solubility and pharmacokinetics (PK) in mice. We also evaluated its in vivo biological activity on humoral immune responses using the sheep red blood cells (SRBC)-vaccination mouse model. AP-4-287 had a significant higher aqueous solubility and was readily converted to FX1 in vivo after intraperitoneally (i.p.) administration, but a shorter half-life in vivo. Importantly, AP-4-287 treatment led to a reversible effect on (1) the reduction in the frequency of splenic Ki67+ CD4+ T cells, Tfh cells, and GC B cells; (2) lower GC formation following vaccination; and (3) a decrease in the titers of antigen-specific IgG and IgM antibodies. Our study advances the preclinical development of drug targeting BCL6 BTB domain for the treatment of diseases that are associated with abnormal BCL6 elevation.

Discovery of 2,4-thiazolidinedione-tethered coumarins as novel selective inhibitors for carbonic anhydrase IX and XII isoforms.

Different 2,4-thiazolidinedione-tethered coumarins 5a-b, 10a-n and 11a-d were synthesised and evaluated for their inhibitory action against the cancer-associated hCAs IX and XII, as well as the physiologically dominant hCAs I and II to explore their selectivity. Un-substituted phenyl-bearing coumarins 10a, 10 h, and 2-thienyl/furyl-bearing coumarins 11a-c exhibited the best hCA IX (KIs between 0.48 and 0.93 µM) and hCA XII (KIs between 0.44 and 1.1 µM) inhibitory actions. Interestingly, none of the coumarins had any inhibitory effect on the off-target hCA I and II isoforms. The sub-micromolar compounds from the biochemical assay, coumarins 10a, 10 h and 11a-c, were assessed in an in vitro antiproliferative assay, and then the most potent antiproliferative agent 11a was tested to explore its impact on the cell cycle phases and apoptosis in MCF-7 breast cancer cells to provide more insights into the anticancer activity of these compounds.

Thiazolidinedione Derivatives: In Silico, In Vitro, In Vivo, Antioxidant and Anti-Diabetic Evaluation.

This work aimed to synthesize a new antihyperglycemic thiazolidinedione based on the spectral data. The DFT\B3LYP\6-311G** level of theory was used to investigate the frontier molecular orbitals (FMOs), chemical reactivity and map the molecular electrostatic potentials (MEPs) to explain how the synthesized compounds interacted with the receptor. The molecular docking simulations into the active sites of PPAR-γ and α-amylase were performed. The in vitro potency of these compounds via α-amylase and radical scavenging were evaluated. The data revealed that compounds (4-6) have higher potency than the reference drugs. The anti-diabetic and anti-hyperlipidemic activities for thiazolidine-2,4-dione have been investigated in vivo using the alloxan-induced diabetic rat model along with the 30 days of treatment protocol. The investigated compounds didn't show obvious reduction of blood glucose during pre-treatments compared to diabetic control, while after 30 days of treatments, the blood glucose level was lower than that of the diabetic control. Compounds (4-7) were able to regulate hyperlipidemia levels (cholesterol, triglyceride, high-density lipoproteins and low- and very-low-density lipoproteins) to nearly normal value at the 30th day.

Synthesis and structure-activity relationship studies of 2,4-thiazolidinediones and analogous heterocycles as inhibitors of dihydrodipicolinate synthase.

Dihydrodipicolinate synthase (DHDPS), responsible for the first committed step of the diaminopimelate pathway for lysine biosynthesis, has become an attractive target for the development of new antibacterial and herbicidal agents. Herein, we report the discovery and exploration of the first inhibitors of E. coli DHDPS which have been identified from screening lead and are not based on substrates from the lysine biosynthesis pathway. Over 50 thiazolidinediones and related analogues have been prepared in order to thoroughly evaluate the structure-activity relationships against this enzyme of significant interest.

Design, synthesis and bioactivity evaluation of thiazolidinedione derivatives as partial agonists targeting PPARγ.

Thiazolidinedione (TZD) is a novel peroxides proliferator activated receptor γ (PPARγ) agonist with many side effects. Herein, we developed a series of novel TZD analogues as partial agonists targeting PPARγ. The study of anti-hyperglycemic activity and anti-inflammatory activity enabled us to identify a novel compound, 4 g, which quickly recover the blood glucose of mice at the concentration of 100 mg/kg, and show similar anti-inflammatory activity to ibuprofen at the concentration of 20 mg/kg. The competitive binding assay confirmed direct binding of 4 g to the LBD of PPARγ with IC50 being 1790 nM, and dose-dependently increased the transcriptional activity of PPARγ. Besides, through computer-aided drug design software simulation docking, it was found that compound 4 g showed the best binding ability to target protein PPARγ. Furthermore, because of the introduction of benzene containing group at N3 position, the stability of H12 in the active pocket is reduced and the stability of H3 and ß-fold is increased, showing the characteristics of some PPARγ agonists, based on the docking model analysis. Together, these results suggest that 4 g is a promising PPARγ agonist that deserves further investigation.

Design, synthesis and anti-influenza virus activity of furan-substituted spirothiazolidinones.

A new series of N-(3-oxo-1-thia-4-azaspiro[4.5]decan-4-yl)carboxamides have been designed, synthesized and evaluated as antiviral agents. The compounds were prepared by condensation of 2-methylfuran-3-carbohydrazide, appropriate carbonyl compounds and sulfanyl acids. The new molecules were characterized by IR, 1H NMR, 13C NMR, mass spectrometry and elemental analysis. Six analogues proved to be active against influenza A/H3N2 virus, the two most protent analogues, 3c and 3d, having an EC50 value of about 1 µM. These findings help to define the SAR of spirothiazolidinone-based inhibitors of the influenza virus membrane fusion process.

Design, synthesis and biological evaluation of selective hybrid coumarin-thiazolidinedione aldose reductase-II inhibitors as potential antidiabetics.

Thiazolidinediones (TZD), benzopyrans are the proven scaffolds for inhibiting Aldose reductase (ALR2) activity and their structural confluence with the retention of necessary fragments helped in designing a series of hybrid compounds 2-(5-cycloalkylidene-2,4-dioxothiazolidin-3-yl)-N-(2-oxo-2H-chromen-3-yl)acetamide (10a-n) for better ALR2 inhibition. The compounds were synthesized by treating substituted 3-(N-bromoacetyl amino)coumarins (9a-d) with potassium salt of 5-cyclo alkylidene-1,3-thiazolidine-2,4-diones (4a-d). The inhibition activity against ALR2 with IC50 values range from 0.012 ± 0.001 to 0.056 ± 0.007 µM. N-[(6-Bromo-3-coumarinyl)-2-(5-cyclopentylidene-2,4-dioxothiazolidin-3-yl)] acetamide (10c) with cyclopentylidene group on one end and the 6-bromo group on the other end showed better inhibitory property (IC50 = 0.012 µM) and selectivity index (324.166) against the ALR2, a forty fold superiority over sorbinil, a better molecule over epalrestat and rest of the analogues exhibited a far superior response over sorbinil and slightly better as compared with epalrestat. It was further confirmed by the insilico studies that compound 10c showed best inhibition activity among the synthesized compounds with a high selectivity index against the ALR2. In invivo experiments, supplementation of compound 10c to STZ induced rats delayed the progression of cataract in a dose-dependent manner warranting its further development as a potential agent to treat thediabetic secondary complications especially cataract.

Thiazolidinone-linked1,2,3-triazoles with monoterpenic skeleton as new potential anticancer agents: Design, synthesis and molecular docking studies.

A novel series of 1,2,3-triazole-thiazolidinone-carvone hybrid compounds has been designed and synthesized using the copper-catalyzed Huisgen azide-alkyne 1,3-dipolar cycloaddition (CuAAC) process based on (R)-Carvone-O-propargylated 5-hydroxybenzylidene-thiazolidin-4-one derivative as starting material. All compounds were characterized and identified based on their NMR and HRMS spectroscopic data. HMBC correlations confirm that under the CuAAC reaction conditions, only the 1,4-disubstituted triazole regioisomers were formed. The targeted 1,2,3-triazole-thiazolidinone-carvone hybrids and their precursors were evaluated for their cytotoxic activity against four human cancer cell lines, including fibrosarcoma (HT-1080), lung carcinoma (A-549), and breast carcinoma (MCF-7 and MDA-MB-231). The obtained data showed that most of these compounds have moderate anti-proliferative activity with IC50 values between 15.04 ± 0.71 and 42.22 ± 1.20 µM. The mechanism of action of the most active compounds 14e and 14f suggested that they induce apoptosis through caspase-3/7 activation, and the compound 14e elicited S-phase arrest, while compound 14f evoked G2/M phase blockade. The molecular docking confirmed that compounds 14e and 14f were nicely bonded with caspace-3 leading up to stable protein-ligand complexes.

Double-edged Swords: Diaryl pyrazoline thiazolidinediones synchronously targeting cancer epigenetics and angiogenesis.

In the present study, two novel series of compounds incorporating naphthyl and pyridyl linker were synthesized and biological assays revealed 5-((6-(2-(5-(2-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl)-2-oxoethoxy) naphthalene-2-yl)methylene)thiazolidine-2,4-dione (14b) as the most potent dual inhibitors of vascular endothelial growth factors receptor-2 (VEGFR-2) and histone deacetylase 4 (HDAC4). Compounds 13b, 14b, 17f, and 21f were found to stabilize HDAC4; where, pyridyl linker swords were endowed with higher stabilization effects than naphthyl linker. Also, 13b and 14b showed best inhibitory activity on VEGFR-2 as compared to others. Compound 14b was most potent as evident by in-vitro and in-vivo biological assessments. It displayed anti-angiogenic potential by inhibiting endothelial cell proliferation, migration, tube formation and also suppressed new capillary formation in the growing chick chorioallantoic membranes (CAMs). It showed selectivity and potency towards HDAC4 as compared to other HDAC isoforms. Compound 14b (25 mg/kg, i.p.) also indicated exceptional antitumor efficacy on in-vivo animal xenograft model of human colorectal adenocarcinoma (HT-29). The mechanism of action of 14b was also confirmed by western blot.

Synthesis and biological evaluation of thiazolidinedione derivatives with high ligand efficiency to P. aeruginosa PhzS.

The thiazolidinone ring is found in compounds that have widespan biology activity and there is mechanism-based evidence that compounds bearing this moiety inhibit P. aeruginosa PhzS (PaPzhS), a key enzyme in the biosynthesis of the virulence factor named pyocyanin. Ten novel thiazolidinone derivatives were synthesised and screened against PaPhzS, using two orthogonal assays. The biological results provided by these and 28 other compounds, whose synthesis had been described, suggest that the dihydroquinazoline ring, found in the previous hit (A- Kd = 18 µM and LE = 0.20), is not required for PaPzhS inhibition, but unsubstituted nitrogen at the thiazolidinone ring is. The molecular simplification approach, pursued in this work, afforded an optimised lead compound (13- 5-(2,4-dimethoxyphenyl)thiazolidine-2,4-dione) with 10-fold improvement in affinity (Kd= 1.68 µM) and more than 100% increase in LE (0.45), which follows the same inhibition mode as the original hit compound (competitive to NADH).Executive summaryPhzS is a key enzyme in the pyocyanin biosynthesis pathway in P. aeruginosa.Orthogonal assays (TSA and FITC) show that fragment-like thiazolidinedione derivatives bind to PaPhzS with one-digit micromolar affinity.Fragment-like thiazolidinedione derivatives bind to the cofactor (NADH) binding site in PaPhzS.The molecular simplification optimised the ligand efficiency and affinity of the lead compound.

Design, synthesis, and molecular docking studies of thiazolidinediones as PPAR-γ agonists and thymidylate synthase inhibitors.

New thiazolidine-2,4-dione hybrids were designed and synthesized as potential peroxisome proliferator-activated receptor (PPAR)-γ agonists and thymidylate synthase inhibitors. All the synthesized compounds follow Lipinski's and Veber's rules and possess the desired pharmacokinetics properties. The PPAR-γ transactivation results displayed that compounds 12 (78.9%) and 11 (73.4%) were the most active compounds and they increased PPAR-γ gene expression by 2.2- and 2.4-fold, respectively. Compounds 12, 11, and 8 showed promising cytotoxicity, with IC50 values ranging from 1.4 to 4.5 µM against MCF-7 cells and from 1.8 to 8.4 µM against HCT-116 cells. Compounds 11 and 12 also inhibited thymidylate synthase with IC50 values of 5.1 and 3.2 µM, respectively, confirming their mode of action as thymidylate synthase inhibitors. Finally, molecular docking studies supported the in vitro biological activity results.

Design, synthesis, docking, ADMET profile, and anticancer evaluations of novel thiazolidine-2,4-dione derivatives as VEGFR-2 inhibitors.

The anticancer activity of novel thiazolidine-2,4-diones was evaluated against HepG2, HCT-116, and MCF-7 cells. Among the tested cancer cell lines, HCT-116 was the most sensitive one to the cytotoxic effect of the new derivatives. In particular, compounds 18, 11, and 10 were found to be the most potent derivatives among all the tested compounds against the HepG2, HCT-116, and MCF-7 cancer cell lines, with IC50 values ranging from 38.76 to 53.99 µM. The most active antiproliferative derivatives (7-14 and 15-19) were subjected to further biological studies to evaluate their inhibitory potentials against VEGFR-2. The tested compounds displayed a good-to-medium inhibitory activity, with IC50 values ranging from 0.26 to 0.72 µM. Among them, compounds 18, 11, and 10 potently inhibited VEGFR-2 at IC50 values in the range of 0.26-0.29 µM, which are nearly three times that of the sorafenib IC50 value (0.10 µM). Although our derivatives showed lower activities than the reference drug, they could be useful as a template for future design, optimization, adaptation, and investigation to produce more potent and selective VEGFR-2 inhibitors with higher anticancer analogs. The ADMET profile showed that compounds 18, 11, and 10 do not violate any of Lipinski's rules and have a comparable intestinal absorptivity in humans. Also, the new derivatives could not inhibit cytochrome P3A4. Unlike sorafenib and doxorubicin, compounds 18, 11, and 10 are expected to have prolonged dosing intervals. Moreover, compounds 10 and 18 displayed a wide therapeutic index and higher selectivity against cancer cells as compared with their cytotoxicity against normal cells.

Design, synthesis, molecular docking, anticancer evaluations, and in silico pharmacokinetic studies of novel 5-[(4-chloro/2,4-dichloro)benzylidene]thiazolidine-2,4-dione derivatives as VEGFR-2 inhibitors.

The anticancer activity of novel thiazolidine-2,4-diones was evaluated against HepG2, HCT-116, and MCF-7 cells. MCF-7 was the most sensitive cell line to the cytotoxicity of the new derivatives. In particular, compounds 18, 12, 17, and 16 were found to be the most potent derivatives over all the tested compounds against the cancer cell lines HepG2, HCT116, and MCF-7, with IC50 = 9.16 ± 0.9, 8.98 ± 0.7, 5.49 ± 0.5 µM; 9.19 ± 0.5, 8.40 ± 0.7, 6.10 ± 0.4 µM; 10.78 ± 1.2, 8.87 ± 1.5, 7.08 ± 1.6 µM; and 10.87 ± 0.8, 9.05 ± 0.7, 7.32 ± 0.4 µM, respectively. Compounds 18 and 12 have nearly the same activities as sorafenib (IC50 = 9.18 ± 0.6, 5.47 ± 0.3, and 7.26 ± 0.3 µM, respectively), against HepG2 cells, but slightly lower activity against HCT116 cells and slightly higher activity against the MCF-7 cancer cell line. Also, these compounds displayed lower activities than doxorubicin against HepG2 and HCT-116 cells but higher activity against MCF-7 cells (IC50 = 7.94 ± 0.6, 8.07 ± 0.8, and 6.75 ± 0.4 µM, respectively). In contrast, compounds 17 and 16 exhibited lower activities than sorafenib against HepG2 and HCT116 cells, but nearly equipotent activity against the MCF-7 cancer cell line. Also, these compounds displayed lower activities than doxorubicin against the three cell lines. All the synthesized derivatives 7-18 were evaluated for their inhibitory activities against VEGFR-2. The tested compounds displayed high to medium inhibitory activity, with IC50 values ranging from 0.17 ± 0.02 to 0.27 ± 0.03 µM. Compounds 18, 12, 17, and 16 potently inhibited VEGFR-2 at IC50 values of 0.17 ± 0.02, 0.17 ± 0.02, 0.18 ± 0.02, and 0.18 ± 0.02 µM, respectively, which are nearly more than half of that of the IC50 value for sorafenib (0.10 ± 0.02 µM).

Discovery of Small-Molecule Modulators of Protein-RNA Interactions by Fluorescence Intensity-Based Binding Assay.

Protein-RNA interactions mediate various cellular processes, the dysregulation of which has been associated with a list of diseases. Thus, novel experimental tools for monitoring protein-RNA interactions are highly desirable to identify new chemical modulators of these therapeutic targets. In this study, we constructed simple fluorescence intensity-based protein-RNA binding assays by testing multiple environment-sensitive organic fluorophores. We selected the oncogenic interaction between Lin28 and the let-7 microRNA and the important immunomodulatory Roquin-Tnf CDE interaction as representative targets. We adapted this assay to high-throughput screening for the identification of pyrazolyl thiazolidinedione-type molecules as potent small-molecule inhibitors of protein-microRNA interactions. We clearly showed the structure-activity relationships of this new class of Lin28-let-7 interaction inhibitors, and confirmed that cellular mature let-7 microRNAs and their target genes could be modulated upon treatment with the pyrazolyl thiazolidinedione-type inhibitor. We expect that our simple and adaptable screening approach can be applied for the development of various assay systems aimed at the identification of bioactive small molecules targeting protein-RNA interactions.

Benzylidene thiazolidinediones: Synthesis, in vitro investigations of antiproliferative mechanisms and in vivo efficacy determination in combination with Imatinib.

Thiazolidinedione (TZD) has been an interesting scaffold due to its proven antidiabetic activity and encouraging findings in anticancer drug discovery. We synthesised benzylidene thiazolidinedione derivatives which exhibited excellent antiproliferative effects in chronic myeloid leukemic cells K562 and the most active compounds 3t and 3x had GI50 value of 0.9 and 0.23 µM respectively. Both the compound was found to arrest the growth of K562 cells in G0/G1 phase in a time and dose dependent manner. Further, western blot analysis revealed that 3t and 3x could also inhibit the expression of cell proliferation markers, PCNA and Cyclin D1 and compound 3x up-regulated apoptosis markers, cleaved PARP1 and activated caspase 3, which could be a possible mechanism for the excellent antiproliferative effects exhibited by these compounds. In vitro combination studies of 3t and 3x with Imatinib found to potentiate the antitumor effects of Imatinib. Further in vivo efficacy in K562 xenografts, of 3t and 3x alone and in combination with Imatinib was found to be promising and far better than control group and combination treatment was found to be more effective as compared to only Imatinib treated or test compound treated animals. Thus, our findings suggest that these compounds are promising antitumor agents and could help to enhance the anticancer effects of Imatinib and other tyrosine kinase inhibitors, when used in combination.

Design, synthesis, molecular docking and anticancer evaluations of 5-benzylidenethiazolidine-2,4-dione derivatives targeting VEGFR-2 enzyme.

Novel series of 5-benzylidenethiazolidine-2,4-dione derivatives 4a-c-8a-f were designed, synthesized and evaluated for anticancer activity against HepG2, HCT-116 and MCF-7 cell lines. MCF-7 was the most sensitive cell line to the influence of the new derivatives. In particular, compound 8f was found to be the most potent derivative overall the tested compounds against the three HepG2, HCT116 and MCF-7 cancer cell lines with IC50 = 11.19 ± 0.8, 8.99 ± 0.7 and 7.10 ± 0.4 µM respectively. Compound 8f exhibited lower activity than sorafenib, (IC50 = 9.18 ± 0.6, 8.37 ± 0.7 and 5.10 ± 0.4 µM respectively), against HepG2 and HCT116 but exhibited nearly the same activity against MCF-7 cancer cell lines respectively. Also, this compound displayed lower activity than doxorubicin, (IC50 = 7.94 ± 0.6, 8.07 ± 0.8 and 6.75 ± 0.4 µM respectively), against HepG2 and HCT116 but nearly the same activity against MCF-7cell lines respectively. The most active derivatives 6c,d,f,g and 8a-f were evaluated for their inhibitory activities against VEGFR-2. The elongation of the structures to have distal moieties enhanced anticancer and VEGFR-2 inhibitory activities as in compounds 8a-f. Among them, compounds 8f was found to be the most potent derivative that inhibited VEGFR-2 at IC50 value of 0.22 ± 0.02 µM, which is nearly the half as that of sorafenib IC50 value (0.10 ± 0.02 µM). Furthermore, molecular design was performed to investigate their binding mode and affinities towards VEGFR-2 receptor. The data obtained from docking studies were highly correlated with that obtained from the biological screening.