Synthesis and anticancer activity evaluation of 4-thiazolidinones containing benzothiazole moiety

Allyl rhodanine azo dye derivatives: Potential antimicrobials target d-alanyl carrier protein ligase and nucleoside diphosphate kinase

3-Allyl-5-(4-arylazo)-2-thioxothiazolidine-4-one (HL_n ) ligands (where n = 1 to 3) were hypothesized to have antimicrobial activities mediated through inhibition of new antimicrobial targets. The ligands (HL_n ) were synthesized and characterized by infrared (IR) and ¹ H nuclear magnetic resonance (¹ H NMR) spectra. The ligands (HL_n ) were in silico screened to their potential inhibition to models of d-alanyl carrier protein ligase (DltA) (from Bacillus cereus, PDB code 3FCE) and nucleoside diphosphate kinase (NDK) (from Staphylococcus aureus; PDB code 3Q8U). HL₃ ligand has the best energy and mode of binding to both NDK and DltA, even though its binding to DltA was stronger than that to NDK. In antimicrobial activity of HL₃ ligand, morphological and cytological changes in HL₃ -treated bacteria agreed with the in silico results. The HL₃ ligand showed significant antimicrobial activity against B. cereus, S. aureus, and Fusarium oxysporium. The HL₃ -treated bacterial cells appeared malformed and incompletely separated. Its cell walls appeared electron-lucent and ruptured. They contained more mesosomes than normal cells. It was found that the HL₃ ligand represented as a bactericide against B. cereus and S. aureusby blocking target DltA, and may target NDK.

A diversity-oriented novel regioselective synthesis of sulfonamide–thiazolidinone hybrids

A regioselective multicomponent approach to sulfonamide–thiazolidinone hybrids has been developed.

Design and synthesis of benzothiazole/thiophene-4H-chromene hybrids

A library of 4H-chromene derivatives with heterocyclic substituent's at the 3 and 4-positions was synthesized in a convenient DBU catalysed three component synthesis between salicylaldehyde, acetonitrile derivatives and thiazolidinedione to afford 2-amino-3-benzothiazole-4-heterocycle-4H-chromenes and 2-amino-3-thiophenoyl-4-heterocycle-4H-chromenes derivatives in ethanol and a mixture of ethanol and water (1 : 1) at room temperature. The significance of this protocol is the feasibility of incorporating substituents simultaneously at the 3 and 4 positions of 4H-chromenes in an efficient three component reaction.

Synthesis and evaluation of thiazolidinone-pyrazole conjugates as anticancer and antimicrobial agents

AIM

To synthesize a series of new thiazolidinone-pyrazole hybrids (5a-o) and assess their anticancer (in vitro and in vivo) and antimicrobial activities.

RESULTS

The compounds 5h (against Ehrlich ascites carcinoma cells), 5e and 5i (against the human breast cancer [MDA-MB231] cell line) exhibited potent anticancer activity. All the compounds except 5g and 5e found to be less toxic for the human dermal fibroblast cells. The effective interactions of the compounds in silico with MDM2 exemplified their inhibitory potency. The derivatives also showed moderate antimicrobial activity.

CONCLUSION

The halogen atoms on various positions of the N-arylamino ring played an advantageous role in elevating the potency of the molecules. Thus, these conjugates could be used as a lead for further optimization to achieve promising therapeutics.

Baker’s yeast catalyzed one-pot synthesis of bioactive 2-[benzylidene(or pyrazol-4-ylmethylene)hydrazono]-1,3-thiazolidin-4-one-5-yl-acetic acids

An efficient and simple one-pot protocol has been developed for synthesis of substituted derivatives of 2-hydrazono-4-thiazolidinone-5-acetic acids 4a–j and 6a–g by cyclocondensation of aryl/pyrazolyl aldehyde, thiosemicarbazide and maleic anhydride in acetonitrile in the presence of readily available whole cell biocatalyst, baker’s yeast (Saccharomyces cerevisiae). The reaction is enhanced by ultrasonication.

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.

Synthesis of N,S-Heterocycles and Dithiocarbamates by the Reaction of Dithiocarbamic Acids and S-Alkyl Dithiocarbamates with Nitroepoxides

A facile and efficient procedure for the synthesis of substituted thiazole-2(3H)-thiones and thiazolidine-2-thiones by the reaction of primary amines, carbon disulfide, and nitroepoxides is described. By using secondary amines in this protocol, the corresponding dithiocarbamate-substituted phenyl-2-propanones were prepared in excellent yields. In addition, substituted thiazoles and 1-(alkylthio)-1-phenylpropan-2-ones were prepared in reactions of S-alkyl dithiocarbamates and nitroepoxides.

5-Ene-4-thiazolidinones - An efficient tool in medicinal chemistry

The presented review is an attempt to summarize a huge volume of data on 5-ene-4-thiazolidinones being a widely studied class of small molecules used in modern organic and medicinal chemistry. The manuscript covers approaches to the synthesis of 5-ene-4-thiazolidinone derivatives: modification of the C5 position of the basic core; synthesis of the target compounds in the one-pot or multistage reactions or transformation of other related heterocycles. The most prominent pharmacological profiles of 5-ene derivatives of different 4-thiazolidinone subtypes belonging to hit-, lead-compounds, drug-candidates and drugs as well as the most studied targets have been discussed. Currently target compounds (especially 5-en-rhodanines) are assigned as frequent hitters or pan-assay interference compounds (PAINS) within high-throughput screening campaigns. Nevertheless, the crucial impact of the presence/nature of C5 substituent (namely 5-ene) on the pharmacological effects of 5-ene-4-thiazolidinones was confirmed by the numerous listed findings from the original articles. The main directions for active 5-ene-4-thiazolidinones optimization have been shown: i) complication of the fragment in the C5 position; ii) introduction of the substituents in the N3 position (especially fragments with carboxylic group or its derivatives); iii) annealing in complex heterocyclic systems; iv) combination with other pharmacologically attractive fragments within hybrid pharmacophore approach. Moreover, the utilization of 5-ene-4-thiazolidinones in the synthesis of complex compounds with potent pharmacological application is described. The chemical transformations cover mainly the reactions which involve the exocyclic double bond in C5 position of the main core and correspond to the abovementioned direction of the 5-ene-4-thiazolidinone modification.

Discovery of a COX-2 selective inhibitor hit with anti-inflammatory activity and gastric ulcer protective effect

AIM

A novel series of 2-arylimino-5-arylidenethiazolidin-4-ones 12a-n were synthesized and all the target compounds were fully characterized by IR, ¹H NMR, ¹³C NMR, mass spectroscopy and elemental analysis. Materials & methods: All the target compounds were evaluated for their COX inhibition by enzyme immunoassay kit and in vivo anti-inflammatory activity.

RESULTS

Tested compounds were found more potent inhibitors of COX-2 (IC₅₀ = 0.54-3.14 µM) than COX-1 (IC₅₀ = 4.97-11.52 µM). The ulcerogenic liability of compounds 12(d, e, f, h, k, m) was performed and showed gastric safety more than or comparable to celecoxib.

CONCLUSION

In addition, docking study of the most potent and selective compound 12h into COX-2 active site revealed that this target compound assumed interactions and binding pattern similar to that of as a cocrystallized ligand bromocelecoxib (S-58).

Synthesis and anticancer activity of novel quinazolinone-based rhodanines

Background

Rhodanines and quinazolinones have been reported to possess various pharmacological activities.

Results

A novel series of twenty quinazolinone-based rhodanines were synthesized via Knoevenagel condensation between 4-[3-(substitutedphenyl)-3,4-dihydro-4-oxoquinazolin-2-yl)methoxy]substituted-benzaldehydes and rhodanine. Elemental and spectral analysis were used to confirm structures of the newly synthesized compounds. The newly synthesized compounds were biologically evaluated for in vitro cytotoxic activity against the human fibrosarcoma cell line HT-1080 as a preliminary screen using the MTT assay.

Conclusions

All the target compounds were active, displaying IC₅₀ values roughly in the range of 10–60 µM. Structure–activity relationship study revealed that bulky, hydrophobic, and electron withdrawing substituents at the para-position of the quinazolinone 3-phenyl ring as well as methoxy substitution on the central benzene ring, enhance cytotoxic activity. The four most cytotoxic compounds namely, 45, 43, 47, and 37 were further tested against two human leukemia cell lines namely, HL-60 and K-562 and showed cytotoxic activity in the low micromolar range with compound 45 being the most active, having IC₅₀ values of 1.2 and 1.5 μM, respectively. Interestingly, all four compounds were devoid of cytotoxicity against normal human fibroblasts strain AG01523, indicating that the synthesized rhodanines may be selectively toxic against cancer cells. Mechanistic studies revealed that the most cytotoxic target compounds exhibit pro-apoptotic activity and trigger oxidative stress in cancer cells.

Recent developments with rhodanine as a scaffold for drug discovery

INTRODUCTION

Rhodanines, as one of the 4-thiazolidinones subtypes, are recognized as privileged heterocycles in medicinal chemistry. The main achievements include the development of drug-like molecules with numerous biological activities as well as approved drugs. Among rhodanines, 5-ene-rhodanines are of special interest, and are often claimed as pan assay interference compounds due to Michael acceptor functionality. Areas covered: Herein, the synthetic protocols for rhodanines and their transformation are reviewed. Biological activity is briefly discussed as well as biotargets, mode of actions and optimization directions. Furthermore, the utilization of 5-ene-rhodanines in Michael additions are discussed while both pro and contra arguments have been outlined within medicinal chemistry application. Expert opinion: Rhodanines remain privileged heterocycles in drug discovery. They are accessible building blocks for optimization and transformation into related heterocycles, simplified analogues and fused heterocycles with a thiazolidine framework. Michael acceptor functionality, as well as the thesis about low selectivity towards biotargets of rhodanines, must be confirmed experimentally and it cannot be based on just the presence of conjugated α,β-unsaturated carbonyl. Moreover, the positive aspects of Michael acceptors must be considered as well as their multitarget properties. New criteria for target affinity must be found. In conclusion, rhodanines are generally not problematic per se.

Design, synthesis and biological evaluation of some novel sulfonamide derivatives as apoptosis inducers

Several novel thiazolidinone and fused thiazolidinone derivatives bearing benzenesulfonamide moiety were synthesized and confirmed via spectral and elemental analyses. The newly synthesized compounds were evaluated for their cytotoxic activity on colorectal cancer cell line (Caco-2). All the synthesized compounds showed better activity than the reference standards (Doxorubicin and 5-FU). Investigation of the apoptotic activity of the most active compounds revealed that compounds 3a, 5a, 5c and 6c activate both caspase-3 and Fas-ligand in Caco-2 cell line. Compound 3a was the most active compound with caspase-3 concentration of 0.43 nmol/mL and Fas-ligand concentration of 775.2 pg/mL in treated Caco-2 cells. Compound 3a was radiolabeled with ^99mTc and its biodistribution pattern was evaluated in vivo using normal Swiss Albino mice. ^99mTc-compound 3a complex didn't exhibit any accumulation in any body organs except for its accumulation in the colon; target organ; where it showed 8.97 ± 1.35 %ID/g at 15min p. i. that elevated till 16.02 ± 2.43 %ID/g at 120min p. i.

Structure-activity relationship (SAR) study and design strategies of nitrogen-containing heterocyclic moieties for their anticancer activities

The present review article offers a detailed account of the design strategies employed for the synthesis of nitrogen-containing anticancer agents. The results of different studies describe the N-heterocyclic ring system is a core structure in many synthetic compounds exhibiting a broad range of biological activities. Benzimidazole, benzothiazole, indole, acridine, oxadiazole, imidazole, isoxazole, pyrazole, triazoles, quinolines and quinazolines including others drugs containing pyridazine, pyridine and pyrimidines are covered. The following studies of these compounds suggested that these compounds showed their antitumor activities through multiple mechanisms including inhibiting protein kinase (CDK, MK-2, PLK1, kinesin-like protein Eg5 and IKK), topoisomerase I and II, microtubule inhibition, and many others. Our concise representation exploits the design and anticancer potency of these compounds. The direct comparison of anticancer activities with the standard enables a systematic analysis of the structure-activity relationship among the series.

LNO3 AND L3 Are Associated With Antiproliferative And Pro-Apoptotic Action In Hepatoma Cells

The identification of antitumoral substances is the focus of intense biomedical research. Two structural analogues of thalidomide, LNO3 and L3, are two synthetic compounds that might possess such antitumor properties. We evaluated the toxicological effects of these substances, including cytotoxicity, genotoxicity and induction of apoptosis in HTC cells. Additionally, the production of free radicals (nitric oxide and superoxide) was investigated, and the expression of caspases genes 3, 8, and 9 were determined by RT-qPCR. The compounds exhibited cytotoxic effects that resulted in inhibited cell proliferation. LNO3 showed to be more effective and toxic than L3 in all assays. LNO3 stimulated the release of NO and superoxide, which was accompanied by the formation of peroxynitrite. Apoptosis was induced in a dose-dependent manner by both compounds; however, the expression of caspases 3, 8 and 9 was unchanged. These results suggested that L3 and LNO3 possess antiproliferative and pro-apoptotic effects in HTC cells. Additionally, although they exhibited cytotoxicity, L3 and LNO3 might be useful coadjuvants in tumor treatment studies.

Novel tetrazoloquinoline-rhodanine conjugates: Highly efficient synthesis and biological evaluation

In search of new active molecules against Mycobacterium tuberculosis (MTB) H37Ra and Mycobacterium bovis BCG, a small focused library of rhodanine incorporated tetrazoloquinoline has been efficiently synthesized by using [HDBU][HSO4] acidic ionic liquid. The compound 3c found to be promising inhibitor of MTB H37Ra and M. bovis BCG characterized by lower MIC values 4.5 and 2.0 μg/mL, respectively. The active compounds were further tested for cytotoxicity against HeLa, THP-1, A549 and PANC-1 cell lines using MTT assay and showed no significant cytotoxic activity at the maximum concentration evaluated. Again, the synthesized compounds were found to have potential antifungal activity. Furthermore, to rationalize the observed biological activity data, the molecular docking study also been carried out against a potential target Zmp1 enzyme of MTB H37Ra, which revealed a significant correlation between the binding score and biological activity for these compounds. The results of in vitro and in silico study suggest that these compounds possess ideal structural requirement for the further development of novel therapeutic agents.

Crystal structure of (Z)-5-(4-chlorobenzylidene)-2-thioxothiazolidin-4-one —dimethylsulfoxide (1:1), C12H12ClNO2S3

C12H12ClNO2S3, triclinic, P1̅ (no. 2), a = 4.4065(7) Å, b = 12.326(2) Å, c = 13.399(2) Å, β = 96.032(6)°, V = 718.2(2) Å3, Z = 2, R gt (F) = 0.0668, wR( F 2 ) = 0.164, T = 100 K.

Novel rhodanines with anticancer activity: design, synthesis and CoMSIA study

A library of novel rhodanines are reported for their anticancer activity along with the 3D QSAR.

DABCO-catalyzed consecutive one pot four-component protocol for the synthesis of a novel class of (Z)-5-(3-hydroxy-2-oxoindolin-3-yl)-2-iminothiazolidin-4-ones

A DABCO catalyzed, novel and efficient one-pot, four component protocol has been developed for the synthesis of (Z)-5-(3-hydroxy-2-oxoindolin-3-yl)-2-iminothiazolidin-4-one scaffolds under metal-free conditions.

Azole-based compounds as antiamoebic agents: a perspective using theoretical calculations

Diseases caused by protozoal organisms are responsible for significant mortality and morbidity worldwide. Amoebiasis caused byEntamoeba histolyticais an example of such diseases.

Stereochemical Investigations of Diastereomeric N-[2-(Aryl)-5-methyl-4-oxo-1,3-thiazolidine-3-yl]-pyridine-3-carboxamides by Nuclear Magnetic Resonance Spectroscopy (1D and 2D)

Some new N-[2-(aryl)-5-methyl-4-oxo-1,3-thiazolidine-3-yl]-pyridine-3-carboxamides were synthesized and their structures were investigated by IR, NMR (1H, 13C, and 2D), and mass spectra. The presence of C-2 and C-5 stereogenic centers on the thiazolidinone ring resulted in diastereoisomeric pairs. The configurations of two stereogenic centers were assigned based upon 1H NMR analysis of coupling constants and 2D nuclear overhauser enhancement spectroscopy (NOESY) experiment. Resolution of the diastereoisomers was performed by high performance liquid chromatography (HPLC) using a chiral stationary phase.

Click with a boronic acid handle: a neighboring group-assisted click reaction that allows ready secondary functionalization

The feasibility of a neighboring boronic acid-facilitated facile condensation of an aldehyde is described. This reaction is bio-orthogonal, complete at room temperature within minutes, and suitable for bioconjugation chemistry. The boronic acid group serves the dual purpose of catalyzing the condensation reaction and being a handle for secondary functionalization.

Synthesis, carbonic anhydrase inhibition and cytotoxic activity of novel chromone-based sulfonamide derivatives

Four series of sulfonamides incorporating chromone moieties were synthesized and assessed for their cytotoxic activity against MCF-7 and A-549 cell lines, considering the fact that some of these tumors overexpress isoforms of carbonic anhydrase (CA, EC 4.2.1.1) which is inhibited by sulfonamides. Most new sulfonamides showed weak inhibitory activity against the offtarget, cytosolic isoforms hCA I, II but effectively inhibited the tumor-associated hCA IX and XII. The most active compounds featured a primary SO2NH2 group and were active in the low micromolar range against MCF-7 and A-549 cell lines. Compound 4a showed IC50 of 0.72 and 0.50 μM against MCF-7 and A-549 cell lines, respectively, and was further evaluated for its proapoptotic activity which proved enhanced in both tumor types.

A facile synthesis and antimicrobial activity evaluation of sydnonyl-substituted thiazolidine derivatives

Some new sydnonyl-substituted thiazolidine derivatives were synthesized in high yields by the modified Knoevenagel condensation of 3-aryl-4-formylsydnones with thiazolidine-2,4-dione and 2-thioxo-thiazolidine-4-one, respectively. All the synthesized thiazolidine derivatives were screened by paper-disc method to identify their antimicrobial activities against three bacteria viz. Staphylococcus aureus, Proteus vulgaris and Escherichia coli, and two fungal cultures viz. Aspergillus niger and Penicillium citrinum. The reference drugs were Norfloxacin and Griseofulvin, respectively. The screening data indicated that the tested sydnonyl-substituted thiazolidine derivatives exhibited no obvious antibacterial activity compared with the standard drug Norfloxacin. However, thiazolidine derivatives displayed significant antifungal activities against Penicillium citrinum and Aspergillus niger. Notably, all of the tested compounds showed growth inhibitory activity 1.5-4.4 times higher than that of the standard drug Griseofulvin against the two fungi.

Crystal structure of (E)-2-{[(6-meth-oxy-1,3-benzo-thia-zol-2-yl)imino]-meth-yl}phenol

The title compound, C15H12N2O2S, crystallizes in the ortho-rhom-bic space group Pna21 , with two mol-ecules in the asymmetric unit (Z' = 2). Each mol-ecule consists of a 2-hy-droxy Schiff base moiety linked through a spacer to a 2-amino-benzo-thia-zole moiety. Each mol-ecule contains an intra-molecular hydrogen bond between the -OH group and imine N atom, forming a six-membered ring. The two independent molecules are linked by a pair of C-H⋯O hydrogen bonds, forming dimers with an R (2) 2(20) ring motif. These dimers are further lined into sheets in the ab plane by weak inter-molecular C-H⋯N inter-actions. The structure was refined as an inversion twin.