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

Design and Discovery of New Dual Carbonic Anhydrase IX and VEGFR-2 Inhibitors Based on the Benzenesulfonamide-Bearing 4-Thiazolidinones/2,4-Thiazolidinediones Scaffold

Dual-targeting drug design has become a popular approach in investigating and developing potent anticancer agents. In this regard, carbonic anhydrase (CAIX) and vascular endothelial growth factor receptor (VEGFR-2) are emerging as highly effective targets in the battle against cancer. In the present study, two series of 4-thiazolidinones/2,4-thiazolidinediones carrying 2-methylbenzenesulfonamide derivatives were designed and synthesized as potential dual CAIX/VEGFR-2 inhibitors. All the target compounds were evaluated against CAIX enzyme compared to dorzolamide and acetazolamide, subsequently the most potent CAIX inhibitors (3a, 3b, 3o, 6d, 6g, and 6i) were selected to evaluate their inhibitory activity against VEGFR-2 using sorafenib as a reference drug. These compounds were also evaluated against MCF-7 breast cancer cells and the murine fibroblast 3T3 cell line. According to the results, 3b (CAIX IC50 = 0.035 µM, VEGFR-2 IC50 = 0.093 µM) and 6i (CAIX IC50 = 0.041 µM, VEGFR-2 IC50 = 0.048 µM) emerged the most potent compounds against CAIX and VEGFR-2. Furthermore, docking studies of selected compounds were performed with the CAIX and the tyrosine kinase domain of VEGFR-2 to comprehend the ligand-binding interactions. Physicochemical predictions were examined using in silico techniques. In conclusion, these scaffolds present promising leads and furnish promising chemical backbones for the design of potent dual CAIX and VEGFR-2 inhibitors.b.

New Structural Features of Isatin Dihydrothiazole Hybrids for Selective Carbonic Anhydrase Inhibitors

Chemotherapeutic agents have remained the first-line treatment option for advanced-stage cancers when surgery or radiation therapy is not viable. Human carbonic anhydrase (hCA) isoforms IX and XII have been validated as anticancer targets. In particular, hCA IX is overexpressed in several solid tumor cells. As a result, selective isoform inhibitors with high potency and low toxicity are sought after. Pursuing our investigation on new scaffolds as hCA-selective inhibitors, a new series of isatin thiazolidinone hybrids has been designed and synthesized. Their biological activity and selectivity toward hCA I, hCA II, hCA IX, and hCA XII were investigated. The results revealed an inhibitory activity in the nanomolar range on carbonic anhydrases IX and XII, and the nature of substitution in positions 3 and 5 of thiazolidinone appears to be crucial for the compounds' selectivity. Docking experiments have been applied to predict the binding mode of these new, promising derivatives.

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

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

Privileged Scaffold Hybridization in the Design of Carbonic Anhydrase Inhibitors

Human Carbonic Anhydrases (hCA) are enzymes that contribute to cancer's development and progression. Isoforms IX and XII have been identified as potential anticancer targets, and, more specifically, hCA IX is overexpressed in hypoxic tumor cells, where it plays an important role in reprogramming the metabolism. With the aim to find new inhibitors towards IX and XII isoforms, the hybridization of the privileged scaffolds isatin, dihydrothiazole, and benzenesulfonamide was investigated in order to explore how it may affect the activity and selectivity of the hCA isoforms. In this respect, a series of isatin thiazolidinone hybrids have been designed and synthesized and their biological activity and selectivity on hCA I, hCA II, hCA IX, and hCA XII explored. The new compounds exhibited promising inhibitory activity results on isoforms IX and XII in the nanomolar range, which has highlighted the importance of substituents in the isatin ring and in position 3 and 5 of thiazolidinone. In particular, compound 5g was the most active toward hCA IX, while 5f was the most potent inhibitor of hCA XII within the series. When both potency and selectivity were considered, compound 5f appeared as one of the most promising. Additionally, our investigations were supported by molecular docking experiments, which have highlighted the putative binding poses of the most promising compound.

Probing benzenesulfonamide-thiazolidinone hybrids as multitarget directed ligands for efficient control of type 2 diabetes mellitus through targeting the enzymes: α-glucosidase and carbonic anhydrase II

Diabetes mellitus is a chronic metabolic disorder characterized by improper expression/function of a number of key enzymes that can be regarded as targets for anti-diabetic drug design. Herein, we report the design, synthesis, and biological assessment of two series of thiazolidinone-based sulfonamides 4a-l and 5a-c as multitarget directed ligands (MTDLs) with potential anti-diabetic activity through targeting the enzymes: α-glucosidase and human carbonic anhydrase (hCA) II. The synthesized sulfonamides were evaluated for their inhibitory activity against α-glucosidase where most of the compounds showed good to potent activities. Compounds 4d and 4e showed potent inhibitory activities (IC50 = 0.440 and 0.3456 μM), comparable with that of the positive control (acarbose; IC50 = 0.420 μM). All the synthesized derivatives were also tested for their inhibitory activities against hCA I, II, IX, and XII. They exhibited different levels of inhibition against these isoforms. Compound 4d outstood as the most potent one against hCA II with Ki equals to 7.0 nM, more potent than the reference standard (acetazolamide; Ki = 12.0 nM). In silico studies for the most active compounds within the active sites of α-glucosidase and hCA II revealed good binding modes that can explain their biological activities. MM-GBSA refinements and molecular dynamic simulations were performed on the top-ranking docking pose of the most potent compound 4d to confirm the formation of stable complex with both targets. Compound 4d was screened for its in vivo antihyperglycemic efficacy by using the oral glucose tolerance test. Compound 4d decreased blood glucose level to 217 mg/dl, better than the standard acarbose (234 mg/dl). Hence, this revealed its synergistic mode of action on post prandial hyperglycemia and hepatic gluconeogenesis. Thus, these benzenesulfonamide thiazolidinone hybrids could be considered as promising multi-target candidates for the treatment of type II diabetes mellitus.

Design, synthesis and mechanism study of coumarin-sulfonamide derivatives as carbonic anhydrase IX inhibitors with anticancer activity

In this study, twenty-nine coumarin-3-sulfonamide derivatives, twenty-seven of which are original were designed and synthesized. Cytotoxicity assay indicated that most of these derivatives exhibited moderated to good potency against A549 cells. Among them, compound 8q showed potent inhibition against the four tested cancer cell lines, especially A549 cells with IC50 value of 6.01 ± 0.81 μM, and much lower cytotoxicity on the normal cells was observed compared to the reference compounds. Bioinformatics analysis revealed human carbonic anhydrase IX (CAIX) was highly expressed in lung adenocarcinoma (LUAD) and associated with poor prognosis. The inhibitory activity of compound 8q against CAIX was assessed by using molecular docking and molecular dynamics simulations, which revealed prominent interactions of both compound 8q and CAIX at the active site and their high affinity. The results of ELISA assays verified that compound 8q possessed strong inhibitory activity against CAIX and high subtype selectivity, and could also down-regulate the expression of CAIX in A549 cells. Furthermore, the significant inhibitory effects of compound 8q on the migration and invasion of A549 cells were also found. After treatment with compound 8q, intracellular reactive oxygen species (ROS) levels increased and mitochondrial membrane potential (MMP) decreased. Mechanistic investigation using western blotting revealed compound 8q exerted the anti-migrative and anti-invasive effects probably through mitochondria-mediated PI3K/AKT pathway by targeting CAIX. In summary, coumarin-3-sulfonamide derivatives were developed as potential and effective CAIX inhibitors, which were worthy of further investigation.

Combining BNCT with carbonic anhydrase inhibition for mesothelioma treatment: Synthesis, in vitro, in vivo studies of ureidosulfamido carboranes

Mesothelioma is a malignant neoplasm of mesothelial cells caused by exposure to asbestos. The average survival time after diagnosis is usually nine/twelve months. A multi-therapeutic approach is therefore required to treat and prevent recurrence. Boronated derivatives containing a carborane cage, a sulfamido group and an ureido functionality (CA-USF) have been designed, synthesised and tested, in order to couple Boron Neutron Capture Therapy (BNCT) and the inhibition of Carbonic Anhydrases (CAs), which are overexpressed in many tumours. In vitro studies showed greater inhibition than the reference drug acetazolamide (AZ). To increase solubility in aqueous media, CA-USFs were used as inclusion complexes of hydroxypropyl β-cyclodextrin (HP-β-CD) in all the inhibition and cell experiments. BNCT experiments carried out on AB22 (murine mesothelioma) cell lines showed a marked inhibition of cell proliferation by CA-USFs, and in one case a complete inhibition of proliferation twenty days after neutron irradiation. Finally, in vivo neutron irradiation experiments on a mouse model of mesothelioma demonstrated the efficiency of combining CA IX inhibition and BNCT treatment. Indeed, a greater reduction in tumour mass was observed in treated mice compared to untreated mice, with a significant higher effect when combined with BNCT. For in vivo experiments CA-USFs were administered as inclusion complexes of higher molecular weight β-CD polymers thus increasing the selective extravasation into tumour tissue and reducing clearance. In this way, boron uptake was maximised and CA-USFs demonstrated to be in vivo well tolerated at a therapeutic dose. The therapeutic strategy herein described could be expanded to other cancers with increased CA IX activity, such as melanoma, glioma, and breast cancer.

pH regulators and their inhibitors in tumor microenvironment

As an important characteristic of tumor, acidic tumor microenvironment (TME) is closely related to immune escape, invasion, migration and drug resistance of tumor. The acidity of the TME mainly comes from the acidic products produced by the high level of tumor metabolism, such as lactic acid and carbon dioxide. pH regulators such as monocarboxylate transporters (MCTs), carbonic anhydrase IX (CA IX), and Na+/H+ exchange 1 (NHE1) expel protons directly or indirectly from the tumor to maintain the pH balance of tumor cells and create an acidic TME. We review the functions of several pH regulators involved in the construction of acidic TME, the structure and structure-activity relationship of pH regulator inhibitors, and provide strategies for the development of small-molecule antitumor inhibitors based on these targets.

Substituted furan sulfonamides as carbonic anhydrase inhibitors: Synthesis, biological and in silico studies

Carbonic Anhydrases (CAs) are a large family of zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide involved in several of biological processes, such as respiration, calcification, acid-base balance, bone resorption, and the formation of aqueous humor, cerebrospinal fluid, saliva, and gastric acid. They show wide diversity in tissue distribution and in their subcellular localization. Fifteen novel furyl sulfonamides were designed, synthesized and evaluated against four human isoforms: hCA I, hCA II, hCA IV and hCA IX. Compounds appeared to be very active mostly against hCAI (8) and hCA IV (11) isoforms being more potent than reference drug acetazolamide (AAZ). It should be mentioned that four compounds were more active than AAZ against hCA IX isoform, with compound 13d to be selective against hCA I (SI 70), hCA II (SI 13.5) and hCA IV (SI 20). Furthermore, docking was performed for some of these compounds on all isoforms I order to understand the possible interactions with the active site. The most active compounds showed good bioavailability and drug likeness scores.

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, Molecular Docking Study and Biological Evaluation of Novel γ-Carboline Derivatives of Latrepirdine (Dimebon) as Potent Anticancer Agents

A series of novel γ-Carboline derivatives were designed and synthesized using the Suzuki coupling reaction to identify the leads for the activity against cancer. Interestingly, these compounds were tested for their anticancer activity against the cell lines, particularly human cancer cell lines MCF7 (breast), A549 (lung), SiHa (cervix), and Colo-205 (colon). Most of the γ-Carboline derivatives showed potent inhibitory activity in four cancer cell lines, according to in vitro anticancer activity screening. Two compounds, specifically LP-14 and LP-15, showed superior activity in cancer cell lines among the γ-Carboline derivatives from LP-1 to LP-16. Additionally, the compound LP-14, LP-15 and Etoposide carried out molecular docking studies on human topoisomerase II beta in complex with DNA and Etoposide (PDB ID: 3QX3). The docking studies' results showed that the derivative LP-15 was strongly bound with the receptor amino acid residues, including Glu477 and DC8 compared with the marked drug Etoposide.

Synthesis of 2-iminothiazolidin-4-ones via copper-catalyzed [2 + 1 + 2] tandem annulation

In this paper, an efficient synthesis of 2-iminothiazolidin-4-ones through a copper-catalyzed tandem annulation reaction of alkyl amines, isothiocyanates and diazo acetates is presented. Notable advantages of this [2 + 1 + 2] cyclization methodology include readily accessible starting materials, simple operation, mild reaction conditions, high yields, step-economy and diverse functional group tolerance. In addition, the reaction is applicable to the gram scale synthesis and the preparation of bioactive molecules.

Discovery of 5-Methylthiazole-Thiazolidinone Conjugates as Potential Anti-Inflammatory Agents: Molecular Target Identification and In Silico Studies

A series of previously synthesized 5-benzyliden-2-(5-methylthiazole-2-ylimino)thiazoli- din-4-one were evaluated for their anti-inflammatory activity on the basis of PASS predictive outcomes. The predictive compounds were found to demonstrate moderate to good anti-inflammatory activity, and some of them displayed better activity than indomethacin used as the reference drug. Structure-activity relationships revealed that the activity of compounds depends not only on the nature of the substituent but also on its position in the benzene ring. The most active compounds were selected to investigate their possible mechanism of action. COX and LOX activity were determined and found that the title compounds were active only to COX-1 enzymes with an inhibitory effect superior to the reference drug naproxen. As for LOX inhibitory activity, the derivatives failed to show remarkable LOX inhibition. Therefore, COX-1 has been identified as the main molecular target for the anti-inflammatory activity of our compounds. The docking study against COX-1 active site revealed that the residue Arg 120 was found to be responsible for activity. In summary, the 5-thiazol-based thiazolidinone derivatives have been identified as a novel class of selective COX-1 inhibitors.

Carbonic anhydrase IX: A tumor acidification switch in heterogeneity and chemokine regulation

The primary physiological process of respiration produces carbon dioxide (CO₂) that reacts with water molecules which subsequently liberates bicarbonate (HCO-₃) and protons. Carbonic anhydrases (CAs) are the primary catalyst involved in this conversion. More than 16 isoforms of human CAs show organ or subcellular specific activity. Dysregulation of each CA is associated with multiple pathologies. Out of these members, the overexpression of membrane-bound carbonic anhydrase IX (CAIX) is associated explicitly with hypoxic tumors or various solid cancers. CAIX helps tumors deal with higher CO₂ by sequestering it with bicarbonate ions and helping cancer cells to grow in a comparatively hypoxic or acidic environment, thus acting as a pH adaptation switch. CAIX-mediated adaptations in cancer cells include angiogenesis, metabolic alterations, tumor heterogeneity, drug resistance, and regulation of cancer-specific chemokines. This review comprehensively collects and describe the cancer-specific expression mechanism and role of CAIX in cancer growth, progression, heterogeneity, and its structural insight to develop future combinatorial targeted cancer therapies.

4-Thiazolidinone-Bearing Hybrid Molecules in Anticancer Drug Design

Oncological diseases have currently reached an epidemic scale, especially in industrialized countries. Such a situation has prompted complex studies in medicinal chemistry focused on the research and development of novel effective anticancer drugs. In this review, the data concerning new 4-thiazolidinone-bearing hybrid molecules with potential anticancer activity reported during the period from the years 2017-2022 are summarized. The main emphasis is on the application of molecular hybridization methodologies and strategies in the design of small molecules as anticancer agents. Based on the analyzed data, it was observed that the main directions in this field are the hybridization of scaffolds, the hybrid-pharmacophore approach, and the analogue-based drug design of 4-thiazolidinone cores with early approved drugs, natural compounds, and privileged heterocyclic scaffolds. The mentioned design approaches are effective tools/sources for the generation of hit/lead compounds with anticancer activity and will be relevant to future studies.

Synthesis and anticancer activity of new benzensulfonamides incorporating s-triazines as cyclic linkers for inhibition of carbonic anhydrase IX

Limited presence of hCA IX in normal physiological tissues and their overexpression only in solid hypoxic tumors made this isoform excellent possible target for developing new anticancer agents. We reported designing and synthesis of two novel series of benzenesulfonamides derivatives as hCA IX inhibitors bearing rigid cyclic linkers (1,3,5-dihydrotriazine in series A and 1,3,5-triazine in series B) in replace of traditional linear linkers. Also, novel cyanoethenyl spacer was assembled next to the 1,3,5-triazine linker in series B. Target compounds of series (A) and (B) were screened against four hCA isoforms. Human CA IX efficiently inhibited in series (A) by compound 5a (K_I = 134.8 nM). Meanwhile, in series (B) the most active inhibitor was 12i (K_I = 38.8 nM). US-NCI protocol was followed to evaluate the anticancer activity of target compounds against panel of sixty cancer cell lines. Compound 12d, exposed the best activity towards breast cancer (MDA-MB-468) with GI% = 62%. The most active analogues, 12d and 12i were further screened for in vitro cytotoxic activity under hypoxic condition against breast cancer (MDA-MB-468) (IC₅₀ = 3.99 ± 0.21 and 1.48 ± 0.08 µM, respectively) and leukemia (CCRF-CM) cell line (IC₅₀ = 4.51 ± 0.24 and 9.83 ± 0.52 µM, respectively). In addition, 12d arrested breast cancer MDA-MB-468 cell cycle in G0-G1 and S phases and induced its apoptosis which indicated by increasing the level of cleaved caspases 3 and 9. Molecular docking was performed for selected analogues to understand their biological alterations. This study revealed that insertion of 1,3,5-triazines as cyclic linkers enhanced the significant anticancer and hCA IX inhibition activity of benzenesulfonamides.

Isoxazole Derivatives against Carbonic Anhydrase: Synthesis, Molecular Docking, MD Simulations, and Free Energy Calculations Coupled with In Vitro Studies

Heterocyclic compounds with a five-membered ring as a core, particularly those containing more than one heteroatom, have a wide spectrum of biological functions, especially in enzyme inhibition. In this study, we present the synthesis of five-membered heterocyclic isoxazole derivatives via sonication of ethyl butyrylacetate with aromatic aldehyde in the presence of a SnII-Mont K10 catalyst. The synthesized compounds were characterized using sophisticated spectroscopic methods. In vitro testing of the compounds reveals three derivatives with significant inhibitory action against carbonic anhydrase (CA) enzyme. The compound AC2 revealed the most promising inhibitory activity against CA among the entire series, with an IC₅₀ = 112.3 ± 1.6 μM (%_inh = 79.5) followed by AC3 with an IC₅₀ = 228.4 ± 2.3 μM (%_inh = 68.7) compared to the standard with 18.6 ± 0.5 μM (%_inh = 87.0). Molecular docking (MD) study coupled with extensive MD simulations (400 ns) and MMPBSA study fully supported the in vitro enzyme inhibition results, evident from the computed ΔG _bind (AC2 = -13.53 and AC3 = -12.49 kcal/mol). The in vitro and in silico studies are also augmented by a fluorescence-based enzymatic assay in which compounds AC2 and AC3 showed significant fluorescence enhancement. Therefore, on the basis of the present study, it is inferred that AC2 and AC3 may serve as a new framework for designing effective CA inhibitors.

Novel 3-(6-methylpyridin-2-yl)coumarin-based chalcones as selective inhibitors of cancer-related carbonic anhydrases IX and XII endowed with anti-proliferative activity

Carbonic anhydrases (CAs) are one of the promising targets for the development of anticancer agents. CA isoforms are implicated in various physiological processes and are expressed in both normal and cancerous cells. Thus, non-isoform selective inhibitors are associated with several side effects. Consequently, designing selective inhibitors towards cancer-related hCA IX/XII rather than the ubiquitous cytosolic isozymes hCA I and II is the main research objective in the field. Herein, a new series of 3-(6-methylpyridin-2-yl)coumarin derivatives 3 and 5a–o was designed and synthesised. The CA inhibition activities for the synthesised coumarins were analysed on isoforms hCA I, II, IX, and XII. Interestingly, both cancer-linked isoforms hCA IX/XII were inhibited by the prepared coumarins with inhibition constants ranging from sub- to low-micromolar range, whereas hCA I and II isoforms haven’t been inhibited up to 100 µM. Furthermore, the target coumarins were assessed for their antitumor activity on NCI-59 human cancer types.

Thiazolidin-4-Ones as Potential Antimicrobial Agents: Experimental and In Silico Evaluation

Herein, we report computational and experimental evaluations of the antimicrobial activity of twenty one 2,3-diaryl-thiazolidin-4-ones. All synthesized compounds exhibited an antibacterial activity against six Gram-positive and Gram-negative bacteria to different extents. Thus, the MIC was in the range of 0.008-0.24 mg/mL, while the MBC was 0.0016-0.48 mg/mL. The most sensitive bacterium was S. Typhimurium, whereas S. aureus was the most resistant. The best antibacterial activity was observed for compound 5 (MIC at 0.008-0.06 mg/mL). The three most active compounds 5, 8, and 15, as well as compound 6, which were evaluated against three resistant strains, MRSA, P. aeruginosa, and E. coli, were more potent against all bacterial strains used than ampicillin. The antifungal activity of some compounds exceeded or were equipotent with those of the reference antifungal agents bifonazole and ketoconazole. The best activity was expressed by compound 5. All compounds exhibited moderate to good drug-likeness scores ranging from -0.39 to 0.39. The docking studies indicated a probable involvement of E. coli Mur B inhibition in the antibacterial action, while CYP51 inhibition is likely responsible for the antifungal activity of the tested compounds. Finally, the assessment of cellular cytotoxicity of the compounds in normal human MRC-5 cells revealed that the compounds were not toxic.

Synthesis and exploration of configurational dynamics in equilibrating E/Z 2-aryliminothiazolidin-4-ones using NMR and estimation of thermodynamic parameters

NMR based in-depth exploration of stereodynamic behavior in equilibrating E/Z 2-aryliminothiazolidin-4-ones and determination of kinetic and thermodynamic parameters.

Discovery of Natural Compounds as Potential Inhibitors of Human Carbonic Anhydrase II: An Integrated Virtual Screening, Docking, and Molecular Dynamics Simulation Study

Carbonic anhydrase II (CAII) is one of the zinc metalloenzymes that catalyze the reversible hydration of carbon dioxide, leading to the formation of bicarbonate and proton. CAII plays a significant role in health and disease. For example, CAII helps to maintain eye pressure while regulating the pH of the tumor microenvironment, and by extension, contributing to cancer progression. Owing to its remarkable role in cancer, visual health, and other human diseases, CAII can serve as an attractive therapeutic target. We report an original study based on high-throughput virtual screening of natural compounds from the ZINC database in search of potential inhibitors of CAII. We selected the hits based on the physicochemical, absorption, distribution, metabolism, excretion, and toxicity (ADMET) properties, pan-assay interference compound (PAINS) patterns, and interaction analysis. Importantly, two natural compounds were identified, ZINC08918123 and ZINC00952700, bearing considerable affinity and specific interactions to the residues of the CAII-binding pocket with well-organized conformational fitting compatibility. We investigated the conformational dynamics of CAII in complex with the identified compounds through molecular dynamics simulation, which revealed the formation of a stable complex preserved throughout the 100 ns trajectories. The stability of the protein/ligand complexes is maintained by significant numbers of noncovalent interactions throughout the simulations. In conclusion, natural compounds identified in the present study specifically and computer-assisted drug design broadly offer a reliable resource and strategy to discover potential promising therapeutic inhibitors of CAII to cure various cancers and glaucoma after further experimental validation and clinical studies.

Role of 4-Thiazolidinone Scaffold in Targeting Variable Biomarkers and Pathways Involving Cancer

BACKGROUND

Cancer can be considered as a genetic as well as a metabolic disorder. Current cancer treatment scenario looks like aggravating tumor cell metabolism, causing the disease to progress even with greater intensity. The cancer therapy is restricted to limitations of poor patient compliance due to toxicities to normal tissues and multi-drug resistance development. There is an emerging need for cancer therapy to be more focused on the better understanding of genetic, epigenetic and transcriptional changes resulting in cancer progression and their relationship with treatment sensitivity.

OBJECTIVE

The 4-thiazolidinone nucleus possesses marked anticancer potential towards different biotargets, thus targeting different cancer types like breast, prostate, lung, colorectal and colon cancers, renal cell adenocarcinomas and gliomas. Therefore, conjugating the 4-thiazolidinone scaffold with other promising moieties or by directing the therapy towards targeted drug delivery systems like the use of nanocarrier systems, can provide the gateway for optimizing the anticancer efficiency and minimizing the adverse effects and drug resistance development, thus providing stimulus for personalized pharmacotherapy.

METHODS

An exhaustive literature survey has been carried out to give an insight into the anticancer potential of the 4-thiazolidinone nucleus either alone or in conjugation with other active moieties, with the mechanisms involved in preventing proliferation and metastasis of cancer covering a vast range of publications of repute.

CONCLUSION

This review aims to summarise the work reported on anticancer activity of 4-thiazolidinone derivatives covering various cancer biomarkers and pathways involved, citing the data from 2005 till now, which may be beneficial to the researchers for future development of more efficient 4-thiazolidinone derivatives.

Pyridine moiety: An insight into recent advances in treatment of cancer

The incidence of cancer is increasing worldwide, affecting a vast majority of the human population. As new different anticancer agents are being developed now, the requirement is to deal somehow with them and evaluate their safety. Among them, pyridine based drugs are contributing a lot, as it is one of the imperative pharmacophores occurring synthetically as well as naturally in heterocyclic compounds, and having a wide range of therapeutic applications in the area of drug discovery, thereby offering many chances for further improvement in antitumor agents via acting onto numerous receptors of extreme prominence. Many pyridine derivatives have been reported to inhibit enzymes, receptors and many other targets for controlling and curing the global health issue of cancer. Nowadays, in combination with other moieties, researchers are focusing on the development of pyridine-based new derivatives for cancer treatment. Therefore, this review sheds light on the recent therapeutic expansions of pyridine together with its molecular docking, structure-activity-relationship, availability in the market, and a summary of recently patented and published research works that shall jointly help the scientists to produce effective drugs with the desired pharmacological activity.

Design, synthesis and assessment of new series of quinazolinone derivatives as EGFR inhibitors along with their cytotoxic evaluation against MCF7 and A549 cancer cell lines

New acetamide (IV a-e) and 1,3-thiazolidinone derivatives (VII a-e) were designed, synthesized and assessed for their cytotoxic activity against MCF-7 and A549 cell lines along with their lead compounds (erlotinib and gefitinib). The newly designed compounds were prepared according to the adopted procedures in schemes 1 and 2 from their quinazolinone parents. 3D QSAR pharmacophore and docking molecular modeling protocols were conducted using Discovery Studio program, beside a full biological assay for these compounds. The cytotoxicity evaluation demonstrated that compounds IVb, IVc, VIIa, VIIb, VIId exhibited potent cytotoxic activities against both MCF-7 and A549 cell lines. Moreover, the molecular modeling studies corroborated to the affinity of the compounds towards EGFR. Consequently, these five compounds were then screened for their EGFR inhibition and evaluated as well for their toxicity to normal cells, which revealed that the acetamide derivative IVc and the thiazolidinone derivative VIIa were the most potent and least toxic. DNA flow cytometry analysis was conducted for compounds IVc and VIIa, which indicated that they both induced arrest at G2/M phase of the cell cycle.

In vivo and in vitro anti-inflammatory, antipyretic and ulcerogenic activities of pyridone and chromenopyridone derivatives, physicochemical and pharmacokinetic studies

Throughout this study, we present the victorious synthesis of a novel class of 2(1H)-pyridone molecules, bearing a 4-hydroxyphenyl moiety through a one-pot reaction of 2-cyano-N-(4-hydroxyphenyl)acetamide with cyanoacetamide, acetylacetone or ethyl acetoacetate, and their corresponding aldehydes. In addition, the chromene moiety was introduced into the pyridine skeleton through the cyclization of the cyanoacetamide 2 with salicylaldehyde, followed by treatment with malononitrile, ethyl cyanoacetate, and cyanoacetamide, in order to improve their biological behaviour. Due to their anti-inflammatory, ulcerogenic, and antipyretic characters, the target molecules have undergone in-vitro and in-vivo examination, that display promising results. Moreover, in order to predict the physicochemical and ADME traits of all synthesized compounds and standard reference drugs, paracetamol and phenylbutazone, the in-silico prediction methodology was provided.

New Substituted 5-Benzylideno-2-Adamantylthiazol[3,2-b][1,2,4]Triazol-6(5H)ones as Possible Anti-Inflammatory Agents

Background: Inflammation is a complex response to noxious stimuli promoted by the release of chemical mediators from the damaged cells. Metabolic products of arachidonic acid, produced by the action of cyclooxygenase and lipoxygenase, play important roles in this process. Several non-steroidal anti-inflammatory drugs act as cyclooxygenase inhibitors. However, almost all of them have undesired side effects. Methods: Prediction of the anti-inflammatory action of the compounds was performed using PASS Program. The anti-inflammatory activity was evaluated by the carrageenan paw edema test. COX and LOX inhibitory actions were tested using ovine COX-1, human recombinant COX-2 and soybean LOX-1, respectively. Docking analysis was performed using Autodock. Results: All designed derivatives had good prediction results according to PASS and were synthesized and experimentally evaluated. The compounds exhibited in vivo anti-inflammatory action with eleven being equal or better than indomethacin. Although, some of them had no or low inhibitory effect on COX-1/2 or LOX, certain compounds exhibited COX-1 inhibition much higher than naproxen and COX-2 inhibition, well explained by Docking analysis. Conclusions: A number of compounds with good anti-inflammatory action were obtained. Although, some exhibited remarkable COX inhibitory action this activity did not follow the anti-inflammatory results, indicating the implication of other mechanisms.

Medicinal attributes of pyridine scaffold as anticancer targeting agents

Background

The heterocyclic compounds particularly pyridine displayed clinical and biological implementation. Pyridine scaffolds have been detected in most relevant drug molecules that included pyridine provided a great possibility for treatment.

Main text

Pyridine-containing compounds have increasing importance for medicinal application as antiviral, anticholinesterase activities, antimalarial, antimicrobial, antidiabetic and anticancer. This has generated concern among researchers in synthesising a variety of pyridine derivatives.

Conclusion

This review focuses on different pyridine targets as anticancer and their pharmacophoric elements controlling its activity.

Neto JDB, de Abreu FC, Figueiredo IM, Carinhanha C. Santos J, Pessoa CDÓ, da Silva-Júnior EF, de Araújo-Júnior JX, M. de Aquino T. Synthesis of hybrids thiazole–quinoline, thiazole–indole and their analogs: in vitro anti-proliferative effects on cancer cell lines, DNA binding properties and molecular modeling

A quinoline–thiazole hybrid was synthesized, which showed cytotoxicity against the HL-60 cell line. Electrochemical and spectroscopic experiments suggested DNA as the biological target.

2-Aryl-3-(6-trifluoromethoxy)benzo[d]thiazole-based thiazolidinone hybrids as potential anti-infective agents: Synthesis, biological evaluation and molecular docking studies

The search for new antimicrobial agents is greater than ever due to the perpetual threat of multidrug resistance in known pathogens and the relentless emergence of new infections. In this manuscript, ten thiazole-based thiazolidinone hybrids bearing a 6-trifluoromethoxy substituent on the benzothiazole core were synthesized and evaluated against a panel of four bacterial strains Salmonella typhimurium, Staphylococcus aureus, Escherichia coli and Listeria monocytogenes and three resistant strains Pseudomonas aeruginosa, E. coli and MRSA. The evaluation of minimum bactericidal and minimum inhibitory concentrations was accomplished by microdilution assay. As reference compounds ampicillin and streptomycin were employed. All compounds displayed antibacterial efficiencies with MBCs/MICs at 0.25-1 mg/mL and 0.12-1 mg/mL respectively while ampicillin displayed MBCs/MICs at 0.15-0.3 mg/mL and at 0.1-0.2 mg/mL respectively. MICs/MBC of streptomycin varied from 0.05 to 0.15 mg/mL and from 0.1 to 0.3 mg/mL respectively. The best overall effect was observed for compound h4, while compound h1 exhibited the highest effective action against E. coli (MIC/MBC 0.12/0.25 mg/ml) among all tested compounds.

Heterocycle Compounds with Antimicrobial Activity

Background:

Bacterial infections are a growing problem worldwide causing morbidity and mortality mainly in developing countries. Moreover, the increased number of microorganisms, developing multiple resistances to known drugs, due to abuse of antibiotics, is another serious problem. This problem becomes more serious for immunocompromised patients and those who are often disposed to opportunistic fungal infections.

Objective:

The objective of this manuscript is to give an overview of new findings in the field of antimicrobial agents among five-membered heterocyclic compounds. These heterocyclic compounds especially five-membered attracted the interest of the scientific community not only for their occurrence in nature but also due to their wide range of biological activities.

Method:

To reach our goal, a literature survey that covers the last decade was performed.

Results:

As a result, recent data on the biological activity of thiazole, thiazolidinone, benzothiazole and thiadiazole derivatives are mentioned.

Conclusion:

It should be mentioned that despite the progress in the development of new antimicrobial agents, there is still room for new findings. Thus, research still continues.

Saturated Five-Membered Thiazolidines and Their Derivatives: From Synthesis to Biological Applications

In past decades, interdisciplinary research has been of great interest for scholars. Thiazolidine motifs behave as a bridge between organic synthesis and medicinal chemistry and compel researchers to explore new drug candidates. Thiazolidine motifs are very intriguing heterocyclic five-membered moieties present in diverse natural and bioactive compounds having sulfur at the first position and nitrogen at the third position. The presence of sulfur enhances their pharmacological properties, and, therefore, they are used as vehicles in the synthesis of valuable organic combinations. They show varied biological properties viz. anticancer, anticonvulsant, antimicrobial, anti-inflammatory, neuroprotective, antioxidant activity and so on. This diversity in the biological response makes it a highly prized moiety. Based on literature studies, various synthetic approaches like multicomponent reaction, click reaction, nano-catalysis and green chemistry have been employed to improve their selectivity, purity, product yield and pharmacokinetic activity. In this review article, we have summarized systematic approaches for the synthesis of thiazolidine and its derivatives, along with their pharmacological activity, including advantages of green synthesis, atom economy, cleaner reaction profile and catalyst recovery which will help scientists to probe and stimulate the study of these scaffolds.

Synthesis of thiazolidin-4-ones and thiazinan-4-ones from 1-(2-aminoethyl)pyrrolidine as acetylcholinesterase inhibitors

The present study describes the synthesis of a novel series of thiazolidin-4-one and thiazinan-4-one using 1-(2-aminoethyl)pyrrolidine as amine precursor. All compounds were synthesised by one-pot three component cyclocondensation reaction from the amine, a substituted benzaldehyde and a mercaptocarboxylic acid. The compounds were obtained in moderate to good yields and were identified and characterised by ¹H, ¹³C, 2 D NMR and GC/MS techniques. The compounds also were screened for their in vitro acetylcholinesterase (AChE) activity in hippocampus and cerebral cortex on Wistar rats. The six most potent compounds have been investigated for their cytotoxicity by cell viability assay of astrocyte primary culture, an important cell of central nervous system. We highlighted two compounds (6a and 6k) that had the lowest IC₅₀ in hippocampus (5.20 and 4.46 µM) and cerebral cortex (7.40 and 6.83 µM). These preliminary and important results could be considered a starting point for the development of new AChE inhibitory agents.

Asymmetric synthesis of spirooxindole-fused spirothiazolones via squaramide-catalysed reaction of 3-chlorooxindoles with 5-alkenyl thiazolones

An efficient and practical organocatalyzed asymmetric formal [2 + 1] cycloaddition of 3-chlorooxindoles with 5-alkenyl thiazolones by using hydroquinine-derived squaramide as the catalyst has been developed. Under mild conditions, a broad range of spirooxindole-fused spirothiazolones bearing three adjacent stereogenic centers including two vicinal spiro quaternary chiral centers were obtained in high yields (up to 99% yield) with excellent diastereoselectivities (up to >99 : 1 dr) and enantioselectivities (up to 99% ee).

Protein‑ and growth‑modulatory effects of carcinoma‑associated fibroblasts on breast cancer cells: Role of interleukin‑6

Carcinoma-associated fibroblasts (CAFs) secrete factors that increase the expression and/or activities of proteins in breast cancer cells and induce resistance to anti-estrogens, such as fulvestrant. A major factor is interleukin-6 (IL-6). This study demonstrated that, across estrogen receptor (ER) α-positive and -negative cell lines, recombinant human IL-6 (rhIL-6) mimicked most of the CAF-conditioned medium (CM)-induced changes in protein expression patterns; however, in most cases, it failed to recapitulate CAF-CM-triggered alterations in ERK1/2 and AKT activities. The ability of rhIL-6 to induce fulvestrant resistance was dependent upon the culture conditions. In 3D, but not in 2D cultures, rhIL-6 increased the survival of fulvestrant-treated cells, although not to the same extent as observed with CAF-CM. In 2D cultures, rhIL-6 acted in a pro-apoptotic manner and decreased the expression of ATP-binding cassette transporter G2 (ABCG2). The inhibition of the PI3K/AKT pathway had similar effects on apoptosis and ABCG2 expression, linking the failure of rhIL-6 to induce fulvestrant resistance to its inability to activate the PI3K/AKT pathway. In 3D cultures, both CAF-CM and rhIL-6 acted in an anti-apoptotic manner. These activities are likely independent on the PI3K/AKT pathway and ABCG2. Experiments on ERα-negative breast cancer cells revealed a growth-inhibitory effects of both CAF-CM and rhIL-6, which coincided with a reduction in the c-Myc level. These data suggest that IL-6 plays a role in several effects of CAF-CM, including alterations in protein expression patterns, fulvestrant resistance in 3D cultures and growth inhibition. By contrast, IL-6 is unlikely to be responsible for the CAF-CM-induced activation of the PI3K/AKT pathway and fulvestrant resistance in 2D cultures.

Synthesis, Molecular Docking Analysis, and Carbonic Anhydrase Inhibitory Evaluations of Benzenesulfonamide Derivatives Containing Thiazolidinone

To find novel human carbonic anhydrase (hCA) inhibitors, we synthesized thirteen compounds by combining thiazolidinone with benzenesulfonamide. The result of the X-ray single-crystal diffraction experiment confirmed the configuration of this class of compounds. The enzyme inhibition assays against hCA II and IX showed desirable potency profiles, as effective as the positive controls. The docking studies revealed that compounds (2) and (7) efficiently bound in the active site cavity of hCA IX by forming sufficient interactions with active site residues. The fragment of thiazolidinone played an important role in the binding of the molecules to the active site.