2-Benzoylbenzofuran derivatives possessing piperazine linker as anticancer agents

Novel mandelic acid derivatives containing piperazinyls as potential candidate fungicides against Monilinia fructicola: Design, synthesis and mechanism study

Brown rot of stone fruit, a disease caused by the ascomycete fungus Monilinia fructicola, has caused significant losses to the agricultural industry. In order to explore and discover potential fungicides against M. fructicola, thirty-one novel mandelic acid derivatives containing piperazine moieties were designed and synthesized based on the amide skeleton. Among them, target compound Z31 exhibited obvious in vitro antifungal activity with the EC50 value of 11.8 mg/L, and significant effects for the postharvest pears (79.4 % protective activity and 70.5 % curative activity) at a concentration of 200 mg/L. Antifungal activity for the target compounds was found to be significantly improved by the large steric hindrance of the R1 groups and the electronegative of the piperazines in the molecular structure, according to a three-dimensional quantitative structure-activity relationship (3D-QSAR) analysis. Further mechanism studies have demonstrated that the compound Z31 can disrupt cell membrane integrity, resulting in increased membrane permeability, release of intracellular electrolytes, and affect the normal growth of hyphae. Additional, morphological study also indicated that Z31 may disrupt the integrity of the membrane by inducing generate excess endogenous reactive oxygen species (ROS) and resulting in the peroxidation of cellular lipids, which was further verified by the detection of malondialdehyde (MDA) content. These studies have provided the basis for the creation of novel fungicides to prevent brown rot in stone fruits.

Synthesis and Cytotoxic Activity of Quinazoline-benzofuran Conjugates

AIMS

In order to study on structure-activity relationships of benzofurans.

BACKGROUND

Benzofuran is a kind of natural compound widely existing in nature with pharmacological effects. The development of new anticancer benzofuran derivatives has attracted more and more attention.

METHODS

We have introduced an active quinazoline unit into piperazine-substituted benzofuran, prepared a series of quinazoline-benzofuran compounds, and evaluated cytotoxic activity against a panel of human tumor cell lines by MTT assay.

RESULTS

48 novel quinazoline-substituted benzofuran derivatives have been prepared, and in vitro, cytotoxic activity against five human tumor cell lines was evaluated. The results indicated that some quinazoline-benzofuran conjugates showed selective inhibitory activity against tumor cell lines.

CONCLUSION

We have found that compound 14x displayed excellent cytotoxic activity, which could be considered a potential anticancer agent.

Repurposing Study of 4-Acyl-1-phenylaminocarbonyl-2-substituted-piperazine Derivatives as Potential Anticancer Agents-In Vitro Evaluation against Breast Cancer Cells

Breast cancer is the most common type of cancer in women. Although current treatments can increase patient survival, they are rarely curative when the disease is advanced (metastasis). Therefore, there is an urgent need to develop new cytotoxic drugs with a high selectivity toward cancer cells. Since repurposing approved drugs for cancer therapy has been a successful strategy in recent years, in this study, we screened a library of antiviral piperazine-derived compounds as anticancer agents. The compounds included a piperazine ring and aryl urea functions, which are privileged structures present in several anti-breast cancer drugs. The selective cytotoxic activity of a set of thirty-four 4-acyl-2-substituted piperazine urea derivatives against MCF7 breast cancer cells and MCF 10A normal breast cells was determined. Compounds 31, 32, 35, and 37 showed high selective anticancer activity against breast cancer cells and were also tested against another common type of cancer, non-small cell lung cancer (A549 lung cancer cells versus MRC-5 lung normal cells). Compounds 35 and 37 also showed selectivity against lung cancer cells. These results suggest that compounds 35 and 37 may be promising hit compounds for the development of new anticancer agents.

Optimization and antifungal activity of quinoline derivatives linked to chalcone moiety combined with FLC against Candida albicans

In present work, a series of quinoline derivatives linked to chalcone moiety have been prepared, and their in vitro and in vivo antifungal activities against C. albicans have been evaluated. The results indicated that quinoline combined with fluconazole (FLC) showed good inhibitory activity against C. albicans. Especially, compound PK-10 combined with FLC displayed the best antifungal activity against 14 FLC-resistant C. albicans strains with almost no cytotoxicity. Preliminary mechanistic studies proved that PK-10 combined with FLC could inhibit the hyphae formation of C. albicans, induce the accumulation of reactive oxygen species (ROS), the damage of mitochondrial membrane potential and the decrease of intracellular ATP content, which led to mitochondrial dysfunction. In vivo studies found obvious effects of the co-treatment regimen had obvious effects based on histological analysis, body weight curves, and coefficients of major organs. Therefore, the optimization of quinolone-chalcone derivatives combined with FLC could exert the potent antifungal activity in vitro and in vivo obviously, suggesting them as new agents to treat drug-resistant C. albicans infection.

Anticancer evaluation of benzofuran derivatives linked to dipiperazine moiety

In this work, a series of novel benzofuran derivatives linked to dipiperazine moiety have been prepared, and in vitro anticancer activity against Hela and A549 was investigated. The results demonstrated that benzofuran derivatives exerted potent antitumor effect. Especially, compounds 8c and 8d showed better antitumor activity against A549 (IC50 = 0.12 μM and 0.43 μM). Further mechanism study indicated that compound 8d could significantly induce cell apoptosis in A549 by FACs analysis.

Anticancer therapeutic potential of benzofuran scaffolds

Benzofuran moiety is the main component of many biologically active natural and synthetic heterocycles. These heterocycles have unique therapeutic potentials and are involved in various clinical drugs. The reported results confirmed the extraordinary inhibitory potency of such benzofurans against a panel of human cancer cell lines compared with a wide array of reference anticancer drugs. Several publications about the anticancer potencies of benzofuran-based heterocycles were encountered. The recent developments of anticancer activities of both natural and synthetic benzofuran scaffolds during 2019-2022 are thoroughly covered. Many of the described benzofurans are promising candidates for development as anticancer agents based on their outstanding inhibitory potency against a panel of human cancer cells compared with reference anticancer drugs. These findings encourage medicinal chemists to explore new areas to improve human health and reduce suffering.

Aminobenzofuran-containing analogues of proximicins exhibit higher antiproliferative activity against human UG-87 glioblastoma cells compared to temozolomide

A new series of proximicin analogues containing a benzofuran moiety as the replacement of the di-furan scaffold of the parent compound were synthesised and evaluated for their anti-proliferative activities against human glioblastoma cells U-87 MG. Proximicins A, B, and C are secondary metabolites produced by Verrucosispora Fiedleri MG-37, a Gram-positive actinomycete isolated from deep-sea sediment. Proximicins exhibit significant cytotoxic and apoptotic effects in a number of tumour cell lines, although further investigations on these natural products biological activity are hampered by the challenging synthesis of their constitutive di-furan unit. Therefore, the easily-synthesisable benzofuran ring was elected as a replacement of the di-furan platform, and a library of proximicin analogues was prepared in which different substituents were introduced at both the N-terminus and C-terminus of the benzofuran core unit. The novel compounds were tested against U-87 MG, as it was previously found that proximicins targeted this cancerous cell line, and the human healthy cell line WI-38. Temozolomide, the chemotherapeutic agent of choice for the treatment of glioblastoma, was used as a control. Analysis of growth inhibitory concentration values revealed that a number of furan-benzofuran-containing proximicin analogues, including 23(16) (IC_{50 U-87 MG} = 6.54 μg mL^-1) exhibited higher antiproliferative activity against glioblastoma cells compared to both proximicins A-C and temozolomide (IC_{50 U-87 MG} = 29.19 μg mL^-1) in U-87 MG.

Structure-Activity Relationship of Benzofuran Derivatives with Potential Anticancer Activity

Simple Summary

Cancer is the leading cause of death worldwide and responsible for killing approximately 10 million people per year. Fused heterocyclic ring systems such as benzofuran have emerged as important scaffolds with many biological properties. Furthermore, derivatives of benzofurans demonstrate a wide range of biological and pharmacological activities, including anticancer properties. The main aim of this review is to highlight and discuss the contribution of benzofuran derivatives as anticancer agents by considering and discussing the chemical structure of 20 different compounds. Evaluating the chemical structure of these compounds will guide future medicinal chemists in designing new drugs for cancer therapy that might give excellent results in in vivo/in vitro applications.

Abstract

Benzofuran is a heterocyclic compound found naturally in plants and it can also be obtained through synthetic reactions. Multiple physicochemical characteristics and versatile features distinguish benzofuran, and its chemical structure is composed of fused benzene and furan rings. Benzofuran derivatives are essential compounds that hold vital biological activities to design novel therapies with enhanced efficacy compared to conventional treatments. Therefore, medicinal chemists used its core to synthesize new derivatives that can be applied to a variety of disorders. Benzofuran exhibited potential effectiveness in chronic diseases such as hypertension, neurodegenerative and oxidative conditions, and dyslipidemia. In acute infections, benzofuran revealed anti-infective properties against microorganisms like viruses, bacteria, and parasites. In recent years, the complex nature and the number of acquired or resistant cancer cases have been largely increasing. Benzofuran derivatives revealed potential anticancer activity with lower incidence or severity of adverse events normally encountered during chemotherapeutic treatments. This review discusses the structure–activity relationship (SAR) of several benzofuran derivatives in order to elucidate the possible substitution alternatives and structural requirements for a highly potent and selective anticancer activity.

Discovery of heterocyclic substituted dihydropyrazoles as potent anticancer agents

In this work, a series of novel heterocyclic substituted dihydropyrazole derivatives have been prepared, and in vitro anticancer activity against a panel of human tumor cell lines by SRB were evaluated. The results indicated that piperazine substituted dihydropyrazole derivatives exhibited superior anticancer activity than that of other compounds. Especially, compounds 4g, 4h, 4l, 4m, 4o, 6g, 6j and 6l showed potent antitumor activity. Further mechanism study demonstrated that compound 4o could induce G2/M arrest in HCC1806 cell and p21 accumulation significantly.

Novel ginsenoside derivatives have shown their effects on PC-3 cells by inducing G1-phase arrest and reactive oxygen species-mediate cell apoptosis

In this study, piperazine groups were introduced into ginsenoside to enhance its ability to induce Reactive Oxygen Species (ROS) production and apoptosis in cancer cells. In total, 27 ginsenoside piperazine derivatives were synthesized and tested for their anti-proliferative activity in cancer cell lines by MTT assay. The results showed that compounds 4a, 4g, 4f, 4i, 5g, 5i, 6a, 6g, 6f and 6i had significant inhibitory effects on cancer cell growth. Compound 6g showed the strongest anti-proliferative effect on PC-3 cells with an IC₅₀ of 1.98 ± 0.34 μM. Compound 6g could also induce G1-phase arrest and apoptosis in PC-3 cells, with apoptosis rates of 8.1%, 41% and 56.1% observed at 5, 10 and 20 μM, respectively. Compound 6g also significantly enhanced the intracellular fluorescence of ROS sensitive substrates, with a fluorescence intensity ratio of 23.1% observed in treated cells, indicative of ROS production. Following N-acetylcysteine treatment, apoptotic rates of the cancer cell lines decreased from 38.9% to 7.3%, and the expression of Cl-PARP, Cl-Caspase-3 and Cl-Caspase-9 also decreased, confirming that compound 6g induced apoptosis through ROS induction. Compound 6g also stimulated the translocation of Bax from the cytoplasm to the mitochondria, which enhanced Cytochrome C (Cyt C) release, and increased the expression of the apoptotic markers Cl-PARP, Cl-Caspase-3, and Cl-Caspase-9 in PC-3 cells. Taken together, these data reveal the anti-cancer effects of compound 6g that enhance ROS production, and then induce apoptosis through mitochondrial pathway.

Synthesis of imidazole-pyrazole conjugates bearing aryl spacer and exploring their enzyme inhibition potentials

Developing improved enzyme inhibitors is an effective therapy to counter various diseases. Aiming to build up biologically active templates, a new series of bis-diazoles conjugated with an aryl linker was designed and prepared through a convenient synthetic approach. Synthesized derivatives 6(a-m), having different substitutions at the 2^nd position of the imidazole nucleus, depict the scope of present study. These compounds were characterized through spectroscopic methods and further examined for their in vitro enzyme inhibitory potentials against two selected enzymes: α-glucosidase and lipoxygenase (LOX). Overall, this series was found to be effective against α-glucosidase and moderately active against LOX enzyme. Compound 6k was the most potent α-glucosidase inhibitor with IC₅₀ = 54.25 ± 0.67 µM as compared to reference drug acarbose (IC₅₀ = 375.82 ± 1.76 µM). The docked conformation revealed the involvement of substituent's heteroatoms with amino acid residue Gly280 through hydrogen bonding. The most active LOX inhibitor was 6a with IC₅₀ = 41.75 ± 0.04 µM as compared to standard baicalein (IC₅₀ = 22.4 ± 1.3 µM). Docking model of 6a suggested the strong interaction of imidazole's nitrogen with iron atom of the active pocket of enzyme. Other features like lipophilicity, bulkiness of compounds, pi-pi interactions and/or pi-alkyl interactions also affected the inhibiting potentials of all prepared scaffolds.

Diversity-oriented generation and biological evaluation of new chemical scaffolds bearing a 2,2-dimethyl-2H-chromene unit: Discovery of novel potent ANO1 inhibitors

Chemical territory bearing a 2,2-dimethyl-2H-chromene motif was expanded by utilizing an o-hydroxy aldehyde group of 5-hydroxy-2,2-dimethyl-2H-chromene-6-carbaldehyde as a synthetic handle to install distinctive morphology and functionality of each scaffold. Cell based assays and in silico docking analysis led us to discover that these new compounds exhibit inhibitory effect on anoctamin1 (ANO1). ANO1 is amplified and highly expressed in various carcinomas including prostate cancer, esophageal cancer, breast cancer, and pancreatic cancer. Biological assays revealed that (E)-1-(7,7-dimethyl-7H-furo[2,3-f]chromen-2-yl)-3-(1H-pyrrol-2-yl)prop-2-en-1-one (3n, Ani-FCC) is a novel, potent and selective ANO1 inhibitor with an IC₅₀ value of 1.23 μM. 3n showed 144 times stronger activity on ANO1 inhibition than ANO2 inhibition and did not alter the chloride channel activity of CFTR and the intracellular calcium signaling. Notably, 3n strongly decreased cell viability of PC-3 and FaDu cells expressing high levels of ANO1 with a decrease in ANO1 protein levels. In addition, 3n significantly enhanced apoptosis via activation of caspase 3 and cleavage of PARP in PC-3 and FaDu cells. This study shows that a novel ANO1 inhibitor, 3n, can be a potential candidate for the treatment of cancers overexpressing ANO1, such as prostate cancer and esophageal cancer.

Synthesis and Biological Evaluation of Heterocyclic Substituted Bis(indolyl)methanes

Background:

Bis(indolyl)methane derivatives are widely found in nature with a broad range of biological and pharmacological activities. The development of techniques for the synthesis and functionalization of bis(indolyl)methanes have attracted more and more attention in recent years.

Objective:

To study the synthesis and biological activity of heterocyclic substituted bis(indolyl)methanes.

Materials and Methods:

A series of heterocyclic substituted bis(indolyl)methanes (3a-3p) have been prepared by condensation reaction of indole and heterocyclic aldehydes catalyzed by boron trifluoride etherate with high yields. Preliminary in vitro anti-inflammatory in lipopolysaccharide (LPS)-stimulated RAW-264.7 macrophages and cytotoxic activity against human tumor cell lines (A549, Hela and SGC7901) by MTT assay were tested.

Results:

The result indicated that heterocyclic substituted bis(indolyl)methanes showed good antiinflammatory and selective cytotoxic activity. Especially, compounds 3o, 3p and 3q displayed similar inhibitory effect on the generation of NO to positive control dexamethasone, and compound 3q displayed similar selective cytotoxic activity to 5-FU.

Conclusion:

Heterocyclic substituted bis(indolyl)methanes may be used as potential anti-inflammatory and anticancer leads.

Enhancing the Corrosion Protection of AA2024-T3 Alloy by Surface Treatments Based on Piperazine-Modified Hybrid Sol–Gel Films

The aim of this study was to develop new chrome-free surface pretreatments for AA2024-T3 aluminum alloy. These pretreatments were based on hybrid organic–inorganic sol–gel thin films prepared from mixtures of γ-methacryloxypropyltrimethoxysilane (MAPTMS) and tetramethylorthosilicate (TMOS). Different MAPTMS/TMOS molar ratios were used for optimizing the physical–chemical characteristics of the sol–gel films. The formulation of a set of these sols was modified by incorporating piperazine (1,4-diazacyclohexane) as a corrosion inhibitor. The resulting sol–gel films were characterized by using Fourier transform infrared spectroscopy (FTIR), liquid-state 29Si nuclear magnetic resonance spectroscopy (29Si-NMR) and viscosity measurements. The corrosion performance of the sol–gel films was analyzed by using electrochemical impedance spectroscopy (EIS) and local electrochemical impedance mapping (LEIM). The characterization techniques indicated that piperazine behaved as a catalyst for the condensation reaction during the formation of the MAPTMS/TMOS organopolysiloxane network and produces an increase of the crosslinking degree of the sol–gel films. EIS and LEIM results showed that piperazine is an effective corrosion inhibitor, which can be used to enhance the active corrosion protection performance of sol–gel films.