Synthesis and bio-evaluation of indole-chalcone based benzopyrans as promising antiligase and antiproliferative agents

Synergy between human DNA ligase I and topoisomerase 1 unveils new therapeutic strategy for the management of colorectal cancer

DNA topoisomerase 1 (Topo 1) is a pivotal player in various DNA processes, including replication, repair, and transcription. It serves as a target for anticancer drugs like camptothecin and its derivatives (Topotecan and SN-38/Irinotecan). However, the emergence of drug resistance and the associated adverse effects, such as alopecia, anemia, dyspnea, fever, chills, and painful or difficult urination, pose significant challenges in Topo 1-targeted therapy, necessitating urgent attention. Human DNA Ligase 1 (hLig I), recognized primarily for its role in DNA replication and repair of DNA breaks, intriguingly exhibits a DNA relaxation activity akin to Topo 1. This raised the hypothesis that hLig I might compensate for Topo 1 inhibition, contributing to resistance against Topo 1 inhibitors. To explore this hypothesis, we assessed the efficacy of hLig I inhibition alone and in combination with Topo 1 in cancer cells. As anticipated, the overexpression of hLig I was observed after Topo 1 inhibition in colorectal cancer cells, affirming our hypothesis. Previously identified as an inhibitor of hLig I's DNA relaxation activity, compound 27 (C 27), when combined with Topotecan, demonstrated a synergistic antiproliferative effect on colorectal cancer cells. Notably, cells with downregulated hLig I (via siRNA, inhibitors, or genetic manipulation) exhibited significantly heightened sensitivity to Topotecan. This observation strongly supports the concept that hLig I contribute to resistance against clinically relevant Topo 1 inhibitors in colorectal cancers. In conclusion, our findings offer evidence for the synergistic impact of combining hLig I inhibitors with Topotecan in the treatment of colorectal cancers, providing a promising strategy to overcome resistance to Topo 1 inhibitors.

Application of Chalcone in the Structural Modification of Natural Products: An Overview

Natural products frequently display a range of biological activities, yet many exhibit only moderate efficacy during initial evaluations. Often, these natural substances necessitate structural alterations to yield promising lead compounds. Chalcones, characterized by their β-unsaturated carbonyl aromatic ketone structure, are prevalent in plant life and serve as fundamental scaffolds for the biosynthetic precursors of flavonoids and isoflavones. Due to their straightforward synthesis and extensive spectrum of biological effects, chalcones have found extensive application in medicinal chemistry. Chalcone analogs have demonstrated significant potential for drug discovery and development, as structural modifications can both amplify pharmacological efficacy and effectively mitigate toxic side effects. This paper endeavors to delve into the applications of chalcones in the structural modification of natural products, providing a theoretical foundation for future endeavors in derivatization and drug development. The full paper is organized into categories based on the biological activities of the derivatives, including anti-dyslipidemic, antibacterial, antimalarial, anti-inflammatory, anticancer, anti-Alzheimer, and α-glucosidase inhibitory activities.

The Intestinal Barrier Protective Effect of Indole Aldehyde Derivatives on Acute Toxoplasma gondii Infection

Toxoplasmosis, a zoonotic infection caused by Toxoplasma gondii (T. gondii), poses a significant risk to human health and public safety. Despite the availability of clinical treatments, none effectively mitigate the intestinal barrier damage, which is the primary defense against T. gondii invasion. This study introduced aldehyde groups into the indole scaffold of a peptide-like structure to investigate the protective effects of these indole aldehyde derivatives on the intestinal barrier in mice with acute T. gondii infection. This approach leveraged the propensity of peptides and aldehyde groups to form hydrogen bonds. We synthesized a range of indole derivatives using the Vilsmeier-Haack reaction and evaluated their intestinal barrier protective effects both in vitro and in vivo. Our findings revealed that indole derivatives A1 (1-Formyl-1H-indole-3-acetonitrile), A3 (Indole-3-carboxaldehyde), A5 (2-Chloro-1H-indole-3-carboxaldehyde), A8 (1-Methyl-indole-3-carboxaldehyde), and A9 (1-Methyl-2-phenyl-1H-indole-3-carboxaldehyde) demonstrated a higher selectivity index compared to the positive control, spiramycin. These derivatives enhanced gastrointestinal motility, increased glutathione (GSH) levels in the small intestine, and reduced malondialdehyde (MDA) and nitric oxide (NO) levels in the small intestine tissue and diamine oxidase (DAO) and NO levels in the serum of infected mice. Notably, A3 exhibited comparable anti-T. gondii tachyzoites activity in the peritoneal cavity. Molecular docking studies indicated that the aldehyde group on the indole scaffold not only formed a hydrogen bond with NTPase-II but also interacted with TgCDPK1 through hydrogen bonding. Among the derivatives, A3 showed promising intestinal barrier protective effects in mice with acute T. gondii infection. This research suggests that indole derivatives could serve as a potential therapeutic strategy for intestinal diseases induced by T. gondii, offering a novel direction for treating intestinal barrier damage and providing valuable insights for the chemical modification of drugs targeting T. gondii. Furthermore, it contributes to the advancement of therapeutic approaches for toxoplasmosis.

Synthesis, molecular modelling and evaluation of larvicidal efficacy of annulated Benzo[h]chromenes against Culex pipiens L. Larvae

A new series of substituted benzo[h]chromene, benzochromenopyrimidine, and benzochromenotriazolopyrimidine derivatives were synthesized via chemical transformations of iminonitrile, ethoxymethylene amino, and cyanomethylene functionalities. The chemical structures of the synthesized compounds were assured by spectroscopic data and elemental analysis. The larvicidal efficacy of these compounds against Culex pipiens L. larvae was investigated, revealing potent insecticidal activity, particularly for compounds 6, 10, and 16, exceeding that of the standard insecticide chlorpyrifos. The mode of action of these compounds was explored through molecular docking studies, indicating their potential as acetylcholine esterase (AChE) inhibitors and nicotinic acetylcholine receptors (nAChR) blockers. The structure-activity relationship analysis highlighted the influence of substituents and fused heterocyclic rings on larvicidal potency. These findings suggest that the synthesized compounds hold promise as potential candidates for developing novel and effective mosquito control agents.

Discovery of benzochromene derivatives first example with dual cytotoxic activity against the resistant cancer cell MCF-7/ADR and inhibitory effect of the P-glycoprotein expression levels

A series of 1H-benzo[f]chromene moieties (4a-z) were synthesised under Ultrasonic irradiation and confirmed with spectral analyses. Derivative 4i solely possessed an X-ray single crystal. The anti-proliferative efficacy of the desired molecules has been explored against three cancer cells: MCF-7, HCT-116, and HepG-2 with the cytotoxically active derivatives screened against MCF-7/ADR and normal cells HFL-1 and WI-38. Furthermore, compounds 4b-d, 4k, 4n, 4q, and 4w, which possessed good potency against MCF-7/ADR, were tested as permeability glycoprotein (P-glycoprotein [P-gp]) expression inhibitors. The attained data confirmed that 4b-d, 4q, and 4w exhibited strong expression inhibition against the P-gp alongside its cytotoxic effect on MCF-7/ADR. The western blot results and Rho123 accumulation assays showed that compounds 4b-d, 4q, and 4w effectively inhibited the P-gp expression and efflux function. Meanwhile, 4b-d, 4q, and 4w induced apoptosis and accumulation of the treated MCF-7/ADR cells in the G1 phase and 4k and 4n in the S phase of the cell cycle.

Chalcone: A Promising Bioactive Scaffold in Medicinal Chemistry

Chalcones are a class of privileged scaffolds with high medicinal significance due to the presence of an α,β-unsaturated ketone functionality. Numerous functional modifications of chalcones have been reported, along with their pharmacological behavior. The present review aims to summarize the structures from natural sources, synthesis methods, biological characteristics against infectious and non-infectious diseases, and uses of chalcones over the past decade, and their structure-activity relationship studies are detailed in depth. This critical review provides guidelines for the future design and synthesis of various chalcones. In addition, this could be highly supportive for medicinal chemists to develop more promising candidates for various infectious and non-infectious diseases.

Cu(II)-Catalysed Hydrocarboxylation of Imines Utilizing CO2 to Synthesize α-Unsaturated Aminocarboxylic Acids

Here, we report the Cu(II)-photocatalysed hydrocarboxylation of imines (C=N) from a series of synthesized Schiff Base derivatives, namely (E)-1-(4-((4-methylbenzylidene)amino)phenyl)ethanone, (E)-1-(3-((5-bromo-2-hydroxybenzylidene)amino)phenyl)ethanone, (E)-4-((5-bromo-2-hydroxybenzylidene)amino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one, and (E)-1,5-dimethyl-4-((4-methylbenzylidene)amino)-2-phenyl-1H-pyrazol-3(2H)-one, with carbon dioxide (CO₂) to generate disubstituted amino acids. Under mild conditions (atmospheric pressure of CO₂, room temperature, and 30 W Blue LED light), good to excellent yields confirming the formation of substituted amino acid unsaturated acid derivatives were obtained. Single crystal X-ray diffraction (SC-XRD) and UV-Vis diffuse reflectance spectroscopy (UV-Vis-DRS) confirmed the square pyramidal geometry of the Cu(II) photocatalyst. Docking and DFT calculations of the substituted amino acid unsaturated acid derivatives showed their potential as antimicrobial molecules.

Synthesis, Anticancer Assessment, and Molecular Docking of Novel Chalcone-Thienopyrimidine Derivatives in HepG2 and MCF-7 Cell Lines

Heterocycles containing thienopyrimidine moieties have attracted attention due to their interesting biological and pharmacological activities. In this research article, we reported the synthesis of a series of new hybrid molecules through merging the structural features of chalcones and pyridothienopyrimidinones. Our results indicated that the synthesis of chalcone-thienopyrimidine derivatives from the corresponding thienopyrimidine and chalcones proceeded in a relatively short reaction time with good yields and high purity. Most of these novel compounds exhibited moderate to robust cytotoxicity against HepG2 and MCF-7 cancer cells similar to that of 5-fluorouracil (5-FU). The results indicated that IC₅₀ of the two compounds (3b and 3g) showed more potent anticancer activities against HepG2 and MCF-7 than 5-FU. An MTT assay and flow cytometry showed that only 3b and 3g had anticancer activity and antiproliferative activities at the G1 phase against MCF-7 cells, while six compounds (3a-e and 3g) had cytotoxicity and cell cycle arrest at different phases against HepG2 cells. Their cytotoxicity was achieved through downregulation of Bcl-2 and upregulation of Bax, caspase-3, and caspase-9. Although all tested compounds increased oxidative stress via increment of MDA levels and decrement of glutathione reductase (GR) activities compared to control, the 3a, 3b, and 3g in HepG2 and 3b and 3g in MCF-7 achieved the target results. Moreover, there was a positive correlation between cytotoxic efficacy of the compound and apoptosis in both HepG2 (R ² = 0.531; P = 0.001) and MCF-7 (R ² = 0.219; P = 0.349) cell lines. The results of molecular docking analysis of 3a-g into the binding groove of Bcl-2 revealed relatively moderate binding free energies compared to the selective Bcl-2 inhibitor, DRO. Like venetoclax, compounds 3a-g showed 2 violations from Lipinski's rule. However, the results of the ADME study also revealed higher drug-likeness scores for compounds 3a-g than for venetoclax. In conclusion, the tested newly synthesized chalcone-pyridothienopyrimidinone derivatives showed promising antiproliferative and apoptotic effects. Mechanistically, the compounds increased ROS production with concomitant cell cycle arrest and apoptosis. Therefore, regulation of the cell cycle and apoptosis are possible targets for anticancer therapy. The tested compounds could be potent anticancer agents to be tested in future clinical trials after extensive pharmacodynamic, pharmacokinetic, and toxicity profile investigations.

Synthesis, Structural Characterizations, and Quantum Chemical Investigations on 1-(3-Methoxy-phenyl)-3-naphthalen-1-yl-propenone

In the present study, 1-(3-methoxy-phenyl)-3-naphthalen-1-yl-propenone (MPNP) is synthesized and characterized by several experimental techniques such as Fourier transform-infrared spectroscopy (FT-IR), FT-Raman, NMR and UV-vis spectral methods. The similar techniques are also investigated by the computational method using Gaussian software. The density functional theory (DFT) method is used to obtain the optimized structure using the B3LYP/6-311++G(d,p) basis set. This optimization procedure of the molecule gives the minimum energy confirmation of the structure. The computed geometrical parameters are compared with experimental data. The experimental FT-IR and FT-Raman spectra of MPNP are obtained in the regions 4000-400 and 4000-50 cm-1 respectively. The detailed vibrational assignments of the molecule are obtained with the support of potential energy distribution. The theoretical NMR (1H and 13C) analysis is conducted by the GIAO method for its structural characterization and compared with experimental chemical shifts. The experimental UV-vis spectrum is obtained in the dimethyl sulfoxide solvent and compared with the theoretically computed spectrum by the time-dependent DFT method. In addition to these studies, other analyses such as nonlinear optical, natural bonds orbital, frontier molecular orbital, molecular electrostatic potential, and NCI have been conducted to understand the nature of the molecule. The title molecule is docked and also the drug-likeness, ADMET studies were carried out. The RBD domain bound to the ACE2 receptor during the fusion makes spike glycoprotein an elusive therapeutic target in SARS-CoV-2 infection.

Synthesis and biological evaluation of chalcone-polyamine conjugates as novel vectorized agents in colorectal and prostate cancer chemotherapy

The aim of this study was to synthesize chalcone-polyamine conjugates in order to enhance bioavailability and selectivity of chalcone core towards cancer cells, using polyamine-based vectors. Indeed, it is well-known that polyamine transport system is upregulated in tumor cells. 3',4,4',5'-tetramethoxychalcone was selected as parent chalcone since it was found to be an efficient anti-proliferative agent on various cancer cells. A series of five chalcone-polyamine conjugates was obtained using the 4-bromopropyloxy-3',4',5'-trimethoxychalcone as a key intermediate. Chalcone core and polyamine tails were fused through an amine bond. These conjugates were found to possess a marked in vitro antiproliferative effect against colorectal (HT-29 and HCT-116) and prostate cancer (PC-3 and DU-145) cell lines. The most active conjugate (compound 8b) was then chosen for further biological evaluations to elucidate mechanisms responsible for its antiproliferative activity. Investigations on cell cycle distribution revealed that this conjugate can prevent the proliferation of human colorectal and prostate cancer cells by blocking the cell cycle at the G1 and G2 phase, respectively. Flow cytometry analysis revealed a sub-G1 peak, characteristic of apoptotic cell population and our inquiries highlighted apoptosis induction at early and later stages through several pro-apoptotic markers. Therefore, this chalcone-N1-spermidine conjugate could be considered as a promising agent for colon and prostatic cancer adjuvant therapy.

Coumarin hybrid derivatives as promising leads to treat tuberculosis: Recent developments and critical aspects of structural design to exhibit anti-tubercular activity

Tuberculosis (TB) is a highly contagious airborne disease with nearly 25% of the world's population infected with it. Challenges such as multi drug resistant TB (MDR-TB), extensive drug resistant TB (XDR-TB) and in rare cases totally drug resistant TB (TDR-TB) emphasizes the critical and urgent need in developing novel TB drugs. Moreover, the prolonged and multi drug treatment regime suffers a major drawback due to high toxicity and vulnerability in TB patients. This calls for intensified research efforts in identifying novel molecular scaffolds which can combat these issues with minimal side effects. In this pursuit, researchers have screened many bio-active molecules among which coumarin have been identified as promising candidates for TB drug discovery and development. Coumarins are naturally occurring compounds known for their low toxicity and varied biological activity. The biological spectrum of coumarin has intrigued medicinal researchers to investigate coumarin scaffolds for their relevance as anti-TB drugs. In this review we focus on the recent developments of coumarin and its critical aspects of structural design required to exhibit anti-tubercular (anti-TB) activity. The information provided will help medicinal chemists to design and identify newer molecular analogs for TB treatment and also broadens the scope of exploring future generation potent yet safer coumarin based anti-TB agents.

Novel indole-thiazole and indole-thiazolidinone derivatives as DNA groove binders

In this study, we report the synthesis of eight novel indole-thiazole and indole-thiazolidinone derivatives, as well as their ability to interact with DNA, analysed through the UV-vis absorption, fluorescence, circular dichroism (CD), viscosity techniques and molecular docking. The ctDNA interaction analysis demonstrated different spectroscopic effects and the affinity constants (Kb) calculated by the UV-vis absorption method were between 2.08 × 10⁵ and 6.99 × 10⁶ M^-1, whereas in the fluorescence suppression constants (Ksv) ranged between 0.38 and 0.77 × 10⁴ M^-1 and 0.60-7.59 × 10⁴ M^-1 using Ethidium Bromide (EB) and 4',6-Diamidino-2-phenylindole (DAPI) as fluorescent probes, respectively. Most derivatives did not alter significantly the secondary structure of the ctDNA according to the CD results. None of the compounds was able to change the relative viscosity of the ctDNA. These results prove that compounds interact with ctDNA via groove binding, which was confirmed by A-T rich oligonucleotide sequence assay with compound JF-252, suggesting the importance of both the phenyl ring coupled to C-4 thiazole ring and the bromo-unsubstituted indole nucleus.

Chalcone hybrids as potential anticancer agents: Current development, mechanism of action, and structure-activity relationship

The continuous emergency of drug-resistant cancers and the low specificity of anticancer agents have been the major challenges in the control and treatment of cancer, making an urgent need to develop novel anticancer agents with high efficacy. Chalcones, precursors of flavonoids and isoflavonoids, exhibit structural heterogeneity and can act on various drug targets. Chalcones which demonstrated potential in vitro and in vivo activity against both drug-susceptible and drug-resistant cancers, are useful templates for the development of novel anticancer agents. Hybridization of chalcone moiety with other anticancer pharmacophores could provide the hybrids which have the potential to overcome drug resistance and improve the specificity, so it represents a promising strategy to develop novel anticancer agents. This review emphasizes the development, the mechanisms of action as well as structure-activity relationships of chalcone hybrids with potential therapeutic application for many cancers in recent 10 years.

Recent Development in Indole Derivatives as Anticancer Agents for Breast Cancer

BACKGROUND

Breast Cancer (BC) is the second most common cause of cancer related deaths in women. Due to severe side effects and multidrug resistance, current therapies like hormonal therapy, surgery, radiotherapy and chemotherapy become ineffective. Also, the existing drugs for BC treatment are associated with several drawbacks such as poor oral bioavailability, non-selectivity and poor pharmacodynamics properties. Therefore, there is an urgent need for the development of more effective and safer anti BC agents.

OBJECTIVE

This article explored in detail the possibilities of indole-based heterocyclic compounds as anticancer agents with breast cancer as their major target.

METHODS

Recent literature related to indole derivatives endowed with encouraging anti BC potential is reviewed. With special focus on BC, this review offers a detailed account of multiple mechanisms of action of various indole derivatives: aromatase inhibitor, tubulin inhibitor, microtubule inhibitor, targeting estrogen receptor, DNA-binding mechanism, induction of apoptosis, inhibition of PI3K/AkT/NFkB/mTOR, and HDAC inhibitors, by which these derivatives have shown promising anticancer potential.

RESULTS

Exhaustive literature survey indicated that indole derivatives are associated with properties of inducing apoptosis and disturbing tubulin assembly. Indoles are also associated with the inhibition of NFkB/mTOR/PI3K/AkT and regulation of estrogen-mediated activity. Furthermore, indole derivatives have been found to modulate critical targets such as topoisomerase and HDAC. These derivatives have shown significant activity against breast cancer cells.

CONCLUSION

In BC, indole derivatives seem to be quite competent and act through various mechanisms that are well established in case of BC. This review has shown that indole derivatives can further be explored for the betterment of BC chemotherapy. A lot of potential is still hidden which demands to be discovered for upgrading BC chemotherapy.

Synthesis of Biologically Active Molecules through Multicomponent Reactions

Focusing on the literature progress since 2002, the present review explores the highly significant role that multicomponent reactions (MCRs) have played as a very important tool for expedite synthesis of a vast number of organic molecules, but also, highlights the fact that many of such molecules are biologically active or at least have been submitted to any biological screen. The selected papers covered in this review must meet two mandatory requirements: (1) the reported products should be obtained via a multicomponent reaction; (2) the reported products should be biologically actives or at least tested for any biological property. Given the diversity of synthetic approaches utilized in MCRs, the highly diverse nature of the biological activities evaluated for the synthesized compounds, and considering their huge structural variability, much of the reported data are organized into concise schemes and tables to facilitate comparison, and to underscore the key points of this review.

Design, synthesis, docking and biological evaluation of chalcones as promising antidiabetic agents

Diabetes mellitus (DM) is a serious chronic metabolic disorder which occurs due to dysfunction of insulin and therapeutic approaches are poor. It is an under estimation that 387 million people currently suffering globally with diabetic and more than 592 million people may be affected by 2030. It makes an urgent necessity to discover novel drugs to control amplified diabetic populations. In this study, amino chalcones (3a-j) were synthesized and hydroxy chalcones (3g-j) were isolated from natural source such as Sophora interrupta, Clerodendrum phlomidis and Andrographis macrobotrys. Structural elucidation was carried out using Mass, ¹H and ¹³C NMR Spectra. In vivo studies were carried out with alloxan induced diabetic rats (100 mg/kg) which reveals compounds 3c, 3a and 3h have significant antidiabetic efficacy with decreased blood glucose levels in the diabetic rats while compared with control rats. Besides, docking studies with aldose reductase, dipeptidyl peptidase, PPAR and glucosidase were monitored which accomplishes that the compounds 3c, 3i, 3a and 3d have eloquent binding affinity (kcal/mol) with aldose reductase, besides the chalcones 3c, 3b, 3d, 3e and 3i were also showed inhibition with DPP-IV, PPAR-α and α-glucosidase. Also, these compounds explicated distinct interactions i.e., π-π, π-cationic, polar, electrostatic and hydrophobic bonds were observed with key residues of binding pockets. Bioavailability is disclosed with Lipinski rule of five and the design pharmacokinetic as well as pharmacodynamic properties are reliable. Therefore, chalcones were implied as antidiabetic leads for in further studies and could be worthwhile for the development of new classes of effective antidiabetic agents.

Recent advances in the targeting of human DNA ligase I as a potential new strategy for cancer treatment

The emergence of drug resistance, coupled with the issue of low tumor selectivity and toxicity is a major pitfall in cancer chemotherapy. It has necessitated the urgent need for the discovery of less toxic and more potent new anti-cancer pharmaceuticals, which target the interactive mechanisms involved in division and metastasis of cancer cells. Human DNA ligase I (hligI) plays an important role in DNA replication by linking Okazaki fragments on the lagging strand of DNA, and also participates in DNA damage repair processes. Dysregulation of the functioning of such ligases can severely impact DNA replication and repair pathways events that are generally targeted in cancer treatment. Although, several human DNA ligase inhibitors have been reported in the literature but unfortunately not a single inhibitor is currently being used in cancer chemotherapy. Results of pre-clinical studies also support the fact that human DNA ligases are an attractive target for the development of new anticancer agents which work by the selective inhibition of rapidly proliferating cancer cells. In this manuscript, we discuss, in brief, the structure, synthesis, structure-activity-relationship (SAR) and anticancer activity of recently reported hLigI inhibitors.

Novel hybrids derived from aspirin and chalcones potently suppress colorectal cancer in vitro and in vivo

Colorectal cancer (CRC) remains the fourth leading cause of cancer deaths around the world despite the availability of many approved small molecules for treatment. The issues lie in the potency, selectivity and targeting of these compounds. Therefore, new strategies and targets are needed to optimize and develop novel treatments for CRC. Here, a group of novel hybrids derived from aspirin and chalcones were designed and synthesized based on recent reports of their individual benefits to CRC targeting and selectivity. The most active compound 7h inhibited proliferation of CRC cell lines with better potency compared to 5-fluorouracil, a currently used therapeutic agent for CRC. Importantly, 7h had 8-fold less inhibitory activity against non-cancer CCD841 cells. In addition, 7h inhibited CRC growth via the inhibition of the cell cycle in the G1 phase. Furthermore, 7h induced apoptosis by activating caspase 3 and PARP cleavage, as well as increasing ROS in CRC cells. Finally, 7h significantly retarded the CRC cell growth in a mouse xenograft model. These findings suggest that 7h may have potential to treat CRC.