Synthesis, in vitro and in vivo antitumor activity of scopoletin-cinnamic acid hybrids

Nano encapsulated polymeric Scopoletin suppresses the progression of colorectal cancer by regulating cytokines and inflammatory mediators in AOM/DSS murine model

Scopoletin (6-methoxy-7-hydroxycoumarin) belongs to the family of coumarins with numerous pharmacological benefits. The present study deals with examining the efficacy of Nanoencapsulated polymeric Scopoletin (NEP-Sc) in murine colon cancer model. Male Balb/c mice were supplemented with NEP-Sc (2.5 and 5 mg/kg b.w.) and 5-fluorouracil (25 mg/kg b.w.) for 10 days consecutively post-induction of colon cancer. Colon polyps and morphology were assessed using a macroscopical inspection, and their score establishes the ameliorative effect of NEP-Sc. Body weight, diarrhoea score, and spleen weight were also measured. The antioxidant status of the mucosal levels of glutathione (GSH), superoxide dismutase (SOD), malondialdehyde (LPO) and nitric oxide (NO) were evaluated. The β-catenin and Ki-67 levels were analyzed through immunohistochemistry analysis to assess the inflammatory response. ELISA-based analysis was used to measure IL-4, IL-6, IL-10, TNF-alpha, IFN-gamma, and VEGF levels. All the aforementioned parameters were mitigated in AOM/DSS-triggered colon cancer in mice treated with NEP-Sc. Nanoencapsulated polymeric Scopoletin offered protection against AOM/DSS-induced colon cancer in mice. To sum up, our research findings suggest that NEP-Sc may act as a promising candidate for treating colon-associated cancer.

An overview of phenylsulfonylfuroxan-based nitric oxide donors for cancer treatment

Nitric oxide (NO) is a gaseous molecule integral to numerous physiological processes, including tumor modulation, cardiovascular regulation, and systemic physiological functions. Its dual role in promoting and inhibiting tumor growth makes it a focal point of contemporary oncological research. Phenylsulfonylfuroxan, a classical NO donor, has been shown to significantly elevate NO levels, thereby inducing apoptosis and inhibiting proliferation and metastasis in tumor cells. It enhances the efficacy of chemotherapy, radiotherapy, and immunotherapy, reverses multidrug resistance (MDR), and impedes tumor progression. Notably, phenylsulfonylfuroxan have the ability to trigger ferroptosis in cancer cells by binding covalently to inhibit glutathione peroxidase 4 (GPX4). Recent developments in phenylsulfonylfuroxan-based therapies have positioned them as crucial in the advancement of cancer treatment modalities. This review elucidates the mechanism by which phenylsulfonylfuroxan releases NO and summarizes the significant advancements over the past 16 years in the research and development of phenylsulfonylfuroxan conjugates with various anticancer agents for targeted cancer therapy.

Coumarin as an Elite Scaffold in Anti-Breast Cancer Drug Development: Design Strategies, Mechanistic Insights, and Structure-Activity Relationships

Breast cancer is the most common cancer among women. Currently, it poses a significant threat to the healthcare system due to the emerging resistance and toxicity of available drug candidates in clinical practice, thus generating an urgent need for the development of new potent and safer anti-breast cancer drug candidates. Coumarin (chromone-2-one) is an elite ring system widely distributed among natural products and possesses a broad range of pharmacological properties. The unique distribution and pharmacological efficacy of coumarins attract natural product hunters, resulting in the identification of numerous natural coumarins from different natural sources in the last three decades, especially those with anti-breast cancer properties. Inspired by this, numerous synthetic derivatives based on coumarins have been developed by medicinal chemists all around the globe, showing promising anti-breast cancer efficacy. This review is primarily focused on the development of coumarin-inspired anti-breast cancer agents in the last three decades, especially highlighting design strategies, mechanistic insights, and their structure-activity relationship. Natural coumarins having anti-breast cancer efficacy are also briefly highlighted. This review will act as a guideline for researchers and medicinal chemists in designing optimum coumarin-based potent and safer anti-breast cancer agents.

Natural STAT3 Inhibitors for Cancer Treatment: A Comprehensive Literature Review

Cancer is one of the leading causes of mortality and morbidity worldwide, affecting millions of people physically and financially every year. Over time, many anticancer treatments have been proposed and studied, including synthetic compound consumption, surgical procedures, or grueling chemotherapy. Although these treatments have improved the daily life quality of patients and increased their survival rate and life expectancy, they have also shown significant drawbacks, including staggering costs, multiple side effects, and difficulty in compliance and adherence to treatment. Therefore, natural compounds have been considered a possible key to overcoming these problems in recent years, and thorough research has been done to assess their effectiveness. In these studies, scientists have discovered a meaningful interaction between several natural materials and signal transducer and activator of transcription 3 molecules. STAT3 is a transcriptional protein that is vital for cell growth and survival. Mechanistic studies have established that activated STAT3 can increase cancer cell proliferation and invasion while reducing anticancer immunity. Thus, inhibiting STAT3 signaling by natural compounds has become one of the favorite research topics and an attractive target for developing novel cancer treatments. In the present article, we intend to comprehensively review the latest knowledge about the effects of various organic compounds on inhibiting the STAT3 signaling pathway to cure different cancer diseases.

Application of cinnamic acid in the structural modification of natural products: A review

Natural products can generally exhibit a variety of biological activities, but most show mediocre performance in preliminary activity evaluation. Natural products often require structural modification to obtain promising lead compounds. Cinnamic acid (CA) is readily available and has diverse biological activities and low cytotoxicity. Introducing CA into natural products may improve their performance, enhance biological activity, and reduce toxic side effect. Herein, we aimed to discuss related applications of CA in the structural modification of natural products and provide a theoretical basis for future derivatization and drug development of natural products. Published articles, web databases (PubMed, Science Direct, SCI Finder, and CNKI), and clinical trial websites (https://clinicaltrials.gov/) related to natural products and CA derivatives were included in the discussion. Based on the inclusion criteria, 128 studies were selected and discussed herein. Screening natural products of CA derivatives allowed for classification by their biological activities. The full text is organized according to the biological activities of the derivatives, with the following categories: anti-tumor, neuroprotective, anti-diabetic, anti-microbial, anti-parasitic, anti-oxidative, anti-inflammatory, and other activities. The biological activity of each CA derivative is discussed in detail. Notably, most derivatives exhibited enhanced biological activity and reduced cytotoxicity compared with the lead compound. CA has various advantages and can be widely used in the synthesis of natural product derivatives to enhance the properties of drug candidates or lead compounds.

Design and Synthesis of Scopoletin Sulfonate Derivatives as Potential Insecticidal Agents

(1) Background: Scopoletin and scoparone, two naturally occurring coumarins, have garnered considerable attention and have been introduced to the market in China due to their high insecticidal efficacy and low toxicity. To investigate the structure-activity relationship of these coumarins, a series of scopoletin derivatives with aryl sulfate at C7 and different substitutes at C3 were designed and synthesized, and their insecticidal activity was studied. (2) Methods: A total of 28 new scopoletin derivatives were designed and synthesized. Most target compounds exhibited moderate insecticidal activity against the phytophagous mite Tetranychus cinnabarinus and the brine shrimp Artemia salina. (3) Results: Among these compounds, compounds 5a and 5j possessed the best insecticidal activities against T. cinnabarinus, with LC₅₀ values of 57.0 and 20.0 μg/mL, respectively, whereas that of the control drug was 15.0 μg/mL. Compound 4j exhibited selective insecticidal activities against A. salina, with an LC₅₀ value of 9.36 μg/mL, whereas its LC₅₀ value against T. cinnabarinus was 93.0 μg/mL. The enzymatic inhibitory activity on acetylcholinesterase (AChE) showed a consistent tendency with the insecticidal activity. Further molecular docking analyses predicted the binding conformations of these compounds, which showed a good correlation between the insecticidal activity and the binding scores. (4) Conclusions: In general, a decreased electron cloud density of the Δ^3,4 olefinic bond is beneficial for improving the insecticidal activity against both T. cinnabarinus and A. salina. In addition, naphthyl or benzene groups with a sulfate ester at the C7 position could further improve the insecticidal activity against A. salina. AChE was implied to be a site of action for potential insecticidal activity. The results provide insight into the rational design of a new generation of effective coumarin insecticides.

Design and synthesis of cinnamic acid triptolide ester derivatives as potent antitumor agents and their biological evaluation

A series of novel cinnamic acid triptolide ester derivatives were synthesized, and their growth inhibitory properties against human hepatoma HepG2 cells were assessed as the measure of cytotoxicity with triptolide as the positive control. One of the phenolic hydroxyl phosphorylated products, CL20 was found to possess the best cytotoxicity and surpassed the parent natural triptolide, suggesting that compound CL20 is a promising antitumor lead compound and deserves further research of pharmacological activity. In addition, the structure-activity relationship for these compounds was also investigated.

Cinnamic acid hybrids as anticancer agents: A mini-review

Cancer, as a long-lasting and dramatic disease, affects almost one-third of human beings globally. Chemotherapeutics play an important role in cancer treatment, but multidrug resistance and severe adverse effects have already become the main causes of failure in tumor chemotherapy. Therefore, it is an urgent need to develop novel chemotherapeutics. Cinnamic acid contains a ubiquitous α,β-unsaturated acid moiety presenting potential therapeutic effects in the treatment of cancer as these derivatives could act on cancer cells by diverse mechanisms of action. Accordingly, cinnamic acid derivatives are critical scaffolds in discovering novel anticancer agents. This review provides a comprehensive overview of cinnamic acid hybrids as anticancer agents. The structure-activity relationship, as well as the mechanisms of action, are also discussed, covering articles published from 2012 to 2021.

Design, synthesis and biological activity evaluation of novel scopoletin-NO donor derivatives against MCF-7 human breast cancer in vitro and in vivo

In this study, eleven new 3- and 7-positions modified scopoletin derivatives (18a-k) were designed, synthesized, and biologically evaluated against human breast cancer cell lines. Most compounds showed improved antiproliferative activity against MCF-7 and MDA-MB-231 cells and weaker cytotoxicity on human breast epithelial cell line MCF-10A than lead compound 5. Among them, compound 18e exhibited the most potent antiproliferative activity against MCF-7 cells (IC₅₀ = 0.37 ± 0.05 μM). Particularly, 18e produced the highest levels of nitric oxide (NO) intracellularly, and its antiproliferation effect was attenuated by hemoglobin (an NO scavenger). Further pharmacological research showed that 18e blocked the cell cycle at the G₂/M phase, downregulated the phosphorylation of PI3K and Akt in MCF-7 cells and regulated the expressions of the apoptosis proteins to induce apoptosis. Moreover, 18e inhibited the growth of MCF-7 in vivo. Overall, 18e is a novel anticancer agent with the abilities of high concentration of NO releasing and the inhibition of PI3K/Akt signaling pathway, and may be a promising agent against MCF-7 human breast cancer.

Microwave-Assisted Synthesis, Structural Characterization and Assessment of the Antibacterial Activity of Some New Aminopyridine, Pyrrolidine, Piperidine and Morpholine Acetamides

A series of new acetamide derivatives 22–28 of primary and secondary amines and para-toluene sulphinate sodium salt have been synthesized under microwave irradiation and assessed in vitro for their antibacterial activity against one Gram-positive and two Gram-negative bacterial species such as S. pyogenes, E. coli, and P. mirabilis using the Mueller-Hinton Agar diffusion (well diffusion) method. The synthesized compounds with significant differences in inhibition diameters and MICs were compared with those of amoxicillin, ampicillin, cephalothin, azithromycin and doxycycline. All of the evaluated acetamide derivatives were used with varying inhibition concentrations of 6.25, 12.5, 37.5, 62.5, 87.5, 112.5 and 125 µg/mL. The results show that the most important antibacterial properties were displayed by the synthetic compounds 22 and 24, both of bear a para-chlorophenyl moiety incorporated into the 2-position moiety of acetamide 1. The molecular structures of the new compounds were determined using the FT-IR and ¹H-NMR techniques.

Design and Synthesis of Molecular Hybrids of Sophora Alkaloids and Cinnamic Acids as Potential Antitumor Agents

Twenty-five sophora alkaloids-cinnamic acid hybrids (including matrine-cinnamic acid hybrids, sophoridine-cinnamic acid hybrids, and sophocarpine-cinnamic acid hybrids) were designed, synthesized, and evaluated in vitro against three human tumor cell lines (HeLa, HepG2 and A549) with cisplatin as a positive control. Some matrine-cinnamic acid and sophoridine-cinnamic acid compounds exhibited potent effect against all three cancer cell lines, such as compounds 5b, 5e, 5g, and 6d. The structure-activity relationship study of the synthesized compounds was also performed. Preliminary mechanistic studies indicated that compounds 5e and 6d could induce apoptosis in HepG2 cell line. Further, compounds 5e and 6d altered mitochondrial membrane potential and produced ROS leading to cell apoptosis of HepG2 cells. Overall, our findings suggested that these compounds may provide promising lead compounds for further development as antitumor agents by structural modification.

Synthesis and characterization of novel porphyrin-cinnamic acid conjugates

A series of novel porphyrin-cinnamic acid (porphyrin/CA) conjugates (4a-4c) have been synthesized by condensation of 5-(4-Hydroxyphenyl)-10,15,20-triphenyl- porphyrin (1) with different substituted cinnamic acids (CAs) through an alkyl linker due to the biological activities of CAs and the application of porphyrins in photodynamic therapy (PDT) of cancer. Their related zinc (II) complexes (5a-5c) were also prepared. These novel compounds have been fully characterized by ¹H NMR, Infrared (IR), Mass spectra (Ms) and Elemental analysis. The photophysical properties of these target molecules were studied by absorption and Fluorescence spectroscopy. In solution, the effect of pH, ionic strength in acid media and concentration on the aggregation behaviors of 4a has also been investigated by UV-Vis spectra. The broadened and red shifted Soret band indicated the formation of J-aggregates when the pH value was up to 2.0 in THF-aqueous solution. Furthermore, the higher ionic strength of 0.3 M NaCl in acid media resulted in the generation of J-aggregates in THF-aqueous solution. And the significant blue shift of Soret band also demonstrated the formation of H-aggregates of 4a at 1.1 × 10^-4 M in THF.

Synthesis of pyrazole acrylic acid based oxadiazole and amide derivatives as antimalarial and anticancer agents

Depravity of malaria in terms of morbidity and mortality in human beings makes it a major health issue in tropical and subtropical areas of the globe. Drug counterfeiting and non-adherence to the treatment regimen have significantly contributed to development and spread of multidrug resistance that has highlighted the need for development of novel and more efficient antimalarial drugs. Complexity associated with cancer disease and prevalence of diversified cell populations vindicates highly specific treatment options for treatment of cancer. Resistance to these anticancer agents has posed a great hindrance in successful treatment of cancer. Pondering this ongoing situation, it was speculated to develop novel compounds targeting malaria and cancer. Moving on the same aisle, we synthesized pyrazole acrylic acid based oxadiazole and amide derivatives using multi-step reaction pathways (6a-x; 6a'-h'). Schizont maturation inhibition assay was employed to determine antimalarial potential. Compound 6v emerged as the most potent antimalarial agent targeting falcipain-2 enzyme. Anticancer activity was done using sulforhodamine B assay. Compounds 6b' and 6g' demonstrated promising results against all the tested cell lines. Further, Microscopic view clearly indicated formation of apoptotic bodies, chromatin condensation, shrinkage of cells and bleb formation. Validation of the results was achieved using molecular docking studies. From the obtained results, it was observed that cyclization (oxadiazole) favored antimalarial activity while non-cyclized compounds (amides) emerged as better anticancer agents.

Synthesis and Antiradical Activity of Isoquercitrin Esters with Aromatic Acids and Their Homologues

Isoquercitrin, (IQ, quercetin-3-O-β-d-glucopyranoside) is known for strong chemoprotectant activities. Acylation of flavonoid glucosides with carboxylic acids containing an aromatic ring brings entirely new properties to these compounds. Here, we describe the chemical and enzymatic synthesis of a series of IQ derivatives at the C-6″. IQ benzoate, phenylacetate, phenylpropanoate and cinnamate were prepared from respective vinyl esters using Novozym 435 (Lipase B from Candida antarctica immobilized on acrylic resin). The enzymatic procedure gave no products with “hydroxyaromatic” acids, their vinyl esters nor with their benzyl-protected forms. A chemical protection/deprotection method using Steglich reaction yielded IQ 4-hydroxybenzoate, vanillate and gallate. In case of p-coumaric, caffeic, and ferulic acid, the deprotection lead to the saturation of the double bonds at the phenylpropanoic moiety and yielded 4-hydroxy-, 3,4-dihydroxy- and 3-methoxy-4-hydroxy-phenylpropanoates. Reducing capacity of the cinnamate, gallate and 4-hydroxyphenylpropanoate towards Folin-Ciocalteau reagent was significantly lower than that of IQ, while other derivatives displayed slightly better or comparable capacity. Compared to isoquercitrin, most derivatives were less active in 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, but they showed significantly better 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid, ABTS) scavenging activity and were substantially more active in the inhibition of tert-butylhydroperoxide induced lipid peroxidation of rat liver microsomes. The most active compounds were the hydroxyphenylpropanoates.

Discovery of oral-available resveratrol-caffeic acid based hybrids inhibiting acetylated and phosphorylated STAT3 protein

Constitutive activation of STAT3 has been found in a wide variety of cancers and demonstrated as a very attractive therapeutic target. Disrupting both acetylation and phosphorylation of STAT3 protein was hypothesized to greatly deactivate STAT3, therefore, treating cancers. To demonstrate the hypothesis, two series of novel resveratrol-caffeic acid hybrids were designed aiming to regulate both acetylation and phosphorylation of STAT3 protein, which is also the first report of the synthetic inhibitors simultaneously regulating two biological reactions of STAT3 to our knowledge. Most of these compounds were demonstrated with preferential antitumor activity with low IC₅₀ values against two cancer cell lines. Particularly, compound 7d was found as an excellent STAT3 inhibitor with over 50-fold better potency than resveratrol and caffeic acid. Meanwhile, the novel derivatives significantly inhibited the proliferation and induced the apoptosis of tumor cells. Molecular docking further disclosed the binding modes of STAT3 with the inhibitors. In addition, compound 7d orally and significantly suppressed breast cancer 4T1 xenograft tumor growth in vivo, indicating its great potential as an efficacious drug candidate for human cancer therapy.

Synthesis and antitumor activity of novel N-substituted carbazole imidazolium salt derivatives

A series of novel N-substituted carbazole imidazolium salt derivatives has been prepared and investigated for their cytotoxic activity against five human tumor cell lines by MTS assay. The results indicated that the existence of 5,6-dimethyl-benzimidazole ring, substitution of the imidazolyl-3-position with a 2-bromobenzyl or naphthylacyl group, as well as alkyl chain length between carbazole and imidazole ring were important for the antitumor activity. Compound 61, bearing a 2-bromobenzyl substituent at position-3 of the 5,6-dimethyl-benzimidazole, showed powerful inhibitory activities and was more selective to HL-60, SMMC-7721, MCF-7 and SW480 cell lines with IC50 values 0.51-2.48 μM. Mechanism of action studies revealed that this new compound could remarkably induce cell cycle arrest and apoptosis in SMMC-7721 cells. This work provides alternative novel way for future drug development based on carbazole and imidazolium salt scaffolds.

SC-III3, a novel scopoletin derivative, induces autophagy of human hepatoma HepG2 cells through AMPK/mTOR signaling pathway by acting on mitochondria

(E)-3-(4-chlorophenyl)-N-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yl) acrylamide (SC-III3), a newly synthesized derivative of scopoletin, was previously shown to reduce the viability of HepG2 cells and tumor growth of HepG2 xenograft mouse model. It induces the death of HepG2 cells by a way irrelevant to apoptosis and necrosis. To shed light on the cytotoxic mechanisms of SC-III3, the present study addresses whether and how it can induce autophagic cell death. When HepG2 cells were incubated with various concentrations of SC-III3, autophagic vacuoles could be observed by transmission electron microscopy and monodansylcadaverine staining. Increased expressions of LC3-II to LC3-I and Beclin-1, required for autophagosome formation, were accompanied. These characteristics integrally indicated that SC-III3 could initiate autophagy in HepG2 cells. N-acetyl-l-cysteine (NAC), a ROS scavenger, could reverse SC-III3-caused ROS accumulation, but it did not affect SC-III3-induced autophagy, suggesting that ROS was not involved in SC-III3-mediated autophagy in HepG2 cells. SC-III3 significantly depressed mitochondrial function, as evidenced by disruption of mitochondrial transmembrane potential and loss of the mitochondrial cristae structure, as well as decrease of Cox-I, Cox-III, Cox-IV, and ATP levels. The autophagy and activation of AMPK-TSC2-mTOR-p70s6k pathways induced by SC-III3 in HepG2 cells could be efficiently blocked by pre-treatments of compound C (an inhibitor of AMPK). Moreover, addition of extracellular ATP to the cell culture media could reverse SC-III3-caused activation of AMPK-TSC2-mTOR-p70s6k pathway, autophagy and cell viability decrease in HepG2 cells. Collectively, SC-III3 leads to autophagy through inducing mitochondrial dysfunction, depleting ATP, and activating AMPK-mTOR pathway, which thus reflects the cytotoxic effect of SC-III3 in HepG2 cells.