Synthesis and antiproliferative activity of 3- and 7-styrylcoumarins

3-styrylcoumarin scaffold-based derivatives as a new approach for leishmaniasis intervention: biological and molecular modeling studies

Seven 3-styrylcoumarins were tested for antileishmanial activity against Leishmania (Viannia) panamensis amastigotes. Cytotoxic activity was also evaluated against mammalian U-937 cells. The 3-methoxy-4-hydroxy coumarin derivative 6 was the most active with an IC50 of 40.5 µM, and did not reveal any conspicuous toxicity toward mammalian U-937 cells. Therefore, it may have potential to be considered as candidate for antileishmanial drug development. Further, among several druggable Leishmania targets, molecular docking studies revealed that compound 6 had docking preference by the N-myristoyltransferase (Lp-NMT) of Leishmania panamensis, showing a higher docking score of - 10.1 kcal mol-1 than positive controls and making this protein as a presumably druggable target for this compound. On the other hand, molecular dynamics simulations affirm the docking hypothesis, showing a conformational stability of the 6/Lp-NMT complex throughout 100 ns simulation. Moreover, the molecular mechanics/Poisson-Boltzmann surface area method also support the docking findings, revealing a total free energy of binding of - 47.26 ± 0.08 kcal mol-1, and identifying through energy decomposition analysis that those key aminoacids are contributing strongly to ligand binding. Finally, an optimal pharmacokinetic profile was also estimated for 6. Altogether, coumarin 6 could be addressed as starting point for further pharmacological studies concerning the therapeutic leishmaniasis intervention.

Graphical abstract

Comparative study of experimental and DFT calculations for 3-cinnamoyl 4-hydroxycoumarin derivatives

BACKGROUND

Computational research plays an important role in predicting the chemical and physical properties of biologically active compounds important in future structural modifications to improve or modify biological activity.

OBJECTIVE

This research focuses on quantum chemical and spectroscopic investigations properties of synthesized 4-hydroxycoumarin derivatives.

METHODS

Quantum chemical calculations were obtained using B3LYP, HF, and M06-2x level methods with the 6-31++G (d,p) basis set. Afterward, IR, 1H, 13C, UV-Visible experimentally parameters were compared with the results obtained using the B3LYP/6-31+G*(d) basis set of the molecules to be able to characterize the structures.

RESULTS

Based on the quantum chemical calculations compound with acetamido group on the phenyl ring is the most reactive, and compound with nitro substituent is the least reactive and the the strongest electrophile among tested compounds. With the exception of compounds with dimethylamino group, all other compounds have a pronounced tautomer between OH and C = O group. The calculated and experimental values are in agreement with each other.

CONCLUSION

The molecular structure in the ground state of six 3-cinnamoyl 4-hydroxycoumarin derivatives was optimized using density functional theory. The observed and computed values were compared and it can be concluded that the theoretical results were in good linear agreement with the experimental data.

Synthesis of novel coumarin-hydrazone hybrids as α-glucosidase inhibitors and their molecular docking studies

Diabetes mellitus is a metabolic disorder and more than 90% of diabetic patients suffer from type-2 diabetes, which is characterized by hyperglycemia. α-Glucosidase inhibition has become an appropriate approach to tackle high blood glucose levels. The current study was focused on synthesizing coumarin-hydrazone hybrids (7a-i) by using facile chemical reactions. The synthesized compounds were characterized by using 1H-NMR, 13C-NMR, and IR. To evaluate their anti-diabetic capability, all of the conjugates were screened for in vitro α-glucosidase inhibitory activity to reveal their therapeutic importance. All of the compounds (except 7b) demonstrated significant enzyme inhibitory potential with IC50 values ranging between 2.39-57.52 μM, as compared to the standard inhibitor, acarbose (IC50 = 873.34 ± 1.67 μM). Among them, compound 7c is the most potent α-glucosidase inhibitor (IC50 = 2.39 ± 0.05 μM). Additionally, molecular docking was employed to scrutinize the binding pattern of active compounds within the α-glucosidase binding site. The in silico analysis reflects that hydrazone moiety is an essential pharmacophore for the binding of compounds with the active site residues of the enzyme. This study demonstrates that compounds 7c and 7f deserve further molecular optimization for potential application in diabetic management.

Dodonaea viscosa Jacq. induces cytotoxicity, antiproliferative activity, and cell death in colorectal cancer cells via regulation of caspase 3 and p53

Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide and is the second leading cause of cancer-related death due to an insufficiency prognosis and is generally diagnosed in the last step of development. The Peruvian flora has a wide variety of medicinal plants with therapeutic potential in several diseases. Dodonaea viscosa Jacq. is a plant used to treat inflammatory process as well as gastrointestinal diseases. The aim of this study was to examine the cytotoxic, antiproliferative, and cell death-inducing effects of D. viscosa on colorectal cancer cells (SW480 and SW620). The hydroethanolic extract was obtained by maceration at 70% ethanol, the phytochemical constituents were identified by LC-ESI-MS. D. viscosa revealed 57 compounds some of them are: isorhamnetin, kaempferol, quercetin, methyl dodovisate B, hardwickiic acid, viscosol, and dodonic acid. Regarding the antitumoral activity, D. viscosa induced cytotoxic and antiproliferative activity in both SW480 and SW620 cancer cells, accompanied with, important changes in mitochondrial membrane potential, formation of the Sub G0/G1 population and increasing levels of apoptotic biomarkers (caspase 3 and the tumor suppressor protein p53) in the metastatic derivative cell line (SW620), suggesting an intrinsic apoptotic process after the treatment with the hydroethanolic extract of D. viscosa.

Chemopreventive Effect on Human Colon Adenocarcinoma Cells of Styrylquinolines: Synthesis, Cytotoxicity, Proapoptotic Effect and Molecular Docking Analysis

Seven styrylquinolines were synthesized in this study. Two of these styrylquinolines are new and were elucidated by spectroscopic analysis. The chemopreventive potential of these compounds was evaluated against SW480 human colon adenocarcinoma cells, its metastatic derivative SW620, and normal cells (HaCaT). According to the results, compounds 3a and 3d showed antiproliferative activity in SW480 and SW620 cells, but their effect seemed to be caused by different mechanisms of action. Compound 3a induced apoptosis independent of ROS production, as evidenced by increased levels of caspase 3, and had an immunomodulatory effect, positively regulating the production of different immunological markers in malignant cell lines. In contrast, compound 3d generated a pro-oxidant response and inhibited the growth of cancer cells, probably by another type of cell death other than apoptosis. Molecular docking studies indicated that the most active compound, 3a, could efficiently bind to the proapoptotic human caspases-3 protein, a result that could provide valuable information on the biochemical mechanism for the in vitro cytotoxic response of this compound in SW620 colon carcinoma cell lines. The obtained results suggest that these compounds have chemopreventive potential against CRC, but more studies should be carried out to elucidate the molecular mechanisms of action of each of them in depth.

Evaluation of the Effects of Genistein In Vitro as a Chemopreventive Agent for Colorectal Cancer—Strategy to Improve Its Efficiency When Administered Orally

Colorectal Cancer (CRC) ranks third in terms of incidence and second in terms of mortality and prevalence worldwide. In relation to chemotherapy treatment, the most used drug is 5-fluorouracil (5-FU); however, the use of this drug generates various toxic effects at the systemic level. For this reason, new therapeutic strategies are currently being sought that can be used as neoadjuvant or adjuvant treatments. Recent research has shown that natural compounds, such as genistein, have chemotherapeutic and anticancer effects, but the mechanisms of action of genistein and its molecular targets in human colon cells have not been fully elucidated. The results reported in relation to non-malignant cell lines are also unclear, which does not allow evidence of the selectivity that this compound may have. Therefore, in this work, genistein was evaluated in vitro in both cancer cell lines SW480 and SW620 and in the non-malignant cell line HaCaT. The results obtained show that genistein has selectivity for the SW480 and SW620 cell lines. In addition, it inhibits cell viability and has an antiproliferative effect in a dose-dependent manner. Increased production of reactive oxygen species (ROS) was also found, suggesting an association with the cell death process through various mechanisms. Finally, the encapsulation strategy that was proposed made it possible to demonstrate that bacterial nanocellulose (BNC) is capable of protecting genistein from the acidic conditions of gastric fluid and also allows the release of the compound in the colonic fluid. This would allow genistein to act locally in the mucosa of the colon where the first stages of CRC occur.

Colorectal Cancer Chemoprevention by S-Allyl Cysteine–Caffeic Acid Hybrids: In Vitro Biological Activity and In Silico Studies

Conventional chemotherapy for colorectal cancer (CRC) gives only a small increase in patient survival, since it is often diagnosed at late stages, when the tumor has disseminated to other organs. Moreover, it is common to observe that malignant cells may acquire resistance to conventional chemotherapies through different mechanisms, including reducing drug activation or accumulation (by enhancing efflux), inducing alterations in molecular targets, and inhibiting the DNA damage response, among other strategies. Considering these facts, the discovery of new molecules with therapeutic potential has become an invaluable tool in chemoprevention. In this context, we previously evaluated two hybrids (SAC-CAFA-MET and SAC-CAFA-PENT) that exhibited selective cytotoxicity against SW480 cells, with better results than the conventional chemotherapeutic agent (5-fluorouracil; 5-FU). Here, we investigated the possible mechanisms of these molecules in greater depth, to identify whether they could be valuable therapeutic scaffolds in the search for new molecules with chemopreventive potential for the treatment of CRC. Both compounds reduced ROS formation, which could be related to antioxidant effects. Further evaluations showed that SAC-CAFA-MET induces cell death independent of caspases and the tumor-suppressor protein p53, but probably mediated by the negative regulation of the pro-apoptotic Bcl-2. In addition, the lack of activation of caspase-8 and the positive regulation of caspase-3 induced by SAC-CAFA-PENT suggest that this compound acts through an apoptotic mechanism, probably initiated by intrinsic pathways. Furthermore, the downregulation of IL-6 by SAC-CAFA-PENT suggests that it also induces a significant anti-inflammatory process. In addition, docking studies would suggest caspase-3 modulation as the primary mechanism by which SAC-CAFA-PENT elicits apoptosis in SW480human colorectal adenocarcinoma cells. Meanwhile, density functional theory (DFT) calculations suggest that both hybrids would produce effects in the modulation of ROS in SW480 cells via the hydrogen atom transfer (HAT) pathway. The present work notes that SAC-CAFA-MET and SAC-CAFA-PENT could be potential candidates for further investigations in the search for potential chemopreventive agents.

Proapoptotic Effect and Molecular Docking Analysis of Curcumin–Resveratrol Hybrids in Colorectal Cancer Chemoprevention

Different hybrids based on curcumin and resveratrol were previously synthesized and characterized by spectroscopic techniques. The most active molecules (3a, 3e, 3i, and 3k) were evaluated in vitro as an approach to determine the possible mechanism of action of the hybrids. The results indicated that the evaluated curcumin/resveratrol hybrids induce mitochondrial instability in SW620 and SW480 cells. Moreover, these molecules caused a loss in membrane integrity, suggesting an apoptotic process mediated by caspases after the treatment with compounds 3i (SW480) and 3k (SW620). In addition, the results suggest that the mechanism of action of the hybrids could be independent of the p53 status. Furthermore, hybrids 3e and 3i caused G0/G1 phase arrest, which highlights the potential of these molecules not only as cytotoxic but also as cytostatic compounds. Hybrids 3e and 3i caused a negative modulation of the matrix metalloproteinase 7 (MMP7) on SW480 cells. These curcumin resveratrol hybrids could be potential candidates for further investigations in the search for potential chemopreventive agents, even in those cases with resistance to conventional chemotherapy because of the lack of p53 expression or function. Molecular docking simulations showed that compounds 3e, 3i, and 3k bind efficiently to proapoptotic human caspases 3/7 proteins, as well as human MMP-7 and p53, which, in turn, could explain at the molecular level the in vitro cytotoxic effect of these compounds in SW480 and SW620 colon cancer cell lines.

Styryl Group, a Friend or Foe in Medicinal Chemistry

The styryl (Ph-CH=CH-R) group is widely represented in medicinally important compounds, including drugs, clinical candidates, and molecular probes as it positively impacts the lipophilicity, oral absorption, and biological activity. The analysis of matched molecular pairs (styryl vs. phenethyl, phenyl, methyl, H) for the biological activity indicates the superiority aspect of styryl compounds. However, the Michael acceptor site in the styryl group makes it amenable to the nucleophilic attack by biological nucleophiles and transformation to the toxic metabolites. One of the downsides of styryl compounds is isomerization that impacts the molecular conformation and directly affects biological activity. The impact of cis-trans isomerism and isosteric replacements on biological activity is exemplified. We also discuss the styryl group-bearing drugs, clinical candidates, and fluorescent probes. Overall, the present review reveals the utility of the styryl group in medicinal chemistry and drug discovery.

Theoretical study on the radical scavenging activity and mechanism of four kinds of Gnetin molecule

As an important subgroup of resveratrol oligomers, Gnetins received much attention due to their antioxidants. The four Gnetin molecules are divided into two major categories according to different structures, type-A (Gnetin-C, Gnetin-D) and type-B (Gnetin-L, Gnetin-F). Density functional theory (DFT) has been performed thermodynamically and kinetically in detail to analyze the structure and antioxidant activity of four Gnetins toward OH/OOH radical in the gas and solvents phase with four possible antioxidant mechanisms, namely, Hydrogen-atom transfer (HAT), Single electron transfer followed by proton transfer (SET-PT), Sequential proton-loss electron transfer (SPLET), and Radical adduct formation (RAF). From these calculations; Gnetins' order of antioxidant activity was estimated as: Gnetin-C ≈ Gnetin-L > Resveratrol > Gnetin-D > Gnetin-F. All investigations suggested that type A has a higher radical scavenging activity compared to type B. On the basis of the structure-activity relationship, type A structure may have more vital antioxidant potential in the future.

Phytochemical Screening of Himatanthus sucuuba (Spruce) Woodson (Apocynaceae) Latex, In Vitro Cytotoxicity and Incision Wound Repair in Mice

Himatanthus sucuuba, also known as "Bellaco caspi", is a medicinal plant whose latex, stem bark, and leaves possess phenolic acids, lupeol, β-dihydro-plumbericinic acid, plumericin, and plumeride, among other components. Some of these have been linked to such biological activities as antiulcer, anti-inflammatory, and wound healing. The aim of this study was to determine the phytochemical compounds of H. sucuuba latex, as well as its in vitro cytotoxicity and wound healing effect in mice. Latex was collected in the province of Iquitos, Peru. Phytochemical analysis was carried out with UPLC-ESI-MS/MS. The cytotoxicity was evaluated on two colon tumor cell lines (SW480 and SW620) and non-malignant cells (human keratinocytes, HaCaT, and Chinese hamster ovary, CHO-K1). The mice were distributed into two groups, as follows: Group I-control (n = 10; without treatment); II-(n = 10) H. sucuuba latex; wounds were induced with a scalpel in the dorsal-cervical area and treatments were applied topically twice a day on the incision for 10 days. Molecular docking was carried out on the glycogen synthase kinase 3β protein. Twenty-four chemical compounds were determined, mainly flavonoid-type compounds. Latex did not have a cytotoxic effect on tumor cells with IC₅₀ values of more than 500 µg/mL. The latex had a regenerative effect on wounds in mice. Acacetin-7-O-neohesperidoside had the best docking score of -9.9 kcal/mol. In conclusion, H. sucuuba latex had a wound healing effect in mice, as confirmed by histological study. However, a non-cytotoxic effect was observed on colon tumor cells SW480 and SW620.

New Hybrids Based on Curcumin and Resveratrol: Synthesis, Cytotoxicity and Antiproliferative Activity against Colorectal Cancer Cells

We synthesized twelve hybrids based on curcumin and resveratrol, and their structures were elucidated by spectroscopic analysis. The chemopreventive potential of these compounds was evaluated against SW480 human colon adenocarcinoma cells, its metastatic derivative SW620, along with the non-malignant CHO-K1 cell line. Among the tested compounds, hybrids 3e and 3i (for SW480) and 3a, 3e and 3k (for SW620) displayed the best cytotoxic activity with IC₅₀ values ranging from 11.52 ± 2.78 to 29.33 ± 4.73 µM for both cell lines, with selectivity indices (SI) higher than 1, after 48 h of treatment. Selectivity indices were even higher than those reported for the reference drug, 5-fluorouracil (SI = 0.96), the starting compound resveratrol (SI = 0.45) and the equimolar mixture of curcumin plus resveratrol (SI = 0.77). The previous hybrids showed good antiproliferative activity.

An Overview of Coumarin as a Versatile and Readily Accessible Scaffold with Broad-Ranging Biological Activities

Privileged structures have been widely used as an effective template for the research and discovery of high value chemicals. Coumarin is a simple scaffold widespread in Nature and it can be found in a considerable number of plants as well as in some fungi and bacteria. In the last years, these natural compounds have been gaining an increasing attention from the scientific community for their wide range of biological activities, mainly due to their ability to interact with diverse enzymes and receptors in living organisms. In addition, coumarin nucleus has proved to be easily synthetized and decorated, giving the possibility of designing new coumarin-based compounds and investigating their potential in the treatment of various diseases. The versatility of coumarin scaffold finds applications not only in medicinal chemistry but also in the agrochemical field as well as in the cosmetic and fragrances industry. This review is intended to be a critical overview on coumarins, comprehensive of natural sources, metabolites, biological evaluations and synthetic approaches.

Synthesis of furocoumarin-stilbene hybrids as potential multifunctional drugs against multiple biochemical targets associated with Alzheimer's disease

A series of furocoumarin-stilbene hybrids has been synthesized and evaluated in vitro for inhibitory effect against acetylcholinesterase (AChE), butyrylcholinestarase (BChE), β-secretase, cyclooxygenase-2 (COX-2), and lipoxygenase-5 (LOX-5) activities including free radical-scavenging properties. Among these hybrids, 8-(3,5-dimethoxyphenyl)-4-(3,5-dimethoxystyryl)furochromen-2-one 4h exhibited significant anticholinesterase activity and inhibitory effect against β-secretase, COX-2 and LOX-5 activities. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and an in vitro cell-based antioxidant activity assay involving lipopolysaccharide induced reactive oxygen species production revealed that 4h has capability of scavenging free radicals. Molecular docking into AChE, BChE, β-secretase, COX-2 and LOX-5 active sites has also been performed.

Investigation of the cytotoxicity of bioinspired coumarin analogues towards human breast cancer cells

Abstract

Coumarins possess a wide array of therapeutic capabilities, but often with unclear mechanism of action. We tested a small library of 18 coumarin derivatives against human invasive breast ductal carcinoma cells with the capacity of each compound to inhibit cell proliferation scored, and the most potent coumarin analogues selected for further studies. Interestingly, the presence of two prenyloxy groups (5,7-diprenyloxy-4-methyl-coumarin, 4g) or the presence of octyloxy substituent (coumarin 4d) was found to increase the potency of compounds in breast cancer cells, but not against healthy human fibroblasts. The activity of potent compounds on breast cancer cells cultured more similarly to the conditions of the tumour microenvironment was also investigated, and increased toxicity was observed. Results suggest that tested coumarin derivatives could potentially reduce the growth of tumour mass. Moreover, their use as (combination) therapy in cancer treatment might have the potential of causing limited side effects.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s11030-020-10082-6) contains supplementary material, which is available to authorized users.