f.)

In the first phytochemical investigation of specialized metabolites from the stem bark of Alyxia fascicularis, which is used in different traditional medicines, including those of Myanmar and China, five lignans (1-5) and three coumarins (6-8) were isolated by semipreparative HPLC separations and identified mainly by 1D and 2D NMR spectral analysis. The radical scavenging activity of isolated compounds was tested using the DPPH method. Noteworthy, most lignans exhibited antiradical effects comparable to vitamin C and gallic acid. Instead, compounds 1-8 showed no cytotoxic effect on Hela cell line. A possible biosynthetic pathway to enantiomeric 3 and 4 is suggested.

A new 3,4-dihydroisocoumarin and an antiinflammatory coumarin from the roots of Saposhnikovia divaricata (Turcz.) Schischk

Phytochemical investigation of the roots of Saposhnikovia divaricata (Turcz.) Schischk resulted in the isolation of twelve coumarin derivatives including one new 3,4-dihydroisocoumarin (1) and eleven known 3,4-unsubstituted coumarins (2-12). Structural elucidation of compounds 1-12 was established by 1D and 2D NMR spectra referring to the literature, together with high-resolution mass spectrometric analysis. LPS-induced RAW264.7 inflammatory cell model was used to determine the potential antiinflammation activity of all the isolated compounds in vitro. The results showed that compound 3 significantly inhibited the production of lipopolysaccharide (LPS)-induced NO in macrophages (IC50 = 4.54 ± 1.71 μM), more active than the positive control (L-NMMA).

Isolating Antipathogenic Fungal Coumarins from Coriaria nepalensis and Determining Their Primary Mechanism In Vitro

Through bioassay-guided isolation, eight undescribed coumarins (1-8), along with six reported coumarins (9-14), were obtained from Coriaria nepalensis. The new structures were determined by using IR, UV, NMR, HRESIMS, and ECD calculations. The results of the biological activity assays showed that compound 9 exhibited broad spectrum antifungal activities against all tested fungi in vitro and a significant inhibitory effect on Phytophthora nicotianae with an EC50 value of 3.00 μg/mL. Notably, compound 9 demonstrated greater curative and protective effects against tobacco balack shank than those of osthol in vivo. Thus, 9 was structurally modified to obtain new promising antifungal agents, and the novel derivatives (17b, 17j, and 17k) exhibited better effects on Sclerotinia sclerotiorum than did lead compound 9. Preliminary mechanistic exploration illustrated that 9 could enhance cell membrane permeability, destroy the morphology and ultrastructure of cells, and reduce the exopolysaccharide content of P. nicotianae mycelia. Furthermore, the cytotoxicity results revealed that compound 9 exhibited relatively low cytotoxicity against HEK293 cell lines with an inhibition rate of 33.54% at 30 μg/mL. This research is promising for the discovery of new fungicides from natural coumarins with satisfactory ecological compatibility.

Benzopyrone, a privileged scaffold in drug discovery: An overview of FDA-approved drugs and clinical candidates

Natural products have always served as an important source of drugs for treating various diseases. Among various privileged natural product scaffolds, the benzopyrone class of compounds has a substantial presence among biologically active compounds. One of the pioneering anticoagulant drugs, warfarin approved in 1954 bears a benzo-α-pyrone (coumarin) nucleus. The widely investigated psoriasis drugs, methoxsalen, and trioxsalen, also contain a benzo-α-pyrone nucleus. Benzo-γ-pyrone (chromone) containing drugs, cromoglic acid, and pranlukast were approved as treatments for asthma in 1982 and 2007, respectively. Numerous other small molecules with a benzopyrone core are under clinical investigation. The present review discusses the discovery, absorption, distribution, metabolism, excretion properties, and synthetic approaches for the Food and Drug Administration-approved and clinical-stage benzopyrone class of compounds. The role of the pyrone core in biological activity has also been discussed. The present review unravels the potential of benzopyrone core in medicinal chemistry and drug development.

roots

Ferulago nodosa (L.) Boiss. (Apiaceae) is a species occurring in the Balkan-Tyrrhenian area being present in Crete, Greece, Albania, and probably in Macedonia. From the roots of this accession of species, not previously investigated, four coumarins, grandivittin, aegelinol benzoate, felamidin and aegelinol, and two terpenoids, (2E)-3-methyl-4-[(3-methyl-1-oxo-2-buten-1yl)oxy]-2-butenoic acid and pressafonin-A, were isolated and spectroscopically characterized. The last one was never detected in Ferulago species. The evaluation of the anti-tumor effects of F. nodosa coumarins on colon cancer HCT116 cells showed only a modest effect on reduction of tumor cell viability. For aegelinol, the reduction of colon cancer cell viability already appears with 25 µΜ, while using 50 e 100 µM doses of marmesin the residual viability amounted to 70% and 54%, respectively. This effect resulted more evident at higher doses of compounds (at 200 µM from 80% to 0%). The most effective compounds resulted coumarins lacking ester group.

Structurally Diverse Coumarins from Peucedanum praeruptorum and their Anti-Inflammatory Activities via NF-κB Signaling Pathway

The phytochemical study of Peucedanum praeruptorum led to the isolation of twenty-five coumarins (1-25). Of which, (±) praeruptol A (±1), one pair of previous undescribed seco-coumarin enantiomers were obtained. Their structures were established according to HR-ESI-MS, NMR, X-ray single crystal diffraction analysis, as well as ECD calculation. All compounds were tested for anti-inflammatory activity in the RAW264.7 macrophage model, and eight compounds (7-10, and 13-16) exhibited significant inhibitory effects with IC50 values ranging from 9.48 to 34.66 μM. Among them, compound 7 showed the strongest inhibitory effect, which significantly suppressed the production of IL-6, IL-1β, and TNF-α, as well as iNOS and COX-2 in a concentration-dependent manner. Further investigated results showed that compound 7 exerted an anti-inflammatory effect via the NF-κB signaling pathway.

PDR9 allelic variation and MYB63 modulate nutrient-dependent coumarin homeostasis in Arabidopsis

Plant roots release phytochemicals into the soil environment to influence nutrient availability and uptake. Arabidopsis thaliana roots release phenylpropanoid coumarins in response to iron (Fe) deficiency, likely to enhance Fe uptake and improve plant health. This response requires sufficient phosphorus (P) in the root environment. Nonetheless, the regulatory interplay influencing coumarin production under varying availabilities of Fe and P is not known. Through genome-wide association studies, we have pinpointed the influence of the ABC transporter G family member, PDR9, on coumarin accumulation and trafficking (homeostasis) under combined Fe and P deficiency. We show that genetic variation in the promoter of PDR9 regulates its expression in a manner associated with coumarin production. Furthermore, we find that MYB63 transcription factor controls dedicated coumarin production by regulating both COUMARIN SYNTHASE (COSY) and FERULOYL-CoA 6'-HYDROXYLASE 1 (F6'H1) expression while orchestrating secretion through PDR9 genes under Fe and P combined deficiency. This integrated approach illuminates the intricate connections between nutrient signaling pathways in coumarin response mechanisms.

The Different Composition of Coumarins and Antibacterial Activity of Phlojodicarpus sibiricus and Phlojodicarpus villosus Root Extracts

Phlojodicarpus sibiricus, a valuable endangered medicinal plant, is a source of angular pyranocoumarins used in pharmacology. Due to limited resource availability, other pyranocoumarin sources are needed. In the present research, the chemical composition of a closely related species, Phlojodicarpus villosus, was studied, along with P. sibiricus. High-performance liquid chromatography and mass-spectrometric analyses, followed by antibacterial activity studies of root extracts from both species, were performed. P. sibiricus and P. villosus differed significantly in coumarin composition. Pyranocoumarins predominated in P. sibiricus, while furanocoumarins predominated in P. villosus. Osthenol, the precursor of angular pyrano- and furanocoumarins, was detected in both P. sibiricus and P. villosus. Angular forms of coumarins were detected in both species according to the mass-spectrometric behavior of the reference. Thus, P. villosus cannot be an additional source of pyranocoumarins because their content in the plant is critically low. At the same time, the plant contained large amounts of hydroxycoumarins and furanocoumarins. The extracts exhibited moderate antibacterial activity against five standard strains. The P. villosus extract additionally suppressed the growth of the Gram-negative bacterium E. coli. Thus, both Phlojodicarpus species are promising for further investigation in the field of pharmaceuticals as producers of different coumarins.

Coumarins and flavones with anti-inflammatory activity isolated from the branches and leaves of Daphne retusa

In this study, two new (1, 13) and fourteen known (2-12, 14-16) compounds were isolated from the branches and leaves of Daphne retusa. On the basis of chemical evidence and spectral data analysis (UV, ECD NMR, and HR-ESI-MS), the structures of new compounds were elucidated. Furthermore, all compounds have been tested for their inhibitory effects on NO production in LPS-induced RAW 264.7 cells, and compound 3 showed obvious inhibitory effect. Through target screening and molecular docking technology, potential binding targets for compound 3 to exert anti-inflammatory effects have been predicted.

Syntheses, reactivity, and biological applications of coumarins

This comprehensive review, covering 2021-2023, explores the multifaceted chemical and pharmacological potential of coumarins, emphasizing their significance as versatile natural derivatives in medicinal chemistry. The synthesis and functionalization of coumarins have advanced with innovative strategies. This enabled the incorporation of diverse functional fragments or the construction of supplementary cyclic architectures, thereby the biological and physico-chemical properties of the compounds obtained were enhanced. The unique chemical structure of coumarine facilitates binding to various targets through hydrophobic interactions pi-stacking, hydrogen bonding, and dipole-dipole interactions. Therefore, this important scaffold exhibits promising applications in uncountable fields of medicinal chemistry (e.g., neurodegenerative diseases, cancer, inflammation).

Efficient and Stable Multicolor Emissions of the Coumarin-Modified Cs3 LnCl6 Lead-Free Perovskite Nanocrystals and LED Application

Lanthanide-based lead-free perovskite materials hold great promise for the development of high-resolution full-color displays in the future. Here, various Cs3 LnCl6 perovskite nanocrystals (NCs) emitting light across the visible to near-infrared spectrum with remarkably high photoluminescence quantum yield (PLQY) are systemically prepared. Especially, by introducing multifunctional coumarin small molecules into Cs3 EuCl6 NCs as an intermediate state, Cs3 EuCl6 NCs can achieve an impressive PLQY of 92.4% with pure red emission and an exceptional energy transfer efficiency of nearly 93.2%. Furthermore, the lanthanide-based electroluminescent devices in red, green, and blue are successfully fabricated. Among them, the Cs3 EuCl6 -NC-based red light-emitting diode (LED) demonstrates a FWHM of 18 nm at 617 nm, an external quantum efficiency up to 5.17%, and a maximum brightness of 2373 cd m-2 , which is the most excellent reported for lead-free narrowband (within 20 nm) emission devices. Notably, these devices exhibit an operating half-life of 440 h at a brightness level of 100 cd m-2 , surpassing the performance of most reported lead-free perovskite LEDs (PLEDs). This work opens up exciting possibilities for the future commercialization of lanthanide-based PLEDs in the display industry, paving the way for more vibrant, energy-efficient, and long-lasting display technologies.

Chemical constituents from the stem barks of Calophyllum recurvatum P.F. Stevens and Calophyllum andersonii P.F. Stevens, and their in-vitro hepatotoxic activity

Bioactive phenolics can be found in abundance in Calophyllum species. Phytochemical studies are carried out on the stem bark of Calophyllum recurvatum and Calophyllum andersonii, which has led to the isolation and elucidation of phytochemicals, thwaitesixanthone (1), teysmanone A (2), soulattrolide (3), calanone (4), isocalanone (5) and friedelin (6), respectively. The cytotoxic activities of compounds (2), (3), (4) and (5) as well as plant extracts were tested against HeLa Chang liver, HepG2 and HL-7702 cell lines. Phenylpyranocoumarins, teysmanone A (2) and soulattrolide (3) portrayed appreciable cytotoxicity activities at 42.57 ± 1.20 and 34.53 ± 3.41 µg/mL, respectively against HepG2 cell line comparable to the positive control, curcumin. Meanwhile, n-hexane extract from C. recurvatum exhibited cytotoxicity with the IC50 value of 36.43 ± 0.64 and 26.25 ± 4.83 µg/mL against HeLa Chang liver and HepG2 cell lines. All the tested compounds and plant extracts displayed non-cytotoxic properties on HL-7702 cell line.

Natural and Synthetic Coumarins as Potential Drug Candidates Against SARS-CoV-2/CoViD-19

COVID-19, an airborne disease caused by a betacoronavirus named SARS-- CoV-2, was officially declared a pandemic in early 2020, resulting in more than 770 million confirmed cases and over 6.9 million deaths by September 2023. Although the introduction of vaccines in late 2020 helped reduce the number of deaths, the global effort to fight COVID-19 is far from over. While significant progress has been made in a short period, the fight against SARS-CoV-2/COVID-19 and other potential pandemic threats continues. Like AIDS and hepatitis C epidemics, controlling the spread of COVID-19 will require the development of multiple drugs to weaken the virus's resistance to different drug treatments. Therefore, it is essential to continue developing new drug candidates derived from natural or synthetic small molecules. Coumarins are a promising drug design and development scaffold due to their synthetic versatility and unique physicochemical properties. Numerous examples reported in scientific literature, mainly by in silico prospection, demonstrate their potential contribution to the rapid development of drugs against SARS-CoV-2/COVID-19 and other emergent and reemergent viruses.

Bioactivity and toxicity of coumarins from African medicinal plants

Introduction: Coumarins are naturally occuring metabolites from plants and a few micro-organisms. They have been widely used in the food and drug industry in their natural or synthetic forms. Numerous coumarins possess several biological activities such as anti-inflammatory, anti-ulcers, anti-tumour, anti-microbial, anti-coagulant. The aim of this study was to assess the bioactivity, and toxicity of coumarins from African medicinal plants. Methods: We searched online databases and search engines such as PubMed, Google Scholar and Web of Science for key terms such as coumarins, toxicity, bioavailability, bioactivity with appropriate Boolean operators. Only full-length research articles published in English between 1956 to 2023 were reviewed. Results: We recorded 22 coumarins from 15 plant species from Africa. Most of the plant species (33%) were from North Africa. These were followed by East Africa at 21%, then West, and Central Africa at 18.2% each. Most of the coumarins (21.3%) were isolated from the entire plant and the leaves (19.1%) and most of them (46.7%) had some antimicrobial activity. Five coumarins viz osthole, pseudocordatolide C & calanolide, chartreusin and esculetin had either antitumor or anticancer activity. Six coumarins had varying levels and types of toxicity ranging from inhibiting blood clotting as anticoagulants, to cytotoxic effects, causing hyperventilation, tremor, & photophobia, pulmonary haemorrhage, carcinogenic activity, severe neurotoxicity, hepato- and phototoxicity. Conclusion: Several African medicinal plants are sources of various coumarins that possess several biological activities as well as toxicities. This calls for more research into their safety and efficacy because of their wide spread applications as therapeutic agents.

Chemical Analysis and Investigation of Antimicrobial and Antibiofilm Activities of Prangos trifida (Apiaceae)

Plants of the genus Prangos are intensively investigated as potential new sources of bioactive isolated products. In this work, the chemical composition of volatile constituents (essential oils and headspace volatiles) and dichloromethane extracts, as well as antimicrobial and antibiofilm activities of essential oils and MFDEs (methanol fractions of dichloromethane extracts) of Prangos trifida from Serbia, were investigated. Volatiles of roots, leaves, stems and fruits, and fatty acids and phytosterols in dichloromethane extracts of roots and fruits were analyzed by GC-FID-MS, whereas coumarins in MFDEs by LC-MS and some isolated coumarins by 1H-NMR. Minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations/minimum fungicidal concentrations (MBCs/MFCs) of essential oils and MFDEs were determined against 13 microorganisms. Antibiofilm activity was assessed against four microorganisms. Additionally, congo red and ergosterol binding assays were conducted to elucidate selected mechanisms of antibiofilm action in the case of Candida albicans. Total of 52 volatile constituents, 16 fatty acids, eight phytosterols and 10 coumarins were identified. Essential oils demonstrated significant activity, surpassing that of commercial food preservatives, against six tested molds from the Aspergillus, Penicillium and Trichoderma genera, as well as against bacteria Staphylococcus aureus and Bacillus cereus. Most of the oils strongly inhibited the formation of biofilms by S. aureus, Listeria monocytogenes and Escherichia coli. MFDEs exhibited noteworthy effects against B. cereus and the tested Aspergillus species, particularly A. niger, and significantly inhibited C. albicans biofilm formation. This inhibition was linked to a marked reduction in exopolysaccharide production, while antifungal mechanisms associated with ergosterol remained unaffected.

New coumarin from the roots of Prangos pabularia growing wild in Tajikistan

Dichloromethane and butanol extracts of the roots of Prangos pabularia were analyzed to determine chemical constituents and biological activity. The new coumarin 1, yuganin B ((5-(((2S,3R,4S,5S,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-((2-oxo-2H-chromen-7-yl)oxy)tetrahydro-2H-pyran-3-yl)oxy)-3,4-dihydroxytetrahydrofuran-3-yl)methyl 4-hydroxy-3-methoxybenzoate) along with three phenolic and twenty-four known coumarins were isolated from the roots of Prangos pabularia, and the structures of these isolated compounds were elucidated by UV, HR-ESIMS, and 1 D and 2 D NMR spectroscopy. In addition, the anti-melanogenic effect of several of the isolated individual compounds and their inhibitory effect on B16 cells were evaluated. Isolating and testing compounds may proof to be useful in the treatment of hyperpigmentation and as a skin-whitening agent in the cosmetics industry.

Rapid solid-liquid dynamic extraction of Cachrys pungens Jan ex Guss. aerial parts: influence on the photobiological and antioxidant properties

Cachrys pungens Jan ex Guss. (Apiaceae) is a perennial plant native to Italy and Northwestern Africa. This species is known for its content in furanocoumarins, and the methanolic extract obtained with maceration previously demonstrated significant phototoxicity on 375 melanoma cells. Here, in order to better explain the biological effects, the apoptotic responses on melanoma cancer cell line were verified. The aerial parts were extracted with methanol through an innovative solid-liquid extraction technology, the Naviglio extractor®, and the raw extract was tested for its photobiological properties on human melanoma C32 cells irradiated with UVA light. The in vitro antioxidant potential was assessed as well. The sample exerted a concentration-dependent photocytotoxic activity (IC50 value = 3.00 ± 0.16 µg/mL). In line with these evidences, in C32-treated cells subjected to UV irradiation, further data have reported an up-regulation of p53 and PARP, both proteins involved in apoptotic response and DNA repair.

An Effective, Green Synthesis Procedure for Obtaining Coumarin-Hydroxybenzohydrazide Derivatives and Assessment of Their Antioxidant Activity and Redox Status

In this study, green synthesis of two derivatives of coumarin-hydroxybenzohydrazide, (E)-2,4-dioxo-3-(1-(2-(2,3,4-trihydroxybenzoyl)hydrazyl)ethylidene)-chroman-7-yl acetate (C-HB1), and (E)-2,4-dioxo-3-(1-(2-(3,4,5-trihydroxybenzoyl)hydrazyl)ethylidene)chroman-7-yl acetate (C-HB2) is reported. Using vinegar and ethanol as a catalyst and solvent, the reactions were carried out between 3-acetyl-4-hydroxy-coumarin acetate and corresponding trihydroxybenzoyl hydrazide. The antioxidant potential of these compounds was investigated using the DPPH and ABTS assays, as well as the FRAP test. The obtained results reveal that even at very low concentrations, these compounds show excellent radical scavenging potential. The IC50 values for C-HB1 and C-HB2 in relation to the DPPH radical are 6.4 and 2.5 μM, respectively, while they are 4.5 and 2.0 μM in relation to the ABTS radical. These compounds have antioxidant activity that is comparable to well-known antioxidants such as gallic acid, NDGA, and trolox. These results are in good correlation with theoretical parameters describing these reactions. Moreover, it was found that inhibition of DPPH● follows HAT, while inactivation of ABTS+● follows SET-PT and HAT mechanisms. Additionally, coumarin-hydroxybenzohydrazide derivatives induced moderate cytotoxic activity and show significant potential to modulate redox status in HCT-116 colorectal cancer cells. The cytotoxicity was achieved via their prooxidative activity and ability to induce oxidative stress in cancer cells by increasing O2˙- concentrations, indicated by increased MDA and GSH levels. Thus, ROS manipulation can be a potential target for cancer therapies by coumarins, as cancer cells possess an altered redox balance in comparison to normal cells. According to the ADMET analysis, the compounds investigated show good pharmacokinetic and toxicological profiles similar to vitamin C and gallic acid, which makes them good candidates for application in various fields of industry and medicine.

Isolation and structure elucidation of antioxidant compounds from stem and root barks of Daphne giraldii

Two new compounds, aphegiractin A1/A2 (1a/1b), and seven known compounds were isolated by phytochemical work on EtOAc-soluble ingredients extracted from stem and root barks of Daphne giraldii. Their structures were established based on extensive spectroscopic methods, including HRESIMS, CD experiments, 1D and 2D NMR. All compounds were evaluated for their antioxidant activity to DPPH, ABTS radical scavenging activity and inhibitory activity on tyrosinase. Of these compounds, compound 3 exhibited significant antioxidant activities.

Targeting carbonic anhydrases for the management of hypoxic metastatic tumors

INTRODUCTION

Several isoforms of the metalloenzyme carbonic anhydrase (CA, EC 4.2.1.1) are connected with tumorigenesis. Hypoxic tumors overexpress CA IX and XII as a consequence of HIF activation cascade, being involved in pH regulation, metabolism, and metastases formation. Other isoforms (CA I, II, III, IV) were also reported to be present in some tumors.

AREAS COVERED

Some CA isoforms are biomarkers for disease progression or response to therapy. Inhibitors, antibodies, and other procedures for targeting these enzymes for the treatment of tumors/metastases are discussed. Sulfonamides and coumarins represent the most investigated classes of inhibitors, but carboxylates, selenium, and tellurium-containing inhibitors were also investigated. Hybrid drugs of CA inhibitors with other antitumor agents for multitargeted therapy were reported.

EXPERT OPINION

Targeting CAs present in solid or hematological tumors with selective, targeted inhibitors is a validated approach, which has been consolidated in the last years. A host of new preclinical data and several clinical trials of antibodies and small-molecule inhibitors are ongoing, which connected with the large number of new chemotypes/procedures discovered to be effective, may lead to a breakthrough in this therapeutic area. The scientific/patent literature has been searched for on PubMed, ScienceDirect, Espacenet, and PatentGuru, from 2018 to 2023.

Evaluation of Antibacterial Activity against Nosocomial Pathogens of an Enzymatically Derived α-Aminophosphonates Possessing Coumarin Scaffold

The purpose of the present study was to evaluate the synergistic effect of two important pharmacophores, coumarin and α-amino dimethyl phosphonate moieties, on antimicrobial activity against selected strains of multidrug-resistant nosocomial pathogenic bacteria. The previously developed enzyme-catalysed Kabachnik-Fields protocol allowed us to obtain the studied compounds with high yields which were free from metal impurities. The structure-activity relationship revealed that inhibitory activity is strongly related to the presence of the trifluoromethyl group (CF3-) in the coumarin scaffold. MIC and MBC studies carried out on six selected pathogenic bacterial strains (Gram-positive pathogenic Staphylococcus aureus (ATCC 23235) strain, as well as on Gram-negative Acinetobacter baumannii (ATCC 17978), Pseudomonas aeruginosa (ATCC 15442), Enterobacter cloacae (ATCC 49141), Porphyromonas gingivalis (ATCC 33277), and Treponema denticola (ATCC 35405)) have shown that tested compounds show a strong bactericidal effect at low concentrations. Among all agents investigated, five exhibit higher antimicrobial activity than those observed for commonly used antibiotics. It should be noted that all the compounds tested showed very high activity against S. aureus, which is the main source of nosocomial infections that cause numerous fatalities. Furthermore, we have shown that the studied coumarin-based α-aminophosphonates, depending on their structural characteristics, are non-selective and act efficiently against various Gram-positive and Gram-negative pathogens, which is of great importance for hospitalised patients.

Coumarins from Jinhua Finger Citron: Separation by Liquid-Liquid Chromatography and Potential Antitumor Activity

In this paper, liquid-liquid chromatography was introduced for the first time for the separation of fingered citron (Citrus medica L. var. sarcodactylis Swingle). The fingered citron cultivated in Jinhua is of significant industrial and medicinal value, with several major coumarin compounds detected in its extract. Therefore, further separation for higher purity was of necessity. A preparative liquid-liquid chromatographic method was developed by combining two elution modes (isocratic and step-gradient) with selection according to different polarities of the target sample. Five coumarin derivatives-5,7-dimethoxycoumarin (52.6 mg, 99.6%), phellopterin (4.9 mg, 97.1%), 5-prenyloxy-7-methoxycoumarin (6.7 mg, 98.7%), 6-hydroxy-7-methoxycoumarin (7.1 mg, 82.2%), and byakangelicol (10.5 mg, 90.1%)-with similar structures and properties were isolated on a large scale from 100 mg of petroleum ether (PE) extract and 100 mg of ethyl acetate (EA) extract in Jinhua fingered citron. The productivity was much improved. The anti-growth activity of the isolated coumarins was evaluated against three cancer cell lines (HeLa, A549, and MCF7) with an MTT assay. The coumarins demonstrated potential anti-tumor activity on the HeLa cell line, with 5,7-dimethoxycoumarin in particular exhibiting the best anti-growth activity (IC50 = 10.57 ± 0.24 μM) by inhibiting proliferation. It inhibited colony formation and reduced the size of the tumor sphere in a concentration-dependent manner. The main mechanism was confirmed as inducing apoptosis. This work was informative for further studies aimed at exploring new natural-product-based antitumor agents.

Comparative Contents of Polyphenolic Compounds in Aerial Parts of Cirsium esculentum, C. serratuloides, and Ancathia igniaria (Asteraceae)

Because Ancathia igniaria (Spreng.) DC. (Cirsium igniarium Spreng.) has been segregated as a monotypic genus from the genus Cirsium on the basis of phylogenetic data, chemotaxonomic differences are of interest to detect in the composition of polyphenolic components of aerial plant parts. Phenolic compounds are of chemotaxonomic significance in a number of genera and families. The polyphenolic profile of aerial parts was therefore compared for Cirsium esculentum (Siev.) C.A. Mey., Cirsium serratuloides (L.) Hill, and A. igniaria. The last two species were for the first time examined in this context. The compounds were identified against known standard via high-performance liquid chromatography (HPLC). The species of the genus Cirsium were found to have similar compositions of simple phenols, but differ in the set of flavonoids. Six to eight phenolic compounds were detected in the species, and three simple polyphenols (syringin, chlorogenic acid, and ethyl gallate) proved to be common. The flavonoid profiles of aerial parts included rutin in both Cirsium species. Cymaroside and quercetin-3-O-β-D-diglucoside-O-α-L-rhamnoside were species specific for C. serratuloides; salipurposide and hyperoside, for C. esculentum. An extract of A. igniaria aerial parts contained cinaroside (like in C. serratuloides), chrysin 7-O-glucoside, and eriodictyol. A greater difference in flavonoid composition was observed between the genera Cirsium and Ancathia. Data on phenolic compound composition are of importance for chemosystematics and use of plants as medicinal raw materials. The total content of coumarins, aglycones, and flavonoid glycosides in the species was determined by a spectrophotometric method. The contents of flavonoids and coumarins in C. esculentum and C. serratuloides were comparable and exceeded their contents in A. igniaria. Thus, A. igniaria proved to differ from the genus Cirsium in the quantitative and qualitative composition of phenolic compounds.

Evaluation of Anti-Inflammatory and Anti-Tubercular Activity of 4-Methyl-7-Substituted Coumarin Hybrids and Their Structure Activity Relationships

Four sets of previously synthesized 4-methyl-7-substituted coumarin derivatives were screened for their in vitro anti-inflammatory and anti-tubercular activities. The anti-inflammatory potential of 3a-t, 5a-o, 6a-n, and 7a-f synthesized compounds was evaluated by an anti-denaturation assay using diclofenac sodium as the reference standard. Evaluation of the anti-tuberculous activity of the mentioned compounds was performed by the Resazurin test method against four different TB strains using rifampicin and isoniazid as reference drugs. Based on the anti-inflammatory results, compounds 3o, 5f, 6c, and 7d proved to be the most active compounds in their respective series. Additionally, compounds 3k-n, 5b-d, 6d-f, 6k, 7a, and 7f were found to be the most potent anti-tuberculous agents. In fact, most of the screened compounds exhibited promising activity profiles compared to the respective standard drugs. The structure-activity connections revealed a few intriguing aspects, indicating that the presence of electron-donating and nitrogen-rich fragments boost the anti-inflammatory effects of the examined compounds. However, the presence of electron-withdrawing substituents was required to boost the anti-tubercular activity of the evaluated compounds.

Natural product-inspired synthesis of coumarin-chalcone hybrids as potential anti-breast cancer agents

Twelve novel neo-tanshinlactone-chalcone hybrid molecules were constructed through a versatile methodology involving the Horner-Wadsworth-Emmons (HWE) olefination of 4-formyl-2H-benzo [h]chromen-2-ones and phosphonic acid diethyl esters, as the key step, and evaluated for anticancer activity against a series of four breast cancers and their related cell lines, viz. MCF-7 (ER + ve), MDA-MB-231 (ER-ve), HeLa (cervical cancer), and Ishikawa (endometrial cancer). The title compounds showed excellent to moderate in vitro anti-cancer activity in a range of 6.8-19.2 µM (IC50). Compounds 30 (IC50 = 6.8 µM and MCF-7; IC50 = 8.5 µM and MDA-MB-231) and 31 (IC50 = 14.4 µM and MCF-7; IC50 = 15.7 µM and MDA-MB-231) exhibited the best activity with compound 30 showing more potent activity than the standard drug tamoxifen. Compound 30 demonstrated a strong binding affinity with tumor necrosis factor α (TNF-α) in molecular docking studies. This is significant because TNFα is linked to MCF-7 cancer cell lines, and it enhances luminal breast cancer cell proliferation by upregulating aromatase. Additionally, virtual ADMET studies confirmed that hybrid compounds 30 and 31 met Lipinski's rule; displayed high bioavailability, excellent oral absorption, favorable albumin interactions, and strong penetration capabilities; and improved blood-brain barrier crossing. Based on the aforementioned results, compound 30 has been identified as a potential anti-breast cancer lead molecule.

Chemical Constituents from Ficus sagittifolia Stem Bark and Their Antimicrobial Activities

The phytochemical investigation of the ethylacetate fraction of an ethanolic extract obtained from the stem bark of Ficus sagittifolia (Moraceae) led to the isolation of four flavonoids: (2R)-eriodictyol (1), 2'- hydroxygenistein (2), erycibenin A (3), and genistein (4); a dihydrobenzofuran: moracin P (5); a coumarin: peucedanol (6); and an apocarotenoid terpenoid: dihydrophaseic acid (7). These were identified via 1D and 2D nuclear magnetic resonance spectroscopy (NMR) and ultra-high-resolution liquid chromatography-quadrupole time-of-flight mass spectroscopy (UHPLC-QTOF MS). Moracin P (5) is being reported for the first time in the genus Ficus, while the others are known compounds (1-4 and 6-7) isolated previously from the genus but being reported for the first time from the species F. sagittifolia. Their antimicrobial activity against various pathogens (five bacteria: Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella typhi; two fungi: Aspergillus niger and Candida albicans) was tested. The mixture of genistein and moracin P (4+5) exhibited strong activity against K. pneumoniae (MIC < 0.0039 mg/mL), whereas dihydrophaseic acid (7) was the most active against P. aeruginosa and A. niger (MIC = 0.0078 and <0.0039 mg/mL, respectively). These compounds might be considered potential antimicrobial agents with the potential to be starting points for the development of antimicrobial drugs.

Conformation of the Ester Group Governs the Photophysics of Highly Polarized Benzo[g]coumarins

Photosensitizers that display "unusual" emission from upper electronically excited states offer possibilities for initiating higher-energy processes than what the governing Kasha's rule postulates. Achieving conditions for dual fluorescence from multiple states of the same species requires molecular design and conditions that favorably tune the excited-state dynamics. Herein, we switch the position of the electron-donating NMe₂ group around the core of benzo[g]coumarins (BgCoum) and tune the electronic coupling and the charge-transfer character of the fluorescent excited states. For solvents with intermediate polarity, three of the four regioisomers exhibit fluorescence from two different excited states with bands that are well separated in the visible and the near-infrared spectral regions. Computational analysis, employing ab initio methods, reveals that the orientation of an ester on the pyrone ring produces two conformers responsible for the observed dual fluorescence. Studies with solid solvating media, which restricts the conformational degrees of freedom, concur with the computational findings. These results demonstrate how "seemingly inconsequential" auxiliary substituents, such as the esters on the pyrone coumarin rings, can have profound effects leading to "anti-Kasha" photophysical behavior important for molecular photonics, materials engineering, and solar-energy science.

Synthesis of Altissimacoumarin D and Other Prenylated Coumarins and Their Ability to Reverse the Multidrug Resistance Phenotype in Candida albicans

Azoles are the main antifungal agents employed in clinical practice to treat invasive candidiasis. Nonetheless, their efficacy is limited by fungal resistance mechanisms, mainly the overexpression of efflux pumps. Consequently, candidiasis has a worrisome death rate of 75%. One potential strategy to overcome efflux-mediated resistance is to inhibit this process. Ailanthus altissima is a Chinese tree that produces several active substances, including altissimacoumarin D. Due to the low yield of its extraction and the need to search for new drugs to treat candidiasis, this study aimed to synthesize altissimacoumarin D and its analogues, as well as evaluating their ability to reverse the resistance phenotype of Candida albicans. Coumarin isofraxidin was prepared via total synthesis through a solvent-free Knoevenagel condensation as the key step. Isofraxidin and other commercially available coumarins were alkylated with prenyl or geranyl groups to yield the natural product altissimacoumarin D and seven analogues. The antifungal activity of the coumarins and their ability to reverse the fungal resistance phenotype were assessed using microbroth methodologies. Toxicity was evaluated using erythrocytes and an in silico prediction. All compounds improved the antifungal activity of fluconazole by inhibiting efflux pumps, and ACS47 and ACS50 were the most active. None of the coumarins were toxic to erythrocytes. In silico predictions indicate that ACS47 and ACS50 may be safe for human use. ACS47 and ACS50 are promising candidates when used as adjuvants in the antifungal therapy against C. albicans-resistant strains.

Recent Developments in Coumarin Derivatives as Neuroprotective Agents

BACKGROUND

Neurodegenerative diseases are among the diseases that cause the foremost burden on the health system of the world. The diseases are multifaceted and difficult to treat because of their complex pathophysiology, which includes protein aggregation, neurotransmitter breakdown, metal dysregulation, oxidative stress, neuroinflammation, excitotoxicity, etc. None of the currently available therapies has been found to be significant in producing desired responses without any major side effects; besides, they only give symptomatic relief otherwise indicated off-episode relief. Targeting various pathways, namely choline esterase, monoamine oxidase B, cannabinoid system, metal chelation, -secretase, oxidative stress, etc., may lead to neurodegeneration. By substituting various functional moieties over the coumarin nucleus, researchers are trying to produce safer and more effective neuroprotective agents.

OBJECTIVES

This study aimed to review the current literature to produce compounds with lower side effects using coumarin as a pharmacophore.

METHODS

In this review, we have attempted to compile various synthetic strategies that have been used to produce coumarin and various substitutional strategies used to produce neuroprotective agents from the coumarin pharmacophore. Moreover, structure-activity relationships of substituting coumarin scaffold at various positions, which could be instrumental in designing new compounds, were also discussed.

RESULTS

The literature review suggested that coumarins and their derivatives can act as neuroprotective agents following various mechanisms.

CONCLUSION

Various studies have demonstrated the neuroprotective activity of coumarin due to an oxaheterocyclic loop, which allows binding with a broad array of proteins, thus motivating researchers to explore its potential as a lead against various neurodegenerative diseases.

Structure-Based Design of Novel MAO-B Inhibitors: A Review

With the significant growth of patients suffering from neurodegenerative diseases (NDs), novel classes of compounds targeting monoamine oxidase type B (MAO-B) are promptly emerging as distinguished structures for the treatment of the latter. As a promising function of computer-aided drug design (CADD), structure-based virtual screening (SBVS) is being heavily applied in processes of drug discovery and development. The utilization of molecular docking, as a helping tool for SBVS, is providing essential data about the poses and the occurring interactions between ligands and target molecules. The current work presents a brief discussion of the role of MAOs in the treatment of NDs, insight into the advantages and drawbacks of docking simulations and docking software, and a look into the active sites of MAO-A and MAO-B and their main characteristics. Thereafter, we report new chemical classes of MAO-B inhibitors and the essential fragments required for stable interactions focusing mainly on papers published in the last five years. The reviewed cases are separated into several chemically distinct groups. Moreover, a modest table for rapid revision of the revised works including the structures of the reported inhibitors together with the utilized docking software and the PDB codes of the crystal targets applied in each study is provided. Our work could be beneficial for further investigations in the search for novel, effective, and selective MAO-B inhibitors.

Daphnetin, a Coumarin with Anticancer Potential against Human Melanoma: In Vitro Study of Its Effective Combination with Selected Cytostatic Drugs

(1) The treatment of metastatic or drug-resistant melanoma is still a significant therapeutic problem. The aim of this study was to evaluate the anticancer potential of daphnetin (7,8-dihydroxycoumarin) and its combinations with five different cytostatic drugs (mitoxantrone, docetaxel, vemurafenib, epirubicin and cisplatin). (2) The viability, proliferation and cytotoxicity of daphnetin against four human malignant melanoma cell lines were evaluated. The interactions were assessed using isobolographic analysis for the combinations of daphnetin with each of the five cytostatic drugs. (3) Daphnetin showed anticancer activity against malignant melanoma, with IC₅₀ values ranging from 40.48 ± 10.90 µM to 183.97 ± 18.82 µM, depending on the cell line. The combination of daphnetin with either vemurafenib or epirubicin showed an antagonistic interaction. Moreover, additive interactions were observed for the combinations of daphnetin with cisplatin and docetaxel. The most desirable synergistic interactions for human melanoma metastatic cell lines were observed for the combination of daphnetin with mitoxantrone. (4) The obtained results suggest that daphnetin should not be combined with vemurafenib or epirubicin in the treatment of malignant melanoma due to the abolition of their anticancer effects. The combination of daphnetin with mitoxantrone is beneficial in the treatment of metastatic melanoma due to their synergistic interaction.

Conformationally Restricted Glycoconjugates Derived from Arylsulfonamides and Coumarins: New Families of Tumour-Associated Carbonic Anhydrase Inhibitors

The involvement of carbonic anhydrases (CAs) in a myriad of biological events makes the development of new inhibitors of these metalloenzymes a hot topic in current Medicinal Chemistry. In particular, CA IX and XII are membrane-bound enzymes, responsible for tumour survival and chemoresistance. Herein, a bicyclic carbohydrate-based hydrophilic tail (imidazolidine-2-thione) has been appended to a CA-targeting pharmacophore (arylsulfonamide, coumarin) with the aim of studying the influence of the conformational restriction of the tail on the CA inhibition. For this purpose, the coupling of sulfonamido- or coumarin-based isothiocyanates with reducing 2-aminosugars, followed by the sequential acid-promoted intramolecular cyclization of the corresponding thiourea and dehydration reactions, afforded the corresponding bicyclic imidazoline-2-thiones in good overall yield. The effects of the carbohydrate configuration, the position of the sulfonamido motif on the aryl fragment, and the tether length and substitution pattern on the coumarin were analysed in the in vitro inhibition of human CAs. Regarding sulfonamido-based inhibitors, the best template turned out to be a d-galacto-configured carbohydrate residue, meta-substitution on the aryl moiety (9b), with K_i against CA XII within the low nM range (5.1 nM), and remarkable selectivity indexes (1531 for CA I and 181.9 for CA II); this provided an enhanced profile in terms of potency and selectivity compared to more flexible linear thioureas 1-4 and the drug acetazolamide (AAZ), used herein as a reference compound. For coumarins, the strongest activities were found for substituents devoid of steric hindrance (Me, Cl), and short linkages; derivatives 24h and 24a were found to be the most potent inhibitors against CA IX and XII, respectively (K_i = 6.8, 10.1 nM), and also endowed with outstanding selectivity (K_i > 100 µM against CA I, II, as off-target enzymes). Docking simulations were conducted on 9b and 24h to gain more insight into the key inhibitor-enzyme interactions.

New coumarin derivatives accessible in short and eco-friendly conditions with antifungal activity

Aim: The synthesis of a novel class of compounds bearing a coumarin entity was targeted. They are either iminocoumarins or characterized by the presence of a pyridone ring fused within the iminocoumarin scaffold. Methods & results: The targeted compounds were synthesized through a short method, thanks to microwave activation. The study evaluated the antifungal activity of 13 newly synthesized compounds against a new fungal strain of Aspergillus niger. The most active compound showed activity comparable to the widely used reference drug, amphotericin B. Conclusion: The conditions and the ease of synthesis warrant high potential of the method for diversity-oriented synthesis, very useful within the drug discovery area.

Nematicidal Coumarins from Cnidium monnieri Fruits and Angelica dahurica Roots and Their Physiological Effect on Pine Wood Nematode (Bursaphelenchus xylophilus)

Pine wood nematode (PWN), Bursaphelenchus xylophilus, is a major pathogen of pine wilt disease (PWD), which is a devastating disease affecting pine trees. Eco-friendly plant-derived nematicides against PWN have been considered as promising alternatives to control PWD. In this study, the ethyl acetate extracts of Cnidium monnieri fruits and Angelica dahurica roots were confirmed to have significant nematicidal activity against PWN. Through bioassay-guided fractionations, eight nematicidal coumarins against PWN were separately isolated from the ethyl acetate extracts of C. monnieri fruits and A. dahurica roots, and they were identified to be osthol (Compound 1), xanthotoxin (Compound 2), cindimine (Compound 3), isopimpinellin (Compound 4), marmesin (Compound 5), isoimperatorin (Compound 6), imperatorin (Compound 7), and bergapten (Compound 8) by mass and nuclear magnetic resonance (NMR) spectral data analysis. Coumarins 1-8 were all determined to have inhibitory effects on the egg hatching, feeding ability, and reproduction of PWN. Moreover, all eight nematicidal coumarins could inhibit the acetylcholinesterase (AChE) and Ca²⁺ ATPase of PWN. Cindimine 3 from C. monnieri fruits showed the strongest nematicidal activity against PWN, with an LC₅₀ value of 64 μM at 72 h, and the highest inhibitory effect on PWN vitality. In addition, bioassays on PWN pathogenicity demonstrated that the eight nematicidal coumarins could effectively relieve the wilt symptoms of black pine seedlings infected by PWN. The research identified several potent botanical nematicidal coumarins for use against PWN, which could contribute to the development of greener nematicides for PWD control.

Synthesis of Artesunic Acid-Coumarin Hybrids as Potential Antimelanoma Agents

Current therapy against melanoma relies on surgical treatment or, in alternative, on conventional drug therapy. Often these therapeutic agents are ineffective due to the development of resistance phenomena. For this purpose, chemical hybridization emerged as an effective strategy to overcome the development of drug resistance. In this study, a series of molecular hybrids were synthesized combining the sesquiterpene artesunic acid with a panel of phytochemical coumarins. Cytotoxicity, antimelanoma effect, and cancer selectivity of the novel compounds were evaluated by MTT assay on primary and metastatic cells and on healthy fibroblasts as a reference. The two most active compounds showed lower cytotoxicity and higher activity against metastatic melanoma than paclitaxel and artesunic acid. Further tests, including cellular proliferation, apoptosis, confocal microscopy, and MTT analyses in the presence of an iron chelating agent, were conducted with the aim of tentatively addressing the mode of action and the pharmacokinetic profile of selected compounds.

Hogweed Seed Oil: Physico-Chemical Characterization, LC-MS Profile, and Neuroprotective Activity of Heracleum dissectum Nanosuspension

The seeds of dissected hogweed (Heracleum dissectum Ledeb., Apiaceae) are the source of hogweed oil (HSO), which is still underexplored and requires careful chemical and biological studies. The performed physico-chemical analysis of HSO elucidated basic physical characteristics and revealed the presence of fatty acids, essential oil components, pigments, and coumarins. High-performance liquid chromatography with photodiode array detection and electrospray ionization triple quadrupole mass spectrometric detection (HPLC-PDA-ESI-tQ-MS/MS) identified 38 coumarins that were characterized and quantified. Various furanocoumarins were the major components of HSO polyphenolics, including imperatorin, phellopterin, and isoimperatorin, and the total coumarin content in HSO varied from 181.14 to 238.42 mg/mL. The analysis of storage stability of the selected compounds in HSO indicated their good preservation after 3-year storage at cold and freezing temperatures. The application of the CO₂-assisted effervescence method allowed the production of an HSO nanosuspension, which was used in a brain ischemia model of rats. The HSO nanosuspension enhanced cerebral hemodynamics and decreased the frequency of necrotic processes in the brain tissue. Thus, H. dissectum seeds are a good source of coumarins, and HSO nanosuspension promotes neuroprotection of the brain after lesions, which supports earlier ethnopharmacological data.

Antioxidant Activity of Coumarins and Their Metal Complexes

Ubiquitously present in plant life, coumarins, as a class of phenolic compounds, have multiple applications-in everyday life, in organic synthesis, in medicine and many others. Coumarins are well known for their broad spectrum of physiological effects. The specific structure of the coumarin scaffold involves a conjugated system with excellent charge and electron transport properties. The antioxidant activity of natural coumarins has been a subject of intense study for at least two decades. Significant research into the antioxidant behavior of natural/semi-synthetic coumarins and their complexes has been carried out and published in scientific literature. The authors of this review have noted that, during the past five years, research efforts seem to have been focused on the synthesis and examination of synthetic coumarin derivatives with the aim to produce potential drugs with enhanced, modified or entirely novel effects. As many pathologies are associated with oxidative stress, coumarin-based compounds could be excellent candidates for novel medicinal molecules. The present review aims to inform the reader on some prominent results from investigations into the antioxidant properties of novel coumarin compounds over the past five years.

Enzymatic Synthesis of a Novel Coumarin Aminophosphonates: Antibacterial Effects and Oxidative Stress Modulation on Selected E. coli Strains

The objective of the present study was to evaluate the synergistic effect of two important pharmacophores, coumarin and α-amino dimethyl phosphonate moieties, on antimicrobial activity toward selected LPS-varied E. coli strains. Studied antimicrobial agents were prepared via a Kabachnik-Fields reaction promoted by lipases. The products were provided with an excellent yield (up to 92%) under mild, solvent- and metal-free conditions. A preliminary exploration of coumarin α-amino dimethyl phosphonate analogs as novel antimicrobial agents was carried out to determine the basic features of the structure responsible for the observed biological activity. The structure-activity relationship revealed that an inhibitory activity of the synthesized compounds is strongly related to the type of the substituents located in the phenyl ring. The collected data demonstrated that coumarin-based α-aminophosphonates can be potential antimicrobial drug candidates, which is particularly crucial due to the constantly increasing resistance of bacteria to commonly used antibiotics.

Three undescribed coumarins from the roots of Angelica pubescens

Three undescribed coumarins, 6-(3-hydroxy-3-methyl-2-oxobutyl)-7-methoxycoumarin (1), (R)-6-(1,3-dihydroxy-3-methyl-2-oxobutyl)-7-methoxycoumarin (2), angelol N (6), together with four known coumarins were isolated from the roots of Angelica pubescens. Their structures were determined by extensive spectroscopic analyses. The absolute configurations of compounds 2 and 6 were assigned via electronic circular dichroism (ECD). Their inhibitory effects on lipopoly-saccharide (LPS)-induced nitric oxide (NO) production in RAW264.7 cells were evaluated. Compounds 1-4 exhibited moderate inhibitory activities.

Studies on the Accumulation of Secondary Metabolites and Evaluation of Biological Activity of In Vitro Cultures of Ruta montana L. in Temporary Immersion Bioreactors

The present work focuses on in vitro cultures of Ruta montana L. in temporary immersion Plantform^TM bioreactors. The main aim of the study was to evaluate the effects of cultivation time (5 and 6 weeks) and different concentrations (0.1-1.0 mg/L) of plant growth and development regulators (NAA and BAP) on the increase in biomass and the accumulation of secondary metabolites. Consequently, the antioxidant, antibacterial, and antibiofilm potentials of methanol extracts obtained from the in vitro-cultured biomass of R. montana were evaluated. High-performance liquid chromatography analysis was performed to characterize furanocoumarins, furoquinoline alkaloids, phenolic acids, and catechins. The major secondary metabolites in R. montana cultures were coumarins (maximum total content of 1824.3 mg/100 g DM), and the dominant compounds among them were xanthotoxin and bergapten. The maximum content of alkaloids was 561.7 mg/100 g DM. Concerning the antioxidant activity, the extract obtained from the biomass grown on the 0.1/0.1 LS medium variant, with an IC₅₀ 0.90 ± 0.03 mg/mL, showed the best chelating ability among the extracts, while the 0.1/0.1 and 0.5/1.0 LS media variants showed the best antibacterial (MIC range 125-500 µg/mL) and antibiofilm activity against resistant Staphylococcus aureus strains.

Photobiological effect of eugenol-derived 3-benzoylcoumarin associated with led lights against MDR microorganisms

The problem of antibiotic resistance by bacteria threatens human health. Therefore, studies in this area seek alternatives to circumvent it. The study with coumarins and eugenol has already proven that these classes of compounds act against bacteria. In this same aspect, exposure to LED also shows a bactericidal effect. Seeking a possible enhancement of this effect, the present work studied coumarins derived from eugenol in association with LED to investigate the bactericidal effect. Four compounds were tested. For this, minimum inhibitory concentrations (MICs) and modulation with three antibiotics against Escherichia coli and Staphylococcus aureus bacteria were determined. To test the behavior of the activity against exposure to LED, the plates were exposed for 20 min to blue light, 415 nm and then incubated at 37°C for 24 h. For control, duplicates were made, and one of them did not undergo this exposure. C1 exhibited better activity against S. aureus, as synergism prevailed under the conditions tested. C3 and C4 were promising against E. coli as they showed synergism in association with the three antibiotics both with and without LED exposure. Thus, the compounds showed bactericidal activity, and LED was shown to enhance synergism.

[Investigation of the chemical components of Ciwujia injection using ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry]

Ciwujia injection is commonly used to treat cerebrovascular and central nervous system diseases in clinical practice. It can significantly improve blood lipid levels and endothelial cell function in patients with acute cerebral infarction and promote the proliferation of neural stem cells in cerebral ischemic brain tissues. The injection has also been reported to have good curative effects on cerebrovascular diseases, such as hypertension and cerebral infarction. At present, the material basis of Ciwujia injection remains incompletely understood, and only two studies have reported dozens of components, which were determined using high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF MS). Unfortunately, the lack of research on this injection restricts the in-depth study of its therapeutic mechanism.In the present study, a qualitative method based on ultra-high performance liquid chromatography-quadrupole-electrostatic field orbitrap high-resolution mass spectrometry (UHPLC-Q/Orbitrap HRMS) was developed to analyze the chemical components of Ciwujia injection. Separation was performed on a BEH Shield RP18 column (100 mm×2.1 mm, 1.7 μm) using 0.1% formic acid aqueous solution (A) and acetonitrile (B) as the mobile phases, and gradient elution was performed as follows: 0-2 min, 0%B; 2-4 min, 0%B-5%B; 4-15 min, 5%B-20%B; 15-15.1 min, 20%B-90%B; 15.1-17 min, 90%B. The flow rate and column temperature were set to 0.4 mL/min and 30 ℃ respectively. MS1 and MS2 data were acquired in both positive- and negative-ion modes using a mass spectrometer equipped with an HESI source. For data post-processing, a self-built library including component names, molecular formulas, and chemical structures was established by collecting information on the isolated chemical compounds of Acanthopanax senticosus. The chemical components of the injection were identified by comparison with standard compounds or MS2 data in commercial databases or literature based on precise relative molecular mass and fragment ion information. The fragmentation patterns were also considered. For example, the MS2 data of 3-caffeoylquinic acid (chlorogenic acid), 4-caffeoylquinic acid (cryptochlorogenic acid), and 5-caffeoylquinic acid (neochlorogenic acid) were first analyzed. The results indicated that these compounds possessed similar fragmentation behaviors, yielding product ions at m/z 173 and m/z 179 simultaneously. However, the abundance of the product ion at m/z 173 was much higher in 4-caffeoylquinic acid than in 5-caffeoylquinic acid or 3-caffeoylquinic acid, and the fragment signal at m/z 179 was much stronger for 5-caffeoylquinic acid than for 3-caffeoylquinic acid. Four caffeoylquinic acids were identified using a combination of abundance information and retention times. MS2 data in commercial database and literature were also used to identify unknown constituents. For example, compound 88 was successfully identified as possessing a relative molecular mass and neutral losses similar to those of sinapaldehyde using the database, and compound 80 was identified as salvadoraside because its molecular and fragmentation behaviors were consistent with those reported in the literature. A total of 102 constituents, including 62 phenylpropanoids, 23 organic acids, 7 nucleosides, 1 iridoid, and 9 other compounds, were identified. The phenylpropanoids can be further classified as phenylpropionic acids, phenylpropanols, benzenepropanals, coumarins, and lignans. Among the detected compounds, 16 compounds were confirmed using reference compounds and 65 compounds were identified in Ciwujia injection for the first time. This study is the first to report the feasibility of using the UHPLC-Q/Orbitrap HRMS method to quickly and comprehensively analyze the chemical components of Ciwujia injection. The 27 newly discovered phenylpropanoids provide further material basis for the clinical treatment of neurological diseases and new research targets for the in-depth elucidation of the pharmacodynamic mechanism of Ciwujia injection and its related preparations.

Plant Coumarins with Anti-HIV Activity: Isolation and Mechanisms of Action

This review summarizes and systematizes the literature on the anti-HIV activity of plant coumarins with emphasis on isolation and the mechanism of their antiviral action. This review summarizes the information on the anti-HIV properties of simple coumarins as well as annulated furano- and pyranocoumarins and shows that coumarins of plant origin can act by several mechanisms: inhibition of HIV reverse transcriptase and integrase, inhibition of cellular factors that regulate HIV-1 replication, and transmission of viral particles from infected macrophages to healthy ones. It is important to note that some pyranocoumarins are able to act through several mechanisms or bind to several sites, which ensures the resistance of these compounds to HIV mutations. Here we review the last two decades of research on the anti-HIV activity of naturally occurring coumarins.

Diversity in Phytochemical Composition and Medicinal Value of Murraya paniculata

Murraya paniculata is herbal medicinal plant which is traditionally being used for management of cardiovascular, intestinal and respiratory (air way) disorders. This evergreen plant of tropical regions is a member of Rutaceace family. The goal of this review is to analyze and report the biological activities and active phytochemicals reported from Murraya paniculata (M. paniculata) extracts and essential oil. The data was searched using different search engines and using specific key words including M. paniculata, herbal medicine, phytochemicals, extract, essential oil, pharmacological activities. M. paniculata has been found to have wide range of pharmacological activities, including antinociceptive, antianxiety, antioxidant, antidepressant, antibacterial, analgesic and anti-diabetic properties. A diverse range of phytochemicals, including phenols, coumarins, terpenoids, flavonoids, and alkaloids have been isolated from various portions of the plant and tested for a variety of biological activities. This review will provide more information and stimulate additional research to develop more effective and cost-efficient alternative medicine from this plant.

Evaluation of the Antiseizure Activity of Endemic Plant Halfordia kendack Guillaumin and Its Main Constituent, Halfordin, on a Zebrafish Pentylenetetrazole (PTZ)-Induced Seizure Model

Epilepsy is a neurological disease that burdens over 50 million people worldwide. Despite the considerable number of available antiseizure medications, it is estimated that around 30% of patients still do not respond to available treatment. Herbal medicines represent a promising source of new antiseizure drugs. This study aimed to identify new drug lead candidates with antiseizure activity from endemic plants of New Caledonia. The crude methanolic leaf extract of Halfordia kendack Guillaumin (Rutaceae) significantly decreased (75 μg/mL and 100 μg/mL) seizure-like behaviour compared to sodium valproate in a zebrafish pentylenetetrazole (PTZ)-induced acute seizure model. The main coumarin compound, halfordin, was subsequently isolated by liquid-liquid chromatography and subjected to locomotor, local field potential (LFP), and gene expression assays. Halfordin (20 μM) significantly decreased convulsive-like behaviour in the locomotor and LFP analysis (by 41.4% and 60%, respectively) and significantly modulated galn, and penka gene expression.

Comparative Untargeted Metabolic Profiling of Different Parts of Citrus sinensis Fruits via Liquid Chromatography-Mass Spectrometry Coupled with Multivariate Data Analyses to Unravel Authenticity

Differences between seven authentic samples of Citrus sinensis var. Valencia peel (albedo and flavedo) and juices from Spain and Uruguay, in addition to a concentrate obtained from Brazil, were investigated by untargeted metabolic profiling. Sixty-six metabolites were detected by nano-liquid chromatography coupled to a high-resolution electrospray-ionization quadrupole time-of-flight mass spectrometer (nLC-ESI-qTOF-MS) belonging to phenolic acids, coumarins, flavonoid glycosides, limonoids, terpenes, and fatty acids. Eleven metabolites were detected for the first time in Citrus sinensis and identified as citroside A, sinapic acid pentoside, apigenin-C-hexosyl-O-pentoside, chrysoeriol-C-hexoside, di-hexosyl-diosmetin, perilloside A, gingerol, ionone epoxide hydroxy-sphingenine, xanthomicrol, and coumaryl alcohol-O-hexoside. Some flavonoids were completely absent from the juice, while present most prominently in the Citrus peel, conveying more industrial and economic prospects to the latter. Multivariate data analyses clarified that the differences among orange parts overweighed the geographical source. PCA analysis of ESI-(-)-mode data revealed for hydroxylinoleic acid abundance in flavedo peel from Uruguay the most distant cluster from all others. The PCA analysis of ESI-(+)-mode data provided a clear segregation of the different Citrus sinensis parts primarily due to the large diversity of flavonoids and coumarins among the studied samples.

Cachrys L. Genus: A Comprehensive Review on Botany, Phytochemistry and Biological Properties

The Cachrys L. genus belongs to the Apiaceae family and it is widely distributed in the Mediterranean basin, with plant species being endemic to southern Europe, Asia, and northern Africa. Different studies, focused on the phytochemical composition of Cachrys spp. and the biological properties of their phytocomplexes, have been reported. These works mostly focused on the essential oils obtained from these plants, and pointed out that Cachrys species are a rich source of coumarins, mainly furanocoumarins. Other phytochemicals, such as terpenes, fatty acids, phytosterols, and flavonoids have been also identified. Moreover, a number of biological properties such as antioxidant, antimicrobial, anti-inflammatory, cytotoxic, and photocytotoxic effects have been assessed. Nevertheless, a review of the chemical and pharmacological properties of this genus is not available in the literature. The aim of this paper is to provide an overview of the reports concerning the identified phytochemicals and the biological effects reported for Cachrys spp., and to offer a comprehensive understanding of the potential of this genus as a source of bioactive compounds. The current taxonomy, the traditional uses, and the toxicological aspects of plants belonging to this genus are also reported, and the future research directions are discussed.

Development of a New Methodology for Dearomative Borylation of Coumarins and Chromenes and Its Applications to Synthesize Boron-Containing Retinoids

Dearomative borylation of coumarins and chromenes via conjugate addition represents a relatively unexplored and challenging task. To address this issue, herein, we report a new and general copper (I) catalyzed dearomative borylation process to synthesize boron-containing oxacycles. In this report, the borylation of coumarins, chromones, and chromenes comprising functional groups, such as esters, nitriles, carbonyls, and amides, has been achieved. In addition, the method generates different classes of potential boron-based retinoids, including the ones with oxadiazole and anthocyanin motifs. The borylated oxacycles can serve as suitable intermediates to generate a library of compounds.

Green Synthesis of Characterized Silver Nanoparticle Using Cullen tomentosum and Assessment of Its Antibacterial Activity

Plants serve as an important source of medicine and provide suitable candidate compounds to produce eco-friendly therapeutic agents. They also represent a source of bio-reducer and stabilizer for the development of nanoparticles for downstream applications. This study focused on the green synthesis of silver nanoparticle (CTAgNP) using Cullen tomentosum (Thunb.) J.W. Grimes acetone extract and the evaluation of the antibacterial activity of the plant extract and biogenic nanoparticles against two Gram-positive bacteria strains, namely Bacillus cereus and Staphylococcus aureus. In addition, the phytochemical profile of C. tomentosum was established using liquid chromatography-mass spectrometry (LC-MS). The antibacterial effect of the extract and CTAgNP was moderate based on the minimum inhibitory concentration (MIC) values obtained. The MIC values of 2.6 mg/mL and 3.1 mg/mL were recorded for C. tomentosum extract against B. cereus and S. aureus, respectively. On the other hand, the CTAgNP had MIC values of 1.5 mg/mL and 2.6 mg/mL against B. cereus and S. aureus, respectively. The nanoparticle exhibited surface charge of -37 ± 7.67 mV and average hydro-dynamic size of 145 nm. X-ray diffraction illustrates that metallic nanoparticles were formed and had a face-centered cubic structure. Microscopic and spectroscopic techniques revealed that the CTAgNP was covered by a protective shell layer constituted of organic compounds originating from the plant extract. The acetone extract of C. tomentosum could be useful to the bio-pharma industries in the large-scale manufacture of nanoparticle-based medications to fight against microbes that constitute a threat to the survival of humanity.

The Journey of a Medicinal Plant throughout Science: Sphaeralcea angustifolia (Cav.) G. Don (Malvaceae)

Using herbal medicine is an ancestral cultural practice among Mexicans. A broad sector of society turns to plants to treat priority health problems, a reality that leads scientists to explore the healing value attributed to them. Advances in the experimental research of Sphaeralcea angustifolia confirmed the anti-inflammatory activity of the species; therefore, an analysis of the scope of these studies is now warranted. As such, this paper is a compendium of the advances published in the scientific literature (from 2004 to 2021) on the anti-inflammatory properties of this plant. The promise offered by the species as a potential therapeutic agent is also considered, without dismissing aspects necessary for the preservation of this resource and its cultural and physical environment. The chemical-pharmacological aspects of the wild plant and its in vitro culture are highlighted. The plant's anti-inflammatory properties support its clinical application as an anti-inflammatory phytopharmaceutical to treat arthritic conditions. The sustained therapeutic potential of S. angustifolia is reinforced by the biotechnological processes designed to conserve the resource, thus contributing to the protection of biodiversity and cultural diversity, aspects distinctive of a megadiverse country such as Mexico.