benzofurans and 1-1-diphenyl-2-picrylhydrazyl

Chronic diseases such as cancer, diabetes, neurodegenerative and cardiovascular diseases are characterized by an enhanced state of oxidative stress, which may result from the overproduction of reactive species and/or a decrease in antioxidant defenses. The search for new chemical entities with antioxidant profile is still thus an emerging field on ongoing interest. Due to the lack of reviews concerning the antioxidant activity of lichen-derived natural compounds, we performed a review of the antioxidant potential and mechanisms of action of natural compounds isolated from lichens. The search terms "lichens", "antioxidants" and "antioxidant response elements" were used to retrieve articles in LILACS, PubMed and Web of Science published until February 2014. From a total of 319 articles surveyed, 32 met the established inclusion and exclusion criteria. It was observed that the most common isolated compound studied was usnic acid, cited in 14 out of the 32 articles. The most often described antioxidant assays for the study of in vitro antioxidant activity were mainly DPPH, LPO and SOD. The most suggested mechanisms of action were scavenging of reactive species, enzymatic activation and inhibition of iNOS. Thus, compounds isolated from lichens are possible candidates for the management of oxidative stress, and may be useful in the treatment of chronic diseases.

Topics: Antioxidant Response Elements; Antioxidants; Benzofurans; Biphenyl Compounds; Free Radical Scavengers; Humans; Lichens; Neoplasms; Oxidation-Reduction; Oxidative Stress; Picrates

Multi-target drugs can better address the cascade of events involved in oxidative stress and the reduction in cholinergic transmission that occur in Alzheimer's disease than cholinesterase inhibitors alone. We synthesised a series of 3-arylbenzofuranone derivatives and evaluated their antioxidant activity, cholinesterase inhibitory activity, and monoamine oxidase inhibitory activity. 3-Arylbenzofuranone compounds exhibit good antioxidant activity as well as selective acetylcholinesterase inhibitory activity. The IC

Topics: Acetylcholinesterase; Alzheimer Disease; Animals; Anti-Anxiety Agents; Antioxidants; Benzofurans; Biphenyl Compounds; Cholinesterase Inhibitors; Dose-Response Relationship, Drug; Humans; Models, Molecular; Molecular Structure; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Picrates; Rats; Rats, Wistar; Structure-Activity Relationship

Thirty benzofuran-2-yl(phenyl)methanones 1-30 were synthesized and characterized their structures by spectroscopic techniques. Substituted phenacyl bromide and different derivatives of 2-hydroxy-benzaldehyde treated in the presence of anhydrous K

Topics: alpha-Amylases; Benzofurans; Benzothiazoles; Biphenyl Compounds; Dose-Response Relationship, Drug; Enzyme Inhibitors; Free Radical Scavengers; Kinetics; Molecular Docking Simulation; Molecular Structure; Picrates; Structure-Activity Relationship; Sulfonic Acids

A series of (3-hydroxy-4-pyridinone)-benzofuran hybrids have been developed and studied as potential multitargeting drugs for Alzheimer's disease (AD). Their design envisaged mainly to mimic the donepezil drug, a marketed inhibitor of acetylcholinesterase (AChE), and to endow the conjugate molecules with extra-properties such as metal chelation, radical scavenging and inhibition of amyloid peptide (Aβ) aggregation. Thus, a set of eleven new hybrid compounds was developed and evaluated for chemical and biological properties, in solution and in neuronal cell environment. The results are discussed in terms of the type of substituents on both main moieties and the linker size. The closest similarity with donepezil, in terms of AChE inhibitory activity, was obtained for the O-benzyl-hydroxypyridinone hybrids containing a 2-methylene linker, although still less active than the drug. However, the free-hydroxypyridinone hybrids present higher activity for the Aβ aggregation inhibition, metal chelating capacity and radical scavenging activity. Overall, some compounds demonstrated capacity to exert a multiple action by hitting three- (7d) or four- (8d, 8f) pathophysiological targets of AD. Furthermore, the compounds showed neuroprotective effects in neuronal cells subjected to model stressors of AD, but not significant dependence on the substituent groups. Importantly, the compounds evidenced drug-likeness properties, including good membrane permeability.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Benzofurans; Biphenyl Compounds; Cholinesterase Inhibitors; Copper; Free Radical Scavengers; Iron; Iron Chelating Agents; Molecular Docking Simulation; Neuroprotective Agents; Peptide Fragments; Picrates; Protein Multimerization; Pyridones

The present work aimed to synthesise promising antioxidant compounds as a valuable alternative to the currently expensive and easily degradable molecules that are employed as stabilizers in industrial preparation. Taking into account our experience concerning domino Friedel-Crafts/lactonization reactions, we successfully improved and extended the previously reported methodology toward the synthesis of 3,3-disubstituted-3

Topics: Acetonitriles; Alkylation; Antioxidants; Benzofurans; Biphenyl Compounds; Electrochemistry; Kinetics; Methanol; Oxidation-Reduction; Phenols; Picrates; Regression Analysis; Solvents

(-)-Epigallocatechin-3-O-gallate (EGCG), the major catechin present in green tea, exhibits potent antioxidant activity. We thereby investigated the presence of unknown components bearing the (-)-epigallocatechin (EGC) moiety in fresh tea leaf samples. Initially, liquid chromatography tandem mass spectrometry (LC-MS/MS) was employed to examine fresh tea leaves of the Yabukita, the most popular tea cultivar in Japan, which suggested the presence of the EGC phenylpropanoid derivatives, (-)-epigallocatechin-3-O-p-coumaroate (EGCpCA) and (-)-epigallocatechin-3-O-caffeoate (EGCCA). The structures of the detected EGCpCA and EGCCA were then confirmed by LC-MS/MS using synthesized EGCpCA and EGCCA as standards. In addition, EGCpCA and EGCCA were evaluated for their antioxidant activity in the ORAC (oxygen radical antioxidant capacity) and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging assays, where EGCCA (8.60μmolTE/μmol, TE=Trolox equivalents) exhibited a stronger antioxidant activity than EGCG (5.52μmolTE/μmol) in the ORAC assay. Finally, EGCpCA and EGCCA were quantitated in several tea leaf samples using LC-MS/MS, and it was found that these compounds were present in lower quantities (EGCpCA, 16.8-345.8μg/g, EGCCA, 4.3-75.1μg/g in the dry tea leaves) than the major catechins. In this study, we found the potent antioxidant EGCCA using LC-MS/MS and revealed its wide existence in various tea leaves.

Topics: Antioxidants; Benzofurans; Biphenyl Compounds; Caffeic Acids; Calibration; Camellia sinensis; Catechin; Chromatography, Liquid; Molecular Structure; Oxygen Radical Absorbance Capacity; Picrates; Plant Leaves; Reference Standards; Reproducibility of Results; Structure-Activity Relationship; Tandem Mass Spectrometry

There is a worldwide ongoing investigation for novel natural constituents with cytotoxic and antioxidant properties. The aim of this study was to investigate chemical profile and stated biological activities of the supercritical CO2 extract (SCE) of old man's beard compared to the extracts obtained using the conventional techniques (Soxhlet extracts and macerate). The most abundant compound identified was usnic acid, which content was inversely proportional to the polarity of the solvent used and was the highest in the SCE, which was the sample revealing the highest cytotoxic activity in tested tumor cell lines (B16 mouse melanoma and C6 rat glioma), with lower IC50 values compared to pure usnic acid. Further investigations suggested both SCE and usnic acid to induce apoptosis and/or autophagy in B16 and C6, indicating higher cytotoxicity of SCE to be related to the higher degree of ROS production. A good correlation of usnic acid content in the extracts and their antioxidant capacity was established, extricating SCE as the most active one. Presented results support further investigations of SCE of old man's beard as a prospective therapeutic agent with potential relevance in the treatment of cancer and/or in oxidative stress-mediated conditions.

Topics: Animals; Antineoplastic Agents, Phytogenic; Antioxidants; Apoptosis; Autophagy; Benzofurans; Biphenyl Compounds; Carbon Dioxide; Cell Cycle; Cell Line, Tumor; Chromatography, Supercritical Fluid; Mice; Oxidation-Reduction; Picrates; Rats; Usnea

The antioxidant activities and total phenolic content of fermented Salvia miltiorrhiza with fungus Geomyces luteus were investigated. The results revealed that G. luteus fermentation could significantly improve the antioxidant activity and total phenolic content of S. miltiorrhiza. The main antioxidant constituents were characterized by spectroscopic analysis as salvianolic acids. High-performance liquid chromatography (HPLC) quantification also showed the enhanced content of salvianolic acid B after fermentation. The present study suggests that G. luteus fermentations are effective in the S. miltiorrhiza salvianolic acids' enrichment process.

Topics: Alkenes; Antioxidants; Ascomycota; Benzofurans; Biphenyl Compounds; Chromatography, High Pressure Liquid; Drugs, Chinese Herbal; Fermentation; Phenols; Picrates; Polyphenols; Salvia miltiorrhiza; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared

Salvianolic acid A (Sal A) was considered to be the compound with highest activity in Salvia miltiorrhiza (danshen). Due to its low content in raw materials, many studies reported its preparation from salvianolic acid B (Sal B). However, the process of this transformation is still unknown. Our objective was to find the chemical change of the transformation from Sal B to Sal A. The results showed that Sal B was hydrolyzed to lithospermic acid (LA) first, and the latter was transformed into Sal A in thermal aqueous solution. The radical scavenging ability of Sal A, Sal B, and LA was tested through DPPH, and Sal A showed higher radical elimination ability compared to Sal B and LA. In vitro liver damage was induced by CCl4 in human hepatic WRL68 cell line. Sal A, Sal B, and LA showed liver protective ability in a dose-dependent manner, while Sal A possessed a much higher ability compared to Sal B and LA.

Topics: Antioxidants; Benzofurans; Biphenyl Compounds; Caffeic Acids; Carbon Tetrachloride; Cell Line; Chemical and Drug Induced Liver Injury; Depsides; Drugs, Chinese Herbal; Hot Temperature; Humans; In Vitro Techniques; Lactates; Liver; Phytotherapy; Picrates; Salvia miltiorrhiza; Water

Gerbera anandria (Compositae) was extracted with 75% ethanol and the residue was fractionated using light petroleum, chloroform and ethyl acetate. The constituents of the extracts were separated by column chromatography employing solvents of different polarity. Column chromatography of the light petroleum fraction resulted in the isolation of methyl hexadecanoate, while the chloroform fraction afforded xanthotoxin, 2-hydroxy-6-methylbenzoic acid, 7-hydroxy-1(3H)-isobenzofuranone, a mixture of β-sitosterol and stigmasterol, and 8-methoxysmyrindiol and the ethyl acetate fraction gave gerberinside, apigenin-7-O-β-d-glucopyranoside and quercetin. A new coumarin, 8-methoxysmyrindiol, was found. The chemical structures of the isolated compounds were established by MS and NMR (HSQC, HMBC). Free radical scavenging and cytotoxic activities of crude extracts and 8-methoxysmyrindiol were further investigated. The ethyl acetate phase exerted the strongest DPPH free radical scavenging activity in comparison to the other fractions. The coumarin 8-methoxysmyrindiol demonstrated cytotoxicity against multiple human cancer cell lines, with the highest potency in HepG2 cells.

Topics: Antineoplastic Agents, Phytogenic; Asteraceae; Benzoates; Benzofurans; Biphenyl Compounds; Cell Line, Tumor; Cell Survival; Decanoates; Flavonoids; Free Radical Scavengers; Humans; Methoxsalen; Phytosterols; Picrates; Plant Extracts; Solvents

Coumestan is a natural tetracycle with a C═C bond shared by a coumarin moiety and a benzofuran moiety. In addition to the function of the hydroxyl group on the antioxidant activity of coumestan, it is worth exploring the influence of the oxygen-abundant scaffold on the antioxidant activity as well. In this work, seven coumestans containing electron-withdrawing and electron-donating groups were synthesized to evaluate the abilities to trap 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS(•+)), 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH), and galvinoxyl radical, respectively, and to inhibit the oxidations of DNA mediated by (•)OH, Cu(2+)/glutathione (GSH), and 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH), respectively. It was found that all of the coumestans used herein can quench the aforementioned radicals and can inhibit (•)OH-, Cu(2+)/GSH-, and AAPH-induced oxidations of DNA. In particular, substituent-free coumestan exhibits higher ability to quench DPPH and to inhibit AAPH-induced oxidation of DNA than Trolox. In addition, nonsubstituted coumestan shows a similar ability to inhibit (•)OH- and Cu(2+)/GSH-induced oxidations of DNA relative to that of Trolox. The antioxidant effectiveness of the coumestan can be attributed to the lactone in the coumarin moiety and, therefore, a hydroxyl group may not be a necessary functional group for coumestan to be an antioxidant.

Topics: Amidines; Antioxidants; Benzofurans; Biphenyl Compounds; Coumarins; DNA; Glutathione; Hydroxyl Radical; Oxidation-Reduction; Picrates

The effects of salvianolic acid B (Sal B) decoction on antioxidative activities were evaluated. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, Fe(2+)-chelating activity, reducing power, and total phenolic content of the Sal B-decocted solutions did not change significantly after decoction in an aqueous solution. However, the formation of cholesteryl ester hydroperoxide (CE-OOH) in rat blood plasma containing the Sal B-decocted solutions was more effectively inhibited than that of plasma containing the Sal B solution, regardless of the decoction time. In addition, the accumulation of CE-OOH in rat plasma after oral administration of the Sal B-decocted solutions was more effectively suppressed than when the Sal B solution was administered, considering the lag time. It is likely that the decoction was partly responsible for the increased antioxidant activity in blood plasma. Therefore, the Sal B-decocted solution may contribute more to antioxidant defense in blood than a Sal B solution that is not decocted.

Topics: Administration, Oral; Animals; Antioxidants; Benzofurans; Biphenyl Compounds; Chelating Agents; Cholesterol Esters; Copper; Ions; Male; Oxidation-Reduction; Phenols; Picrates; Plant Extracts; Plant Preparations; Rats; Rats, Sprague-Dawley; Salvia

In this study, we aimed to elucidate the antioxidant capacity of Eisenia bicyclis and evaluated its antioxidant activity using various assay systems such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, 2,2-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, reducing power ability, and content of total polyphenol. Among all the performed experiments, the ethyl acetate fraction of E. bicyclis exhibited higher antioxidant activities. From this finding, isolation and purification were performed on the ethyl acetate fraction and identified dieckol and phlorofucofureoeckol-A by spectroscopic analyses including FAB-mass in the negative mode, (1) H NMR, (13) C NMR, (1) H-(1) H COSY, HMQC, and HMBC spectra. Interestingly, ABTS radical scavenging activities of dieckol and phlorofucofuroeckol showed strong effects of 65.36% and 70.38% at a concentration of 50 μg/mL, respectively. DPPH radical scavenging and reducing power abilities were increased in a dose-dependent manner at various concentrations. These results suggest that dieckol and phlorofucofuroeckol-A of E. bicyclis may play an important role in protection from oxidative stress involving reactive oxygen species and may contribute to the development of new bio products, for example, a useful preservative to improve food quality and a drug for various oxidative damage-associated diseases. Practical Application: The results suggest that dieckol and phlorofucofuroeckol-A can be utilized as a natural source for potential application of antioxidant in food industry and drug for oxidative damage-associated diseases.

Topics: Antioxidants; Benzofurans; Benzothiazoles; Biphenyl Compounds; Dioxins; Free Radical Scavengers; Magnetic Resonance Spectroscopy; Oxidative Stress; Phaeophyceae; Picrates; Polyphenols; Reactive Oxygen Species; Solvents; Sulfonic Acids

Eight new dihydrobenzofuran neolignans, pinnatifidanin C I-VIII (1-8), together with two known analogs (9-10) were isolated from the seeds of Crataegus pinnatifida. Their structures were elucidated by spectroscopic analyses, especially 1D, 2D NMR and CD spectra. The cytotoxic activities of all isolates against human cancer cell lines were assayed, and most interestingly, compound 10 revealed preferred cytotoxicity on the HT-1080 cell line and displayed much stronger inhibitory activity (IC50=8.86 μM) compared with positive control 5-fluorouracil (IC50=35.62 μM). Meanwhile, antioxidant activities of all the isolates were evaluated using 2,2-diphenyl-1-pikrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) assays, and the results showed that most of the isolates exhibited potent antioxidant activity.

Topics: Antineoplastic Agents, Phytogenic; Antioxidants; Benzofurans; Benzothiazoles; Biphenyl Compounds; Cell Line, Tumor; Crataegus; Humans; Inhibitory Concentration 50; Lignans; Molecular Structure; Neoplasms; Phytotherapy; Picrates; Plant Extracts; Seeds; Sulfonic Acids

Buglossoides purpureocaerulea is a little-known plant used in the folk tradition for the preparation of a decoction in Sud, Italy, where it is appreciated for its beneficial effects on liver diseases. These properties may be due to the presence of antioxidant compounds. This study presents the phenolic characterisation and the antioxidant activity (AA) of B. purpureocaerulea extracts obtained by decoction, ethanol infusion and ethanol and methanol macerations. Total phenols ranged between 69 and 100 mg g(-1 ) dry weight (DW). The main compounds were: rosmarinic acid, caffeic acid, lithospermic acid and salvianolic acid C. The extracts showed a good AA, particularly high for the decoction (142-283 µmol TE g(-1) DW; TE, Trolox equivalent) and ethanol maceration extract (214-364 µmol TE g(-1) DW) when determined by DPPH and ferric reducing antioxidant power test, respectively.

Topics: Alkenes; Antioxidants; Benzofurans; Biphenyl Compounds; Boraginaceae; Caffeic Acids; Cinnamates; Depsides; Free Radical Scavengers; Picrates; Plant Extracts; Polyphenols; Rosmarinic Acid

Two novel phlorotannins with a molecular weight of 974, temporarily named 974-A and 974-B, were isolated from the polyphenol powder prepared from the edible marine brown alga Ecklonia kurome Okamura, and their chemical structures were determined by spectroscopic method. The isolated yield of the total of 974-A and 974-B was approximately 4% (w/w) from the polyphenol powder. In 974-A, the carbon at the C2' position in the A ring of phlorofucofuroeckol-A forms a C-C bond with the carbon at the C2″ position of the C ring of triphloretol-B, while in 974-B, phlorofucofuroeckol-B and triphloretol-B form a C-C bond in the same manner as in 974-A. These structures were supported by high resolution-MS/MS data. To evaluate the antioxidant activities, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and intracellular radical scavenging assay, using 2',7'-dichlorofluorescin diacetate (DCFH-DA), were performed for 974-A, 974-B, and four known phlorotannins. The results of the DPPH assay showed that the IC(50) values of 974-A, 974-B, phlorofucofuroeckol-A, and dieckol were significantly smaller than those of phlorofucofuroeckol-B, phloroglucinol, α-tocopherol, and ascorbic acid. Furthermore, the DCFH-DA assay suggested that 974-A, 974-B, and dieckol reduce intracellular reactive oxygen species most strongly among the tested compounds.

Topics: alpha-Tocopherol; Animals; Antioxidants; Ascorbic Acid; Benzofurans; Biphenyl Compounds; Cell Line; Cell Line, Tumor; Dioxins; Fluoresceins; Free Radical Scavengers; Humans; Mass Spectrometry; Mice; Phaeophyceae; Phloroglucinol; Picrates; Polyphenols; Tannins

The chemical composition of the essential oil of Petasites albus (known as 'Baba Adam' in Iran) was investigated by capillary gas chromatography and gas chromatography-mass spectrometry for the first time. Twenty components were identified, accounting for 99.7% of the oil composition. The major compounds were euparin (73%), α-eudesmol (13.2%) and β-selinene (4.5%). Euparin, the main component of the essential oil, was isolated and characterised by spectroscopic techniques. The antioxidant activities of the essential oil and euparin were evaluated by using the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay and are shown to exhibit a moderate antioxidant activity.

Topics: Antioxidants; Benzofurans; Biphenyl Compounds; Gas Chromatography-Mass Spectrometry; Iran; Molecular Structure; Oils, Volatile; Petasites; Picrates; Plant Components, Aerial; Plant Oils; Plants, Medicinal; Sesquiterpenes, Eudesmane; Tetrahydronaphthalenes

Antioxidants could be promising agents for management of oxidative stress-related diseases. New biologically active compounds, belonging to a rare class of natural lignans with antiangiogenic, antitumoral and DNA intercalating properties, have been recently synthesized. These compounds are benzo[kl]xanthene lignans (1,2) and dihydrobenzofuran neolignans (3,4). The radical scavenging and chain-breaking antioxidant activities of compounds 1-4 were studied by applying different methods: radical scavenging activity by DPPH rapid test, chain-breaking antioxidant activity and quantum chemical calculations. All studied compounds were found to be active as DPPH scavengers but reaction time with DPPH and compounds' concentrations influenced deeply the evaluation. The highest values of radical scavenging activity (%RSAmax) and largest rate constants for reaction with DPPH were obtained for compounds 2 and 3. Comparison of %RSAmax with that of standard antioxidants DL-α-tocopherol (TOH), caffeic acid (CA) and butylated hydroxyl toluene (BHT) give the following new order of %RSA max: TOH (61.1%) > CA (58.6%) > 3 (36.3%) > 2 (28.1%) > 4 (6.7%) > 1 (3.6%) = BHT (3.6%). Chain-breaking antioxidant activities of individual compounds (0.1-1.0 mM) and of their equimolar binary mixtures (0.1 mM) with TOH were determined from the kinetic curves of lipid autoxidation at 80 °C. On the basis of a comparable kinetic analysis with standard antioxidants a new order of the antioxidant efficiency (i.e., protection factor, PF) of compounds 1-4 were obtained: 2 (7.2) ≥ TOH (7.0) ≥ CA (6.7) > 1 (3.1) > 3 (2.2) > ferulic acid FA (1.5) > 4 (0.6); and of the antioxidant reactivity (i.e. inhibition degree, ID): 2 (44.0) >> TOH (18.7) >> CA (9.3) >> 1 (8.4) > 3 (2.8) > FA (1.0) > 4 (0.9). The important role of the catecholic structure in these compounds, which is responsible for the high chain-breaking antioxidant activity, is discussed and a reaction mechanism is proposed. Higher oxidation stability of the lipid substrate was found in the presence of equimolar binary mixtures 2 + TOH, 3 + TOH and 4 + TOH. However, an actual synergism was only obtained for the binary mixtures with compounds 3 and 4. The geometries of compounds and all possible phenoxyl radicals were optimized using density functional theory. For description of the scavenging activity bond dissociation enthalpies (BDE), HOMO energies and spin densities were employed. The best correlation between theoretical and experimental d

Topics: alpha-Tocopherol; Antioxidants; Benzofurans; Biphenyl Compounds; Butylated Hydroxytoluene; Caffeic Acids; Free Radical Scavengers; Hot Temperature; Kinetics; Lignans; Lipids; Oxidation-Reduction; Phenols; Picrates; Quantum Theory; Solutions; Structure-Activity Relationship; Thermodynamics; Xanthenes

Two new compounds, (2S,3R)-methyl 7-hydroxy-2-(4-hydroxy-3-methoxy-phenyl)-3-(hydroxymethyl)-2,3-dihydrobenzofuran-5-carboxylate (1) and (4R,5S)-5-(3-hydroxy-2,6-dimethylphenyl)-4-isopropyldihydrofuran-2-one (2), tentatively named norcurlignan and limlactone, respectively, were isolated from Liriope muscari, together with the known compound (-)-pinoresinol (3). The structures of these compounds were elucidated and characterized on the basis of 1D NMR, 2D NMR, CD and MS data. The in vitro antioxidant activities of compounds 1-3 were assessed by the DPPH and ABTS scavenging methods.

Topics: Benzofurans; Benzothiazoles; Biphenyl Compounds; Chromatography, Gel; Free Radical Scavengers; Free Radicals; Furans; Lignans; Liriope Plant; Magnetic Resonance Spectroscopy; Medicine, Chinese Traditional; Molecular Conformation; Molecular Structure; Picrates; Sulfonic Acids

Phytochemical study of the methanol extract of Artocarpus altilis resulted in the isolation of a new prenylated aurone, artocarpaurone (1), together with eight known compounds including two prenylated chalcones (2 and 3), three prenylated flavanones (4-6), and three triterpenes (7-9). The structure of 1 was elucidated as 6-hydroxy-2-[8-hydroxy-2-methyl-2-(4-methyl-3-pentenyl)-2H-1-benzopyran-5-ylmethylene]-3(2H)-benzofuranone by spectroscopic methods including 1D and 2D NMR spectra and FT-ICR-MS. Compound 1 showed moderate nitric oxide radical scavenging activity, whereas 2 and 3 had moderate 2,2-diphenyl-1-picrylhydrazyl radical scavenging effect, compared with the positive control (+)-catechin.

Topics: Artocarpus; Benzofurans; Biphenyl Compounds; Catechin; Molecular Structure; Picrates

The aim of this study was to investigate the chemical composition of acetone extracts of the lichens Toninia candida and Usnea barbata and in vitro antioxidant, antimicrobial, and anticancer activities of these extracts together with some of their major metabolites. The chemical composition of T. candida and U. barbata extracts was determined using HPLC-UV analysis. The major phenolic compounds in these extracts were norstictic acid (T. candida) and usnic acid (U. barbata). Antioxidant activity was evaluated by free radical scavenging, superoxide anion radical scavenging, reducing power and determination of total phenolic compounds. Results of the study proved that norstictic acid had the largest antioxidant activity. The total content of phenols in the extracts was determined as the pyrocatechol equivalent. The antimicrobial activity was estimated by determination of the minimal inhibitory concentration using the broth microdilution method. The most active was usnic acid with minimum inhibitory concentration values ranging from 0.0008 to 0.5 mg/mL. Anticancer activity was tested against FemX (human melanoma) and LS174 (human colon carcinoma) cell lines using the microculture tetrazolium test. Usnic acid was found to have the strongest anticancer activity towards both cell lines with IC(50) values of 12.72 and 15.66 μg/mL.

Topics: Anti-Infective Agents; Antioxidants; Ascomycota; Bacteria; Benzofurans; Biphenyl Compounds; Cell Cycle; Cell Line, Tumor; Cell Survival; Fungi; Humans; Inhibitory Concentration 50; Lactones; Lichens; Microbial Sensitivity Tests; Molecular Structure; Phenols; Picrates; Salicylates; Usnea

Five known isocoumarins, monocerin (1), derivative 2, and fusarentin derivatives 3-5, and a new phthalide (6) were isolated from the endophytic fungus Colletotrichum sp. 2 selectively exhibited cytotoxic activity toward the HepG2 cell line. Compounds 2 and 4 scavenged 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals (IC(50) values of 23.4 and 16.4 μM, respectively) and inhibited superoxide anion radical formation (IC(50) values of 52.6 and 4.3 μM, respectively). The C-7 hydroxyl group in 2 and 4 might be important for radical scavenging activities. Isocoumarins 1-3 and phthalide 6 showed potent antioxidant activity.

Topics: Antineoplastic Agents; Antioxidants; Aromatase Inhibitors; Benzofurans; Biphenyl Compounds; Colletotrichum; Drug Screening Assays, Antitumor; Free Radical Scavengers; Hep G2 Cells; HL-60 Cells; Humans; Isocoumarins; Lactones; Molecular Structure; Picrates; Piper; Structure-Activity Relationship; Thailand

Cladonia clathrata Ahti & L. Xavier-Filho (Cladoniaceae) is a lichen; several Cladonia species extracts have been used for various remedies in folk medicine. In order to evaluate the actions of this lichen, studies were performed on antinociceptive, anti-inflammatory, and antioxidant activities. The hydroalcoholic extract (HE) of C. clathrata stems was used in the following experiments. Oral treatment with the HE of C. clathrata elicited inhibitory activity (p < 0.001) on acetic acid-induced abdominal writhes at 100 (47.2%), 200 (47.2%), and 400 mg/kg (86.4%), and reduced the formalin-induced nociception on both the neurogenic (400 mg/kg, p < 0.01) and inflammatory phases (200 and 400 mg/kg, p < 0.01). It was not associated with non-specific effects, such as muscle relaxation or sedation. The HE reduced the carrageenan-induced edema formation at 100, 200, and 400 mg/kg (p < 0.05) and inhibited neutrophil migration into the peritoneal cavity at 400 mg/kg (p < 0.001). The HE of C. clathrata reacted with the DPPH radical and reduced the same by 50.19%, and exhibited an IC(50) value of 69.25 +/- 0.65 mug/mL. The HE of C. clathrata stems shows antinociceptive and anti-inflammatory activities, with a moderate antioxidant potential.

Topics: Analgesics; Animals; Anti-Inflammatory Agents; Antioxidants; Ascomycota; Benzofurans; Biphenyl Compounds; Carrageenan; Drug Evaluation, Preclinical; Lichens; Mice; Motor Activity; Neutrophil Infiltration; Pain Measurement; Picrates; Rats; Rats, Wistar

A series of 2'-hydroxy-chalcones and their oxidative cyclization products, aurones, have been synthesized and tested for their antioxidant and lipoxygenase inhibitory activity. The natural product aureusidin (31) was synthesized in high yield by a new approach. An extensive structure-relationship study was performed and revealed that several chalcones and aurones possess an appealing pharmacological profile combining high antioxidant and lipid peroxidation activity with potent soybean LOX inhibition.

Topics: Antioxidants; Benzofurans; Biphenyl Compounds; Chalcones; Linoleic Acid; Lipoxygenase; Lipoxygenase Inhibitors; Magnetic Resonance Spectroscopy; Mass Spectrometry; Picrates

The radical scavenging activity of maritimetin and a series of synthetic aurones has been studied by using density functional theory with the B3LYP exchange correlation functional. The computation of various molecular descriptors that could assist the elucidation of hydrogen atom and electron donating ability of the selected compounds was carried out in the gas phase and in the liquid phase (benzene, methanol, water) with the aid of IEF-PCM. For reasons of comparison a series of simple phenols of known activity were also included in the study. The results are discussed with regards to the structure-activity relationship principles of flavonoids and in particular to the capacity of the selected aurones to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH(*)) and superoxide anion (O(2)(-*)) radicals. The O-H bond dissociation enthalpy (BDE) seems to be the most proper parameter to characterize the antiradical properties of the studied compounds. The hydroxylation pattern in ring B defines the order of activity, while the extended conjugation and especially the presence of a catechol moiety in ring A are responsible for the high activity observed experimentally for the selected aurones.

Topics: Benzofurans; Biphenyl Compounds; Catechols; Drug Industry; Electron Transport; Flavonoids; Food Industry; Free Radical Scavengers; Hydrazines; Hydrogen; Picrates; Quantum Theory; Solvents; Superoxides

Danshensu (3-(3,4-dihydroxyphenyl) lactic acid) and salvianolic acid B, two natural phenolic acids of caffeic acid derivatives isolated from Salvia miltiorrhiza root of the most widely used traditional Chinese medicine for the treatment of various cardiovascular diseases, have been reported to have potential protective effects from oxidative injury. To better understand their biological functions, the in vitro radical scavenging and antioxidant activities of danshensu and salvianolic acid B were evaluated along with vitamin C. Both danshensu and salvianolic acid B exhibited higher scavenging activities against free hydroxyl radicals (HO()), superoxide anion radicals (O(2)(-)), 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radicals and 2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radicals than vitamin C. In contrary, danshensu and salvianolic acid B showed weaker iron chelating and hydrogen peroxide (H(2)O(2)) scavenging activities than vitamin C. As expressed as vitamin C equivalent capacity (VCEAC), the relative VCEAC values (mg/100ml) were in the order of salvianolic acid B (18.59) > danshensu (12.89) > vitamin C (10.00) by ABTS radical assay. The protective efficiencies against hydrogen peroxide induced human vein vascular endothelial cell damage were correlated with their antioxidant activities. Analysis of structure-activity relationship of these two compounds showed that the condensation and conjugation of danshensu and caffeic acid appears important for antioxidant activity. These results indicated that danshensu and salvianolic acid B are efficient radical scavengers and antioxidants, and salvianolic acid B is superior to danshensu. Their radical scavenging and antioxidant properties might have potential applications in food and healthcare industry.

Topics: Antioxidants; Ascorbic Acid; Benzofurans; Benzothiazoles; Biphenyl Compounds; Cell Survival; Chelating Agents; Endothelial Cells; Ferrous Compounds; Free Radical Scavengers; Humans; Hydrogen Peroxide; Hydroxyl Radical; Lactates; Oxidants; Picrates; Plant Roots; Salvia; Sulfonic Acids; Tetrazolium Salts; Thiazoles

A phytochemical investigation on the aerial parts of Lindelofia stylosa has resulted in the isolation of seven phenyl propanoids. This includes three analogs of lithospermic acid, along with rosmarinic acid and its ester derivatives. Compound 1 was identified as a new natural product. These compounds were studied for their antioxidant properties.

Topics: Antioxidants; Benzofurans; Biphenyl Compounds; Boraginaceae; Chemical Phenomena; Chemistry, Physical; Chromatography, High Pressure Liquid; Free Radical Scavengers; Heterocyclic Compounds, 4 or More Rings; Iron Chelating Agents; Magnetic Resonance Spectroscopy; Picrates; Spectrometry, Mass, Fast Atom Bombardment; Spectrophotometry, Ultraviolet; Superoxides

3',4',6,7-Tetrahydroxyaurone (1a), an aurone isolated from Bidens frondosa, and five analogues (1b-1f) were synthesized from pyrogallol in three steps. The antioxidative activity of 1a-1f was determined by the superoxide free radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging methods.

Topics: Antioxidants; Benzofurans; Bidens; Biphenyl Compounds; Hydrazines; Picrates; Pyrogallol; Superoxides

A sulfated emodin glucoside, emodin 8-O-beta-D-glucopyranosyl-6-O-sulfate (1), was isolated from the roots of Rheum emodi in an investigation of the active constituents of this Nepalese medicinal plant, and its structure was determined by spectroscopic and chemical methods. Additionally, two rare auronols, carpusin (2) and maesopsin (3), besides other anthraquinones and phenolics, were isolated and identified. Compounds 2 and 3 showed significant antioxidant activity in the DPPH assay, while chrysophanol, physcion, and emodin and their 8-O-glucosides were found to be inactive.

Topics: Anthraquinones; Antioxidants; Benzofurans; Biphenyl Compounds; Glycosides; Inhibitory Concentration 50; Molecular Structure; Nepal; Nuclear Magnetic Resonance, Biomolecular; Picrates; Plant Roots; Plants, Medicinal; Rheum

Bioassy-directed fractionation of a culture broth of Penicillium citrinum F5 led to the isolation of a novel antioxidant 2,3,4-trimethyl-5,7-dihydroxy-2,3-dihydrobenzofuran (1), together with gentisic acid (2), and their structures were determined on the basis of spectroscopic data. In the 1,1-diphenyl-picryl-hydrazyl (DPPH) assay system, compounds 1 and 2 showed free radical scavenging activity with IC(20) values of 10.39 and 4.26 microM, respectively.

Topics: Antioxidants; Benzofurans; Biphenyl Compounds; Chromatography, High Pressure Liquid; Free Radical Scavengers; Inhibitory Concentration 50; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Penicillium; Picrates; Taiwan

Salvia miltiorrhiza is a traditional Chinese medicine which has been well documented for its anti-cancer effects. Based on the structure of danshinone, one of the active compounds derived from Salvia miltiorrhiza, we synthesized a simplified phenolic analog, S-3-1, and tried to explore its possible actions in preventing the development of cancer. With the Ames test, S-3-1 was found to efficiently suppress the mutagenicity of benzo[alpha]pyrene. This result is consistent with the inhibitory effect of S-3-1 on the activation of benzo[alpha]pyrene by hepatic microsomal enzymes. Besides the anti-initiation effects, S-3-1 could significantly inhibit the croton oil-induced increase of mouse skin epithermal ornithine decarboxylase activity. Moreover, S-3-1 quenched both superoxide and hydroxyl free radicals whereas it inhibited lipid peroxidation in the in vitro model. These results suggest that S-3-1 might act as anti-initiation and anti-promotion agents through reversing the biochemical alterations induced by carcinogen during carcinogenesis. Therefore, we further investigated the effects of S-3-1 on carcinogenesis. In vitro, S-3-1 inhibited the benzo[alpha]pyrene-induced transformation of V79 Chinese hamster lung fibroblasts. At 10-40 mg/kg, S-3-1 was found to inhibit the development of DMBA/croton oil-induced skin papilloma in mice through decreasing the incidence of papilloma, prolonging the latent period of tumor occurrence and reducing tumor number per mouse in a dose-dependent manner. We concluded from this study that S-3-1 might be developed as a new chemopreventive drug.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Anticarcinogenic Agents; Benzo(a)pyrene; Benzofurans; Bepridil; Biphenyl Compounds; Cell Transformation, Neoplastic; Cells, Cultured; Cricetinae; Croton Oil; Cysteine; Disease Models, Animal; Dose-Response Relationship, Drug; Drugs, Chinese Herbal; Epithelial Cells; Fibroblasts; Free Radical Scavengers; Hypoxanthine; In Vitro Techniques; Iron; Lipid Peroxidation; Lung; Male; Medicine, Chinese Traditional; Mice; Mice, Inbred ICR; Microsomes, Liver; Molecular Structure; Mutagens; Ornithine; Ornithine Decarboxylase; Papilloma; Pentetic Acid; Phenanthrenes; Picrates; Plants, Medicinal; Rats; Salmonella; Skin; Skin Neoplasms; Spectrometry, Mass, Electrospray Ionization; Structure-Activity Relationship; Xanthine Oxidase