rutin and 1-1-diphenyl-2-picrylhydrazyl

Antioxidant-directed fractionation of an ethyl acetate extract of Streptomyces sp. TC1 resulted in the isolation of a novel secondary metabolite with an aromatic organofluorine scaffold (1), an atypical tripod-type triallyl phenol (2), and a leucine residue comprised polyamine (3). Their structures were established by comprehensive spectroscopic analysis of 1D and 2D NMR data, and compound 1 was confirmed by (19)F NMR and single-crystal X-ray diffraction studies. The absolute configuration of compound 3 was assigned by comparison of its ECD spectra and quantum chemical ECD calculations. Of these, compound 1 displayed antioxidant and DNA and protein binding properties.

Topics: Antioxidants; Biphenyl Compounds; Crystallography, X-Ray; Drug Screening Assays, Antitumor; Free Radical Scavengers; HCT116 Cells; HeLa Cells; Humans; Hydrocarbons, Fluorinated; Microbial Sensitivity Tests; Molecular Conformation; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Picrates; Propionates; Streptomyces

From an extract of the aerial parts of Dracocephalum ruyschiana, five new flavone tetraglycosides, five new benzyl alcohol glycosides, and 19 known compounds were isolated. The tetraglycosides contain a 7-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→6)]-β-d-glucopyranosyl moiety. The benzyl alcohol glycosides had acyl groups on their glycosyl or aglycone moieties. The compounds were tested for antioxidant activity using DPPH. Although the new compounds were not active, phenylpropanoylquinic acid derivatives were revealed as radical scavengers in D. ruyschiana.

Topics: Antioxidants; Benzyl Alcohol; Biphenyl Compounds; Flavones; Free Radical Scavengers; Glycosides; Lamiaceae; Molecular Structure; Mongolia; Picrates; Plants, Medicinal

Analysis of a methanolic extract of Tagetes lucida leaves has resulted in the isolation of a new flavonol glycoside, quercetagenin 3,4'-dimethyl ether 7-O-beta-D-glucopyranoside (1), two new phenolic acids, 3-(2-O-beta-D-glucopyranosyl-4-methoxyphenyl)propanoic acid (2) and its methylester (3), and known flavonols, aromatic acids, and 7-methoxycoumarin. Using the DPPH degrees test, the extract and some of its constituents showed a significant free-radical-scavenging effect in comparison to alpha-tocopherol and standard flavonols.

Topics: Antioxidants; Biphenyl Compounds; Chromatography, High Pressure Liquid; Flavonoids; Free Radical Scavengers; Glycosides; Guatemala; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Picrates; Plant Leaves; Plants, Medicinal; Spectrophotometry, Ultraviolet; Tagetes; Tocopherols

A new cyclohexenone (1) and a new caffeoyl ester derivative (2), together with the known compounds (-)-isolariciresinol 3-alpha-O-beta-D-glucopyranoside (3), (+)-1-hydroxypinoresinol 1-O-beta-D-glucopyranoside (4), isoacteoside (5), luteolin 4'-O-beta-D-glucopyranoside (6), and indole-3-carboxylic acid (7), were isolated from the leaves of Bauhinia tarapotensis. The structures of these new compounds were determined by spectroscopic data analysis. The antioxidant activities of 1-7 were determined by measuring their free radical scavenging effects, using the 1,1-diphenyl-2-dipicrylhydrazyl free radical (DPPH) and Trolox equivalent antioxidant activity (TEAC) methods, and the coupled oxidation of beta-carotene and linoleic acid. Compounds 3-5 showed good activities in the DPPH and TEAC tests, while compounds 1 and 2 were active in the coupled oxidation of beta-carotene and linoleic acid bioassay.

Topics: Antioxidants; Benzothiazoles; Bepridil; Biphenyl Compounds; Caffeic Acids; Chromans; Chromatography, High Pressure Liquid; Cyclohexanones; Ecuador; Fabaceae; Flavonoids; Free Radical Scavengers; Glucosides; Indoles; Luteolin; Magnetic Resonance Spectroscopy; Molecular Structure; Phenols; Picrates; Plant Leaves; Plants, Medicinal; Sulfonic Acids

Four hydroxyethyl rutosides, 7,3',4'-trihydroxyethyl quercetin, quercetin and a commercial standardized mixture of hydroxyethyl rutosides were investigated on non-enzymatic lipid peroxidation, for hydroxyl radical scavenging activity and interaction with 1,1-diphenyl-2-picrylhydrazyl stable free radical (DPPH). It was found that the tested compounds exhibited a considerable inhibition of microsomal lipid peroxidation. They were less active than the reference compound quercetin, and this was attributed to their structural characteristics. They were also found to be potent hydroxyl radical scavengers and to interact with DPPH. As hydroxyl radical scavengers, they were more potent than the scavengers mannitol and dimethyl sulphoxide. These properties could be considered as a useful and exploitable combination.

Topics: Animals; Bepridil; Biphenyl Compounds; Dimethyl Sulfoxide; Drug Interactions; Female; Flavonoids; Free Radical Scavengers; Hydroxyethylrutoside; Lipid Peroxidation; Microsomes, Liver; Picrates; Quercetin; Rats; Rats, Inbred Strains; Structure-Activity Relationship