echinochrome-a and 1-1-diphenyl-2-picrylhydrazyl

echinochrome-a has been researched along with 1-1-diphenyl-2-picrylhydrazyl* in 2 studies

Other Studies

2 other study(ies) available for echinochrome-a and 1-1-diphenyl-2-picrylhydrazyl

Article	Year
Echinamines A and B, first aminated hydroxynaphthazarins from the sea urchin Scaphechinus mirabilis. Journal of natural products, 2005, Volume: 68, Issue:9 Two new spinochromes, echinamines A (1) and B (2), were isolated from the sea urchin Scaphechinus mirabilis. Compounds 1 and 2 represent the first examples of natural polyhydroxynaphthazarins with a primary amine group. The structures of 1 and 2 were established by analysis of spectroscopic data and synthesis of their dimethyl ethers. Topics: Animals; Biphenyl Compounds; Japan; Molecular Structure; Naphthoquinones; Nuclear Magnetic Resonance, Biomolecular; Picrates; Sea Urchins	2005
Echinochrome, a naturally occurring iron chelator and free radical scavenger in artificial and natural membrane systems. Life sciences, 2005, Jan-07, Volume: 76, Issue:8 Echinochrome, or 6-ethyl-2,3,5,7,8-pentahydroxy-1,4-naphthoquinone, possesses cardioprotective activity, and diminishes the myocardial ischemia/reperfusion injury that is known to be accompanied by free-radical oxidative damage and calcium overload. In this study, we investigated the lipophilicity of echinochrome, its ability to inhibit free-radical oxidation both in the bulk organic phase and in an artificial membrane system (liposomes), and to prevent the ferrous/ascorbate-induced leakage of calcium from the isolated sarcoplasmic reticulum (SR) of rabbit skeletal muscle. The experimentally-determined octanol/water partition coefficient (LogP) of echinochrome was +3.11, and the distribution coefficient (LogD) was +2.58 at pH 6.0 and -0.15 at pH 8.0. Echinochrome displayed high scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals with a stoichiometry of about 1:7. Echinochrome was more effective in inhibiting the phosphatidyl choline liposome peroxidation induced by Fe2+/ascorbate than that induced by hemin. The iron chelating ability of echinochrome was estimated spectrophotometrically. In isolated SR, echinochrome protected the ATP-dependent Ca2+-pump system from damage by Fe2+/ascorbate. It was concluded that iron chelation predominates in the overall antioxidant potential of echinochrome. Topics: Animals; Biphenyl Compounds; Calcium; Free Radical Scavengers; Hydrazines; Iron Chelating Agents; Lipid Peroxidation; Liposomes; Naphthoquinones; Octanols; Oxidation-Reduction; Picrates; Rabbits; Sarcoplasmic Reticulum; Solvents; Water	2005

Article

Year

Echinamines A and B, first aminated hydroxynaphthazarins from the sea urchin Scaphechinus mirabilis.

Journal of natural products, 2005, Volume: 68, Issue:9

Two new spinochromes, echinamines A (1) and B (2), were isolated from the sea urchin Scaphechinus mirabilis. Compounds 1 and 2 represent the first examples of natural polyhydroxynaphthazarins with a primary amine group. The structures of 1 and 2 were established by analysis of spectroscopic data and synthesis of their dimethyl ethers.

Topics: Animals; Biphenyl Compounds; Japan; Molecular Structure; Naphthoquinones; Nuclear Magnetic Resonance, Biomolecular; Picrates; Sea Urchins

2005

Echinochrome, a naturally occurring iron chelator and free radical scavenger in artificial and natural membrane systems.

Life sciences, 2005, Jan-07, Volume: 76, Issue:8

Echinochrome, or 6-ethyl-2,3,5,7,8-pentahydroxy-1,4-naphthoquinone, possesses cardioprotective activity, and diminishes the myocardial ischemia/reperfusion injury that is known to be accompanied by free-radical oxidative damage and calcium overload. In this study, we investigated the lipophilicity of echinochrome, its ability to inhibit free-radical oxidation both in the bulk organic phase and in an artificial membrane system (liposomes), and to prevent the ferrous/ascorbate-induced leakage of calcium from the isolated sarcoplasmic reticulum (SR) of rabbit skeletal muscle. The experimentally-determined octanol/water partition coefficient (LogP) of echinochrome was +3.11, and the distribution coefficient (LogD) was +2.58 at pH 6.0 and -0.15 at pH 8.0. Echinochrome displayed high scavenging activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals with a stoichiometry of about 1:7. Echinochrome was more effective in inhibiting the phosphatidyl choline liposome peroxidation induced by Fe2+/ascorbate than that induced by hemin. The iron chelating ability of echinochrome was estimated spectrophotometrically. In isolated SR, echinochrome protected the ATP-dependent Ca2+-pump system from damage by Fe2+/ascorbate. It was concluded that iron chelation predominates in the overall antioxidant potential of echinochrome.

Topics: Animals; Biphenyl Compounds; Calcium; Free Radical Scavengers; Hydrazines; Iron Chelating Agents; Lipid Peroxidation; Liposomes; Naphthoquinones; Octanols; Oxidation-Reduction; Picrates; Rabbits; Sarcoplasmic Reticulum; Solvents; Water

2005