Antioxidant galloylated flavonol glycosides from <b> <i>Calliandra haematocephala</i> </b>

Moharram, Fatma A.; Marzouk, Mohamed; Ibrahim, Magda T.; Mabry, Tom J.

doi:10.1080/14786410500378494

Cited by 49 publications

(30 citation statements)

References 21 publications

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“…again a large π-electron conjugation system, which extends over rings A and B through an α,β-unsaturated ketone group in ring C. The drop of antioxidant capacity of 9 relative to that of 7 or 8 could be attributed to its lacking 3'-OH and consequently the 3',4'-ortho-dihydroxy substituents. This function was reported to play an essential role in the stabilization of the aryloxy radical after H-donation by the +R-effect of hydroxy groups at the 3-, 3'-, and 4'-positions (Moharram et al, 2006). However, the mixture of 11 and 12 showed highest activity among all fl avonoids because of the extra galloyl moiety with three orthohydroxy groups.…”

Section: Antitumour Activitymentioning

confidence: 99%

“…According to α/β down/upfi eld 13 C substituent additive rules of glycosidation (Agrawal and Bansal, 1989) and esterifi cation (Okuda et al, 1989), δ values of sugar signals, specially those of C-2", C-3", and C-6", were in complete accordance with a 3-Oglycoside and 2",3",6"-galloylation. The full assignment of all remaining 1 H and 13 C resonances was confi rmed by comparison with previously published data (Marzouk et al, 2007;Agrawal and Bansal, 1989;Moharram et al, 2006) …”

Section: Chemistrymentioning

confidence: 99%

“…In the aliphatic region a β-anomeric proton doublet was located at δ H 5.95 ppm (J = 8 Hz), whose downfi eld position (Δ + 0.5 ppm) is characteristic for acylation of the vicinal OH-2". Intrinsic downfi eld location (Δ + 1.5 ppm) of H-2" and H-3" at δ H 5.22 ppm (dd) and 5.42 ppm (t-like) was indicative of the galloylation of OH-2" and OH-3" (Moharram et al, 2006). The third galloyl ester was proven to be at OH-6" due to the characteristic downfi eld shift of its own diastereomeric CH 2 -6" protons at δ H 4.34 ppm and 4.27 ppm (Δ + 0.5 ppm).…”

Section: Chemistrymentioning

confidence: 99%

“…The 13 C NMR spectrum showed 13 signals typical for a kaempferol aglycone including fi ve key signals at δ C 178.25 ppm (C-4), 133.70 ppm (C-3), 131.13 ppm (C-2'/6'), and 115.87 ppm (C-3'/5') (Agrawal and Bansal, 1989). Likewise, the characteristic fi ve 13 C resonances of the galloyl moiety were repeated three times at about 165.0 ppm (3 x C-7), 145.5 ppm (3 x C-3/5), 138.5 ppm (3 x C-4), 119.0 ppm (3 x C-1), and 109.0 ppm (3 x C-2/6) (Gupta et al, 1982;Moharram et al, 2006). According to α/β down/upfi eld 13 C substituent additive rules of glycosidation (Agrawal and Bansal, 1989) and esterifi cation (Okuda et al, 1989), δ values of sugar signals, specially those of C-2", C-3", and C-6", were in complete accordance with a 3-Oglycoside and 2",3",6"-galloylation.…”

Section: Chemistrymentioning

confidence: 99%

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Spectroscopic Identifi cation of New Ellagitannins and a Trigalloylglucosylkaempferol from an Extract of Euphorbia cotinifolia L. with Antitumour and Antioxidant Activity

Marzouk

Moharram

Gamal‐Eldeen

et al. 2012

Zeitschrift Für Naturforschung C

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From an extract of leaves and small branches of Euphorbia cotinifolia L., 17 polyphenols were isolated including two new ellagitannins and a trigalloyl-glucosylkaempferol. Based on extensive spectral data (UV, ESI-MS, 1 H NMR, DEPT and 1D/2D NMR) and chemical studies, their structures were characterized as 1-O-galloyl-3,6-hexahydroxydiphenoyl-D-B 1,4 -glucopyranose (5), 1-O-galloyl-3,6-valoneoyl-D-B 1,4 -glucopyranose (6), and kaempferol 3-O-(2",3",6"-tri-O-galloyl)-β-D-glucopyranoside (13). Biological evaluation indicated that the 80% aqueous methanol extract (AME), chloroform extract (CE), and some pure compounds have potent scavenging activity in the DPPH assay with SC 50 values lower than that of ascorbic acid, especially 5, 7 -9, and a mixture of hyperin 6"-gallate (11) and isoquercitrin 6"-gallate (12). Moreover, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) cell viability assay, 6 and 8 exhibited the highest inhibition of human hepatocellular carcinoma cells (Hep-G2), while AME, CE, 5, 7, 9, and the mixture of 11 and 12 were found to be moderate growth inhibitors according to their IC 50 values. In addition, AME, 5, and 8 exhibited signifi cant antiproliferative activity against colon carcinoma cells (HCT-116); however, CE and the other examined compounds displayed moderate to low antitumour activity against HCT-116 cells.

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Section: Antitumour Activitymentioning

confidence: 99%

Section: Chemistrymentioning

confidence: 99%

Section: Chemistrymentioning

confidence: 99%

Section: Chemistrymentioning

confidence: 99%

See 2 more Smart Citations

Spectroscopic Identifi cation of New Ellagitannins and a Trigalloylglucosylkaempferol from an Extract of Euphorbia cotinifolia L. with Antitumour and Antioxidant Activity

Marzouk

Moharram

Gamal‐Eldeen

et al. 2012

Zeitschrift Für Naturforschung C

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“…38 It also has other activities such as antidiarrhoeal, lethal effect towards brine shrimp Artemia salina, angiotensin converting enzyme (ACE) inhibitory activity synergistic, aldose reductase inhibitory, antimalarial, antioxidant (DPPH and ABTS), analgesic, anti-inflammatory in experimental colitis model and inhibitory the function of P-glycoprotein and MRP1. [30][31][32][33][34]39 In addition, quercitrin decrease the ethanol/HCl-induced gastric ulcer, prevents the depletion of gastric glutathione (GSH) contente, reduce the myeloperoxidase (MPO) activity and also inhibits the H + , K + , -ATPase activity. 40 The kaempferol-3-O-α-L-rhamnoside (afzelin, 3), was isolated and identified in the species B. microstachya and B. megalandra.…”

mentioning

confidence: 99%

PHENOLIC DERIVATIVES AND ANTIOXIDANT ACTIVITY OF POLAR EXTRACTS FROM Bauhinia pulchella

et al. 2018

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publicado na web em 18/01/2018 A tea made with the leaves or stem bark of Bauhinia pulchella Benth (Fabaceae) is used in the treatment of diabetes. Ethanol (EEF) and aqueous (EAF) extracts were obtained from the leaves and the antioxidant and citotoxic activities were tested, as well as quantify the content of flavonoids and phenolic compounds (TPC). EEF and EAF showed similar profiles by HPLC, with the presence of three compounds. Column chromatography reverse phase (C18) and Sephadex LH-20, followed by semi preparative HPLC-C18 of EAF resulted in three flavonoids. Their structures were identified by 1 H and 13 C NMR as myricitrin (1), quercitrin (2) and afzelin (3). In assay of determination of reactive substances to thiobarbituric acid (TBARS), with DPPH, ABTS and nitric oxide (NO•) free radicals, EAF showed antioxidant potential higher than the EEF. This is the first report of the occurrence of the flavonoids 1-3, in the species B. pulchella. EEF and EAF were inactive in the cytotoxicity assays. In short, the polar extracts from the leaves of B. pulchella proved to be promising sources of biomolecules phenolic, with antioxidant potential, which may, in the future, be used as chemical markers for species and validation of therapeutic use.

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Phenolic Derivatives from Ruprechtia polystachya and Their Inhibitory Activities on the Glucose‐6‐phosphatase System

Abreu

Temraz

Malafronte

et al. 2011

Chemistry & Biodiversity

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Two new compounds, 5-methyl-2-(2-methylbutanoyl)phloroglucinol 1-O-(6-O-β-D-apiofuranosyl)-β-D-glucopyranoside (1) and trans-2,3-dihydrokaempferol 3-O-(4-O-sulfo)-α-L-arabinopyranoside (2), together with 14 known flavonoids, trans-dihydrokaempferol 3-O-α-L-arabinopyranoside (3), trans-taxifolin 3-O-α-L-arabinofuranoside (4), quercetin 3-O-α-L-rhamnopyranoside (5), quercetin 3'-O-α-L-arabinofuranoside (6), catechin 3-O-α-L-rhamnopyranoside (7), trans-taxifolin 3-O-α-L-arabinopyranoside (8), cis-dihydrokaempferol 3-O-α-L-arabinopyranoside (9), catechin (10), myricetin 3-O-α-L-rhamnopyranoside (11), quercetin 3-O-α-L-arabinopyranoside (12), quercetin 3-O-α-L-arabinofuranoside (13), quercetin 3-O-(3″-galloyl)-α-L-rhamnopyranoside (14), quercetin 3-O-(2″-galloyl)-α-L-rhamnopyranoside (15), and epicatechin 3-O-gallate (16), were isolated from the leaves of Ruprechtia polystachya Griseb. (Polygonaceae). Their structures were established on the basis of extensive 1D- and 2D-NMR experiments as well as MS analyses. All compounds, except 1, showed inhibition of the enzyme glucose-6-phosphatase in intact microsomes.

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Antioxidant galloylated flavonol glycosides from Calliandra haematocephala

Cited by 49 publications

References 21 publications

Spectroscopic Identifi cation of New Ellagitannins and a Trigalloylglucosylkaempferol from an Extract of Euphorbia cotinifolia L. with Antitumour and Antioxidant Activity

Spectroscopic Identifi cation of New Ellagitannins and a Trigalloylglucosylkaempferol from an Extract of Euphorbia cotinifolia L. with Antitumour and Antioxidant Activity

PHENOLIC DERIVATIVES AND ANTIOXIDANT ACTIVITY OF POLAR EXTRACTS FROM Bauhinia pulchella

Phenolic Derivatives from Ruprechtia polystachya and Their Inhibitory Activities on the Glucose‐6‐phosphatase System

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