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Search for "antioxidant" in Full Text gives 115 result(s) in Beilstein Journal of Organic Chemistry.

Synthesis and anticancer activity of bis(2-arylimidazo[1,2-a]pyridin-3-yl) selenides and diselenides: the copper-catalyzed tandem C–H selenation of 2-arylimidazo[1,2-a]pyridine with selenium

  • Mio Matsumura,
  • Tsutomu Takahashi,
  • Hikari Yamauchi,
  • Shunsuke Sakuma,
  • Yukako Hayashi,
  • Tadashi Hyodo,
  • Tohru Obata,
  • Kentaro Yamaguchi,
  • Yasuyuki Fujiwara and
  • Shuji Yasuike

Beilstein J. Org. Chem. 2020, 16, 1075–1083, doi:10.3762/bjoc.16.94

Graphical Abstract
  • variety of methods [14][15], and many of the targets exhibited biological activity (Figure 1). For example, bis(2-pyridyl) diselenide I has the potential to mitigate oxidative stress and inhibits the AChE activity [16], bis(quinolin-8-yl) diselenide (II) exhibited antioxidant activity in a skin cell model
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Published 20 May 2020

Reaction of indoles with aromatic fluoromethyl ketones: an efficient synthesis of trifluoromethyl(indolyl)phenylmethanols using K2CO3/n-Bu4PBr in water

  • Thanigaimalai Pillaiyar,
  • Masoud Sedaghati and
  • Gregor Schnakenburg

Beilstein J. Org. Chem. 2020, 16, 778–790, doi:10.3762/bjoc.16.71

Graphical Abstract
  • cruciferous vegetables [15], has a wide range of biomedical applications as an anticancer [16], antioxidant, and antiatherogenic agent [17]. Organofluorine compounds have attracted much attention due to their potential biological applications in medicinal and agricultural sciences. Introducing fluoro groups
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Published 20 Apr 2020

The interaction between cucurbit[8]uril and baicalein and the effect on baicalein properties

  • Xiaodong Zhang,
  • Jun Xie,
  • Zhiling Xu,
  • Zhu Tao and
  • Qianjun Zhang

Beilstein J. Org. Chem. 2020, 16, 71–77, doi:10.3762/bjoc.16.9

Graphical Abstract
  • solution using 1H NMR, UV–vis and IR spectroscopy, and DTA. The properties of the BALE–Q[8] inclusion complex, such as stability, solubility, in vitro antioxidant activity and release performance were studied by means of UV–vis spectroscopy. Results and Discussion Host–guest interactions Q[8] and BALE in
  • Supporting Information File 1). If the BALE–Q[8] complex significantly reduces its antioxidant activity, this will affect the medicinal value of BALE. Figure 9 shows that Q[8] has no significant influence on the antioxidant activity of BALE. At 0.0005–0.004 mmol·L−1, BALE exhibited a linear increasing
  • 3.4 × 105 L·mol−1 (neutral water). The solubility of BALE increased 4.67-fold in the phase-solubility experiment when the concentration of Q[8] was 1 × 10−4 mol·L−1. A study of the UV–vis absorption spectra with time showed that Q[8] significantly increased the stability of BALE. The antioxidant
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Published 10 Jan 2020

Construction of trisubstituted chromone skeletons carrying electron-withdrawing groups via PhIO-mediated dehydrogenation and its application to the synthesis of frutinone A

  • Qiao Li,
  • Chen Zhuang,
  • Donghua Wang,
  • Wei Zhang,
  • Rongxuan Jia,
  • Fengxia Sun,
  • Yilin Zhang and
  • Yunfei Du

Beilstein J. Org. Chem. 2019, 15, 2958–2965, doi:10.3762/bjoc.15.291

Graphical Abstract
  • antibacterical [4], antifungal [5][6], anticancer [7], antioxidant [8], anti-HIV [9], antiulcer, immunostimulator [10], anti-inflammatory [11], as well as biocidal [12], wound-healing [13], and immune-stimulatory activities [14]. For instance, flavoxate [15][16] is a chromone derivative that was employed as an
  • of the obtained chromone derivatives was their conversion to chromone-derived natural products. Frutinone A, isolated from the leaves and root bark of Polygala fruticosa, shows various biological activities, including antibacterial, antioxidant, and potent cytochrome P450 1A2 inhibition (CYP1A2, IC50
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Published 12 Dec 2019

In water multicomponent synthesis of low-molecular-mass 4,7-dihydrotetrazolo[1,5-a]pyrimidines

  • Irina G. Tkachenko,
  • Sergey A. Komykhov,
  • Vladimir I. Musatov,
  • Svitlana V. Shishkina,
  • Viktoriya V. Dyakonenko,
  • Vladimir N. Shvets,
  • Mikhail V. Diachkov,
  • Valentyn A. Chebanov and
  • Sergey M. Desenko

Beilstein J. Org. Chem. 2019, 15, 2390–2397, doi:10.3762/bjoc.15.231

Graphical Abstract
  • -dihydrotetrazolo[1,5-a]pyrimidine derivatives. Under similar conditions using 4,4,4-trifluoroacetoacetic ester 5-hydroxy-4,5,6,7-tetrahydrotetrazolo[1,5-a]pyrimidines are obtained. The analogous reaction with acetylacetone requires scandium(III) triflate as catalyst. The antioxidant activity of selected compounds
  • was assayed with 1,1-diphenyl-2-picrylhydrazyl. Keywords: 5-aminotetrazole; antioxidant activity; 1,3-dicarbonyl compounds; multicomponent synthesis; tetrazolo[1,5-a]pyrimidines; Introduction Tetrazolo[1,5-a]pyrimidines and their partially hydrogenated derivatives are known for their interesting
  • biological properties. They have been reported to have anticancer [1], antimicrobial [2][3] and antioxidant [3] activities and to act as inhibitors of hepatitis B virus [4]. The dihydro derivatives of tetrazolo[1,5-a]pyrimidines belong to a bit special kind of dihydropyrimidines due to the strong electron
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Published 08 Oct 2019

Archangelolide: A sesquiterpene lactone with immunobiological potential from Laserpitium archangelica

  • Silvie Rimpelová,
  • Michal Jurášek,
  • Lucie Peterková,
  • Jiří Bejček,
  • Vojtěch Spiwok,
  • Miloš Majdl,
  • Michal Jirásko,
  • Miloš Buděšínský,
  • Juraj Harmatha,
  • Eva Kmoníčková,
  • Pavel Drašar and
  • Tomáš Ruml

Beilstein J. Org. Chem. 2019, 15, 1933–1944, doi:10.3762/bjoc.15.189

Graphical Abstract
  • , antioxidant, antiprotozoal, antiviral and immunobiological activities (reviewed in [1][2]). Two SLs remarkable for their immunobiological potential are archangelolide (1) and trilobolide (2), depicted in Figure 1. Compound 2 exhibits strong induction of nitric oxide (NO) in eukaryotic cells, which in turn
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Published 13 Aug 2019

Steroid diversification by multicomponent reactions

  • Leslie Reguera,
  • Cecilia I. Attorresi,
  • Javier A. Ramírez and
  • Daniel G. Rivera

Beilstein J. Org. Chem. 2019, 15, 1236–1256, doi:10.3762/bjoc.15.121

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  • cerebral injection of lipopolysaccharide endotoxin, with some compounds showing antioxidant and antineuroinflammatory activities. The same group employed this 4CR with cholestan-3-one for the construction of 2-amino-3-cyanodihydropyridine scaffold fused to ring A of the cholestane system [45]. Also
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Published 06 Jun 2019

Synthesis of polydicyclopentadiene using the Cp2TiCl2/Et2AlCl catalytic system and thin-layer oxidation of the polymer in air

  • Zhargolma B. Bazarova,
  • Ludmila S. Soroka,
  • Alex A. Lyapkov,
  • Мekhman S. Yusubov and
  • Francis Verpoort

Beilstein J. Org. Chem. 2019, 15, 733–745, doi:10.3762/bjoc.15.69

Graphical Abstract
  • through the layers. Consequently, this leads to the transition of the oxidation from a kinetic mode into a diffusive mode. Such structural changes do not occur in a polymer that was stabilized by adding an antioxidant. Keywords: bis(cyclopentadienyl)titanium dichloride; cationic polymerization; oxidation
  • occur in the polymer which was stabilized by adding an antioxidant (Agidole-1 in the amount of 0.2% by mass). The infrared spectrum of the thin layer of the stabilized polymer (Figure 17a) does not change and no consumption of double bonds in the polymer can be detected (Figure 17b). Conclusion This
  • mode into a diffusion one. These structural changes do not occur in a polymer stabilized by adding an antioxidant in the studied period of time. Experimental Dehydrated toluene, prepared according to a well-known procedure, was used as a solvent [30]. Polymerization of DCPD in toluene was carried out
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Published 20 Mar 2019

Synthesis of the aglycon of scorzodihydrostilbenes B and D

  • Katja Weimann and
  • Manfred Braun

Beilstein J. Org. Chem. 2019, 15, 610–616, doi:10.3762/bjoc.15.56

Graphical Abstract
  • highly oxygenated aryl rings. Scorzodihydrostilbene E (5) features a dimeric skeleton that originates from an oxidative coupling of compound 1. The natural products exhibited antioxidative activity that was partly stronger than that of the well-known naturally occurring antioxidant resveratrol [5]. In
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Published 06 Mar 2019

Synthesis of a tyrosinase inhibitor by consecutive ethenolysis and cross-metathesis of crude cashew nutshell liquid

  • Jacqueline Pollini,
  • Valentina Bragoni and
  • Lukas J. Gooßen

Beilstein J. Org. Chem. 2018, 14, 2737–2744, doi:10.3762/bjoc.14.252

Graphical Abstract
  • display a broad range of biological activities such as antimicrobial [23], antioxidant [24], molluscicidal [25] and antiplaque [26]. Ginkgolic acids, structurally closely related analogues of anacardic acid, have been reported to exhibit tyrosinase inhibitory activity [27]. We herein report a concise
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Published 31 Oct 2018

Assembly of fully substituted triazolochromenes via a novel multicomponent reaction or mechanochemical synthesis

  • Robby Vroemans,
  • Yenthel Verhaegen,
  • My Tran Thi Dieu and
  • Wim Dehaen

Beilstein J. Org. Chem. 2018, 14, 2689–2697, doi:10.3762/bjoc.14.246

Graphical Abstract
  • equivalent nitroalkene, 1.2 equivalents of salicylaldehyde and 0.1 equivalents of DABCO as catalyst in the first step at 40 °C, and 2 equivalents of benzyl azide, 2 equivalents of acetic acid, 0.3 equivalents of BHT as antioxidant, 4 Å MS and DMF under argon atmosphere at 120 °C in the second step. Crude NMR
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Published 22 Oct 2018

Targeting the Pseudomonas quinolone signal quorum sensing system for the discovery of novel anti-infective pathoblockers

  • Christian Schütz and
  • Martin Empting

Beilstein J. Org. Chem. 2018, 14, 2627–2645, doi:10.3762/bjoc.14.241

Graphical Abstract
  • effects are mediated either through direct PqsR-dependent action or by PqsR-independent mechanisms, which are most likely due to the iron-chelating as well as antioxidant properties of PQS [33]. Furthermore, it has been unravelled that the thioesterase PqsE, whose biosynthetic function is dispensable due
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Published 15 Oct 2018

One hundred years of benzotropone chemistry

  • Arif Dastan,
  • Haydar Kilic and
  • Nurullah Saracoglu

Beilstein J. Org. Chem. 2018, 14, 1120–1180, doi:10.3762/bjoc.14.98

Graphical Abstract
  • ][36]. Purpurogallin (8), which is biogenetically produced by oxidation of pyrogallol, and its analogues (like 9) are natural pigments (Figure 1) [37][38][39][40][41][42][43][44]. Theaflavin (10) and its derivatives, named theaflavins, are antioxidant benzotropones that are formed by the enzymatic
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Published 23 May 2018

An overview of recent advances in duplex DNA recognition by small molecules

  • Sayantan Bhaduri,
  • Nihar Ranjan and
  • Dev P. Arya

Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93

Graphical Abstract
  • , dihydrofuranocoumarins are another class of coumarins possessing anticancer activities. Recently, Ahmadi et al. identified several dihydrofuranocoumarins, especially grandivittin (GRA), from Ferulago macrocarpa (Fenzl) Boiss., and their mechanism of minor groove DNA binding and antibacterial, cytotoxic and antioxidant
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Published 16 May 2018

Continuous-flow retro-Diels–Alder reaction: an efficient method for the preparation of pyrimidinone derivatives

  • Imane Nekkaa,
  • Márta Palkó,
  • István M. Mándity and
  • Ferenc Fülöp

Beilstein J. Org. Chem. 2018, 14, 318–324, doi:10.3762/bjoc.14.20

Graphical Abstract
  • antibiotics [41]. Our aim in the present study was to synthesize functionalized pyrimidinone systems through rDA reactions. Many of these products are of high importance in drug design due to their diverse biological properties including antimicrobial, antiviral, antioxidant and antitumor activities. In
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Published 01 Feb 2018

5-Aminopyrazole as precursor in design and synthesis of fused pyrazoloazines

  • Ranjana Aggarwal and
  • Suresh Kumar

Beilstein J. Org. Chem. 2018, 14, 203–242, doi:10.3762/bjoc.14.15

Graphical Abstract
  • pharmacological activities such as: anticancer [1][2], anti-inflammatory [3][4], antioxidant [5], antibacterial [6][7][8], analgesic [9], antiviral [10][11], antimicrobial [12][13], antifungal [6], antiglycemic [14], antiamoebic [15] and antidepressive [16][17]. Considering the immense biological properties
  • ], protein kinase inhibitors [32], antiallergic [33], antioxidant [34] and as fungicide [35]. Also, the pyrazolo[3,4-b]pyridine ring system is a key structure in drug discovery and has become the main component in many medicinally important compounds. The large number of synthetic routes to pyrazolo[3,4-b
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Published 25 Jan 2018

Synthesis of naturally-derived macromolecules through simplified electrochemically mediated ATRP

  • Paweł Chmielarz,
  • Tomasz Pacześniak,
  • Katarzyna Rydel-Ciszek,
  • Izabela Zaborniak,
  • Paulina Biedka and
  • Andrzej Sobkowiak

Beilstein J. Org. Chem. 2017, 13, 2466–2472, doi:10.3762/bjoc.13.243

Graphical Abstract
  • solution to receive functionalised polymers. It is a naturally occurring flavonoid, which is abundantly found in citrus fruits, herbs, vegetables, seeds, tea, nuts, and red wine [24][25][26]. It is considered to be a strong antioxidant due to its ability to scavenge free radicals and bind transition metal
  • ions [27]. Quercetin inhibits xanthine oxidase [27][28][29], inhibits lipid peroxidation in vitro [27][28][30], and scavenges oxygen radicals [27][28][31][32][33]. There is a tremendous importance of this antioxidant in the prevention of a range of cardiovascular diseases [27][34][35], cancer [26][27
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Published 20 Nov 2017

Synthesis, effect of substituents on the regiochemistry and equilibrium studies of tetrazolo[1,5-a]pyrimidine/2-azidopyrimidines

  • Elisandra Scapin,
  • Paulo R. S. Salbego,
  • Caroline R. Bender,
  • Alexandre R. Meyer,
  • Anderson B. Pagliari,
  • Tainára Orlando,
  • Geórgia C. Zimmer,
  • Clarissa P. Frizzo,
  • Helio G. Bonacorso,
  • Nilo Zanatta and
  • Marcos A. P. Martins

Beilstein J. Org. Chem. 2017, 13, 2396–2407, doi:10.3762/bjoc.13.237

Graphical Abstract
  • the pharmaceutical field due to their significant potential to exhibit antitumor, antimicrobial, and antioxidant activities [1][2]. In addition to acting as a stimulant of the central nervous system [3], this class of substances plays an important role in drugs that are used to treat obesity, diabetes
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Published 10 Nov 2017

Curcuminoid–BF2 complexes: Synthesis, fluorescence and optimization of BF2 group cleavage

  • Henning Weiss,
  • Jeannine Reichel,
  • Helmar Görls,
  • Kilian Rolf Anton Schneider,
  • Mathias Micheel,
  • Michael Pröhl,
  • Michael Gottschaldt,
  • Benjamin Dietzek and
  • Wolfgang Weigand

Beilstein J. Org. Chem. 2017, 13, 2264–2272, doi:10.3762/bjoc.13.223

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  • curcuma longa, and its analogues, the curcuminoids, have attracted much attention regarding their biological activities [1]. These include antioxidant [2] and radical scavenging [3], antitumor [4] and anti-inflammatory [5] activities, as well as HIV inhibition [6]. Despite showing activity against several
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Published 26 Oct 2017

Solid-state studies and antioxidant properties of the γ-cyclodextrin·fisetin inclusion compound

  • Joana M. Pais,
  • Maria João Barroca,
  • Maria Paula M. Marques,
  • Filipe A. Almeida Paz and
  • Susana S. Braga

Beilstein J. Org. Chem. 2017, 13, 2138–2145, doi:10.3762/bjoc.13.212

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  • ‘‘Molecular Physical-Chemistry – QFM-UC”, University of Coimbra, 3004-535 Coimbra, Portugal Department of Life Sciences, University of Coimbra, 3000-456 Coimbra, Portugal 10.3762/bjoc.13.212 Abstract Fisetin is a natural antioxidant with a wide range of nutraceutical properties, including antidiabetic
  • using elemental analysis, powder X-ray diffraction (PXRD), Raman, infrared and 13C{1H} CP-MAS NMR spectroscopies, and thermal analysis (TGA) to verify fisetin inclusion and to present a hypothetical structural arrangement for the host–guest units. The antioxidant activity of the γ-CD·fisetin inclusion
  • compound is evaluated by the DPPH assay. Keywords: antioxidant activity; co-lyophilization; fisetin; gamma-cyclodextrin; molecular encapsulation; solid-state analysis; Introduction Flavonoids, natural compounds with numerous beneficial actions on human health, including antioxidant [1], anti-inflammatory
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Published 13 Oct 2017

Selective enzymatic esterification of lignin model compounds in the ball mill

  • Ulla Weißbach,
  • Saumya Dabral,
  • Laure Konnert,
  • Carsten Bolm and
  • José G. Hernández

Beilstein J. Org. Chem. 2017, 13, 1788–1795, doi:10.3762/bjoc.13.173

Graphical Abstract
  • antioxidant, antibacterial and sun protection properties [17][23][24]. Motivated by the aforementioned scenario and in line with our research interest on studying the compatibility of biocatalysts and mechanochemical milling, we decided to investigate the enzymatic esterification of lignin model compounds in
  • addressing the centrally-located primary aliphatic hydroxyl content of lignins is still highly possible. This strategy is expected to allow the preservation of the phenolic and benzylic alcohol contents in modified lignins, in order to keep the antibacterial and antioxidant activities of this biopolymer
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Published 25 Aug 2017

Use of costic acid, a natural extract from Dittrichia viscosa, for the control of Varroa destructor, a parasite of the European honey bee

  • Kalliopi Sofou,
  • Demosthenis Isaakidis,
  • Apostolos Spyros,
  • Anita Büttner,
  • Athanassios Giannis and
  • Haralambos E. Katerinopoulos

Beilstein J. Org. Chem. 2017, 13, 952–959, doi:10.3762/bjoc.13.96

Graphical Abstract
  • essential oil were found active against Staphylococcus epidermidis, Streptococcus foecalis and Proteus vulgaris [36]. The methanol extract of the aerial parts of the plant showed antioxidant activity in a study on lipid peroxidation of rat liver microsomes [30]. n-Hexane extracts from air dried D. viscosa
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Published 18 May 2017

Ultrasound-promoted organocatalytic enamine–azide [3 + 2] cycloaddition reactions for the synthesis of ((arylselanyl)phenyl-1H-1,2,3-triazol-4-yl)ketones

  • Gabriel P. Costa,
  • Natália Seus,
  • Juliano A. Roehrs,
  • Raquel G. Jacob,
  • Ricardo F. Schumacher,
  • Thiago Barcellos,
  • Rafael Luque and
  • Diego Alves

Beilstein J. Org. Chem. 2017, 13, 694–702, doi:10.3762/bjoc.13.68

Graphical Abstract
  • -(phenylselanylmethyl)-1,2,3-triazole A (Se-TZ) demonstrated an antidepressant-like effect (Figure 1) [60]. In another example, 5-phenyl-1-(2-(phenylselanyl)phenyl)-1H-1,2,3-triazole-4-carbonitrile B (Se-TZCN) was reported to exhibit antioxidant activities in different in vitro assays (Figure 1) [36]. Selenanyl-quinone
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Published 11 Apr 2017

Biomimetic synthesis and HPLC–ECD analysis of the isomers of dracocephins A and B

  • Viktor Ilkei,
  • András Spaits,
  • Anita Prechl,
  • Áron Szigetvári,
  • Zoltán Béni,
  • Miklós Dékány,
  • Csaba Szántay Jr,
  • Judit Müller,
  • Árpád Könczöl,
  • Ádám Szappanos,
  • Attila Mándi,
  • Sándor Antus,
  • Ana Martins,
  • Attila Hunyadi,
  • György Tibor Balogh,
  • György Kalaus (†),
  • Hedvig Bölcskei,
  • László Hazai and
  • Tibor Kurtán

Beilstein J. Org. Chem. 2016, 12, 2523–2534, doi:10.3762/bjoc.12.247

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  • increase P-gp inhibitory activity [18]. Based on the unaltered accumulation of rhodamine 123, a P-gp substrate fluorescent dye, in the P-gp transfected L5178MDR cells, we observed that none of the synthesized compounds inhibits this transporter. The antioxidant activity of dracocephins A and B was also
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Published 24 Nov 2016

Tunable microwave-assisted method for the solvent-free and catalyst-free peracetylation of natural products

  • Manuela Oliverio,
  • Paola Costanzo,
  • Monica Nardi,
  • Carla Calandruccio,
  • Raffaele Salerno and
  • Antonio Procopio

Beilstein J. Org. Chem. 2016, 12, 2222–2233, doi:10.3762/bjoc.12.214

Graphical Abstract
  • ester (8), uridine (12) and methyl-α-D-glucopyranoside (11)) and natural antioxidant compounds in their simple (hydroxytyrosol (4), homovanillic alcohol (5), quercetin (13)) or glycosylated forms (oleuropein (14), rutin (17), alpha-hederin (16)). Because of their heterogeneity in terms of
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Published 20 Oct 2016
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