Total synthesis of demethylwedelolactone and wedelolactone by Cu-mediated/Pd(0)-catalysis and oxidative-cyclization

Chang, Chia‐Fu; Yang, Lingyi; Chang, Shiao-Wei; Fang, Yuting; Lee, Yean‐Jang

doi:10.1016/j.tet.2008.02.031

Cited by 32 publications

(20 citation statements)

References 22 publications

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“…The herb, W. chinensis , was purchased from a reputable folk medicine store in Taiwan and identified by associate professor Ko-Kaung Liao, who majors in Biology and is familiar with medicinal plants. Wedelolactone, 7-methoxy-5, 11, 12-trihydroxy-coumestan, was synthesized from commercially available phloroglucinol [ 21 ]. All chemicals were analytical grade purchased from Sigma-Aldrich (USA) and Merck (Germany).…”

Section: Methodsmentioning

confidence: 99%

Ethyl acetate extract of Wedelia chinensis inhibits tert-butyl hydroperoxide-induced damage in PC12 cells and D-galactose-induced neuronal cell loss in mice

Lin

Wang

et al. 2014

BMC Complement Altern Med

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BackgroundWedelia chinensis is traditionally used as a hepatoprotective herb in Taiwan. The aim of this study was to evaluate the neuroprotective potential of W. chinensis.MethodsAn ethyl acetate extract of W. chinensis (EAW) was prepared and analyzed by HPLC. The neuroprotective potential of EAW was assessed by tert-butylhydroperoxide (t-BHP)-induced damage in PC12 cells and D-galactose-induced damage in mouse cortex.ResultsEAW exhibited potent radical scavenging property and highly contained luteolin and wedelolactone. EAW decreased t-BHP-induced reactive oxygen species (ROS) accumulation, cytotoxicity and apoptosis in PC12 cells. EAW and its major constituents blocked t-BHP-induced cytochrome C release and Bcl-2 family protein ratio change. EAW and its major constituents increased the endogenous antioxidant capacity evaluated by the binding activity assay of nuclear factor E2-related factor 2 (Nrf2) to antioxidant response element (ARE) and nuclear translocation of Nrf2 respectively in PC12 cells. Finally, EAW inhibited D-galactose-induced lipid peroxidation, apoptosis and neuron loss in the cerebral cortex of mice.ConclusionThese results demonstrate that W. chinensis has neuroprotective potential through blocking oxidative stress-induced damage and that luteolin and wedelolactone contribute to the protective action.

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Section: Methodsmentioning

confidence: 99%

Ethyl acetate extract of Wedelia chinensis inhibits tert-butyl hydroperoxide-induced damage in PC12 cells and D-galactose-induced neuronal cell loss in mice

Lin

Wang

et al. 2014

BMC Complement Altern Med

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“…A promising approach to construct these structures is the oxidative coupling between the catechols and hydroxycoumarins . This reaction has two advantages over other reactions that use halogen‐, trifluoromethanesulfonate‐ or tributyltin‐substituted aromatic compounds as the starting material. This method allows the direct use of substrates without prefunctionalization and involves the formation of C−C and C−O bonds in a cascade‐type reaction.…”

Section: Figurementioning

confidence: 99%

Efficient Synthesis of Benzofurans via Cross‐Coupling of Catechols with Hydroxycoumarins Using O₂ as an Oxidant Catalyzed by AlPO₄‐Supported Rh Nanoparticle

et al. 2019

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An efficient synthesis of benzofuran derivatives via the cross‐coupling of catechols and hydroxycoumarins in H2O using O2 as an ideal oxidant is reported. The above reaction allows the direct use of substrates without prefunctionalization, involves formation of C−C and C−O bonds in cascade manner, and affords H2O as the sole by‐product. This simple and clean reaction is achieved by the development of an AlPO4‐supported Rh nanoparticle catalyst. The catalyst was applicable to the synthesis of a wide range of benzofurans. We also successfully utilized this catalytic method for total synthesis of flemichapparin C, one of the naturally occurring coumestans exhibiting bioactivity. The combined functions of Rh nanoparticles and AlPO4 play a key role in this reaction where in situ generated o‐benzoquinone by Rh nanoparticles is possibly an intermediate for nucleophilic addition to hydroxycoumarins on AlPO4.

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“…Data pada tabel 2 merupakan hasil rekapitulasi konfirmasi pengukuran NMR hasil percobaan dan hasil referensi. Dari tabel tersebut terlihat spektrum proton dan karbon isolat berada pada daerah geseran kimia (δ) yang relatif sama dengan yang dilaporkan oleh Li et al, (2003) dan Chang et al, (2008). Ini menunjukkan bahwa berdasarkan pengukuran 1 HNMR dan 13 CNMR, isolat hasil percobaan merupakan senyawa wedelolakton (Yuliana, 2013).…”

Section: Hasil Dan Pembahasan Karakterisasi Isolatunclassified

Antioxidant Activity of Wedelolakton from Urang Aring (Eclipta alba (L.) Hassk) Ethyl Acetate Fraction

Yuliana

2017

Jurnal Kimia VALENSI

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Urang aring (Eclipta alba (L.) Hassk secara tradisional telah banyak digunakan sebagai tumbuhan obat. Daun urang-aring banyak digunakan untuk mengobati sesak nafas, sakit kepala, sakit gigi, bronkhitis, gangguan haid, dan sebagai penyubur rambut. Ekstrak dari tumbuhan urang aring dari berbagai jenis pelarut menunjukkan beberapa aktivitas seperti antioksidan dan antibakteri. Dalam penelitian ini telah dikaji uji aktivitas antioksidan dari wedelolakton murni hasil isolasi dari daun urang aring. Proses isolasi dilakukan secara konvensional menggunakan cara maserasi, partisi, dan kromatografi kolom serta dikarakterisasi dengan menggunakan KLT, LCMS dan spektroskopi UV-Vis dan NMR. Hasil percobaan menunjukkan, isolat wedelolakton mempunyai aktivitas antioksidan IC 50 pada konsentrasi (5.6±0.5) ug/mL didampingi dengan asam askorbat sebagai kontrol positif.

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Total synthesis of demethylwedelolactone and wedelolactone by Cu-mediated/Pd(0)-catalysis and oxidative-cyclization

Cited by 32 publications

References 22 publications

Ethyl acetate extract of Wedelia chinensis inhibits tert-butyl hydroperoxide-induced damage in PC12 cells and D-galactose-induced neuronal cell loss in mice

Ethyl acetate extract of Wedelia chinensis inhibits tert-butyl hydroperoxide-induced damage in PC12 cells and D-galactose-induced neuronal cell loss in mice

Efficient Synthesis of Benzofurans via Cross‐Coupling of Catechols with Hydroxycoumarins Using O₂ as an Oxidant Catalyzed by AlPO₄‐Supported Rh Nanoparticle

Antioxidant Activity of Wedelolakton from Urang Aring (Eclipta alba (L.) Hassk) Ethyl Acetate Fraction

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Total synthesis of demethylwedelolactone and wedelolactone by Cu-mediated/Pd(0)-catalysis and oxidative-cyclization

Cited by 32 publications

References 22 publications

Ethyl acetate extract of Wedelia chinensis inhibits tert-butyl hydroperoxide-induced damage in PC12 cells and D-galactose-induced neuronal cell loss in mice

Ethyl acetate extract of Wedelia chinensis inhibits tert-butyl hydroperoxide-induced damage in PC12 cells and D-galactose-induced neuronal cell loss in mice

Efficient Synthesis of Benzofurans via Cross‐Coupling of Catechols with Hydroxycoumarins Using O2 as an Oxidant Catalyzed by AlPO4‐Supported Rh Nanoparticle

Antioxidant Activity of Wedelolakton from Urang Aring (Eclipta alba (L.) Hassk) Ethyl Acetate Fraction

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Efficient Synthesis of Benzofurans via Cross‐Coupling of Catechols with Hydroxycoumarins Using O₂ as an Oxidant Catalyzed by AlPO₄‐Supported Rh Nanoparticle