- A simple and efficient approach for the preparation of dihydroxanthyletin, xanthyletin, decursinol and marmesin
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A simple and efficient approach has been developed for the preparation of coumarin natural products such as dihydroxanthyletin, xanthyletin, decursinol and marmesin starting from commercially available 2,4-dihydroxybenzaldehyde with very good yields. Wittig homologation and Claisen rearrangement are the protocols used to achieve these molecules.
- Kommera, Rajkumar,Bhimapaka, China Raju
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supporting information
p. 3204 - 3211
(2020/08/05)
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- Isolation, structure elucidation, tyrosinase inhibitory, and antioxidant evaluation of the constituents from Angelica dahurica roots
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Two undescribed phenolic compounds, angelicols A (1) and B (2) and one undescribed coumarin rhamnoside, angelicoside A (3), together with 17 known compounds (4–20) were isolated from the roots of Angelica dahurica. Their structures were characterized by physical data analyses such as NMR, HRESIMS, and X-ray diffraction. Compounds 2, 3, 5, 6 and L-ascorbic acid (positive control) exhibited obvious DPPH radical scavenging activities with IC50 values of 0.36?mM, 0.43?mM, 0.39?mM, 0.44?mM, 0.25?mM, respectively. At a concentration of 25?μM, all compounds showed weaker tyrosinase inhibition activities (%inhibition 50 = 44.29 ± 0.06?μM).
- Shu, Penghua,Li, Junping,Fei, Yingying,Zhu, Huiqing,Yu, Mengzhu,Liu, Anqi,Niu, Haoying,Zou, Simin,Wei, Xialan,Ju, Zhiyu,Xu, Zhihong
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p. 456 - 462
(2019/12/24)
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- Synthesis of coumarin derivatives and their cytoprotective effects on t-BHP-induced oxidative damage in HepG2 cells
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Coumarins are ubiquitous in higher plants and exhibit various biological actions. The aim of this study was to investigate the structure-activity relationships of coumarin derivatives on tert-butyl hydroperoxide (t-BHP)-induced oxidative damage in human hepatoma HepG2 cells. A series of coumarin derivatives were prepared and assessed for their cytoprotective effects. Among these, a caffeoyl acid-conjugated dihydropyranocoumarin derivative, caffeoyllomatin, efficiently protected against cell damage elicited by t-BHP. Our findings suggest that caffeoyllomatin appears to be a potent cytoprotective agent.
- Ando, Tomomi,Nagumo, Mina,Ninomiya, Masayuki,Tanaka, Kaori,Linhardt, Robert J.,Koketsu, Mamoru
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supporting information
p. 2422 - 2425
(2018/06/20)
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- Structure-activity relationships for naturally occurring coumarins as β-secretase inhibitor
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The present study was demonstrated to evaluate the effects of naturally occurring coumarins (NOCs) including simple coumarins, furanocoumarins, and pyranocoumarins on the inhibition of β-secretase (BACE1) activity. Of 41 NOCs examined, some furanocoumarins inhibited BACE1 activity, but simple coumarins and pyranocoumarins did not affect. The most potent inhibitor was 5-geranyloxy-8-methoxypsoralen (31), which has an IC50 value of 9.9 μM. Other furanocoumarin derivatives, for example, 8-geranyloxy-5- methoxypsoralen (35), 8-geranyloxypsoralen (24), and bergamottin (18) inhibited BACE1 activity, with the IC50 values 25.0 μM. Analyses of the inhibition mechanism by Dixon plots and Cornish-Bowden plots showed that compounds 18, 31 and 35 were mixed-type inhibitor. The kinetics of inhibition of BACE1 by coumarins 24 was non-competitive inhibitors.
- Marumoto, Shinsuke,Miyazawa, Mitsuo
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supporting information; experimental part
p. 784 - 788
(2012/03/22)
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- Asymmetric synthesis of 2-Substituted dihydrobenzofurans and 3-hydroxydihydrobenzopyrans through the enantioselective epoxidation of O-silyl-protected ortho-allylphenols
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The Shi-type epoxidation of O-tert-butyldiphenylsilyl (TBDPS) protected o-allylphenols serves as an efficient strategy to construct the dihydrobenzofurans and dihydrobenzopyrans in up to 97% ee. This methodology led to the enantioselective synthesis of (+)-marmesin, (-)-(3′R)-decursinol, and (+)-lomatin.
- Jiang, Hang,Sugiyama, Takaya,Hamajima, Akinari,Hamada, Yasumasa
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experimental part
p. 155 - 162
(2011/03/22)
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- Glycosides from the methanol extract of Notopterygium incisum
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Five new (15) and twelve known (617) different types of glycosides together with a known sesquiterpene triol (18) were isolated from the methanol extract of the rhizomes of Notopterygium incisum. The new structures were elucidated by means of spectroscopic and chemical methods to be pregn-5-en-3,20(S)-diol-3-O- bis - D-glucopyranosyl-(l2,16) - D-glucopyranoside (1), oleuropeic aldehyde 8-O - D-glucopyranoside (2), 2(R)-(3,4-dimethoxyphenyl)-propane-1,3-diol-1-O - D-glucopyranoside (3), eudesman-3,4,11-triol-11-O - D-glucopyranoside (4), and marmesin-11-O - D-glucopyranosyl-(16) - D-glucopyranoside (5). The absolute configuration of the aglycone in compound 3 was assigned by application of Klyne's rule. Georg Thieme Verlag KG Stuttgart - New York.
- You, Mei,Xiong, Juan,Zhao, Yun,Cao, Lei,Wu, Shi-Biao,Xia, Gang,Hu, Jin-Feng
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body text
p. 1939 - 1943
(2012/06/15)
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- Four novel furanocoumarin glucosides, candinosides A, B, C and D, from Heracleum candicans Wall
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Four novel furanocoumarin glucosides, candinosides A, B, C and D (1-4), were isolated from the roots of Heracleum candicans Wall. Their structures were established using chemical and spectral methods.
- Inoue, Atsuko,Shibano, Makio,Taniguchi, Masahiko,Baba, Kimiye,Wang, Nian-He
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experimental part
p. 116 - 121
(2012/01/03)
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- Pharmaceutical Composition Useful as Acetylcholinesterase Inhibitors
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A pharmaceutical composition useful as acetylcholinesterase inhibitors. The present invention relates to pharmaceutical composition comprising the naturally occurring compounds selected from (±) Marmesin, Columbianetin, Dihydroxanthyletin and substituted coumarin derivatives of 7-allyloxy coumarin, 7-benzyloxy coumarin, 7-methoxy coumarin, 7-acetyloxy coumarin, 4-methyl-7-hydroxy coumarin and 4-methyl-7-acetyloxy coumarin. The said compositions posses a high degree of acetylcholinesterase inhibitory (AChE) property.
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Page/Page column 3
(2008/06/13)
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- Enantioselective total syntheses of (+)-decursin and related natural compounds using catalytic asymmetric epoxidation of an enone
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The enantioselective total syntheses of (+)-decursin (1) and related natural dihydropyranocoumarins (-)-prantschimgin (3), (+)-decursinol (4), and (+)-marmesin (5) were achieved for the first time using catalytic asymmetric epoxidation of an enone as the key step. Catalytic asymmetric epoxidation of the enone was effectively promoted by the novel multifunctional asymmetric catalyst generated from La(O-i-Pr)3, BINOL, and Ph3As=O in a 1:1:1 ratio to afford epoxide in 94% yield and 96% ee, which was recrystallized to give optically pure epoxide. After conversion to the common key intermediate (-)-peucedanol (7), all natural dihydropyranocoumarins were synthesized through palladium-catalyzed intramolecular C-O coupling reactions. A possible reaction mechanism of the catalytic asymmetric epoxidation of enones is also described based on X-ray analysis, laser desorption/ionization time-of-flight mass spectrometry, kinetic studies, and asymmetric amplification studies.
- Nemoto, Tetsuhiro,Ohshima, Takashi,Shibasaki, Masakatsu
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p. 6889 - 6897
(2007/10/03)
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- Enantioselective total syntheses of novel PKC activator (+)-decursin and its derivatives using catalytic asymmetric epoxidation of an enone
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The catalytic asymmetric total syntheses of (+)-decursin and three related natural products, (+)-decursinol, (-)-prantschimgin and (+)-marmesin, were achieved for the first time using catalytic asymmetric epoxidation of an enone as the key step. The catalytic asymmetric epoxidation of enone was found to be promoted effectively by novel multifunctional asymmetric catalyst generated from La(O-i-Pr)3, BINOL and O=AsPh3 in a 1:1:1 ratio to afford epoxide in 94% yield and 96% ee, which was recrystallized to give the optically pure epoxide. (C) 2000 Elsevier Science Ltd.
- Nemoto,Ohshima,Shibasaki
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p. 9569 - 9574
(2007/10/03)
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- Coumarins from Ferulago capillaris and F. brachyloba
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Four new coumarins, (+)-senecioylprangol, (-)-3'-senecioyloxymarmesin, (+)-3'-hydroxyprantschimgin and (+)-2''-senecioyloxymarmesin, besides 12 known coumarins have been isolated from two Ferulago species. Their structures have been established by spectroscopic methods and partial synthesis. New synthetic 3'-oxocoumarins are also described. There is a remarkable difference in the contents of the most abundant coumarins found in the roots of both species: osthol and aurapten are specific to F. capillaris and F. brachyloba, respectively. (C) 2000 Elsevier Science Ltd.
- Jimenez, Benedicto,Grande, Maria Concepcion,Anaya, Josefa,Torres, Pascual,Grande, Manuel
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p. 1025 - 1031
(2007/10/03)
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- Biological Activity of Marmesin and Demethylsuberosin against a Generalist Herbivore, Spodoptera exigua (Lepidoptera: Noctuidae)
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No significant effects were observed in bioassays designed to measure impact of the furanocoumarin precursors demethylsuberosin and marmesin on typical physiological parameters (survival and development rate) of the generalist herbivore, Spodoptera exigua (Huebner). The linear furanocoumarin psoralen did increase developmental times and reduce survival. All of these compounds were demonstrated to have significant behavioral (feeding deterrence) effects against both first and third instars of S. exigua in diet-incorporation bioassays. In tests initiated with first instars, significantly (P 0.05) more larvae preferred control diet to diet containing marmesin or psoralen on all five sample dates; control diets were significantly preferred to diets with demethylsuberosin on three of five sample dates. Similar results were observed for tests initiated with third instar larvae, but the avoidance of demethylsuberosin-containing diets was stronger. Therefore, assaying furanocoumarin precursors just for effects on growth and survival may not provide an accurate picture of the ecological importance of these compounds.
- Trumble, John T.,Millar, Jocelyn G.
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p. 2859 - 2864
(2007/10/03)
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- COUMARINS AND FERULOL ESTERS FROM CACHRYS SICULA
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Key Word Index-Cachrys sicula; Umbelliferae; furocoumarins; (-)-sprengelianin; ferulol esters. (-)-Sprengelianin, (-)-prantschimgin and other minor coumarins were isolated from the roots and/or the umbels of Cachrys sicula.The roots also afforded the monoterpene hydroxyaldehyde ferulol esterified to angelic, tiglic and senecioic acids.The (-)-enantiomer of sprengelianin (2'S) had not been reported previously.The coumarins saxalin and pabulenol and the aromatic aldehyde 2,3,4-trimethylbenzaldehyde were also identified but these substances are presumably artefacts.
- Grande, Manuel,Aguado, Maria T.,Mancheno, Balbino,Piera, Francisco
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p. 505 - 508
(2007/10/02)
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- THE COUMARIN COMPOSITION OF Seseli tortuosum
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The results are given of the identification of the known pyranocoumarin campestrinol (I), and the structures of four new coumarin derivatives have been studied - tortuosin (II), tortuosinin (III), tortuosinol (IV), and tortuosidin (V).On the basis of their spectral characteristics and chemical transformations, the corresponding structures have been established for compounds (II)-(V).
- Abyshev, A. Z.,Abyshev, D. Z.
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p. 668 - 672
(2007/10/02)
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