- Vanadium-Catalyzed Oxidative Intramolecular Coupling of Tethered Phenols: Formation of Phenol-Dienone Products
-
A mild and efficient method for the vanadium-catalyzed intramolecular coupling of tethered free phenols is described. The corresponding phenol-dienone products are prepared directly in good yields with low catalyst loadings. Electronically diverse tethered phenol precursors are well tolerated, and the catalytic method was effectively applied as the key step in syntheses of three natural products and a synthetically useful morphinan alkaloid precursor.
- Gilmartin, Philip H.,Kozlowski, Marisa C.
-
supporting information
p. 2914 - 2919
(2020/04/10)
-
- Synthesis and cytotoxic activities of hexyl-esters derivatives of gallic acid against MCF-7 cell line
-
Gallic acid is found in many plants, fruits, and foods where the anti-cancer activity is found. However, gallic acid has a problem on the high polarity and low bio availability. So, it takes molecular modifications in order to increase its lipophilicity, which is expected to increase bio availability and cytotoxic activity of gallic acid. Hexyl esters derivatives of gallic acid were synthesized and characterized by spectrometer 1H-NMR, 13C-NMR, mass spectrometry and infrared spectrophotometer (FTIR). All compounds were then evaluated for cytotoxic activity on MCF-7 cell line using MTT method. Compound cis-2′-hexenyl-3,4,5-trimethoxygallate (19) had the lowest IC50 value compared with gallic acid and other derivatives hexyl esters. IC50 value of cis-2′-hexenyl-3,4,5-trimethoxygallate (19) is 14.48 μg/ml. Compound (19) also has approached with IC50 values of gossypol as a positive control. Compound (19) is a potential compound to inhibit growth of MCF-7 cell line.
- Paramita, Rafika Indah,Arsianti, Ade,Radji, Maksum
-
p. 295 - 300
(2018/03/21)
-
- Synthesis and in vitro antimalarial activity of alkyl esters of gallate as a growth inhibitor of plasmodium falciparum
-
This study is aimed to synthesize alkyl esters gallate and determine its in vitro antimalarial activity against parasite Plasmodium falciparum. Fourteen compounds of alkyl esters gallate were synthesized by esterification of the carboxyl group of gallic acid with a series of alkyl alcohols, as well as methoxylation of the hydroxy groups on the aromatic ring of gallic acid. Antimalarial activity of the synthesized alkyl esters gallate were expressed by IC50 value, with gallic acid as an original compound and artemisin as a positive control. Compared to gallic acid, eleven synthesized compounds of alkyl esters gallate, have a greater antimalarial activity against Plasmodium falciparum. On the other hand, three compounds, that are propyl gallate, butyl gallate and trimethoxy methyl gallate, showed a lower antimalarial activity. Moreover, compared to gallic acid (IC50: 194.86 mM) and artemisin (IC50: 0.5 mM), two synthesized compounds of alkyl gallates, namely methyl gallate and hexyl gallate exhibited the stronger antimalarial activity against Plasmodium falciparum, with IC50 value of 0.03 mM and 0.11 mM, respectively. Our result clearly demonstrated that methyl gallate and hexyl gallate as a promising candidate for the new antimalarial agents.
- Arsianti, Ade,Astuty, Hendri,Fadilah,Simadibrata, Daniel Martin,Adyasa, Zoya Marie,Amartya, Daniel,Bahtiar, Anton,Tanimoto, Hiroki,Kakiuchi, Kiyomi
-
p. 655 - 662
(2018/05/28)
-
- Bioinspired Total Synthesis of Bussealin e
-
The first total synthesis of bussealin E, a natural product with a unique cycloheptadibenzofuran scaffold, is reported. A strategy inspired by a proposed biosynthesis was employed whereby a diphenylpropane derivative underwent an oxidative phenolic coupling to forge the tetracyclic ring system. The synthesis of the diphenylpropane featured a key sp2-sp3 Hiyama coupling between a vinyldisiloxane and a benzylic bromide.
- Twigg, David G.,Baldassarre, Leonardo,Frye, Elizabeth C.,Galloway, Warren R. J. D.,Spring, David R.
-
supporting information
p. 1597 - 1599
(2018/03/23)
-
- A Regio- and Diastereoselective Anodic Aryl–Aryl Coupling in the Biomimetic Total Synthesis of (?)-Thebaine
-
The biosynthesis of thebaine is based on the regioselective, intramolecular, oxidative coupling of (R)-reticuline. For decades, chemists have sought to mimic this coupling by using stoichiometric oxidants. However, all approaches to date have suffered from low yields or the formation of undesired regioisomers. Electrochemistry would represent a sustainable alternative in this respect but all attempts to accomplish an electrochemical synthesis of thebaine have failed so far. Herein, a regio- and diastereoselective anodic coupling of 3′,4′,5′-trioxygenated laudanosine derivatives is presented, which finally enables electrochemical access to (?)-thebaine.
- Lipp, Alexander,Ferenc, Dorota,Gütz, Christoph,Geffe, Mario,Vierengel, Nina,Schollmeyer, Dieter,Sch?fer, Hans J.,Waldvogel, Siegfried R.,Opatz, Till
-
supporting information
p. 11055 - 11059
(2018/08/21)
-
- Ruthenium-Catalyzed Hydroarylation and One-Pot Twofold Unsymmetrical C?H Functionalization of Arenes
-
A methyl phenyl sulfoximine (MPS) is used as a directing group in the ruthenium-catalyzed intramolecular hydroarylation of alkene-tethered benzoic acid derivatives to afford dihydrobenzofurans and indolines in good to excellent yields. A one-pot, unsymmetrical, twofold C?H functionalization involving intramolecular C?C and intermolecular C?C/C?N bond formations is successfully demonstrated by using a single set of catalytic reaction conditions, which is unprecedented thus far. A novel isoquinolone-bearing dihydrobenzofuran is constructed through an unsymmetrical twofold C?H functionalization.
- Ghosh, Koushik,Ramesh, E.,Rit, Raja K.,Sahoo, Akhila K.
-
supporting information
p. 7821 - 7825
(2016/07/07)
-
- Chalcone derivative, preparing method, pharmaceutical composition and application
-
The invention relates to a chalcone derivative, a preparing method, a pharmaceutical composition and application, provides a compound with the general formula I, and pharmaceutically-acceptable salt or solvate or polymorphic substances or metabolites or prodrugs of the compound, and further provides a preparing method of the compound of the structure shown in the general formula I, a pharmaceutical composition including the substance, and application of the substance in preparing medicine for treating or preventing inflammation. The general formula I is shown in the description, wherein R1, R2, R3, R4, R5, R6, R7, R8 and R9 are H, substituted or unsubstituted C1-C4 alkyl, hydroxyl, alkoxy, amino, halogen, C1-C4 substituted acylamino and C1-C4 acyl; R11 and R12 are substituted or unsubstituted C1-C4 alkyl.
- -
-
Paragraph 0096; 0097
(2017/02/09)
-
- 3,5-dihydroxy-4-trifluoromethoxybenzyl alcohol (3,5-dihydro x y-4-metho x ybenzylalcohol) synthesis method (by machine translation)
-
PROBLEM TO BE SOLVED: earpick not derived from a so-called new antioxidant and anti-oxidant composition 3,5-dihydroxy-4-efficient trifluoromethoxybenzyl alcohol, to provide a method for synthesizing high purity. SOLUTION: subgallate dimethyl formamide suc
- -
-
Paragraph 0023-0027
(2017/04/11)
-
- Cross-coupling reaction of saccharide-based alkenyl boronic acids with aryl halides: The synthesis of bergenin
-
A convenient synthetic pathway enabling D-glucal and D-galactal pinacol boronates to be prepared in good isolated yields was achieved. Both pinacol boronates were tested in a series of cross-coupling reactions under Suzuki-Miyaura cross-coupling conditions to obtain the corresponding aryl, heteroaryl, and alkenyl derivatives in high isolated yields. This methodology was applied to the formal synthesis of the glucopyranoside moiety of papulacandin D and the first total synthesis of bergenin. Building blocks with boron: A convenient synthetic route to D-glucal and D-galactal pinacol boronates was developed, and the boronates were used in cross-coupling reactions to generate the corresponding aryl, heteroaryl, and alkenyl derivatives in high yields (see scheme). This methodology was applied to the formal synthesis of the glucopyranoside moiety of papulacandin D and the total synthesis of bergenin.
- Parkan, Kamil,Pohl, Radek,Kotora, Martin
-
supporting information
p. 4414 - 4419
(2014/05/06)
-
- ANTIOXIDANT, ANTIOXIDANT COMPOSTION AND PRODUCTION METHOD THEREFOR
-
Problem To provide an antioxidant, an antioxidant composition, and a method for producing the antioxidant and the antioxidant composition, which feature a high content rate and degree of extraction of substances. These substances are taurine, glycogen, pr
- -
-
Paragraph 0064; 0065
(2013/11/19)
-
- Supramolecular gelation of alcohol and water by synthetic amphiphilic gallic acid derivatives
-
The supramolecular organogelation of alcohols was observed in relatively hydrophobic amphiphiles with a short oligo(ethylene glycol) unit and three long alkyl chains at room temperature, while the hydrogelation occurred in more hydrophilic gelators with a longer poly(ethylene glycol) unit and two long alkyl chains at various temperatures. When a hot aqueous solution of some of the synthetic hydrogelators was cooled down, the supramolecular hydrogel was formed at room temperature. In some other amphiphiles with less intermolecular interactivity in water at room temperature, a reverse phase transition of sol to gel was observed by elevating the temperature of their aqueous systems, especially below a physiological temperature, 37 °C. The supramolecular hydrogelation at a low or high temperature was dependent on a slight molecular modification of the synthetic amphiphiles.
- Tamiaki, Hitoshi,Ogawa, Keishiro,Enomoto, Keisuke,Taki, Kazutaka,Hotta, Atsushi,Toma, Kazunori
-
supporting information; experimental part
p. 1661 - 1666
(2010/04/24)
-
- Total synthesis of (±)-megistophylline I
-
(±)-Megistophylline I (1), carrying a dienone residue in the acridone framework, was synthesized using the Claisen rearrangement to introduce a prenyl group as a key step.
- Nishihama, Yuko,Ishikawa, Yuichi,Nishiyama, Shigeru
-
scheme or table
p. 2801 - 2804
(2009/09/28)
-
- Synthesis, crystal structure, and growth inhibition of human hepatoma cell (HepG2) of polyphenolic compounds based on gallates
-
Seven compounds (1-7) based on gallate were synthesized and characterized by elemental analysis, 1H NMR, and MS spectra. 2-(3,5-Dibenzyloxy-4- methoxy)phenyl-2-propanol (6) was a new compound. Methyl 3,5-dihydroxy-4- methoxybenzoate (3), methyl 3,5-dibenzyloxy-4-methoxybenzoate (4), 3,5-dibenzyloxy-4-methoxybenzyl alcohol (5), and compound 6 were structurally determined by single-crystal X-ray diffraction for the first time. Crystallography data for 3: space group P21212 1; a = 4.0750(8) A, b = 7.5880(15) A, c = 29.802(6) A; V = 921.5(3) A3 Z = 4. 4: space group P-1; a = 10.068(2) A b = 10.499(2) A, c = 11.388(2) A; α = 76.84(3)°, β= 66.79(3)°, γ = 64.10(3)°; V = 993.0(3) A3, Z = 2. 5: space group P-1; a = 8.1410(16) A, b = 8.7590(18) A, c = 12.879(3) A; α = 91.66(3)°, β= 94.69(3)°, γ = 91.73(3)°; V = 914.4(3) A3; Z = 2. 6: space group P21/c; a = 5.8100(12) A, b = 15.778(3) A, c = 23.237(5) A; β= 96.09(3)°; V = 2118.1(7) A3; Z = 4. All of the seven compounds were evaluated for the inhibition of growth of human hepatoma (HepG2) cells. Comparison with the positive-control 5-fluorouracil (IC50 51.6 μmol/L), 5 showed stronger cytotoxic activity with an IC50 around 15.3 μmol/L, while IC50 value of 3 was 90.3 μmol/L. The effect of slight structural variations in this series of compounds was found to cause a marked change in their activity against HepG2 cells.
- Xiao, Zhu-Ping,Fang, Rui-Qin,Shi, Lei,Ding, Hui,Xu, Chen,Zhu, Hai-Liang
-
p. 951 - 957
(2008/03/28)
-
- Total synthesis of two natural phenanthrenes: confusarin and a regioisomer
-
The title compounds were synthesized by radical cyclization of the corresponding stilbenes intermediates. The latter ones arose from a Wittig reaction in a stereoselective manner (Z isomer is either the only one or the major one). Confusarin (1) was prepared in 13 steps from gallic acid. Its regioisomer (2) was obtained in five steps from syringaldehyde.
- Radix, Sylvie,Barret, Roland
-
p. 12379 - 12387
(2008/03/13)
-
- Biomimetic synthesis of (±)-galanthamine and asymmetric synthesis of (-)-galanthamine using remote asymmetric induction
-
(±)-Galanthamine (1) was synthesized in excellent yield by applying PIFA-mediated oxidative phenol coupling of N-(4-hydroxy)phenethyl-N-(3′, 4′,5′-trialkoxy)benzyl formamide (15b) as a key step. Because of the symmetrical characteristics of the pyrogallol moiety in the substrate (15b), the phenol coupling resulted in a sole coupling product except for volatile components from the oxidizing agent. On the basis of the successful results of the above strategy, (-)-galanthamine (1) was synthesized by employing a novel remote asymmetric induction, where conformation of the seven-membered ring in the product of the phenol coupling was restricted by forming a fused-chiral imidazolidinone ring with D-phenylalanine on the benzylic C-N bond of the tri-O-alkylated gallyl amino moiety. The conformational restriction and successive debenzylation of the protected hydroxyl groups on the pyrogallol ring caused diastereoselective cyclization to yield a cyclic ether having the desired stereochemistry for the synthesis of (-)-1.
- Node, Manabu,Kodama, Sumiaki,Hamashima, Yoshio,Katoh, Takahiro,Nishide, Kiyoharu,Kajimoto, Tetsuya
-
p. 1662 - 1679
(2007/10/03)
-
- Multi-functionalization of gallic acid towards improved synthesis of α- and β-DDB
-
The synthesis of mono-, di- and trisubstituted gallic acids and their ester with similar or different groups including different acetal and ketals is described. Regioselective bromination on two ortho-positions of methyl gallate, which is very crucial for many organic syntheses, was achieved in high yield and purity. The α- and β-DDB were synthesized in high overall yield and purity from the regioselective bromoderivatives.
- Alam, Ashraful,Takaguchi, Yutaka,Ito, Hideyuki,Yoshida, Takashi,Tsuboi, Sadao
-
p. 1909 - 1918
(2007/10/03)
-
- Gallic acid metabolites are markers of black tea intake in humans
-
Gallic acid is one of the main phenolic components of black tea. The objective of this study was to identify urinary gallic acid metabolites with potential for use as markers of black tea intake. In an initial study, nine compounds, assessed by using gas chromatography-mass spectrometry, were found to increase in concentration in urine after 3 cups of black tea over 3 h. A subsequent study employed a controlled crossover design in which 10 subjects consumed 5 cups per day of black tea or water for 4 weeks in random order. Twenty-four hour urine samples were collected at the end of each period. Of the 9 candidate compounds identified in the initial study, only 3 were present at higher concentrations in urine of all 10 subjects during tea- drinking in comparison to water-drinking periods. These compounds were identified as 4-O-methylgallic acid, 3-O-methylgallic acid, and 3,4-O- dimethylgallic acid, all methyl ether derivatives of gallic acid. It is suggested that these compounds have the potential to be used as markers of black tea intake.
- Hodgson, Jonathan M.,Morton, Lincoln W.,Puddey, Ian B.,Beilin, Lawrence J.,Croft, Kevin D.
-
p. 2276 - 2280
(2007/10/03)
-
- Chemistry of opium alkaloids, 45. Improvements in the total synthesis of morphine
-
The chiral 1,2,3,4-tetrahydroisoquinoline intermediates in the Price and Beyerman routes to morphine, (+)-(R)-1-(3-hydroxy-4-methoxybenzyl)-6-methoxy- 1,2,3,4-tetrahydroisoquinoline (6) and (+)-(R)-1-(3,5-dibenzyloxy-4- methoxybenzyl)-6-methoxy-1,2,3,4-tetrahydroisoquinoline (5), were prepared in high ee by ruthenium-catalyzed asymmetric transfer hydrogenation of the corresponding imine precursors (Noyori method). The yield of the key raw material in the Beyerman route, 3,5-dibenzyloxy-4-methoxyphenylacetric acid (1), starting from gallic acid methyl ester (7) was improved by a factor of 5 over previously described syntheses. Key steps in the new procedure are the selective formation of methyl 3,5-dihydroxy-4-methoxybenzoate (9) via the 3,5-diacetate and an improved benzylation of the hydroxyl groups in 9.
- Meuzelaar, Gerrit J.,Van Vliet, Michiel C. A.,Maat, Leendert,Sheldon, Roger A.
-
p. 2315 - 2321
(2007/10/03)
-
- Selective hydroxy group protection of gallic acid
-
An efficient procedure allowing selective differentiation of the 4-hydroxy group of methyl gallate was reported.
- Zhu, Jieping,Chastanet, Jacqueline,Beugelmans, Rene
-
p. 2479 - 2486
(2007/10/03)
-
- Asymmetric Synthesis of (2S,3R) β-(4-F-3-NO2) phenyl Serine, D-(R)-4-methoxy-3,5-Bis tButyldimethylsiloxy Phenylglycine and Their Assemblage to C-O-D Ring of Vancomycin
-
The asymmetric synthesis of two appropriately functionalyzed non-proteinogenic amino acids 2 and 3 needed for the total synthesis of vancomycin was described.The assemblage of these amino acids into linear tripeptide followed by biary ether formation via intramolecular SNAr reaction led to the fully functionalized C-O-D ring vancomycin.
- Zhu, Jieping,Bouillon, Jean-Philippe,Singh, Girij Pal,Chastanet, Jacqueline,Beugelmans, Rene
-
p. 7081 - 7084
(2007/10/02)
-
- Intramolecular Oxidative Coupling of Aromatic Compounds. I Oxidation of Diphenolic Substrates
-
The synthesis of (2RS,3SR)-1-(3,5-dihydroxy-4-methoxyphenyl)-(4-hydroxy-3,5-dimethoxyphenyl)2,3-dimethylbutan-1-one (26) is described.Diphenolic oxidative coupling of (26) did not produce a eupodienone-type product.An aryltetralin derivative was formed in
- Krauss, Adrian S.,Taylor, Walter C.
-
p. 1307 - 1333
(2007/10/02)
-
- Synthesis of Perrottetin F and G, Two Linear Bis(bibenzyl) Ethers from Radula perrottetii.
-
Perrottetin F and G, two acyclic bis(bibenzyls) with an ether linkage were synthesized using Ulmann and Wittig reactions. - Keywords: Bis(bibenzyl) ether / Perrottetins / Radula perrottetii
- Mezey-Vandor, Gabriella,Nogradi, M.,Novikov, V. P.,Wiszt, A.,Kajtar-Peredy, Maria
-
p. 401 - 404
(2007/10/02)
-
- SYNTHESIS OF NATURAL POLYHYDROXYSTILBENES
-
A synthesis of several natural polyhydroxystilbenes is described.
- Cardona, Luz,Fernandez, Isabel,Garcia, Begona,Pedro, Jose R.
-
p. 2725 - 2730
(2007/10/02)
-
- Total Synthesis of Junipegenin-A, an Isoflavone from Juniperus macropoda
-
Junipegenin-A (1), a new isoflavone isolated from Juniperus macropoda has been synthesised in nine steps, starting from gallic acid.The key step is the oxidative rearrangement of the intermediate benzyloxychalkone (9) by thallium(III) nitrate to give acetal (10) followed by cyclisation to the corresponding isoflavone (1), identical (m.m.p., co-TLC and co-IR) with a natural sample.
- Sethi, M. L.,Taneja, S. C.,Dhar, K. L.,Atal, C. K.
-
p. 770 - 772
(2007/10/02)
-