- Gamma-bifendate intermediate, synthesis method thereof, and synthesis method of gamma-bifendate
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The invention discloses a gamma-bifendate intermediate, a synthesis method thereof, and a synthesis method of gamma-bifendate. The gamma-bifendate intermediate is 4-methoxy-5, 6-methylenedioxy-2-methoxycarbonyl phenylboronic acid, and based on the gamma-bifendate intermediate, the invention further provides a novel synthesis method of gamma-bifendate. Ullmann reaction is not adopted, and Suzuki-Miyaura reaction is introduced as a key step of asymmetric synthesis, so that synthesis is simple, isomeride does not occur, the preparation process is optimized and upgraded, reaction steps are reduced, and reaction conditions are optimized.
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Paragraph 0016; 0045; 0048
(2021/08/07)
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- Synthesis method of 2-bromo-3, 4-methylenedioxy-5-methoxybenzoic acid methyl ester
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The invention belongs to the field of chemical pharmacy, and specifically discloses a preparation method of 2-bromo-3, 4-methylenedioxy-5-methoxybenzoic acid methyl ester. The preparation method comprises the following steps: by taking gallic acid as a ra
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- Synthetic method of bifendate intermediate
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The invention belongs to the field of chemical pharmacy, and particularly discloses a synthesis method of a bifendate intermediate, and the method comprises the following steps: by using gallic acid as a raw material, carrying out esterification reaction
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Paragraph 0016; 0019-0021; 0024-0026; 0029-0030
(2020/04/22)
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- An improved method for the synthesis of γ-DDB
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A mild and efficient method for the synthesis γ-DDB has been developed through anhydride-linker assisted intramolecular Ullmann reaction. Highly regioselective bromination of differentially protected gallate was realized by virtue of the introduction of NBS.
- Song, Chuanjun,Zhao, Peng,Hu, Zhiqiang,Shi, Shuai,Cui, Yanmei,Chang, Junbiao
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supporting information; experimental part
p. 2297 - 2298
(2010/06/16)
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- Total synthesis of graphislactones A, C, D, and H, of ulocladol, and of the originally proposed and revised structures of graphislactones e and F
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Graphislactones A-H and the structurally related ulocladol are highly oxygenated resorcylic lactones produced by lichens and fungi. We present total syntheses of graphislactones A, C-F, H and of ulocladol. Graphislactones E, F, and H were synthesized for the first time. The spectra of graphislactones E and F synthesized as the originally proposed structures were not in agreement with published data. Consequently, revised structures for these compounds are proposed, whose correctness is unambiguously proven by total synthesis and comparison of the spectroscopic data. Key steps in all syntheses are Suzuki couplings for the construction of the central biaryl bond and Dakin reactions to supply further hydroxy groups required in these highly oxygenated substrates. Graphislactones A, C, and H, acylated graphislac- tone D and ulocladol were prepared in 8-11 steps with 7-20% yield starting with purchasable compounds, where the longest linear sequence consists of 5-9 steps. The syntheses are thus significantly shorter than the previously published syntheses of graphislactones A-D and of ulocladol. Graphis- lactones E and F were synthesized in 8 steps, where the longest linear sequences consist of 6 and 5 steps, respectively. They were isolated as the respective acetylated compounds with 25 and 10% yield.
- Altemoeller, Martina,Gehring, Timo,Cudaj, Judith,Podlech, Joachim,Goesmann, Helmut,Feldmann, Claus,Rothenberger, Alexander
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experimental part
p. 2130 - 2140
(2009/09/29)
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- Isolation, synthesis, and neurite outgrowth-promoting activity of illicinin A from the flowers of Illicium anisatum
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Two new prenylated C6-C3 compounds, illicinin A (1) and (4S)-illicinone I (2), were isolated from the flowers of Illicium anisatum. The structures of the new compounds were elucidated by spectroscopic methods. The absolute structure of (4S)-illicinone I was determined by comparing its CD spectrum and specific rotation with those of (4S)-illicinone A (4). Illicinin A (1) and 4-allyl-2,6-dimethoxy-3-(3-methylbut-2-enyl)phenol (3) were found to exhibit neurite outgrowth-promoting activity at concentrations ranging from 0.1 to 10 μM in primary cultured rat cortical neurons. Illicinin A and its derivatives were synthesized for structure-activity relationship studies by employing sequential Stille reactions to introduce a prenyl and an allyl group to the benzene ring, thereby indicating that an allylphenyl moiety in the molecule of 1 is essential for its neurotrophic properties.
- Takaoka, Shigeki,Takaoka, Noriko,Minoshima, Yuka,Huang, Jian-Mei,Kubo, Miwa,Harada, Kenichi,Hioki, Hideaki,Fukuyama, Yoshiyasu
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experimental part
p. 8354 - 8361
(2009/12/26)
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- Synthesis of unsymmetrical biphenyls as potent cytotoxic agents
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Twenty-six unsymmetrical biphenyls were synthesized and evaluated for cytotoxic activity against DU145, A549, KB and KB-Vin tumor cell lines. Three compounds 27, 35 and 40 showed very potent activity against the HTCL panel with an IC50 value range of 0.04-3.23 μM. In addition, fourteen active compounds were all more potent against the drug-resistant KB-Vin cell line than the parental KB cell line. Preliminary SAR analysis indicated that two bulky substituents on the 2,2′-positions of unsymmetrical biphenyl skeleton are necessary and crucial for in vitro anticancer activity, thus providing a good starting point to develop unsymmetrical biphenyls as novel anticancer agents.
- Wu, Gang,Guo, Huan-Fang,Gao, Kun,Liu, Yi-Nan,Bastow, Kenneth F.,Morris-Natschke, Susan L.,Lee, Kuo-Hsiung,Xie, Lan
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scheme or table
p. 5272 - 5276
(2009/05/07)
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- Multi-functionalization of gallic acid towards improved synthesis of α- and β-DDB
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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
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p. 1909 - 1918
(2007/10/03)
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- Efficient synthesis of γ-DDB
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Synthesis of γ-DDB, which is another family member of α-DDB (dimethyl 4,4′-dimethoxy-5,6,5′,6 ′- dimethylenedioxybiphenyl-2,2′- dicarboxylate), is described. The unsymmetric isomer (γ-DDB) was constructed by a linker-directed intramolecular Ullmann coupling reaction, followed by the cleavage of the linker and re-esterification.
- Chang, Junbiao,Guo, Xiaohe,Cheng, Senxiang,Guo, Ruiyun,Chen, Rongfeng,Zhao, Kang
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p. 2131 - 2136
(2007/10/03)
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- Synthesis, separation, and theoretical studies of chiral biphenyl lignans (α- and β-DDB)
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Two biphenyl lignans, α- and β-DDB (1 and 2, respectively) were efficiently synthesized without contamination by other regio-isomers. The different yields of the Ullmann coupling reactions for the synthesis of 1 and 2 were rationalized by calculating steric hindrance, stability, entropy change, and heat-of-formation values. The enantiomers of 1 and 2 were readily separated by HPLC on a chiral stationary phase. Their configurations were assigned based on the Cotton effect of the authentic natural products.
- Chang, Junbiao,Chen, Rongfeng,Guo, Ruiyun,Dong, Chunhong,Zhao, Kang
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p. 2239 - 2246
(2007/10/03)
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- Synthesis and antihepatotoxicity of some Wuweizisu analogues
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A preparation of dimethyl 4,4'-dimethoxy-5,6,5',6'-dimethylenedioxybiphenyl-2,2'-dicarboxylate (VII) was readily achieved. It provided the advantages of specificity, simplicity, and efficiency in reactions. 6-Phenyl-3,9-dimethoxy-1,2-methylenedioxy-10,11-methylenedioxy-6,7- dihydro-5H-dibenz(c, e)azepin (X) was successfully synthesized from VII (DDB) and its liver-protective property proved to be more effective than DDB and silymarin in the in vitro test of carbon tetrachloride-induced damage of primary cultured rat hepatocytes.
- Wu,Chen,Chang,Chen,Lee
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p. 353 - 358
(2007/10/02)
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- Novel biphenyl derivative and preparation and use thereof
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The present invention relates to a novel biphenyl derivative having a liver ailment-moderating action and effective as a remedy for acute hepatitis and chronic hepatitis, a process for the preparation of this biphenyl derivative and a liver ailment-moderating agent comprising this diphenyl derivative as an effective ingredient. This diphenyl derivative is represented by the following formula: STR1 wherein R0 and R1 independently stand for a lower alkyl group or R0 and R1 together represent a group O=C2 stands for an alkyl group having 1 to 3 carbon atoms, and R3 and R4 independently stand for a hydrogen atom or a lower alkyl group.
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