- Inhibition of tyrosinase by flavonoids, stilbenes and related 4- substituted resorcinols: Structure-activity investigations
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Several flavonoids, stilbenes and related 4-substituted resorcinols, obtained from Artocarpus incisus and other plants or synthesized, were tested for their inhibitory activity against tyrosinase. The structure-activity relationships suggested that specific natural or synthesized compounds having the 4-substituted resorcinol skeleton have potent tyrosinase inhibitory ability. Kinetic studies have indicated that specific compounds having the 4- substituted resorcinol skeleton exhibit competitive inhibition of the oxidation of DL-β-(3,4-dihydroxyphenyl)alanine (DL-DOPA) by mushroom tyrosinase. These findings could lead to the design and discovery of new tyrosinase inhibitors.
- Shimizu, Kuniyoshi,Kondo, Ryuichiro,Sakai, Kokki
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- Efficient hydro-deoxygenation of lignin derived phenolic compounds over bifunctional catalysts with optimized acid/metal interactions
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Efficient hydro-deoxygenation (HDO) of lignin derived phenolic compounds was a challenging task due to the incompatibility of the phenolic feedstock and the current hydro-processing catalysts. In this paper, hydro-deoxygenation of lignin derived phenolic compounds over a series of bifunctional catalysts with different metal/acid interactions was firstly carried out. It was found that the distance between the acidic site and noble metal played an important role in the catalytic performance of phenolic hydro-deoxygenation. A highly stable bifunctional catalyst for hydro-deoxygenation of lignin derived phenolic compounds was obtained through simple selective deposition of Pt on alumina in a commonly used Al2O3-ZSM-5 nanocomposite. The bifunctional catalyst retained its complete deoxygenation capacity for more than 500 h. The catalyst can also be used for the HDO of various phenolic model compounds and real bio-oil derived from lignin. A correction of the generally accepted the closer the better criterion in metal/acid bifunctional catalysts when used in bio-oxygenate HDO was also discussed.
- Ju, Chao,Li, Mingrui,Fang, Yunming,Tan, Tianwei
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supporting information
p. 4492 - 4499
(2018/10/24)
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- Discovery and SAR study of hydroxyacetophenone derivatives as potent, non-steroidal farnesoid X receptor (FXR) antagonists
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Compound 1 (IC50 = 35.2 ± 7.2 μM), a moderate FXR antagonist was discovered via high-throughput screening. Structure-activity relationship studies indicated that the shape and the lipophilicity of the substituents of the aromatic ring affect the activity dramatically, increasing the shape and the lipophilicity of the substituents of the aromatic ring enhances the potency of FXR antagonists. Especially, when the OH at C2 position of the aromatic ring was replaced by the OBn substituent (analog 2b), its activity could be improved to IC50 = 1.1 ± 0.1 μM. Besides, the length of the linker and the tetrazole structure are essential for retaining the activity.
- Liu, Peng,Xu, Xing,Chen, Lili,Ma, Lei,Shen, Xu,Hu, Lihong
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p. 1596 - 1607
(2014/03/21)
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- Combinatorial synthesis and in vitro evaluation of a biaryl hydroxyketone library as antivirulence agents against mrsa
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Antibiotic resistance coupled with decreased development of new antibiotics necessitates the search for novel antibacterial agents. Antivirulence agents offer an alternative to conventional antibiotics. In this work, we report on a family of small-molecule antivirulence agents against methicillin-resistant Staphylococcus aureus (MRSA), the most widespread bacterial pathogen. Structure-activity relationship studies led to the development of a concise synthesis of a 148-member biarylhydroxyketone library. An acylation bond-forming process afforded resorcinols (1) and aryloxy acetonitriles (2) as synthons. A Lewis-acid-activated Friedel-Crafts' acylation step involving a nitrile functionality of 2 by ZnCl2, followed by nucleophilic attack by 1 was executed to obtain biaryl hydroxyketones in excellent yields. A large number of products crystallized. This strategy affords a range of biarylhydroxyketones in a single step. This is the first collective synthetic study documenting access to this class of compounds through a single synthetic operation. In vitro efficacy of compounds in this library was evaluated by a rabbit erythrocyte hemolysis assay. The most efficacious compound, 4f-12, inhibits hemolysis by 98.1 ± 0.1% compared to control in the absence of the compound.
- Yu, Guanping,Kuo, David,Shoham, Menachem,Viswanathan, Rajesh
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supporting information
p. 85 - 91
(2014/03/21)
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- ANTI-VIRULENCE COMPOSITIONS AND METHODS
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A method of reducing the virulence of a bacterium that expresses accessory gene regulator A (AgrA) or an ortholog of AgrA includes administering to the bacterium an amount of a pharmaceutical composition effective to inhibit the synthesis of one or more virulence factors by the bacterium, the pharmaceutical composition including an AgrA antagonist.
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Paragraph 0143
(2014/05/07)
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- PROCESS FOR STRAIGHTENING KERATIN FIBRES WITH A HEATING MEANS AND DENATURING AGENTS
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The invention relates to a process for straightening keratin fibres, comprising: (i) a step in which a straightening composition containing at least two denaturing agents is applied to the keratin fibres, (ii) a step in which the temperature of the keratin fibres is raised, using a heating means, to a temperature of between 110 and 250° C.
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- Process for the synthesis of alkylresorcinols
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The invention provides a process for the production of 4-(C2-C16)alkylresorcinol. 4-(C2-C16)alkylresorcinol is produced by reacting resorcinol with a (C2-C16)alkyloic acid in the presence of a zinc chloride catalyst to produce an intermediate comprising a 4-(C2-C16)acylresorcinol and zinc ions. Then the intermediate is adjusted such that the zinc ion content is from about 0.1 to about 150 parts per million based on the weight of the intermediate to form an adjusted intermediate. Then the produced 4-(C2-C16)acylresorcinol is hydrogenated in the presence of the zinc ions and a base metal hydrogenation catalyst to produce a crude product comprising 4-(C2-C16)alkylresorcinol, which may thereafter be isolated.
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Page/Page column 3
(2008/06/13)
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- Nematic phase formed by V-shaped molecules
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In the paper there are presented synthesis and properties of new banana-shaped molecules that are ester resorcinol derivatives. The compounds with lateral alkyl substituent at the 4-position of the resorcinol ring exhibit the liquid crystalline nematic phase. Some of the synthesised compounds are able to induce the anticlinic S*CA phase that proves their bent molecular shape.
- Szydlowska, Jadwiga,Matraszek, Joanna,Mieczkowski, Jozef,Gorecka, Ewa,Pociecha, Damian
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p. 107 - 115
(2007/10/03)
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- Antifungal Activity of 2,4-Dihydroxyacylophenones and Related Compounds
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The antifungal activity of 2,4-dihydroxyacylophenones and related compounds against Trichophyton spp. and other fungi were investigated to determine their structure-activity relationships.The activity of these compounds was found to be closely related to the length of the acyl and alkyl substituents attached to the 1,3-dihydroxybenzene moiety.In addition, differences in activity were observed depending on the position of the alkyl substituents and on the number of substituents attached to the 1,3-dihydroxybenzene moiety.Some compounds tested showed potent antifungal activity against Trichophyton spp. and other fungi that was more active than amphotericin B.
- Mizobuchi, Shigeyuki,Sato, Yuko
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p. 1327 - 1334
(2007/10/02)
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