- Study of acylhydrazone derivatives with deoxygenated seven-membered rings as potential β-ketoacyl-acyl carrier protein synthase III (FabH) inhibitors
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Fatty acid biosynthesis is essential for bacterial survival. FabH, β-ketoacyl-acyl carrier protein (ACP) synthase III, is a particularly attractive target, since it is central to the initiation of fatty acid biosynthesis and highly conserved among Gram-positive and Gram-negative bacteria. Following previous studies, a series of acylhydrazone derivatives with deoxygenated rings were synthesized in this work. For all of the 36 analogues synthesized, studies using H NMR, C NMR, MS and elemental analyses were conducted. Their biological activities were also evaluated against two Gram-negative bacterial strains: E. coli and P. aeruginosa, and two Gram-positive bacterial strains: B. subtilis and S. aureus by the MTT method as potential FabH inhibitors. The resulting compound F18 showed the highest antibacterial activity with MIC values of 1.56-3.13 μg mL-1 against the tested bacterial strains and was found to be the most potent E. coli FabH inhibitor with an IC50 value of 2.0 μM. Molecular modeling simulation studies were performed in order to predict the biological activities of compound F18 into the E. coli FabH active site.
- Zhou, Yang,Luo, Yin,Yang, Yu-Shun,Lu, Liang,Zhu, Hai-Liang
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- TWO CHROMENES AND A PRENYLATED BENZOIC ACID DERIVATIVE FROM PIPER ADUNCUM
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In addition to stigmasterol, piperiton, methyl 2,2-dimethyl-2H-chromene-6-carboxylate, methyl 3-(2-hydroxy-3-methyl-3-butenyl)-4-hydroxy-benzoate and methyl (6S)-2-trans-6-hydroxy-2,6-dimethyl-2,7-octadienoate, three new natural products were isolated fro
- Orjala, Jimmy,Erdelmeier, C. A. J.,Wright, Anthony D.,Rali, Topul,Sticher, Otto
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- Oxidative dimers produced from protocatechuic and gallic esters in the DPPH radical scavenging reaction
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DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging reactions of protocatechuic and gallic acids, and their methyl esters, have been investigated by NMR. In acetone, methyl protocatechuate was gradually converted to a Diels-Alder adduct of two molecul
- Kawabata, Jun,Okamoto, Yasuko,Kodama, Asuka,Makimoto, Terumasa,Kasai, Takanori
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- The phenol ortho-oxygenation by mononuclear copper(I) complexes requires a dinuclear μ-η2:η2-peroxodicopper(II) complex rather than mononuclear CuO2 species
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The mononuclear complex [Cu(L)]+ performs the orthooxygenation of an exogeneous phenol through the formation of a dinuclear μ-η2:η2-peroxodicopper(II) intermediate, which is so far the only type of copper-dioxygen complex
- Battaini, Giuseppe,De Carolis, Marco,Monzani, Enrico,Tuczek, Felix,Casella, Luigi
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- Reversible dioxygen binding and phenol oxygenation in a tyrosinase model system
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The complex [Cu2(L-66)]2- (L-66 = a,a'-bis{bis[2-(1'-methyl-2'- benzimidazolyl)ethyl]amino}-m-xylene) undergoes fully reversible oxygenation at low temperature in acetone. The optical [λ(max) = 362 (ε 15000), 455 (ε 2000), and 550 nm
- Santagostini, Laura,Gullotti, Michele,Monzani, Enrico,Casella, Luigi,Dillinger, Renee,Tuczek, Felix
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- Structure-property-activity relationship of phenolic acids and derivatives. Protocatechuic acid alkyl esters
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The esterification of hydrophilic phenolic antioxidants is an efficient approach to enhance their solubility in apolar media. Herein, structurea property studies on the antiradical activity of a series of protocatechuic acid alkyl esters have been accomplished. The increase of the lipophilicity was shown to significantly improve the antioxidant activity of protocatechuic esters. Their efficiency as radical scavengers was evaluated using distinctive analytical methods, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) UV/visible method, electrochemistry, and differential scanning calorimetry. All the new alkyl protocatechuate antioxidants studied possessed better radical-scavenging capacity than the natural antioxidant protocatechuic acid. This work has shown that the alkyl ester side chain markedly influences the lipophilicity of this type of phenolic system without disturbing the core of the molecule responsible for antioxidant activity. The data on the antioxidant activity obtained using the different analytical methods correlated well with each other and have revealed the interesting antioxidant potential of alkyl esters of protocatechuic acid.
- Reis, Bruno,Martins, Marta,Barreto, Barbara,Milhazes, Nuno,Garrido, E. Manuela,Silva, Paulo,Garrido, Jorge,Borges, Fernanda
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- A Tyrosinase Model System. Phenol ortho-Hydroxylation by a Binuclear Three-coordinate Copper(I) Complex and Dioxygen
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The binuclear three-coordinate copper(I) complex 1 derived from a polybenzimidazole ligand exhibits tyrosinase-like activity an exogenous phenols.
- Casella, Luigi,Gullotti, Michele,Radaelli, Roberto,Gennaro, Patrizia Di
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- Ethyl acetate as a co-solvent and sacrificial ester in the aluminum triiodide promoted chemoselective demethylation of methyl vanillate
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A synthetic approach towards methyl protocatechuate via chemoselective ether cleavage of methyl vanillate without affecting the carboxylate group is disclosed utilizing a ternary reagent system consisting of aluminum triiodide, 1,3-diisopropylcarbodiimide and ethyl acetate. Ethyl acetate serves as a co-solvent and sacrificial ester. Methyl isovanillate, ethyl vanillate and methyl feruate were analogously demethylated to give methyl protocatechuate, ethyl protocatechuate and methyl caffeate, respectively, in fair to excellent yields.
- Tian, Juan,Yi, Cuicui,Fang, Huasheng,Sang, Dayong,He, Zhoujun,Wang, Jiahui,Gan, Yongjiang,An, Qing
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- Plasma-Induced Degradation of Quercetin Associated with the Enhancement of Biological Activities
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Nonthermal plasma is a promising technology to improve the safety and to extend the shelf-life of various minimally processed foods. However, research on plasma-induced systemic degradation related to changes in chemical structure and biological activity is still very limited. In this study, the enhancement of biological activity and the mechanism of degradation of the most common type of flavonol, quercetin, induced by a dielectric barrier discharge (DBD) plasma were investigated. Quercetin is dissolved in methanol and exposed to nonthermal DBD plasma for 5, 10, 20, and 30 min. The quercetin treated with the plasma for 20 min showed rapidly increased α-glucosidase inhibitory and radical scavenging activities compared to those of parent quercetin. The structures of the degradation products 1-3 from the quercetin treated with the plasma for 20 min were isolated and characterized by interpretation of their spectroscopic data. Among the generated products, (±)-alphitonin (1) exhibited significantly improved antidiabetic and antioxidant properties compared to those of the parent quercetin. The antidiabetic and antioxidant properties were measured by α-glucosidase inhibition and 1,1-diphenyl-2-picrylhydrazyl radical scavenging assays. These results suggested that structural changes in quercetin induced by DBD plasma might be attributable to improving the biological activity.
- Kim, Tae Hoon,Lee, Jaemin,Kim, Hyun-Joo,Jo, Cheorun
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- Kinetic Evaluation of Phenolase Activity of Tyrosinase Using Simplified Catalytic Reaction System
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A very simple tyrosinase reaction system has been developed using borate anion as a trapping agent of catechols and hydroxylamine as an external reductant to evaluate the phenolase activity without the interference of catecholase activity. Reactivities of variously para-substituted phenols in this system were compared directly to those of the phenols in the model reactions, demonstrating that the enzymatic oxygenation reaction of phenols proceeds via the same mechanism as the model reaction, that is, electrophilic aromatic substitution mechanism. Copyright
- Yamazaki, Shin-Ichi,Itoh, Shinobu
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- Benzodioxane-Benzamides as Antibacterial Agents: Computational and SAR Studies to Evaluate the Influence of the 7-Substitution in FtsZ Interaction
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FtsZ is a crucial prokaryotic protein involved in bacterial cell replication. It recently arose as a promising target in the search for antimicrobial agents able to fight antimicrobial resistance. In this work, going on with our structure-activity relationship (SAR) study, we developed variously 7-substituted 1,4-benzodioxane compounds, linked to the 2,6-difluorobenzamide by a methylenoxy bridge. Compounds exhibit promising antibacterial activities not only against multidrug-resistant Staphylococcus aureus, but also on mutated Escherichia coli strains, thus enlarging their spectrum of action toward Gram-negative bacteria as well. Computational studies elucidated, through a validated FtsZ binding protocol, the structural features of new promising derivatives as FtsZ inhibitors.
- Straniero, Valentina,Sebastián-Pérez, Victor,Hrast, Martina,Zanotto, Carlo,Casiraghi, Andrea,Suigo, Lorenzo,Zdovc, Irena,Radaelli, Antonia,De Giuli Morghen, Carlo,Valoti, Ermanno
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- Last-Step Enzymatic [18F]-Fluorination of Cysteine-Tethered RGD Peptides Using Modified Barbas Linkers
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We report a last-step fluorinase-catalyzed [18F]-fluorination of a cysteine-containing RGD peptide. The peptide was attached through sulfur to a modified and more hydrophilic variant of the recently disclosed Barbas linker which was itself link
- Zhang, Qingzhi,Dall'Angelo, Sergio,Fleming, Ian N.,Schweiger, Lutz F.,Zanda, Matteo,O'Hagan, David
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- Studies toward the construction of the allyltrisulfide component in esperamicin-A1 from 5-ketoshikimic acid derivatives: Part 1
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The conversion of keto ester 1, obtained in either enantiomeric form from (-)-quinic acid, to its corresponding enol silyl ether 4 was examined as the first step to construct the allyl trisulfide unit found in esperamicin A1. Under different co
- Piguel, Sandrine,Ulibarri, Gerardo,Grierson, David S.
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- Synthesis of Protected 3,4- And 2,3-Dimercaptophenylalanines as Building Blocks for Fmoc-Peptide Synthesis and Incorporation of the 3,4-Analogue in a Decapeptide Using Solid-Phase Synthesis
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3,4-Dimercaptophenylalanines and 2,3-dimercaptophenylalanines have been synthesized for the first time by nucleophilic substitution of a protected aminomalonate on 3,4- and 2,3-dimercaptobenzyl bromide derivatives. The dithiol functions were protected as thioketals, and the key precursors, diphenylthioketal-protected dimercaptobenzyl bromides, were synthesized via two distinct routes from either dihydroxy benzoates or toluene-3,4-dithiol. Racemic mixtures of the fully protected amino acids were separated by chiral HPLC into the corresponding enantiomers. The absolute configuration of both 3,4- and 2,3-analogues could be assigned based on X-ray crystallography and VCD/DFT measurements. Thioketal groups were deprotected upon reaction with mercury oxide and aqueous tetrafluoroboric acid followed by treatment with H2S gas under an argon atmosphere to obtain the corresponding dimercapto amino acids. The optically pure l-Fmoc-protected 3,4-analogue (S- enantiomer) was successfully incorporated into a decapeptide using standard solid-phase peptide synthesis. Therefore, dithiolene-functionalized peptides are now accessible from a simple synthetic procedure, and this should afford new molecular tools for research into the catalysis, diagnostic, and nanotechnology fields.
- Banerjee, Isita,Ghosh, Keshab Ch.,Oheix, Emmanuel,Jean, Marion,Naubron, Jean-Valère,Réglier, Marius,Iranzo, Olga,Sinha, Surajit
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supporting information
p. 2210 - 2223
(2021/02/26)
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- Synthesis and application of acrylic resin based on protocatechuic acid
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The invention discloses synthesis and application of acrylic resin based on protocatechuic acid. According to the method, protocatechuic acid is used as a raw material, firstly, alcohol is used for esterification, and then the raw material and acryloyl chloride are synthesized into the protocatechuic acid-based acrylic resin monomer (M) through a one-pot method. And the acrylic resin based on protocatechuic acid is used for modifying polymethyl methacrylate (organic glass). The resin monomer is copolymerized with methyl methacrylate (MMA), the glass transition temperature (Tg) is increased along with the increase of the M content, and when the M content is 50%, the Tg of the copolymer is 159.6 DEG C (the heat resistance is improved by 51 DEG C). The Td5 of the copolymer is 358 DEG C (increased by 48 DEG C), and the residual carbon rate is 12.57%. In addition, the copolymerization product also shows the characteristic of absorbing short-wave blue light. The synthesis method provided by the invention is mild in reaction condition and relatively high in yield, and has a relatively great application prospect in the application field of optical electronics. The invention also widens the application range of biological resources.
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Paragraph 0049-0050
(2021/06/26)
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- Polyhydroxybenzoic acid derivatives as potential new antimalarial agents
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With more than 200 million cases and 400,000 related deaths, malaria remains one of the deadliest infectious diseases of 2021. Unfortunately, despite the availability of efficient treatments, we have observed an increase in people infected with malaria since 2015 (from 211 million in 2015 to 229 million in 2019). This trend could partially be due to the development of resistance to all the current drugs. Therefore, there is an urgent need for new alternatives. We have, thus, selected common natural scaffolds, polyhydroxybenzoic acids, and synthesized a library of derivatives to better understand the structure–activity relationships explaining their antiplasmodial effect. Only gallic acid derivatives showed a noticeable potential for further developments. Indeed, they showed a selective inhibitory effect on Plasmodium (IC50 ~20 μM, SI > 5) often associated with interesting water solubility. Moreover, this has confirmed the critical importance of free phenolic functions (pyrogallol moiety) for the antimalarial effect. Methyl 4-benzoxy-3,5-dihydroxybenzoate (39) has, for the first time, been recognized as a potential lead for future research because of its marked inhibitory activity against Plasmodium falciparum and its significant hydrosolubility (3.72 mM).
- Degotte, Gilles,Francotte, Pierre,Pirotte, Bernard,Frédérich, Michel
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- BENZOXAZINONE COMPOUNDS AS KLK5/7 DUAL INHIBITORS
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The present invention provides compounds and pharmaceutical compositions including the compounds for the treatment of a skin disease associated with proteolytic activity of one or more KLK proteases, wherein the compounds are according to formula (I): whe
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Paragraph 0143-0144; 0157-0159; 0176; 0192-0194
(2021/04/10)
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- Metabolite profile of Nectandra oppositifolia Nees & Mart. And assessment of antitrypanosomal activity of bioactive compounds through efficiency analyses
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EtOH extracts from the leaves and twigs of Nectandra oppositifolia Nees & Mart. shown activity against amastigote forms of Trypanosoma cruzi. These extracts were subjected to successive liquid-liquid partitioning to afford bioactive CH2Cl2 fractions. UHPL
- Conserva, Geanne A. Alves,Quiros-Guerrero, Luis M.,Costa-Silva, Thais A.,Marcourt, Laurence,Pinto, Erika G.,Tempone, Andre G.,Fernandes, Jo?o Paulo S.,Wolfender, Jean-Luc,Queiroz, Emerson F.,Lago, Jo?o Henrique G.
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- Cannabidiol derivative, preparation method and application thereof
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The invention discloses a cannabidiol derivative, a preparation method and application thereof, and belongs to the technical field of medicinal chemistry, wherein the cannabidiol derivative is obtained by taking cannabidiol as a main body through a synthesis means, and an anti-tumor activity determination result shows that the cannabidiol derivative prepared by the invention has an inhibition effect on lung cancer cell strains, human breast cancer cell strains, nasopharynx cancer and drug-resistant strains thereof.
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Paragraph 0027; 0035-0037; 0045-0047
(2021/07/28)
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- Iron-catalyzed arene C-H hydroxylation
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The sustainable, undirected, and selective catalytic hydroxylation of arenes remains an ongoing research challenge because of the relative inertness of aryl carbon-hydrogen bonds, the higher reactivity of the phenolic products leading to over-oxidized by-products, and the frequently insufficient regioselectivity. We report that iron coordinated by a bioinspired L-cystine-derived ligand can catalyze undirected arene carbon-hydrogen hydroxylation with hydrogen peroxide as the terminal oxidant. The reaction is distinguished by its broad substrate scope, excellent selectivity, and good yields, and it showcases compatibility with oxidation-sensitive functional groups, such as alcohols, polyphenols, aldehydes, and even a boronic acid. This method is well suited for the synthesis of polyphenols through multiple carbon-hydrogen hydroxylations, as well as the late-stage functionalization of natural products and drug molecules.
- Cheng, Lu,Wang, Huihui,Cai, Hengrui,Zhang, Jie,Gong, Xu,Han, Wei
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- NOVEL ISOINDOLINE DERIVATIVE, AND PHARMACEUTICAL COMPOSITION AND APPLICATION THEREOF
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Disclosed are a novel isoindoline derivative, a pharmaceutical composition and use thereof. The compound of formula I, or the pharmaceutically acceptable salt, solvate, polymorph, co-crystal, stereoisomer, isotopic compound, metabolite or prodrug thereof disclosed in the invention can regulate the generation and/or activity of PDE4 and/or TNF-α so as to effectively treat cancer and inflammatory diseases.
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Paragraph 0103; 0126; 0128-0129
(2020/01/22)
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- Bioorthogonal Ligation and Cleavage by Reactions of Chloroquinoxalines with ortho-Dithiophenols
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A bioorthogonal ligation and cleavage method via reactions of chloroquinoxalines (CQ) and ortho-dithiophenols (DT) is presented. Double nucleophilic substitutions of ortho-dithiophenols to chloroquinoxalines provide conjugates containing tetracyclic benzo[5,6][1,4]dithiino[2,3-b]quinoxaline with strong built-in fluorescence together with release of the other functional molecules. Three cleavable linkers were designed and successfully used in release of the molecules containing biotin from the protein conjugates. The CQ-DT bioorthogonal reactions can be applied for the bioorthogonal ligations, bioorthogonal cleavages, and trans-tagging of proteins, and show advantages of readily accessible unnatural orthogonal groups, appealing reaction kinetics (k2≈1.3 m?1 s?1), excellent biocompatibility of orthogonal groups, and high stability of conjugates. This complements previous bioorthogonal reactions and is a new route for protein-fishing applications and in-gel fluorescence analysis.
- Fu, Hua,Li, Hongyun,Li, Youshan,Lou, Zhenbang,Yang, Haijun,Zhao, Yufen
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supporting information
p. 3671 - 3677
(2020/02/04)
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- Anchimerically Assisted Selective Cleavage of Acid-Labile Aryl Alkyl Ethers by Aluminum Triiodide and N, N-Dimethylformamide Dimethyl Acetal
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Aluminum triiodide is harnessed by N,N-dimethylformamide dimethyl acetal (DMF-DMA) for the selective cleavage of ethers via neighboring group participation. Various acid-labile functional groups, including carboxylate, allyl, tert-butyldimethylsilyl (TBS), and tert-butoxycarbonyl (Boc), suffer the conditions intact. The method offers an efficient approach to cleaving catechol monoalkyl ethers and to uncovering phenols from acetal-type protecting groups such as methoxymethyl (MOM), methoxyethoxymethyl (MEM), and tetrahydropyranyl (THP) chemoselectively.
- Sang, Dayong,Yue, Huaxin,Zhao, Zhengdong,Yang, Pengtao,Tian, Juan
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p. 6429 - 6440
(2020/07/14)
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- Selective ether bond breaking method of aryl alkyl ether
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The invention discloses a selective aryl alkyl ether cracking method, which comprises that aryl alkyl ether, aluminum iodide and an additive are subjected to a selective ether bond cleavage reaction in an organic solvent at a temperature of -20 DEG C to a reflux temperature to generate phenol and derivatives thereof. The method is mild in condition and simple and convenient to operate, is suitablefor cracking aryl alkyl ether containing o-hydroxyl and o-carbonyl and acetal ether, and can also be used for removing tertiary carbon hydroxyl protecting groups with higher steric hindrance, such astriphenylmethyl, tertiary butyl and the like.
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Paragraph 0041-0057
(2020/09/16)
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- Reversible Covalent End-Capping of Collagen Model Peptides
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The combination of supramolecular aggregation of collagen model peptides with reversible covalent end-capping of the formed triple helix in a single experimental set-up yielded minicollagens, which were characterized by a single melting temperature. In spite of the numerous possible reaction intermediates, a specific synthetic collagen with a leading, middle and trailing strand is formed in a highly cooperative self-assembly process.
- Priem, Christoph,Geyer, Armin
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supporting information
p. 14278 - 14283
(2019/11/03)
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- Cell-Penetrating Dynamic-Covalent Benzopolysulfane Networks
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Cyclic oligochalcogenides (COCs) are emerging as promising systems to penetrate cells. Clearly better than and different to the reported diselenolanes and epidithiodiketopiperazines, we introduce the benzopolysulfanes (BPS), which show efficient delivery, insensitivity to inhibitors of endocytosis, and compatibility with substrates as large as proteins. This high activity coincides with high reactivity, selectively toward thiols, exceeding exchange rates of disulfides under tension. The result is a dynamic-covalent network of extreme sulfur species, including cyclic oligomers, from dimers to heptamers, with up to nineteen sulfurs in the ring. Selection from this unfolding adaptive network then yields the reactivities and selectivities needed to access new uptake pathways. Contrary to other COCs, BPS show high retention on thiol affinity columns. The identification of new modes of cell penetration is important because they promise new solutions to challenges in delivery and beyond.
- Cheng, Yangyang,Zong, Lili,López-Andarias, Javier,Bartolami, Eline,Okamoto, Yasunori,Ward, Thomas R.,Sakai, Naomi,Matile, Stefan
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supporting information
p. 9522 - 9526
(2019/06/24)
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- Dearomatization of Electron-Deficient Phenols to ortho-Quinones: Bidentate Nitrogen-Ligated Iodine(V) Reagents
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Despite their broad utility, the synthesis of ortho-quinones remains a significant challenge, in particular, access to electron-deficient derivatives remains an unsolved problem. Reported here is the first general method for the synthesis of electron-deficient ortho-quinones by direct oxidation of phenols. The reaction is enabled by a novel bidentate nitrogen-ligated iodine(V) reagent, a previously unexplored class of compounds which we have termed Bi(N)-HVIs. The reaction is extremely general and proceeds with excellent regioselectivity for the ortho over para isomer. Functionalization of the ortho-quinone products was examined, resulting in a facile one-pot synthesis of catechols, as well as the incorporation of a variety of heteroatom nucleophiles. This method represents the first synthetic application of Bi(N)-HVIs and demonstrates their potential as a platform for the further development of highly reactive, but also highly tunable, I(V) reagents.
- Xiao, Xiao,Greenwood, Nathaniel S.,Wengryniuk, Sarah E.
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p. 16181 - 16187
(2019/11/05)
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- Characterization and Crystal Structure of a Novel Mononuclear Cobalt(II) Complex with Hydrazone Derived from Protocatechuic Acid
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A novel complex [CoII(L)2·CH3OH] with hydrazone derived from protocatechuic acid (HL=C16H14N2O4) is designed and synthesized. The complex is characterized by single crystal X-ray
- Sheng,Wang,Feng,Gao,Zhu
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p. 140 - 144
(2018/03/23)
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- METHOD FOR PREPARING DIPHENYLMETHANE DERIVATIVES
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The present invention relates to an improved process for preparing a diphenyl methane derivative which is useful as an inhibitor of a sodium-dependent glucose transporter (SGLT). Since the process of the present invention is performed by convergent synthe
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Paragraph 0240; 0244; 0245
(2017/09/29)
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- Discovery of a series of 1,3,4-oxadiazole-2(3H)-thione derivatives containing piperazine skeleton as potential FAK inhibitors
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Focal adhesion kinase (FAK) is an important drug target that plays a fundamental role in mediating signal transduction system. We report herein the discovery of a novel class of 1,3,4-oxadiazole-2(3H)-thione derivatives containing piperazine skeleton with
- Sun, Juan,Ren, Shen-Zhen,Lu, Xiao-Yuan,Li, Jing-Jing,Shen, Fa-Qian,Xu, Chen,Zhu, Hai-Liang
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p. 2593 - 2600
(2017/04/04)
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- Ether bond breakage method for phenylalkyl ethers
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The invention discloses an ether bond breakage method for phenylalkyl ethers. The method comprises the step: subjecting the phenylalkyl ethers to an ether bond breakage reaction at the temperature of -20 DEG C to reflux temperature in an organic solvent in the presence of aluminum triiodide and carbodiimide, so as to produce phenols and derivatives thereof. The method is moderate in conditions, simple and convenient in operation, high in yield and wide in applicable phenylalkyl ether range.
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Paragraph 0125-0127
(2017/07/19)
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- Carbodiimides as Acid Scavengers in Aluminum Triiodide Induced Cleavage of Alkyl Aryl Ethers
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A practical procedure for the cleavage of alkyl aryl ethers containing labile functional groups has been developed using aluminum triiodide as the ether cleaving reagent. Carbodiimides, typically used as dehydration reagents for the coupling of amines and carboxylic acids to yield amide bonds, are found to be effective hydrogen iodide scavengers that prevent acid-labile groups from deterioration. The method is applicable to variant alkyl aryl ethers such as eugenol, vanillin, ortho -vanillin and methyl eugenol. Suitable substrates are not limited to alkyl o -hydroxyphenyl ethers.
- Sang, Dayong,Wang, Jiahui,Zheng, Yun,He, Jianyuan,Yuan, Caili,An, Qing,Tian, Juan
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p. 2721 - 2726
(2017/06/13)
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- Dendrimers with the protocatechuic acid building block for anticancer drug delivery
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Protocatechuic acid (3,4-dihydroxybenzoic acid; PCA) is a well-known antioxidant compound and a potential antitumor drug that is commonly found in fruits and vegetables. This article describes the development of novel biodegradable dendrimers that contain
- Xi, Xiujuan,Hu, Shiqi,Zhou, Zhuxian,Liu, Xiangrui,Tang, Jianbin,Shen, Youqing
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p. 5236 - 5245
(2016/08/17)
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- DICARBOXYLIC ACID COMPOUND AND DICARBOXYLIC ACID ESTER COMPOUND
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PROBLEM TO BE SOLVED: To provide a novel aromatic dicarboxylic acid derivative to serve as a raw material for heat resistant resin having excellent heat resistance and moldability, and a method for producing the same. SOLUTION: The present invention provi
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Paragraph 0030
(2016/10/17)
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- Antioxidant activity of protocatechuates evaluated by DPPH, ORAC, and CAT methods
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Hibiscus sabdariffa L. is a worldwide consumed plant, principally after infusion of its dried sepals and calyces, which are usually discarded. Nevertheless, they represent a potential source of natural bioactive compounds, e.g. polyphenols, which could ad
- Grajeda-Iglesias, Claudia,Salas, Erika,Barouh, Nathalie,Baréa, Bruno,Panya, Atikorn,Figueroa-Espinoza, Maria Cruz
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p. 749 - 757
(2015/09/07)
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- Synthesis, structure, and urease inhibitory activities of Co(III), Mn(II) and Zn(II) complexes with hydrazone derived from protocatechuic acid
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[CoIII(L1)2·H2O]NO3 (1), [MnII(L1)2·H2O] (2), and [ZnII(L1)2·H2O] (3) with a hydrazone derived from protocatechu
- Wang, Cun-Fang,Chen, Zhi-Jian,Zhao, Ke-Dong,Chen, Xiang-Fei,Zhang, Chun-Yang,Sheng, Gui-Hua,Zhu, Hai-Liang
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p. 2656 - 2665
(2016/09/13)
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- Oxadiazole-containing piperazine derivative as well as preparation method and use thereof
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The invention belongs to the technical field of organic synthesis, and particularly relates to an oxadiazole-containing piperazine derivative as well as a preparation method and use thereof. The oxadiazole-containing piperazine derivative provided by the
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Paragraph 0031; 0032
(2016/10/10)
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- Bismuth trichloride–mediated cleavage of phenolic methoxymethyl ethers
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A simple and efficient method for removal of phenolic methoxymethyl ethers in the presence of 30?mol% of bismuth trichloride in acetonitrile/water is described. Notable features of the cleavage protocol entail use of an ecofriendly bismuth reagent, ease of handling, low cost, operational simplicity, and good functional group compatibility. A number of structurally varied phenolic methoxymethyl ethers were cleaved in good to excellent yields.
- Obaro-Best, Oghale,Reed, Jack,Norfadilah, Alya A. F. B.,Monahan, Ryan,Sunasee, Rajesh
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supporting information
p. 586 - 593
(2016/06/08)
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- Divergent and concise total syntheses of dihydrochalcones and 5-deoxyflavones recently isolated from Tacca species and Mimosa diplotricha
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Dihydrochalcones and 5-deoxyflavones are types of compounds possessing various biologically interesting properties. Herein, we report the concise and divergent total syntheses of several naturally occurring dihydrochalcones and 5-deoxyflavones from readily available starting materials. The divergent strategy is based around manipulation of a common chalcone scaffold and features application of Algar-Flynn-Oyamada oxidation and benzoquinone C-H activation methodologies. These are the first reported total syntheses of these biologically interesting compounds and the concise and flexible route should be readily amenable to future analogue generation. Furthermore, this work provides an illustration of the utility of divergent synthesis for the expedient and step-economical preparation of natural product libraries.
- Sum, Tze Han,Sum, Tze Jing,Stokes, Jamie E.,Galloway, Warren R.J.D.,Spring, David R.
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p. 4557 - 4564
(2015/06/08)
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- Efficient Biomimetic Hydroxylation Catalysis with a Bis(pyrazolyl)imidazolylmethane Copper Peroxide Complex
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Bis(pyrazolyl)methane ligands are excellent components of model complexes used to investigate the activity of the enzyme tyrosinase. Combining the N donors 3-tert-butylpyrazole and 1-methylimidazole results in a ligand that is capable of stabilising a (μ-η2:η2)-dicopper(II) core that resembles the active centre of tyrosinase. UV/Vis spectroscopy shows blueshifted UV bands in comparison to other known peroxo complexes, due to donor competition from different ligand substituents. This effect was investigated with the help of theoretical calculations, including DFT and natural transition orbital analysis. The peroxo complex acts as a catalyst capable of hydroxylating a variety of phenols by using oxygen. Catalytic conversion with the non-biological phenolic substrate 8-hydroxyquinoline resulted in remarkable turnover numbers. In stoichiometric reactions, substrate-binding kinetics was observed and the intrinsic hydroxylation constant, kox, was determined for five phenolates. It was found to be the fastest hydroxylation model system determined so far, reaching almost biological activity. Furthermore, Hammett analysis proved the electrophilic character of the reaction. This sheds light on the subtle role of donor strength and its influence on hydroxylation activity.
- Wilfer, Claudia,Liebh?user, Patricia,Hoffmann, Alexander,Erdmann, Hannes,Grossmann, Oleg,Runtsch, Leander,Paffenholz, Eva,Schepper, Rahel,Dick, Regina,Bauer, Matthias,Dürr, Maximilian,Ivanovic-Burmazovic, Ivana,Herres-Pawlis, Sonja
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supporting information
p. 17639 - 17649
(2015/12/08)
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- Method for preparing protocatechuic acid lower alkyl ester from anthocyanins using irradiation
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The present invention relates to a method for preparing C1-C4 protocatechuic acid lower alkyl ester from anthocyanin using radiation and, more specifically to a method for preparing C1-C4 protocatechuic acid lower alkyl ester with radical removal capacity by irradiating an anthocyanin solution dissolved in C1-C4 lower alcohol with radiation. According to a method of the present invention, pigments are removed from anthocyanin by the degradation reaction of anthocyanin without a complex pigment removal process by using a radiation irradiating technology, and at the same time, C1-C4 protocatechuic acid lower alkyl ester with removal capacity for reactive oxygen species is generated, thereby maintaining anti-oxidant activity similarly as before irradiating radiation. Thus, the C1-C4 protocatechuic acid lower alkyl ester prepared by the present invention can be usefully used in foods, medicines and cosmetics as an active ingredient.COPYRIGHT KIPO 2015
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Paragraph 0072-0073
(2016/12/22)
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- Ring Opening of Bicyclo[3.1.0]hexan-2-ones: A Versatile Synthetic Platform for the Construction of Substituted Benzoates
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Described is the development of a highly efficient 2πdisrotatory ring-opening aromatization sequence using bicyclo[3.1.0]hexan-2-ones. This unprecedented transformation efficiently proceeds under thermal conditions and allows facile construction of uniquely substituted and polyfunctionalized benzoates. In the presence of either amines or alcohols formation of substituted anilines or ethers, respectively, is achieved. Additionally, the utility of this method was demonstrated in a short synthesis of sekikaic acid methyl ester. Cracked open: A highly efficient thermal 2πdisrotatory ring-opening aromatization sequence of bicyclo[3.1.0]hexan-2-ones is described. The transformation proceeds in sulfolane to give uniquely substituted benzoates. In the presence of either amines or alcohols, formation of substituted anilines or ethers, respectively, is achieved.
- Feierfeil, Johannes,Grossmann, Adriana,Magauer, Thomas
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supporting information
p. 11835 - 11838
(2015/10/05)
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- Design, synthesis and biological evaluation of small molecular polyphenols as entry inhibitors against H5N1
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To find novel compounds against H5N1, three series of known or novel small molecular polyphenols were synthesized and tested in vitro for anti-H5N1 activity. In addition, the preliminary structure-antiviral activity relationships were elaborated. The results showed that some small molecular polyphenols had better anti-H5N1 activity, and could serve as novel virus entry inhibitors against H 5N1, likely targeting to HA2 protein. Noticeably, compound 4a showed the strongest activity against H5N1 among these compounds, and the molecular modeling analysis also suggested that this compound might target to HA2 protein. Therefore, compound 4a is well qualified to serve as a lead compound or scaffold for the further development of H 5N1 entry inhibitor.
- Yang, Jian,Yang, Jing Xiang,Zhang, Fang,Chen, Gang,Pan, Wei,Yu, Rui,Wu, Shuwen,Tien, Po
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p. 2680 - 2684
(2014/06/09)
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- Aromatic diacylhydrazine derivatives as a new class of polo-like kinase 1 (PLK1) inhibitors
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A novel class of aromatic diacylhydrazine derivatives was designed as PLK1 inhibitors. All the 19 new synthesized compounds were assayed for antitumor activity against the respective cervical cancer cells. In which, nine compounds with better antitumor activities were further tested for their PLK1 inhibitory activity. Last, we have successfully found that compound 7k showed both the promising antitumor activity with IC50 of 0.17 μM against the cervical cancer cells, and also processed the most potent PLK1 inhibitory activity with IC50 of 0.03 μM. In addition, docking simulation also carried out in this study to give a potent prediction binding mode between the small molecule and PKL1 (PDB code: 1umw) protein.
- Sun, Juan,Lv, Peng-Cheng,Guo, Feng-Jiao,Wang, Xin-Yi,Han, Xiao-,Zhang, Yang,Sheng, Gui-Hua,Qian, Shao-Song,Zhu, Hai-Liang
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p. 420 - 426
(2014/06/09)
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- Synthesis, structure, and urease inhibitory activities of three binuclear copper(II) complexes with protocatechuic acid derivative
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Three Cu(II) complexes, [CuII2(L1) 4(L2)2] (1), [CuII 2(L1)4(H2O)2]·HL (2), and [CuII2(L1)
- Sheng, Gui-Hua,Zhou, Quan-Cheng,Sun, Juan,Cheng, Xiao-Shan,Qian, Shao-Song,Zhang, Chun-Yang,You, Zhong-Lu,Zhu, Hai-Liang
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p. 1265 - 1278
(2014/06/10)
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- Synthetic studies of fisetin, myricetin and nobiletin analogs and related probe molecules
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We synthesized a series of analogs of fisetin, myricetin and nobiletin, as well as related fluorescein- and biotin-based flavone-probe molecules, on a suitable scale for biological and structure-activity relationship studies.
- Hiza, Aiki,Tsukaguchi, Yuta,Ogawa, Takahiro,Inai, Makoto,Asakawa, Tomohiro,Hamashima, Yoshitaka,Kan, Toshiyuki
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p. 1371 - 1396
(2016/10/12)
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- Circumambulatory movement of negative charge ("ring walk") during gas-phase dissociation of 2,3,4-trimethoxybenzoate anion
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A dramatic "ortho effect" was observed during gas-phase dissociation of ortho-, meta-, and para-methoxybenzoate anions. Upon activation under mass spectrometric collisional activation conditions, anions generated from all three isomers undergo a CO2 loss. Of the m/z 107 ions generated in this way, only the 1-dehydro-2-methoxybenzene anion from the ortho isomer underwent an exclusive formaldehyde loss. A peak for a formaldehyde loss in the spectra of 2,4-, 2,5-, and 2,6-dimethoxybenzoates and the absence of an analogous peak from 3,4- and 3,5-dimethoxy derivatives confirmed that this is a diagnostically useful ortho-isomer-specific phenomenon. Moreover, the spectrum from 2,3-dimethoxybenzoic acid showed peaks for two consecutive formaldehyde losses. The 1-dehydro-2,3,4-trimethoxybenzene anion (m/z 167) generated from 2,3,4-trimethoxybenzoate in this way endures three consecutive eliminations of formaldehyde units. For this, the negative charge, initially located on position 1, circumambulates to position 2, then to position 3, and finally to position 4 to form the final phenyl anion. The proposed stepwise fragmentation pathway, which resembles the well-known E1cB-elimination mechanism, is supported by tandem mass spectrometric observations made with 2-[13C 2H3]methoxy-3-[13C]methoxy-4-methoxybenzoic acid, and ab initio calculations. In addition, the spectra of ions such as 1-dehydro-3,4-dimethoxybenzene anion show peaks for consecutive methyl radical losses, a feature that establishes the 1,2-relationship between the two methoxy groups.
- Herath, Kithsiri B.,Weisbecker, Carl S.,Singh, Sheo B.,Attygalle, Athula B.
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p. 4378 - 4389
(2014/06/09)
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- Bio-inspired synthesis of rare and unnatural carbohydrates and cyclitols through strain driven epimerization
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We report a bio-inspired, strain driven epimerization of trans-ketals to cis-ketals through an enolate intermediate. Swern oxidation of a hydroxyl group adjacent to a trans-ketal effects both oxidation and its epimerization to cis-ketal. This novel and general strategy allows inversion of up to three contiguous stereocenters and has been illustrated by the synthesis of several unnatural/rare isomers of carbohydrates/cyclitols from their naturally abundant isomers. This journal is the Partner Organisations 2014.
- Mohanrao, Raja,Asokan, Aromal,Sureshan, Kana M.
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supporting information
p. 6707 - 6710
(2014/06/23)
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- Mono-/dihydroxybenzoic acid esters and phenol pyridinium derivatives as inhibitors of the mammalian carbonic anhydrase isoforms I, II, VII, IX, XII and XIV
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Using hydroxy-/dihydroxybenzoic acids as leads, a series of methyl, ethyl and iso-propyl esters of 4-hydroxy-benzoic acid, 2,4-, 2,5-, 2,6-, 3,4-, and 3,5-dihydroxybenzoic acids and of coumaric acid, were obtained and investigated for the inhibition of six mammalian carbonic anhydrase (CA, EC 4.2.1.1) isoforms, that is, the cytosolic CA I, II and VII, and the transmembrane CA IX, XII and XIV, many of which are established drug targets. Other compounds incorporating phenol/catechol moieties were obtained from dopamine by reaction with fluorescein isothiocyanate or with 2,4,6-trisubstituted pyrylium salts. Some aminophenols were also derivatized in a similar manner, by using pyrylium salts. Many of these compounds showed increased inhibitory action compared to the lead compounds from which they were obtained, with efficacy in the submicromolar range against most investigated CA isoforms. As phenols are a class of less investigated CA inhibitors (CAIs) compared to the sulfonamides, and their mechanism of inhibition is less well understood, compounds of the type designed here may be helpful in gaining more insights into these phenomena.
- Carta, Fabrizio,Vullo, Daniela,Maresca, Alfonso,Scozzafava, Andrea,Supuran, Claudiu T.
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supporting information
p. 1564 - 1569
(2013/04/10)
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- Synthesis and antitumor activity of 1,3,4-oxadiazole possessing 1,4-benzodioxan moiety as a novel class of potent methionine aminopeptidase type II inhibitors
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A series of 1,3,4-oxadiazole derivatives containing 1,4-benzodioxan moiety (7a-7q) have been designed, synthesized and evaluated for their antitumor activity. Most of the synthesized compounds were proved to have potent antitumor activity and low toxicity. Among them, compound 7a showed the most potent biological activity against Human Umbilical Vein Endothelial cells, which was comparable to the positive control. The results of apoptosis and flow cytometry (FCM) demonstrated that compound 7a induce cell apoptosis by the inhibition of MetAP2 pathway. Molecular docking was performed to position compound 7a into MetAP2 binding site in order to explore the potential target.
- Sun, Juan,Li, Ming-Hui,Qian, Shao-Song,Guo, Feng-Jiao,Dang, Xiao-Fang,Wang, Xiao-Ming,Xue, Ya-Rong,Zhu, Hai-Liang
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supporting information
p. 2876 - 2879
(2013/06/26)
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- Modular synthesis of amphiphilic Janus glycodendrimers and their self-assembly into glycodendrimersomes and other complex architectures with bioactivity to biomedically relevant lectins
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The modular synthesis of 7 libraries containing 51 self-assembling amphiphilic Janus dendrimers with the monosaccharides d-mannose and d-galactose and the disaccharide d-lactose in their hydrophilic part is reported. These unprecedented sugar-containing dendrimers are named amphiphilic Janus glycodendrimers. Their self-assembly by simple injection of THF or ethanol solution into water or buffer and by hydration was analyzed by a combination of methods including dynamic light scattering, confocal microscopy, cryogenic transmission electron microscopy, Fourier transform analysis, and micropipet-aspiration experiments to assess mechanical properties. These libraries revealed a diversity of hard and soft assemblies, including unilamellar spherical, polygonal, and tubular vesicles denoted glycodendrimersomes, aggregates of Janus glycodendrimers and rodlike micelles named glycodendrimer aggregates and glycodendrimermicelles, cubosomes denoted glycodendrimercubosomes, and solid lamellae. These assemblies are stable over time in water and in buffer, exhibit narrow molecular-weight distribution, and display dimensions that are programmable by the concentration of the solution from which they are injected. This study elaborated the molecular principles leading to single-type soft glycodendrimersomes assembled from amphiphilic Janus glycodendrimers. The multivalency of glycodendrimersomes with different sizes and their ligand bioactivity were demonstrated by selective agglutination with a diversity of sugar-binding protein receptors such as the plant lectins concanavalin A and the highly toxic mistletoe Viscum album L. agglutinin, the bacterial lectin PA-IL from Pseudomonas aeruginosa, and, of special biomedical relevance, human adhesion/growth-regulatory galectin-3 and galectin-4. These results demonstrated the candidacy of glycodendrimersomes as new mimics of biological membranes with programmable glycan ligand presentations, as supramolecular lectin blockers, vaccines, and targeted delivery devices.
- Percec, Virgil,Leowanawat, Pawaret,Sun, Hao-Jan,Kulikov, Oleg,Nusbaum, Christopher D.,Tran, Tam M.,Bertin, Annabelle,Wilson, Daniela A.,Peterca, Mihai,Zhang, Shaodong,Kamat, Neha P.,Vargo, Kevin,Moock, Diana,Johnston, Eric D.,Hammer, Daniel A.,Pochan, Darrin J.,Chen, Yingchao,Chabre, Yoann M.,Shiao, Tze C.,Bergeron-Brlek, Milan,Andre, Sabine,Roy, Rene,Gabius, Hans-J.,Heiney, Paul A.
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supporting information
p. 9055 - 9077
(2013/07/26)
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- Synergistic effect of additives on cyclopropanation of olefins
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An efficient cyclopropanation of olefins with Zn(CH2I) 2, a catalytic amount of CCl3CO2H, and 1,2-dimethoxyethane at room temperature is described. A wide variety of olefins, including acid-sensitive substrates,
- Cheng, Donghao,Huang, Deshun,Shi, Yian
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supporting information
p. 5588 - 5591
(2013/09/12)
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- Catalytic phenol hydroxylation with dioxygen: Extension of the tyrosinase mechanism beyond the protein matrix
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A new catalyst (see structure) hydroxylates phenols with O2 via a stable side-on peroxide complex, which is similar to the active site of tyrosinase in terms of the ligand environment and its spectroscopic properties. The catalytic oxidation of phenols to quinones proceeds at room temperature in the presence of NEt3 and even non-native substrates can be oxidized catalytically. The reaction mechanism is analogous to that of the enzyme-catalyzed reaction. Copyright
- Hoffmann, Alexander,Citek, Cooper,Binder, Stephan,Goos, Arne,Ruebhausen, Michael,Troeppner, Oliver,Ivanovic-Burmazovic, Ivana,Wasinger, Erik C.,Stack, T. Daniel P.,Herres-Pawlis, Sonja
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supporting information
p. 5398 - 5401
(2013/06/27)
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- Efficient synthesis of the siderophore petrobactin via antimony triethoxide mediated coupling
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Chemical synthesis of petrobactin, a siderophore for Bacillus anthracis, has been achieved via Sb(OEt)3-mediated ester-amide exchange.
- Pandey, Rajesh K.,Jarvis, Gregory G.,Low, Philip S.
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scheme or table
p. 1627 - 1629
(2012/04/17)
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- Identification of glycogen synthase kinase-3 inhibitors with a selective sting for glycogen synthase kinase-α
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The glycogen synthase kinase-3 (GSK-3) has been linked to the pathogenesis of colorectal cancer, diabetes, cardiovascular disease, acute myeloid leukemia (AML), and Alzheimer's disease (AD). The debate on the respective contributions of GSK-α and GSK-3β to AD pathology and AML is ongoing. Thus, the identification of potent GSK-α-selective inhibitors, endowed with favorable pharmacokinetic properties, may elucidate the effect of GSK-α inhibition in AD and AML models. The analysis of all available crystallized GSK-3 structures provided a simplified scheme of the relevant hot spots responsible for ligand binding and potency. This resulted in the identification of novel scorpion shaped GSK-3 inhibitors. It is noteworthy, compounds 14d and 15b showed the highest GSK-α selectivity reported so far. In addition, compound 14d did not display significant inhibition of 48 out of 50 kinases in the test panel. The GSK-3 inhibitors were further profiled for efficacy and toxicity in the wild-type (wt) zebrafish embryo assay.
- Lo Monte, Fabio,Kramer, Thomas,Gu, Jiamin,Anumala, Upendra Rao,Marinelli, Luciana,La Pietra, Valeria,Novellino, Ettore,Franco, Bénédicte,Demedts, David,Van Leuven, Fred,Fuertes, Ana,Dominguez, Juan Manuel,Plotkin, Batya,Eldar-Finkelman, Hagit,Schmidt, Boris
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experimental part
p. 4407 - 4424
(2012/08/13)
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- Chemical interaction between polyphenols and a cysteinyl thiol under radical oxidation conditions
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Chemical interaction between polyphenols and thiols was investigated under radical oxidation conditions using a model cysteinyl thiol derivative, N-benzoylcysteine methyl ester. The radical oxidation was carried out with a stoichiometric amount of 2,2-diphenyl-1-picrylhydrazyl (DPPH), and the decreases in the amounts of polyphenols and the thiol were measured by HPLC analysis. Cross-coupling products between various polyphenols and the thiol were examined by LC-MS in reactions that showed decreases in both the polyphenols and the thiol. The LC-MS results indicated that three phenolic acid esters (methyl caffeate, methyl dihydrocaffeate, and methyl protocatechuate) and six flavonoids (kaempferol, myricetin, luteolin, morin, taxifolin, and catechin) gave corresponding thiol adducts, whereas three polyphenols (methyl ferulate, methyl sinapate, and quercetin) gave only dimers or simple oxidation products without thiol substituents. Thiol adducts of the structurally related compounds methyl caffeate and methyl dihydrocaffeate were isolated, and their chemical structures were determined by NMR analysis. The mechanism for the thiol addition was discussed on the basis of the structures of the products.
- Fujimoto, Aya,Masuda, Toshiya
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experimental part
p. 5142 - 5151
(2012/10/07)
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- Alkyl hydroxybenzoic acid derivatives that inhibit HIV-1 protease dimerization
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The therapeutic potential of gallic acid and its derivatives as anti-cancer, antimicrobial and antiviral agents is well known. We have examined the mechanism by which natural gallic acid and newly synthesized gallic acid alkyl esters and related protocatechuic acid alkyl esters inhibit HIV-1 protease to compare the influence of the aromatic ring substitutions on inhibition. We used Zhang-Poorman's kinetic analysis and fluorescent probe binding to demonstrate that several gallic and protecatechuic acid alkyl esters inhibited HIV-1 protease by preventing the dimerization of this obligate homodimeric aspartic protease rather than targeting the active site. The tri-hydroxy substituted benzoic moiety in gallates was more favorable than the di-substituted one in protocatechuates. In both series, the type of inhibition, its mechanism and the inhibitory efficiency dramatically depended on the length of the alkyl chain: no inhibition with alkyl chains less than 8 carbon atoms long. Molecular dynamics simulations corroborated the kinetic data and propose that gallic esters are intercalated between the two N- and C-monomer ends. They complete the β-sheet and disrupt the dimeric enzyme. The best gallic ester (14 carbon atoms, Kid of 320 nM) also inhibited the multi-mutated protease MDR-HM. These results will aid the rational design of future generations of non-peptide inhibitors of HIV-1 protease dimerization that inhibit multi-mutated proteases. Finally, our work suggests the wide use of gallic and protocatechuic alkyl esters to dissociate intermolecular β-sheets involved in protein-protein interactions.
- Flausino Jr., O. A.,Dufau, L.,Reboud-Ravaux, M.,Regasini, L. O.,Petronio, M. S.,Silva, D. H. S.,Bolzani, V. S.,Rose, T.
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p. 4534 - 4540,7
(2012/12/12)
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- A new family of bent-core C2-symmetric liquid crystals
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A series of C2-symmetric compounds with different core sizes and varying lengths and numbers of alkoxy side chains were prepared, and the factors influencing their liquid crystalline mesophase behaviour were investigated. The compounds studied were based on benzophenone, dibenzylidene-acetone, and 1,9-diphenyl-nona-1,3,6,8-tetraen-5-one cores with either 1 or 2 linear alkoxy side chains. The side chains were varied in length from C6H13 to C12H25. The liquid crystalline mesophase behaviour of the compounds was investigated using differential scanning calorimetry, polarizing optical microscopy, and small-angle X-ray scattering (SAXS). It was found that a number of the molecules were able to self-assemble into smectic and nematic liquid crystalline phases.
- Hope-Ross, Kyle A.,Heiney, Paul A.,Kadla, John F.
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supporting information; experimental part
p. 639 - 645
(2010/08/21)
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