- Synthesis and Insect Growth Regulatory Activity of Alkoxy-Substituted Benzaldoxime Ethers
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Alkoxy-substituted benzaldoxime ethers, namely (i) 3-methoxy-4-ethoxybenzaldoxime N-O-alkyl ethers, (ii) 3,4-dimethoxybenzaldoxime N-O-alkyl ethers, and (iii) 3,4-methylenedioxybenzaldoxime N-O-alkyl ethers, have been synthesized and evaluated for their insect growth regulatory activity against fifth-instar nymphs of the desert locust Schistocerca gregaria F. When injected into insect hemolymph at the lowest dose level of 3 μg/nymph, 3,4-methylenedioxybenzaldoxime N-O-methyl ether and 3,4-methylenedioxybenzaldoxime N-O-isopropyl ether showed 40 and 50% growth deformities respectively. On topical application (at 20 μg/nymph) 3-methoxy-4-ethoxybenzaldoxime N-O-methyl ether inflicted 100% abnormalties in insect growth. Structure-activity relationship studies revealed that maximum activity was associated with compounds having three carbons in the oxime ether moiety.
- Chowdhury,Saxena,Walia
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- Synthesis and characterization of new homologous series of unsymmetrical liquid crystalline compounds based on chalcones and 3, 5-disubstituted isoxazoles
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Two homologous series of unsymmetrical alkylated chalcones and 3,5-diaryl isoxazoles, consisting of 20 members, with various n-alkyl bromides (n=2?7, 10, 12, 14, 16) have been synthesized and studied for their liquid crystalline property. Simple strategy was employed to achieve the target materials. Flexibility in the synthesized molecules is provided by attaching straight alkoxy chains, where one terminal group is fixed and other terminal group is varied. The synthesized compounds were characterized on the basis of Mass, IR and NMR spectroscopy. The stability and the range of the mesophases increased with the length of the chain on the isoxazoles. The melting point, transition temperatures and enantiotropic liquid crystal morphologies were determined by polarizing optical microscopy (POM) in conjunction with a hot stage and by differential scanning calorimetry (DSC). [Figure not available: see fulltext.]
- Sowmya,Lokanatha Rai
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- Synthesis, crystal structure, experimental and theoretical investigations of 3-(4-ethoxy-3-methoxyphenyl)-1-phenylprop-2-en-1-one
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A chalcone derivative namely, (E)-3-(4-ethoxy-3-methoxyphenyl)-1-phenylprop-2-en-1-one (1v) has been synthesized and characterized on the basis of its spectral data. The solid state self-assembly studies of 1v were carried out through single crystal X-ray technique to see the major non-covalent interactions responsible for molecular alignment in the solid state. Furthermore, the optimized molecular geometry, vibrational frequencies, 1H and 13C NMR chemical shift (in gas and in chloroform solvent) values and the molecular electrostatic potential (MEP) surface parameters of 1v were calculated using DFT/B3LYP/HF/M06 method with 6–311++G (d,p) basis set in ground state. All the theoretical calculations for 1v were found in good agreement with experimental data.
- Anam, Faiza,Abbas, Asghar,Lo, Kong Mun,Hameed, Shahid,Ramasami, Ponnadurai,Umar, Yunusa,Ullah, Aman,Naseer, Muhammad Moazzam
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- COMPOUNDS, COMPOSITIONS AND METHODS FOR TREATING NASH, NAFLD, AND OBESITY
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The present technology relates to methods of treating NASH, NAFLD and/or obesity using compounds of Formulas I, II, III, IV, V, and/or VI. The methods include administering to a subject suffering from one or more of non-alcoholic steatohepatitis (NASH), non- alcoholic fatty liver disease (NAFLD) and/or obesity a therapeutically effective amount of such a compound
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Paragraph 00285
(2021/04/10)
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- Transaminase-mediated synthesis of enantiopure drug-like 1-(3′,4′-disubstituted phenyl)propan-2-amines
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Transaminases (TAs) offer an environmentally and economically attractive method for the direct synthesis of pharmaceutically relevant disubstituted 1-phenylpropan-2-amine derivatives starting from prochiral ketones. In this work, we report the application of immobilised whole-cell biocatalysts with (R)-transaminase activity for the synthesis of novel disubstituted 1-phenylpropan-2-amines. After optimisation of the asymmetric synthesis, the (R)-enantiomers could be produced with 88-89% conversion and >99% ee, while the (S)-enantiomers could be selectively obtained as the unreacted fraction of the corresponding racemic amines in kinetic resolution with >48% conversion and >95% ee. This journal is
- Lakó, ágnes,Mendon?a, Ricardo,Molnár, Zsófia,Poppe, László
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p. 40894 - 40903
(2020/11/23)
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- Novel vanillin derivatives containing a 1,3,4-thiadiazole moiety as potential antibacterial agents
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In this study, thirty-four novel vanillin derivatives containing a 1,3,4-thiadiazole structure were obtained and their antibacterial activities were evaluated. The results indicate that most of the title compounds displayed inhibitory effects on Xanthomonas oryzae pv. oryzae (Xoo) and Xanthomonas oryzae pv. oryzicola (Xoc). Among them, compound 29 exhibited excellent antibacterial activities against Xoo and Xoc in vitro, with the EC50 values of 3.14 and 8.83 μg/mL, respectively, much superior to thiodiazole copper (87.03 and 108.99 μg/mL) and bismerthiazol (67.64 and 79.26 μg/mL). Under greenhouse condition, the protective efficiency of compound 29 against rice bacterial leaf blight was 49.34%, and curative efficiency was 40.96%. In addition, compound 29 can reduce the exopolysaccharides production of Xoo, increase the permeability of cell membrane and damage cell membrane.
- Cai, Hui,Gan, Xiuhai,Li, Shaoyuan,Song, Baoan,Wu, Qiong,Yuan, Ting
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supporting information
(2020/03/24)
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- First Discovery of Novel Pyrido[1,2- a]pyrimidinone Mesoionic Compounds as Antibacterial Agents
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Plant bacterial diseases cause tremendous decreases in crop yield and quality, and there is a lack of highly effective and low-risk antibacterial agents. A series of novel pyrido[1,2-a]pyrimidinone mesoionic compounds containing vanillin moieties were synthesized, and the application of these mesoionic compounds as plant antibacterial agents was reported here for the first time. The bioassay results revealed that the mesoionic compounds had good antibacterial activity. Of these compounds, compound 11 showed excellent in vitro activity against Xanthomonas oryzae pv. oryzae, with an EC50 value of 1.1 μg/mL, which was substantially better than that of bismerthiazol (92.7 μg/mL) and thiodiazole copper (105.4 μg/mL). Moreover, greenhouse condition trials indicated that the protective and curative activities of compound 11 against rice bacterial leaf blight were 75.12 and 72.04%, respectively, which were better than those of bismerthiazol (62.24 and 50.83%, respectively) and thiodiazole copper (53.35 and 65.04%, respectively). These results provide a basis for the application of mesoionic vanillin moieties as new antibacterial agents.
- Liu, Dengyue,Zhang, Jian,Zhao, Lei,He, Wengjing,Liu, Zhengjun,Gan, Xiuhai,Song, Baoan
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- 3-methyl pyridino-[1,2-a] pyrimidone derivative containing 1-((4-benzyl-substituted)oxygroup) and application
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The invention discloses a 3-methyl pyridino-[1,2-a] pyrimidone derivative containing 1-((4-benzyl-substituted)oxygroup) and application. The general formula of the derivative is shown in the description, wherein R1 is a methoxyl group or an oxyethyl group or halogen; R2 is hydroxyl or isobutyl or ethyl or propyl or chloroethyl or 2-methoxyl group benzyl or 2-methoxyl group benzy or 2-fluorine benzyl or 2-cyanogroup benzyl chloride or 4-cyanogroup benzyl2-methyl benzyl chloride or 3-methyl benzyl chloride or 4-methyl benzyl chloride. According to the derivative, the rice bacterial leaf blight and citrus canker can be prevented and treated. The general formula is shown in the description.
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Paragraph 0149; 0151
(2019/04/30)
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- Synthesis of N-Substituted Condensed Tetrahydropyridine-Based Enaminones via Palladium-Catalyzed Intramolecular C–N Cross-coupling
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A number of β-enaminones with secondary amino group (alkyl, cyclopropyl, and aryl) were prepared from corresponding β-diketones. Two general protocols for their palladium-catalyzed intramolecular C–N cross-coupling were established to give corresponding N-substituted condensed tetrahydropyridines in good yields. The methodology is applicable for a wide variety of structural motifs. The work also extends the applicability of novel, recently established, palladium precatalysts to new substrates.
- Dou?ová, Hana,R??i?ková, Zdeňka,?im?nek, Petr
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supporting information
p. 670 - 684
(2018/01/22)
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- Kinetics and DFT Studies of Photoredox Carbon-Carbon Bond Cleavage Reactions by Molecular Vanadium Catalysts under Ambient Conditions
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Visible light assisted photocatalytic organic reactions have recently received intense attention as a versatile approach to achieve selective chemical transformations, including C-C and several C-X (X = N, O, S) bond formations under mild reaction conditions. The light harvesters in previous reports predominantly comprise ruthenium or iridium photosensitizers. In contrast, selective, photocatalytic aliphatic C-C bond cleavage reactions are scarce. The present study focuses on rationally designing VV oxo complexes as molecular, photoredox catalysts toward the selective activation and cleavage of a C-C bond adjacent to the alcohol group in aliphatic alcoholic substrates. We have employed kinetics measurements and DFT calculations to develop a candidate for the catalytic C-C bond activation reaction that is up to 7 times faster than our original vanadium complex. We have also identified a substrate where the C-C bond cleaves at rates 2.5-17 times faster, depending on the catalyst used. In order to better understand the effects of ligand modification on the thermodynamics and catalysis, DFT calculations were employed to reveal the orbital energies, the electronic transitions during the C-C bond cleavage, and the activation barriers. Our combined kinetics and computational studies indicate that the incorporation of electron-withdrawing groups at select sites of the ligand is essential for the development of active and stable vanadium photocatalysts for our C-C bond cleavage reactions.
- Gazi, Sarifuddin,Doki?, Milo?,Moeljadi, Adhitya Mangala Putra,Ganguly, Rakesh,Hirao, Hajime,Soo, Han Sen
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p. 4682 - 4691
(2017/07/24)
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- SELECTIVE CARBON-CARBON BOND CLEAVAGE BY EARTH ABUNDANT VANADIUM COMPOUNDS UNDER VISIBLE LIGHT PHOTOCATALYSIS
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Provided herein a vanadium(V) complex of formula I, where R1 to R8 are as defined herein. Also provided herein are reactions making use of the vanadium(V) complex of formula I, such as selective sp3-sp3 carbon-carbon bond cleavage under visible light photocatalysis and photodegradation of lignin.
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Page/Page column 48
(2016/09/22)
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- Ferrocenyl chalcones with O-alkylated vanillins: synthesis, spectral characterization, microbiological evaluation, and single-crystal X-ray analysis
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O-alkylated vanillin derivatives 2a–f and acetylferrocene react under Claisen–Schmidt conditions, resulting in good-to-high yields of the corresponding ferrocene chalcones 3a–f. None of the resultant compounds 3b–f has been previously described in the literature. All synthesized compounds were characterized by spectral and physical data, whereas two of them, 1-ferrocenyl-3-(4-ethoxy-3-methoxyphenyl)-prop-2-en-1-one (3b) and 1-ferrocenyl-3-(4-buthoxy-3-methoxy-phenyl)-prop-2-en-1-one (3e), were crystalline substances, suitable for single-crystal X-ray analysis, which confirmed undoubtedly their structures. Chalcones 3a–f were tested for their biological activity and demonstrated relatively good in vitro antimicrobial activity towards different strains of bacteria and fungi. The best antibacterial activity is expressed by compounds 3b and 3c, while compound 3d shows the best antifungal activity.
- Mu?kinja, Jovana,Burmud?ija, Adrijana,Ratkovi?, Zoran,Rankovi?, Branislav,Kosani?, Marijana,Bogdanovi?, Goran A.,Novakovi?, Sla?ana B.
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p. 1744 - 1753
(2016/10/03)
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- Selective photocatalytic C-C bond cleavage under ambient conditions with earth abundant vanadium complexes
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Selective C-C bond cleavage under ambient conditions is a challenging chemical transformation that can be a valuable tool for organic syntheses and macromolecular disassembly. Herein, we show that base metal vanadium photocatalysts can harvest visible light to effect the chemoselective C-C bond cleavage of lignin model compounds under ambient conditions. Lignin, a major aromatic constituent of non-food biomass, is an inexpensive, accessible source of fine chemical feedstocks such as phenols and aryl ethers. However, existing lignin degradation technologies are harsh and indiscriminately degrade valuable functional groups to produce intractable mixtures. The selective, photocatalytic depolymerization of lignin remains underexplored. In the course of our studies on lignin model compounds, we have uncovered a new C-C activation reaction that takes place under exceptionally mild conditions with high conversions. We present our fundamental studies on representative lignin model compounds, with the aim of expanding and generalizing the substrate scope in the future. Visible light is employed in the presence of earth-abundant vanadium oxo catalysts under ambient conditions. Selective C-C bond cleavage leads to valuable and functionally rich fine chemicals such as substituted aryl aldehydes and formates. Isotope labeling experiments, product analyses, and intermediate radical trapping, together with density functional theory studies, suggest a unique pathway that involves a photogenerated T1 state during the C-C bond cleavage reactions. Our study demonstrates a sustainable approach to harvest sunlight for an unusual, selective bond activation, which can potentially be applied in organic transformations and biomass valorization.
- Gazi, Sarifuddin,Hung Ng, Wilson Kwok,Ganguly, Rakesh,Putra Moeljadi, Adhitya Mangala,Hirao, Hajime,Soo, Han Sen
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p. 7130 - 7142
(2015/11/24)
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- Design, synthesis and anti-proliferative effects in tumor cells of new combretastatin A-4 analogs
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Abstract A total of 11 novel combretastatin A-4 (CA-4) analogs were designed, synthesized, and evaluated for the anti-proliferative effects in tumor cells. The compounds represent four structural classes: (i) hydrogenated derivatives, (ii) ethoxyl derivatives, (iii) amino derivatives and (iv) pro-drugs. Biological evaluations demonstrate that multiple structural features control the biological potency. Three of the compounds, sit-1, sit-2 and sit-3, have potent anti-proliferative activity against multiple cancer cell lines. Their pro-drugs were synthesized to increase water solubility. Structure-activity relationship study and Surflex-Docking were studied in this paper. These results will be useful for the design of new CA-4 analogs that are structurally related to the SAR study.
- Zhao, Lei,Zhou, Jiu-Jiu,Huang, Xin-Ying,Cheng, Li-Ping,Pang, Wan,Kai, Zhen-Peng,Wu, Fan-Hong
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p. 993 - 999
(2015/08/19)
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- THIOPHENE DERIVATIVES
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Disclosed is a compound of formula (1), wherein R1, R2, R3, R4, R5, R6, R7 and R8 are as defined in the present application.
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Page/Page column 23
(2012/04/17)
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- Synthesis and biological evaluation of isosteric analogs of mandipropamid for the control of oomycete pathogens
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A series of isosteric analogs of mandipropamid were designed and synthesized via 'click chemistry'. The amide bond of mandipropamid was substituted by a 1,2,3-triazole functional group. The bioassay results have indicated that some of the title compounds exhibited moderate fungicidal activity against Pseudoperonospora cubensis, and the activity has been systematically studied as a function of molecular structure. The low activity of the mandipropamid analog that contains a lipid chain is likely due to the presence of a weak hydrogen bond donor in the 1,2,3-triazole. Furthermore, we have performed the molecular modeling and found that N-methylamide could be more effective than amide as the surrogates to 1,2,3-triazole, which ultimately leads to a longer distance (1.1A longer) between the two substitutes in the 1,4-disubstituted 1,2,3-triazole compound.
- Su, Na,Wang, Zhen-Jun,Wang, Li-Zhong,Zhang, Xiao,Dong, Wei-Li,Wang, Hong-Xue,Li, Zheng-Ming,Zhao, Wei-Guang
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scheme or table
p. 101 - 111
(2012/06/01)
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- Alkoxyl- and carbon-centered radicals as primary agents for degrading non-phenolic lignin-substructure model compounds
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Lignin degradation by white-rot fungi proceeds via free radical reaction catalyzed by oxidative enzymes and metabolites. Basidiomycetes called selective white-rot fungi degrade both phenolic and non-phenolic lignin substructures without penetration of extracellular enzymes into the cell wall. Extracellular lipid peroxidation has been proposed as a possible ligninolytic mechanism, and radical species degrading the recalcitrant non-phenolic lignin substructures have been discussed. Reactions between the non-phenolic lignin model compounds and radicals produced from azo compounds in air have previously been analysed, and peroxyl radical (PR) is postulated to be responsible for lignin degradation (Kapich et al., FEBS Lett., 1999, 461, 115-119). However, because the thermolysis of azo compounds in air generates both a carbon-centred radical (CR) and a peroxyl radical (PR), we re-examined the reactivity of the three radicals alkoxyl radical (AR), CR and PR towards non-phenolic monomeric and dimeric lignin model compounds. The dimeric lignin model compound is degraded by CR produced by reaction of 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH), which under N2 atmosphere cleaves the α-β bond in 1-(4-ethoxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol to yield 4-ethoxy-3-methoxybenzaldehyde. However, it is not degraded by the PR produced by reaction of Ce4+/tert-BuOOH. In addition, it is degraded by AR produced by reaction of Ti3+/tert-BuOOH. PR and AR are generated in the presence and absence of veratryl alcohol, respectively. Rapid-flow ESR analysis of the radical species demonstrates that AR but not PR reacts with the lignin model compound. Thus, AR and CR are primary agents for the degradation of non-phenolic lignin substructures.
- Ohashi, Yasunori,Uno, Yukiko,Amirta, Rudianto,Watanebe, Takahito,Honda, Yoichi,Watanabe, Takashi
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experimental part
p. 2481 - 2491
(2011/05/14)
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- ETHOXY DIPHENYL ETHANE DERIVATES, PREPARATION PROCESSES AND USES THEREOF
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The invention discloses an ethoxydiphenylethane derivative and a synthetic method and uses thereof 4' position of phenylethane B aromatic ring is chemically modified by ethoxy and hydroxy at position 3' thereof is simultaneously modified to water soluble prodrug such as phosphate, and similarly, amino acid side chain is introduced to amino at position 3' to form amino acid amide water soluble prodrug having the structure shown as formula (I) the ethoxydiphenylethane derivative and the prodrug thereof include strong tubulin aggregation inhibiting ability and obvious target damage effect for tumor vessels, selectively cause dysfunction and structural damage of tumor vessels and induce apoptosis of vascular endothelial cells in order to play the role of killing tumor cells or inhibiting tumor metastasis in case that the tumor cells are free from the support of nutrition and oxygen.
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Page/Page column 9
(2011/08/08)
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- Compounds and Compositions for Modulating Lipid Levels and Methods of Preparing Same
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The present technology relates to compounds of Formulas I-VI and methods of making and using such compounds. Methods of use include prevention and treatment of hyperlipidemia, hypercholesterolemia, hypertriglyceridemia, hepatic steatosis, and metabolic syndrome. Compounds disclosed herein also increase HDL-C, lower total cholesterol, LDL-cholesterol, and triglycerides and increase hepatic LDL receptor expression, inhibit PCSK9 expression, and activate AMP-activated protein kinase.
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Page/Page column 40-41
(2011/02/15)
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- S1P RECEPTORS MODULATORS
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The invention relates to novel compounds that have S1P receptor modulating activity and, preferably, apoptotic activity and/or anti proliferative activity against cancer cells and other cell types. Further, the invention relates to a pharmaceutical comprising at least one compound of the invention for the treatment of diseases and/or conditions caused by or associated with inappropriate S1P receptor modulating activity or expression, for example, cancer. A further aspect of the invention relates to the use of a pharmaceutical comprising at least one compound of the invention for the manufacture of a medicament for the treatment of diseases and/or conditions caused by or associated with inappropriate S1P receptor modulating activity or expression such as cancer.
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Page/Page column 125
(2010/04/30)
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- CORYDALINE DERIVATIVES USEFUL FOR REDUCING LIPID LEVELS
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The present technology relates to compounds of Formulas (V) and (VI) and methods of making and using such compounds. Methods of use include prevention and treatment of hyperlipidemia, hypercholesterolemia, hypertriglyceridemia, hepatic steatosis, and metabolic syndrome. Compounds disclosed herein also lower total cholesterol, LDL- cholesterol, and triglycerides and increase hepatic LDL receptor expression, inhibit PCSK9 expression, and activate AMP-activated potein kinase.
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Page/Page column 118
(2010/07/09)
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- THE PREPARTION AND THE USE OF ETHOXY COMBRETASTATINS AND THEIR PRODRUGS
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The invention disclosed a total synthesis process of novel ethoxy combretastatins and their prodrugs. Combretastatins are chemically modified by ethoxy substituted on the 4'-position of their B aryl ring and are converted to be their soluble prodrugs of phosphate or their inner salt of phosphorylcholine by modifying the hydroxyl on the 3'-position of their B aryl ring. Similarly, 3'-amino combretastatin is 4'-ethoxy chemically modified and further side chain of amino acid can be introduced to the amino to form soluble prodrug of amino acidamide. The structure of the said compound is showed as formula (I). Ethoxy combretastatins possess potent tubulin polymerization inhibitory activity and can be used for the treatment of inhibiting tumor or neovascular.
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Page/Page column 10-11; 19
(2009/06/27)
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- PREPARATION AND THE USE OF ETHOXY COMBRETASTATINS AND THEIR PRODRUGS
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The invention disclosed a total synthesis process of novel ethoxy combretastatins and their prodrugs. Combretastatins are chemically modified by ethoxy substituted on the 4′-position of their B aryl ring and are converted to be their soluble prodrugs of phosphate or their inner salt of phosphorylcholine by modifying the hydroxyl on the 3′-position of their B aryl ring. Similarly, 3′-amino combretastatin is 4′-ethoxy chemically modified and further side chain of amino acid can be introduced to the amino to form soluble prodrug of amino acidamide. The structure of the said compound is showed as formula (I). Ethoxy combretastatins possess potent tubulin polymerization inhibitory activity and can be used for the treatment of inhibiting tumor or neovascular.
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Page/Page column 7; fig.1
(2009/07/17)
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- Immobilized methyltrioxo rhenium (MTO)/H2O2 systems for the oxidation of lignin and lignin model compounds
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A convenient and efficient application of heterogeneous methylrhenium trioxide (MTO) systems for the selective oxidation of lignin model compounds and lignins is reported. Environmental friendly and low-cost H2O2 was used as the oxygen atom donor. Overall, the data presented and discussed in this paper point toward the conclusion that the immobilized heterogeneous catalytic systems based on H2O2/and MTO catalysts are able to extensively oxidize both phenolic and non-phenolic, monomeric, and dimeric, lignin model compounds. Condensed diphenylmethane models were found also extensively oxidized. Technical lignins, such as hydrolytic sugar cane lignin (SCL) and red spruce kraft lignin (RSL), displayed oxidative activity with immobilized MTO catalytic systems. After oxidation, these lignins displayed the formation of more soluble lignin fragments with a high degree of degradation as indicated by the lower contents of aliphatic and condensed OH groups, and the higher amounts of carboxylic acid moieties. Our data indicate that immobilized MTO catalytic systems are significant potential candidates for the development of alternative totally chlorine-free delignification processes and environmental sustainable lignin selective modification reactions.
- Crestini, Claudia,Caponi, Maria Chiara,Argyropoulos, Dimitris S.,Saladino, Raffaele
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p. 5292 - 5302
(2008/02/07)
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- Methyltrioxorhenium: A new catalyst for the activation of hydrogen peroxide to the oxidation of lignin and lignin model compounds
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The oxidative degradation of lignin under totally chlorine free conditions is one of the most relevant targets for the design of environmental friendly pulping and bleaching industrial processes. Methyltrioxorhenium was found a powerful and promising catalyst for the oxidation of both phenolic and non-phenolic lignin model compounds by use of hydrogen peroxide as primary oxidant. Three different technical lignins, hydrolytic sugar cane lignin (SCL), red spruce kraft lignin (RSL) and a hardwood organosolvent lignin (OSL), that are representative examples of widely diffused para-hydroxyphenyl-guaiacyl, guaiacyl and guaiacyl-syringyl lignins, were also extensively degraded under similar experimental conditions.
- Crestini, Claudia,Pro, Paola,Neri, Veronica,Saladino, Raffaele
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p. 2569 - 2578
(2007/10/03)
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- An efficient synthesis of benzofurans and their application in the preparation of natural products of the genus Calea
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The intramolecular cyclization of the β-substituted olefins methyl 2-aryloxy-3-dimethylaminopropenoates 3a-3f catalyzed by Lewis acids leads to a short and novel synthesis of benzofurans 2a-2f. When the olefins 4-dimethylamino-3-aryloxy-3-buten-2-ones 4a-4f were used, the cyclization process was faster and provided the corresponding substituted 2-acetylbenzofurans 1a-1f. Among the latter, naturally occurring compounds calebertin (1a), caleprunin A (1b), and caleprunin B (1c) were prepared in good overall yields. These benzofurans were also obtained by direct treatment under MW irradiation of the precursors 1-aryloxypropan-2-ones 7a-7c with DMFDMA, followed by addition of the catalyst, resulting in a route that was one step shorter.
- Del Carmen Cruz, María,Tamariz, Joaquín
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p. 10061 - 10072
(2007/10/03)
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- Competitive formation of β-amino acids, propenoic, and ylidenemalonic acids by the Rodionov reaction from malonic acid, aldehydes, and ammonium acetate in alcoholic medium
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The Rodionov reaction of 49 available aliphatic and aromatic aldehydes with malonic acid and ammonium acetate in alcoholic medium, resulting in formation of β-amino acids, propenoic, and ylidenemalonic acids, was studied. Certain regioselectivity regularities of the reaction were revealed. Among the variety of ketones studied, cyclohexanone is the only whose reaction yields a β-amino acid. Unusual dehydrofluorination of 6-chloro-2-fluorocinnamic acid under the Rodionov reaction was discovered. 2005 Pleiades Publishing, Inc.
- Lebedev,Lebedeva,Sheludyakov,Kovaleva,Ustinova,Kozhevnikov
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p. 1113 - 1124
(2007/10/03)
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- Compositions containing aromatic aldehydes and their use in treatments
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Disclosed are pharmaceutical and cosmetic compositions containing aromatic aldehyde compounds. Some of the disclosed compositions are useful as topical therapeutics for treating inflammatory dermatologic conditions. Some of the compositions are useful in transdermal and other systemic dose forms for treating other inflammatory conditions in mammals.
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- Iron porphyrin catalyzed oxidation of lignin model compounds: oxidation of phenylpropane and phenylpropene model compounds
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The oxidation of 1-(4-ethoxy-3-methoxyphenyl)propane (2) and 1-(4-ethoxy-3-methoxyphenyl)propene (3) by meso-tetra(2,6-dichloro-3-sulphonatophenyl)porphyrin iron chloride (TDCSPPFeCl, 1) and tert-butylhydroperoxide (t-BuOOH) are discussed.In addition to a Cα-hydroxylation product, demethoxylation and direct aromatic ring cleavage products were found in the oxidation of 2.When 3 was oxidized by 1 and t-BuOOH in aqueous acetonitrile, an acetonitrile-incorporated product was found.A mechanism for the oxidation of 3 is proposed. - Keywords: lignin; ligninase; iron porphyrin; model; degradation
- Cui, Futong,Dolphin, David
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p. 2153 - 2157
(2007/10/03)
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- ESTER LINKAGES BETWEEN LIGNIN AND GLUCURONIC ACID IN LIGNIN-CARBOHYDRATE COMPLEXES FROM FAGUS CRENATA
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Conjugate acid oxidation of benzyl esters with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and trifluoroacetic acid (TFA) was applied to the binding site analysis of ester linkages between lignin and glucuronoxylan in Fagus crenata wood.Based on the conjugate acid DDQ-oxidation of a watersoluble lignin-carbohydrate complex (LCC-WE) from the beech wood, the frequency of the ester bonds between the lignin and glucuronic acid residue of glucuronoxylan was determined to be 1.6 per molecule of LCC-WE. - Key words: Fagus crenata; Fagaceae; lignin-carbohydrate complex (LCC); 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ).
- Imamura, Takeshi,Watanabe, Takashi,Kuwahara, Masaaki,Koshijima, Tetsuo
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p. 1165 - 1174
(2007/10/02)
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- Studies on chromium trioxide-based oxidative coupling reagents and synthesis of lignan-cagayanone
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Oxidation of 1-arylprop-1-enes by using the reagent system CrO3-HClO4- CH3CN at 0-5°C gave seven products from methyl isoeugenol, five from ethyl isoeugenol, four from benzyl isoeugenol, and five from isosafrole. Cagayanone was obtained from isosafrole in one step. The structures of the products were elucidated and the mechanism of their formation is discussed.
- Kuo,Lin
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p. 1507 - 1512
(2007/10/02)
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- Synthesis of stable water-soluble chemiluminescent 1,2-dioxetanes and intermediates therefor
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A novel synthesis of compounds having the formula: STR1 wherein T is a stabilizing spiro-linked polycycloalkylidene group, R3 is a C1 -C20 alkyl, aralkyl or heteroatom containing group, Y is an aromatic fluorescent chromophore, and Z is a cleavable group which, when cleaved, induces decomposition of the dioxetane ring and emission of optically detectable light, is disclosed. A tertiary phosphorous acid alkyl ester of the formula: wherein R1 is a lower alkyl group, is reacted with an aryl dialkyl acetal produced by reacting a corresponding aryl aldehyde with an alcohol of the formula: wherein R3 is as defined above, to produce a 1-alkoxy-1-arylmethane phosphonate ester of the formula: STR2 reacting the phosphonate with base to produce a phosphonate-stabilized carbanion, reacting the carbanion with a ketone of the formula: wherein T is as defined above, to produce an enol ether of the formula: STR3 then oxygenating the double bond in the enol ether to give the corresponding 1,2-dioxetane compound.
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- Process for nucleophilic fluoroalkylation of aldehydes
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Aryl difluoromethyl sulfone adds to alkehydes under phase transfer conditions to give novel substituted alcohols of the general formula wherein R is an aryl, cycloaliphatic, sec- or tert-aliphatic, or heterocyclic group and Ar is an aryl group. The substituted alcohols of formula I are of particular utility as intermediates in the synthesis of a variety of useful end products. For example, the products of formula I may be utilized in desulfonylation reactions, oxidation reactions and fluorination reactions.
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- Evidence for Deuterium Retention in Products after Enzymatic C-C and Ether Bond Cleavages of Deuterated Lignin Model Compounds
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The mechanism of C-C and ether bond cleavages of Cα- or Cβ-deuterated β-O-4 and β-1 lignin substructure models and the vicinal diol compounds catalyzed by the enzyme system from Phanerochaete chrysosporium culture was investigated.The enzymatic oxidation of β-O-4 lignin model compounds in the presence of H2O2 and O2 yielded C6-Cα-derived benzaldehyde, and Cβ-Cγ-derived product together with the arylglycerol product.Likewise, the β-1 models and the diol compounds also underwent the C-C bond cleavage, yielding C6-Cα-derived benzaldehyde and the arylglycol product.The results demonstrated that the D-labels at Cα and Cβ of the substrates were retained in the products after the Cα-Cβ and ether bond cleavages.
- Habe, Tsuyoshi,Shimada, Mikio,Umezawa, Toshiaki,Higuchi, Takayoshi
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p. 3505 - 3510
(2007/10/02)
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- Degradation Pathway of Arylglycerol-β-aryl Ethers by Phanerochaete chrysosporium
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The degradation pathway for the most important β-O-4 lignin substructure with a white rot fungus, Phanerochaete chrysosporium, was investigated, and the following conclusions were obtained. a) The allyl alcohol end group attached to the β-O-4 substructure was degraded to a formyl group via a glycerol group. b) Arylglycerol was formed by the cleavage of the β-O-4 substructure without involvement of the hydroxylation reaction at Cβ. c) 18O was not incorporated from 18O2 into arylglycerol nor phenol liberated by the degradation of the β-O-4 substrucrure, but was incorporated into the benzyl alcohol derivative formed by Cα-Cβ cleavage. d( Two alternative degradation pathway of the β-O-4 substructure, a pathway via arylglycerol and direct oxygenative Cα-Cβ cleavage, are proposed
- Umezawa, Toshiaki,Nakatsubo, Fumiaki,Higuchi, Takayoshi
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p. 2677 - 2682
(2007/10/02)
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- Process for the methylation of hydroxybenzene derivatives
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A method is disclosed of alkylating substituted hydroxybenzenes, particularly substituted hydroxybenzaldehydes, by reacting the hydroxybenzene compound with a dialkylsulfate in the presence of an alkali metal carbonate, substantially in the absence of a solvent. The alkoxylated product is obtained in yields substantially close to theoretical.
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