- Structure-supercooling property relationship of phenylethyl phenylacetate derivatives and analogue
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In this paper, three new compounds were synthesized by introduction of benzyloxy group to phenylethyl phenylacetate (PPA) and shorting the flexible ester linker. NMR spectra and mass spectra are achieved to confirm the structure of the compounds. The solid-liquid and liquid-solid phase change behaviors of PPA and these three compounds were explored by direct observation and differential scanning calorimetry (DSC) measurements. It was found that all four compounds would form supercooled liquids during a heating-cooling cycle. The supercooling degree is as large as 44 °C or above. The effects of benzyloxy group and the flexible linker on the phase transition processes as well as the supercooling degrees were discussed in detail with the computational optimized geometry of isolated molecules. It was revealed that the dihedral angles between adjacent phenyl rings play a significant role in tuning their phase transition temperatures. This work also discovers the high enthalpies of PPA derivatives and analogues in both solid-liquid and liquid-solid phase transition processes, making them great potentials for the thermal energy control of appropriate working temperature regions.
- Li, Wei,Liu, Dongzhi,Liu, Simin,Yin, Defei,Zhou, Xueqin
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- Synthesis and evaluation of new sesamol-based phenolic acid derivatives with hypolipidemic, antioxidant, and hepatoprotective effects
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The objective of this study is to synthesize a series of sesamol-based phenolic acid derivatives, which were designed by combination principle. The hypolipidemic activity of all these compounds was preliminarily screened by acute hyperlipidemic mice model induced by Triton WR 1339, in which compound T6 exhibited more significant reducing plasma TG and TC than fenofibrate. Compound T6 was also found to obviously decrease TG and TC both in the plasma and hepatic tissue of high-fat-diet-induced hyperlipidemic mice. Moreover, T6 showed hepatoprotective effects, which remarkable amelioration in characteristic liver enzymes was examined and the histopathological observation displayed that compound T6 inhibited lipids accumulation in the hepatic. The levels of PPAR-α receptor related to lipids metabolism in hepatic tissue were upregulated after T6 treatment. Other potent effects of T6 such as antioxidant and anti-inflammatory activity were also observed. On the bases of these findings, compound T6 may serve as an effective hypolipidemic and hepatoprotective agent. [Figure not available: see fulltext.]
- Xie, Yundong,Liu, Jiping,Shi, Yongheng,Bin Wang,Wang, Xiaoping,Wang, Wei,Sun, Meng,Xu, Xinya,He, Shipeng
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p. 1688 - 1702
(2021/07/26)
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- Method for synthesizing salidroside by using [Rmim][OSO2OR]-Lewis acid ionic liquid system
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The invention belongs to the technical field of catalytic synthesis and particularly relates to a method for synthesizing salidroside by using a [Rmim][OSO2OR]-Lewis acid ionic liquid system. According to the method, the salidroside compound is synthesized by using ionic liquid [Rmim][OSO2OR]. The synthesis of the ionic liquid provided by the invention needs only a one-step reaction, and atoms ofraw materials in a synthetic reaction of the ionic liquid are utilized by 100%, and thus, the reaction is an atomic-economical-efficiency reaction with simple and convenient operation. The method provided by the invention is environmentally friendly and is mild in reaction conditions and simple in aftertreatment, the problems such as environmental pollution caused by tedious synthesis of the ionicliquid used during the existing O-Glycosylation of a glycosyl trichloroacetimidate donor by using an ionic liquid system, thermal energy consumption, atom waste and a non-atomic-economical-efficiencyreaction are solved, and meanwhile, the problems such as environmental pollution and tedious aftertreatment caused by the existing salidroside drug chemical-synthesis in organic solvents are solved.
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Paragraph 0028
(2018/04/26)
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- DDQ-Promoted Benzylic/Allylic sp3 C-H Activation for the Stereoselective Intramolecular C-N Bond Formation: Applications to the Total Synthesis of (-)-Codonopsinine, (+)-5-epi-Codonopsinine, (+)-Radicamine B, and (-)-Codonopsinol
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This is the first report on an intramolecular C-N bond formation of an amide-tethered benzylic/allylic system using DDQ under neutral conditions which has been successfully applied to the total synthesis of naturally occurring pyrolidine alkaloids. The key steps for the synthesis of corresponding precursors involve Julia-Kociensky olefination/cross-metathesis and dihydroxylation reactions, and this methodology is also extended to the ω-unsaturated N-sulfanilamide to furnish piperidines.
- Lingamurthy, Macha,Jagadeesh, Yerri,Ramakrishna, Katakam,Rao, Batchu Venkateswara
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p. 1367 - 1377
(2016/03/01)
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- Synthesis of a benzyl-protected analog of arenarioside, a trisaccharide phenylpropanoid glycoside
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A benzyl-protected analog of the phenylpropanoid glycoside arenarioside, (4-benzyloxyphenyl)ethyl α-l-rhamnopyranosyl-(1→3)-4-O-[(E)-3,4-di-O-benzyl-caffeoyl]-[β-d-xylopyranosyl-(1→6)]-β-d-glucopyranoside (22), was synthesized through two different routes from d-glucose. This is the first approach on the synthesis of a trisaccharide phenylpropanoid glycoside, although the benzyl-protecting group in the backbone of the arenarioside analog could not be removed by conventional debenzylation procedures.
- Zhou, Feng-Yan,She, Jin,Wang, Yan-Guang
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p. 2469 - 2477
(2007/10/03)
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- Highly chemoselective hydrogenation method using novel finely dispersed palladium catalyst on silk-fibroin: Its preparation and activity
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A palladium-fibroin complex (Pd/Fib) was prepared by soaking silk-fibroin in MeOH solution of Pd(OAc)2 for 2 days (under Ar atmosphere) - 4 days (under air). Pd(OAc)2 was gradually absorbed by fibroin and the rapid reduction of fibroin conjugated Pd(OAc)2 proceeded with MeOH as a reductant at room temperature to be the Pd(0) complex. Pd/Fib catalyzed chemoselective hydrogenation of acetylenes, olefins and azides in the presence of aromatic ketones and aldehydes, halides, N-Cbz protective groups and benzyl esters which are readily hydrogenated using Pd/C or Pd/C(en) as a catalyst.
- Ikawa, Takashi,Sajiki, Hironao,Hirota, Kosaku
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p. 2217 - 2231
(2007/10/03)
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- Efficient synthesis of 1-Benzyloxyphenyl-3-phenylacetones
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1-[(Benzyloxy)phenyl]-3-phenylacetones 1a-c have been conveniently synthesized by acylation of the PhCH2Li-DABCO complex with their respective N-methyl O-methyl hydroxamates 5a-c. In four steps, ketones 1a-c having ortho-, meta- and para-benzyloxy substituents were obtained in 42-51% overall yields from commercially available 2-(hydroxyphenyl)acetic acids.
- Mannekens,Tourwe,Lubell
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p. 1214 - 1216
(2007/10/03)
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- SPIRO-SUBSTITUTED AZACYCLES AS MODULATORS OF CHEMOKINE RECEPTOR ACTIVITY
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The present invention is directed to spiro-substituted azacycles of the Formula 1: STR1 (wherein R 1, l, m, Q, W, X, Y, and Z are defined herein) which are useful as modulators of chemokine receptor activity. In particular, these compounds are useful as modulators of the chemokine receptors CCR-1, CCR-2, CCR-2A, CCR-2B, CCR-3, CCR-4, CCR-5, CXCR-3, and/or CXCR-4.
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- A novel type of Pd/C-catalyzed hydrogenation using a catalyst poison: Chemoselective inhibition of the hydrogenolysis for O-benzyl protective group by the addition of a nitrogen-containing base
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A mild and chemoselective hydrogenation method for a variety of reducible functional groups distinguishing front aliphatic and aromatic' benzyl ethers was accomplished by the addition of an appropriate nitrogen- containing base to the Pd/C-catalyzed hydrogenation system.
- Sajiki, Hironao,Hirota, Kosaku
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p. 13981 - 13996
(2007/10/03)
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- Synthesis and protein kinase C inhibitory activities of balanol analogues with modification of 4-hydroxybenzamido moiety
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A series of racemic balanol analogues with modification of the benzamido moiety of balanol have been synthesized and evaluated for their inhibitory activities against human protein kinase C isozymes (PKC-alpha, -beta I, -beta II, -gamma, -delta, -epsilon, and -eta). The structural modification includes replacement of the 4-hydroxyphenyl group with variously substituted phenyl rings, substitution of the amide linkage with a sulfonamide or an ester, and replacement of the 4-hydroxyphenyl substructure with a hydroxyl substituted indole or a hydroxybenzyl group. In general, these analogues were found to be less potent than balanol, but a number of analogues were identified with improved isozyme selectivity. The structure-activity relationship studies of these analogues also indicated that (1) the optimal general PKC inhibition requires a free 4-hydroxyl group in the benzamido portion of the molecule, (2) the amide linkage of the benzamido moiety is important for PKC inhibition, and (3) the conformation associated with the benzamido moiety seems to have a profound effect on PKC inhibition. The requirement of a free 4-hydroxyl group in conjunction with an appropriate conformation of the benzamido moiety for optimal PKC inhibition suggests that the 4-hydroxyphenyl group may be involved in a specific inhibitor-enzyme interaction important for PKC inhibition.
- Hu, Hong,Mendoza, Jose S.,Lowden, Christopher T.,Ballas, Lawrence M.,Janzen, William P.
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p. 1873 - 1882
(2007/10/03)
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- Total syntheses of spidamine and joramine, polyamine toxins from the joro spider, Nephila clavata
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In order to confirm the structures of spidamine and joramine, identified from the venom of a spider (nephila clavata), we convergently synthesized both compounds, which have a common side chain of N-(L-asparaginyl)-N'-(3- aminopropyl-β-alanyl)-1,5-pentanediamine. A synthon of the common side chain was synthesized by starting with n-propanolamine which was converted to 7- azido-N-benzyloxycarbonyl-4-azaheptanoic acid N-hydroxysuccinimidyl ester. The ester was coupled with tert-butyloxycarbonyl-L-asparaginyl-1,5- pentanediamine to give the synthon of the common side chain. In the final synthesis of spidamine, the synthon of the common side chain was reacted with 2,4-dibenzyloxyphenylacetic acid N-hydroxysuccinimidyl ester, obtained by Willgerodt-kindler reaction of 2,4-dihydroxyacetophenone. The protected spidamine was catalytically hydrogenated to remove protective groups, affording spidamine itself in 13% yield from n-propanolamine. In the final synthesis of joramine, the synthon of the common side chain was reacted with 4-benzyloxyphenyl acetic acid N-hydroxysuccinimidyl ester. The protected joramine was also catalytically hydrogenated to produce joramine itself in 11% yield. The conformations of both synthesized compounds were analyzed by 1H-NMR and 13C-NMR. Their blocking activities on glutamate receptors were examined using lobster neuromuscular synapses.
- Chiba, Tadashige,Akizawa, Toshifumi,Matsukawa, Motomi,Nishi, Masatoshi,Kawai, Nobufumi,Yoshioka, Masanori
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p. 972 - 979
(2007/10/03)
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- SYNTHESIS OF ATR AND LIGHT SENSITIVE CIS-PHENOLIC CYCLOPROPANE DERIVATIVES
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The synthesis of several cis-phenolic cyclopropanes, 6, 7, 8 and 13 is described.These cyclopropanes are new potential antiestrogens.A hydrogenolysis study of precursors, 5b, 5c, 5d, 10, 11, and 12, and a novel method for the prevention of gem-dichlorocyclopropane ring-opening during hydrogenolysis are discussed.
- Afzal, Jalees,Magarian, Robert A.,Griffin, May,Pento, J. Thomas
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p. 3061 - 3068
(2007/10/02)
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