- (S)-Histidine: The ideal precursor for a novel family of chiral aminoacid and peptidic ionic liquids
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(S)-Histidine is shown to be a powerful chiral precursor for the construction of a new series of imidazolium-containing chiral ionic liquids, in which the chiral bifunctional unit of the aminoacid remains unchanged. These ionic materials can be used as building blocks for the synthesis of peptidic ionic liquids.
- Guillen, Frédéric,Brégeon, Delphine,Plaquevent, Jean-Christophe
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- NITROGEN-CONTAINING COMPOUND, METHOD FOR MANUFACTURING THE SAME, AND OPTICAL FUNCTIONAL MATERIAL INCLUDING THE SAME
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PROBLEM TO BE SOLVED: To provide a novel nitrogen-containing compound having luminescence property. SOLUTION: A nitrogen-containing compound represented by the following formula (I) in which RA, RB, R1, R2, R3, R4, and X are either one of the following (1) and (2). SELECTED DRAWING: None COPYRIGHT: (C)2021,JPOandINPIT
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Paragraph 0087-0089
(2021/08/21)
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- A Stereoselective Tyrosinase Model Compound Derived from an m-Xylyl- l -histidine Ligand
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The aim of mimicking enzyme activity represents an important motivation for the development of new catalysts. A challenging objective is the development of chiral complexes for bioinspired enantioselective oxidation reactions. Herein, we report a new chiral dinuclear copper(II) complex based on a m-xylyl-bis(histidine) ligand (mXHI) as a biomimetic catalyst for tyrosinase and catechol oxidase. The new ligand improves a previous system also containing two tridentate N3 units derived from l-histidine that were connected by a short, rigid ethanediamine bridge. In mXHI the bridge is provided by the more extended m-xylyl moiety. The dicopper(II) complex [Cu2(mXHI)]4+ was studied as a catalyst for stereoselective oxidations of enantiomeric couples of chiral catechols of biological interest (L/D-dopa, L/D-dopa methyl ester, and (R/S)-norepinephrine), showing excellent discrimination capability, particularly for the methyl esters of dopa enantiomers. The catechol oxidation was studied in acetate buffer as slightly acidic medium, and a role of acetate as bridging ligand between the two coppers, preorganizing the dinuclear center in a more catalytic efficient structure, could be established. The oxidation of β-naphthol and 3,5-ditertbutylphenol was studied as a model monophenolase reaction. The oxidation proceeds stoichiometrically, and the partial incorporation of 18O into β-naphthol when the reaction was performed using 18O2 suggests the existence of two competitive reaction pathways, a genuine monooxygenase mechanism and a radical pathway. However, the more challenging reaction on derivatives of l-/d-tyrosine did not lead to the desired monooxygenase product but only to products of radical oxidation. Complex [Cu2(mXHI)]4+ was also used for the catalytic sulfoxidation of thioanisole in the presence of hydroxylamine as cosubstrate, in a preliminary attempt to model the reaction of external monooxygenases. The reaction proceeds with 25 turnovers, but the enantiomeric excess of sulfoxide was modest.
- Presti, Eliana Lo,Perrone, Maria L.,Santagostini, Laura,Casella, Luigi,Monzani, Enrico
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p. 7335 - 7344
(2019/06/04)
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- Carnosine protects cardiac myocytes against lipid peroxidation products
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Endogenous histidyl dipeptides such as carnosine (β-alanine-l-histidine) form conjugates with lipid peroxidation products such as 4-hydroxy-trans-2-nonenal (HNE and acrolein), chelate metals, and protect against myocardial ischemic injury. Nevertheless, it is unclear whether these peptides protect against cardiac injury by directly reacting with lipid peroxidation products. Hence, to examine whether changes in the structure of carnosine could affect its aldehyde reactivity and metal chelating ability, we synthesized methylated analogs of carnosine, balenine (β-alanine-Nτ-methylhistidine) and dimethyl balenine (DMB), and measured their aldehyde reactivity and metal chelating properties. We found that methylation of Nτ residue of imidazole ring (balenine) or trimethylation of carnosine backbone at Nτ residue of imidazole ring and terminal amine group dimethyl balenine (DMB) abolishes the ability of these peptides to react with HNE. Incubation of balenine with acrolein resulted in the formation of single product (m/z 297), whereas DMB did not react with acrolein. In comparison with carnosine, balenine exhibited moderate acrolein quenching capacity. The Fe2+ chelating ability of balenine was higher than that of carnosine, whereas DMB lacked chelating capacity. Pretreatment of cardiac myocytes with carnosine increased the mean lifetime of myocytes superfused with HNE or acrolein compared with balenine or DMB. Collectively, these results suggest that carnosine protects cardiac myocytes against HNE and acrolein toxicity by directly reacting with these aldehydes. This reaction involves both the amino group of β-alanyl residue and the imidazole residue of l-histidine. Methylation of these sites prevents or abolishes the aldehyde reactivity of carnosine, alters its metal-chelating property, and diminishes its ability to prevent electrophilic injury.
- Zhao, Jingjing,Posa, Dheeraj Kumar,Kumar, Vijay,Hoetker, David,Kumar, Amit,Ganesan, Smirthy,Riggs, Daniel W.,Bhatnagar, Aruni,Wempe, Michael F.,Baba, Shahid P.
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p. 123 - 138
(2018/11/23)
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- Preparation method of N(pi)-methyl-L-histidine derivative and application thereof to synthesis of whale carnosine
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The invention relates to a preparation method of an N(pi)-methyl-L-histidine derivative and a method for preparing anserine from the synthesized N(pi)-methyl-L-histidine derivative. By the preparationmethod, raw materials are cheap and easy to obtain, the selectivity is good and the yield is high; the operation is simple and easy to implement, a technology is stable, the control is easy, treatment after a reaction is convenient, the product yield is good, the purity is high, and the preparation method can be economically and conveniently applied to industrial production.
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Paragraph 0042-0044
(2019/01/08)
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- Design, synthesis and evaluation of XZH-5 analogues as STAT3 inhibitors
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Inhibition of the signaling pathways of signal transducer and activator of transcription 3 (STAT 3) has shown to be a promising strategy to combat cancer. In this paper we report the design, synthesis and evaluation of a novel class of small molecule inhibitors, that is, XZH-5 and its analogues, as promising leads for further development of STAT3 inhibitors. Preliminary SARs was established for XZH-5 and its derivatives; and the binding modes were predicted by molecular docking. Lead compounds with IC50 as low as 6.5 μM in breast cancer cell lines and 7.6 μM in pancreatic cancer cell lines were identified.
- Daka, Philias,Liu, Aiguo,Karunaratne, Chamini,Csatary, Erika,Williams, Cameron,Xiao, Hui,Lin, Jiayuh,Xu, Zhenghu,Page, Richard C.,Wang, Hong
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p. 1348 - 1355
(2015/03/04)
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- Synthesis of carbamoyl azides from primary amines and carbon dioxide under mild conditions
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(Chemical Equation Presented) Treatment of amines under a carbon dioxide atmosphere with tetramethylphenylguanidine (PhTMG) and diphenylphosphoryl azide (DPPA) in acetonitrile below 0°C provides carbamoyl azides in high to excellent yields. In addition, e
- Garcia-Egido, Eduardo,Fernandez-Suarez, Miryam,Munoz, Luis
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p. 2909 - 2911
(2008/09/19)
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- Synthesis of metal-(pentadentate-salen) complexes: Asymmetric epoxidation with aqueous hydrogen peroxide and asymmetric cyclopropanation (salenH 2: N,N′-bis(salicylidene)ethylene-1,2-diamine)
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It is known that the rates and stereochemical outcomes of epoxidations and cyclopropanations using a metallosalen (salenH2: N,N′- bis(salicylidene)ethylene-1,2-diamine) complex as catalyst are affected by a trans effect of the apical ligand of the complex. By taking into consideration this trans effect, we have synthesized optically active pentadentate salen ligands bearing an imidazole or pyridine derivative as the fifth coordinating group, and have prepared the corresponding manganese(III) and cobalt(II) complexes, in which the fifth ligand is expected to intramolecularly coordinate to the metal center and exert a trans effect. Indeed, high enantioselectivity has been achieved in epoxidations using aqueous hydrogen peroxide as the terminal oxidant and in cyclopropanations with these complexes as catalysts. In general, metallosalen-catalyzed reactions have been carried out in the presence of an excess of a donor ligand; however, the present reactions do not need the addition of any extra donor ligand.
- Shitama, Hiroaki,Katsuki, Tsutomu
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p. 4849 - 4858
(2008/02/03)
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- "N and/or nalpha derivatized, metal and organic protected l-histidine for coupling to biomolecules for highly efficient labeling with [m(oh2)3 (co)3]+ by fac coordination"
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The present invention relates to novel histidine derivatives that can be used for the labeling of biomolecules with radioactive metal tricarbonyls. The new derivatives have a histidine that is derivatized at the Nε and at least protected at the
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Page/Page column 8; 9
(2010/11/26)
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- Facile regiospecific syntheses of N-α,N-1(τ)-dialkyl-L-histidines
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(Chemical Equation Presented) Two diverse methodologies describe the first synthesis of suitably protected N-α,N-1(τ)-dialkyl-L-histidine derivatives. Synthesis of suitably protected N-α,N-1(τ)-dialkyl-L- histidines 7-9 containing different alkyl groups a
- Nayak, Surendra Kumar,Monga, Vikramdeep,Kaur, Navneet,Jain, Rahul
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p. 1265 - 1269
(2008/09/18)
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- N(epsilon) functionalization of metal and organic protected L-histidine for a highly efficient, direct labeling of biomolecules with [Tc(OH2)3(CO)3]+.
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Two different pathways for the introduction of an acetyl group at N(epsilon ) in a N(alpha), N(delta), and -COO protected histidine to afford N(epsilon)-(CH(2)COOH)-histidine derivative 7 b are presented. The purpose of this study is the coupling of 7 b t
- Pak, Jae Kyoung,Benny, Paul,Spingler, Bernhard,Ortner, Kirstin,Alberto, Roger
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p. 2053 - 2061
(2007/10/03)
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- Regiospecific synthesis of 2,3-disubstituted-L-histidines and histamines
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Regiospecific synthesis of 2,3-disubstituted-L-histidines and 2,3-disubstituted histamines starting from L-histidine methyl ester and histamine is reported. The key step involves homolytic free radical alkylation via silver catalyzed oxidative decarboxyla
- Narayanan, Sanju,Vangapandu, Suryanarayana,Jain, Rahul
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p. 1133 - 1136
(2007/10/03)
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- Synthesis of Chiral C2-Symmetric Binucleating Ligands
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The synthesis of a series of chiral enantiomerically pure C2-symmetric binucleating ligands is reported. Ligands of type 1-4, which consist of a phenolic or heterocyclic unit bridging two chiral dihydrooxazole rings, are readily accessible from
- Fahrni, Christoph J.,Pfaltz, Andreas
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p. 491 - 506
(2007/10/03)
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- Regiospecific alkylation of histidine and histamine at N-1 (τ)
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Series of 1-alkyl histidines and histamines have been synthesized by the alkylation of the corresponding 5,6,7,8-tetrahydro-5-oxomidazo[1,5-c]pyrimidines with alkyl halides in aprotic solvents. The method of conversion of the intermediate quaternary salt to the amino acid or amino depends on the nature of the alkyl group.
- Jain, Rahul,Cohen, Louis A.
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p. 5363 - 5370
(2007/10/03)
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- Nτ -substituted histidine derivatives
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A process is disclosed for the preparation of new Nτ -substituted histidine derivatives of the general formula STR1 According to the process, a histidine derivative of the general formula STR2 is reacted with phosgene, and the resultant product is then alkylated and thereafter hydrolyzed with an acid. The products obtained by the process are highly useful for preparation of histidine-analogous proteins and enzymes.
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- Phenacyl-Directed Alkylation of Imidazoles: A New Regiospecific Synthesis of 3-Substituted L-Histidines
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A new strategy for regiospecific imidazole alkylation of suitably protected histidines is described wherein a phenacyl group serves as a protecting group of the distal imidazole nitrogen atom.Alkylation of N-BOC-1-phenacyl-L-histidine methyl ester at N(3)
- Chivikas, Cleo J.,Hodges, John C.
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p. 3591 - 3594
(2007/10/02)
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