15363-84-5Relevant articles and documents
Aliphatic-alcohol-induced opaque-to-transparent transformation and application of solubility theory in a bis-dipeptide-based supramolecular gel
Xiao, Tingting,Zhang, Xiaoyang,Wu, Jingyu,Yang, Jiazhi,Yang, Yong
, p. 879 - 887 (2017)
A bis-dipeptide supramolecular gelator (DMPV) is prepared, based on l-valine moieties having a pyridinyl group and a long fatty diamine. It is found that the gelator can immobilize organic/water binary mixed solvents, and gel-to-gel transitions with unprecedented opaque-to-transparent transformations are observed upon using aliphatic alcohols such as methanol, ethanol, 1-propyl alcohol, and isopropanol as the organic components. Morphological investigations indicate that a reassembly process occurs, and microstructure evolutions from agglomerates to nanofibers are observed. Opaque and transparent assemblies can interconvert, and respond and restore under mechanical force and pH stimuli. Moreover, Hansen and Flory-Huggins parameters are used to investigate the effect of the solvent on the gelation performance of DMPV. This may facilitate the structure and solvent optimizations and aid the development of advanced gel systems.
Aqueous reductive amination using a dendritic metal catalyst in a dialysis bag
Willemsen, Jorgen S.,Van Hest, Jan C.M.,Rutjes, Floris P.J.T.
, p. 960 - 965 (2013)
Water-soluble dendritic iridium catalysts were synthesized by attaching a reactive metal complex to DAB-Am dendrimers via an adapted asymmetric bipyridine ligand. These dendritic catalysts were applied in the aqueous reductive amination of valine while contained in a dialysis bag. Comparable conversions were observed as for the noncompartmentalized counterparts, albeit with somewhat longer reaction times. These results clearly show that the encapsulated catalyst system is suitable to successfully drive a complex reaction mixture with various equilibrium reactions to completion.
Discovery of Novel N-(4-Hydroxybenzyl)valine Hemoglobin Adducts in Human Blood
Degner, Amanda,Carlsson, Henrik,Karlsson, Isabella,Eriksson, Johan,Pujari, Suresh S.,Tretyakova, Natalia Y.,T?rnqvist, Margareta
, p. 1305 - 1314 (2018/12/11)
Humans are exposed to a wide range of electrophilic compounds present in our diet and environment or formed endogenously as part of normal physiological processes. These electrophiles can modify nucleophilic sites of proteins and DNA to form covalent addu
ANTIVIRAL COMPOUNDS
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Paragraph 0642; 0643, (2018/04/13)
The present invention relates to novel compounds of general formula (I) wherein the groups X, and R1 to R4 have the meanings given in the description and claims, process for preparing these compounds and their use as for treating, preventing or ameliorating viral infections and their use for treating, preventing or ameliorating diseases which are associated with PLA2G16.
Hydrogen bond architecture in crystal structures of N-alkylated hydrophobic amino acids
G?rbitz,Leirv?g,Jacobsen
, p. 9631 - 9637 (2015/02/19)
Herein we present the first systematic investigation of hydrogen bonding patterns and crystal packing arrangements of N-alkylated hydrophobic amino acids, including synthesis and single crystal structure determination of five new compounds.
Synthesis of α-amino acids through samarium(II) iodide promoted reductive coupling of nitrones with CO2
Prikhod'Ko, Alexander,Walter, Olaf,Zevaco, Thomas A.,Garcia-Rodriguez, Jaime,Mouhtady, Omar,Py, Sandrine
supporting information; experimental part, p. 3742 - 3746 (2012/09/25)
Several N-benzylnitrones reacted with carbon dioxide in the presence of samarium(II) iodide leading to α-amino acids as the products of reductive C-C coupling. The best selectivities were observed at a carbon dioxide pressure of 50 bar at ambient temperature. The influences of different functional groups in the nitrone backbone and of the coordinating additives to samarium(II) iodide on the product distribution were investigated. The racemic α-amino acids were obtained in up to 70% yield based on HPLC data. A novel approach to the synthesis ofα-amino acids is disclosed, involvingC-carboxylation of nitrones by gaseous CO2 under reductive coupling reaction conditions (SmI2, 0.1 M in THF) at ambient temperature and 50 bar of CO 2 pressure. Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
1,2,3-triazole bound borane compounds, synthesis of, and use in reduction reactions
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Page/Page column 4, (2011/10/12)
A 1,2,3-triazole coordinated borane such as where the B and the R3 groups can be on any of the three N positions and R1, R2, R3, R4, and R5 can be one or more of H, any alkyl, aryl, or subs
Resolution of racemic N-benzyl α-amino acids by liquid-liquid extraction: A practical method using a lipophilic chiral cobalt(III) salen complex and mechanistic studies
Dzygiel, Pawel,Reeve, Toby B.,Piarulli, Umberto,Krupicka, Martin,Tvaroska, Igor,Gennari, Cesare
supporting information; experimental part, p. 1253 - 1264 (2009/04/07)
The efficient resolution of racemic N-benzyl α-amino acids (N-Bn-AA) has been achieved by a liquid-liquid extraction process using the lipophilic chiral salen-cobalt(III) complex [CoIII(3)(OAc)]. As a result of the resolution by extraction, one enantiomer (S) of the N-benzyl α-amino acid predominated in the aqueous phase, while the other enantiomer (R) was driven into the organic phase by complexation to cobalt. The complexed amino acid (R) was then quantitatively released by a reductive (CoIII→Co II) counter-extraction with aqueous sodium dithionite or L-ascorbic acid in methanol. The reductive cleavage allowed to recover the [Co II(3)] complex in good yield, which could be easily re-oxidized to [CoIII(3)(OAc)] with air/AcOH and reused with essentially no loss of reactivity and selectivity. Investigation on the nitrogen substitution indicates that the presence of a single benzyl group on the amino acid nitrogen is important to obtain high enantioselectivity in the extraction process. The kinetic vs. thermodynamic nature of the resolution process was also investigated with an enantiomeric exchange experiment, which shows that the liquid-liquid extraction with [CoIII(3)-(OAc)] is an equilibrium process operating under thermodynamic control. In the absence of a suitable crystal structure of the [CoIII(3)(N-Bn-AA)] complexes, computational and spectroscopic studies were used to investigate how the N-benzyl α-amino acids are accommodated in the "binding pocket" of the chiral cobalt complex. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
A practical approach to the resolution of racemic N-benzyl α-amino acids by liquid-liquid extraction with a lipophilic chiral salen-cobalt(III) complex
Reeve, Toby B.,Cros, Jean-Philippe,Gennari, Cesare,Piarulli, Umberto,De Vries, Johannes G.
, p. 2449 - 2453 (2007/10/03)
(Chemical Equation Presented) Liquidating the assets: Coordination of one enantiomer from a racemic mixture of N-benzyl α-amino acids (N-Bn-AA) to the lipophilic chiral [CoIII(salen)(OAc)] complex results in its extraction into the organic phas
Electrophilic Amination of Amino Acids with N-Boc-oxaziridines: Efficient Preparation of N-Orthogonally Diprotected Hydrazino Acids and Piperazic Acid Derivatives
Hannachi, Jean-Christophe,Vidal, Joelle,Mulatier, Jean-Christophe,Collet, Andre
, p. 2367 - 2373 (2007/10/03)
A general two-step preparation of enantiopure Nα,N β-orthogonally diprotected α-hydrazino acids 1 is developed on a multigram scale. The key reaction is the efficient electrophilic amination of N-benzyl amino acids 6 with N-Boc-oxaziridine 7 and accommodates various functional groups encountered in side chains of amino acids. The cyclic 2,3,4,5-tetrahydro-3-pyridazine carboxylic acid (piperazic acid) derivatives 2 and 3 or the cyclic 3,4-dihydro-3-pyrazolecarboxylate 4 are conveniently prepared from glutamic acid or aspartic acid via orthogonally diprotected α-hydrazino acids 1m and 1n.
