23635-30-5Relevant articles and documents
Synthesis and study of 2-acetyl amino-3-[4-(2-amino-5-sulfo-phenylazo)- phenyl]-propionic acid: A new class of inhibitor for hen egg white lysozyme amyloidogenesis
Maity, Sibaprasad,Kumar, Ravi,Maity, Suman Kumar,Jana, Poulami,Bera, Santu,Haldar, Debasish
, p. 530 - 536 (2013/05/22)
The compounds capable of blocking the aggregation of amyloidogenic proteins may have therapeutic potentials. We report on the synthesis of 2-acetyl amino-3-[4-(2-amino-5-sulfo-phenylazo)-phenyl]-propionic acid as an HEWL (hen egg white lysozyme) amyloid inhibitor starting from phenylalanine. The compounds arrest the monomers and exhibit anti-aggregating activity. Moreover, the acetyl derivative 1 served as a better inhibitor than the trifluoroacetyl derivative 2 against in vitro amyloid fibrillogenesis of the HEWL model system.
Direct ortho iodination of β- and γ-aryl alkylamine derivatives
Barluenga, Jose,Alvarez-Gutierrez, Julia M.,Ballesteros, Alfredo,Gonzalez, Jose M.
, p. 1281 - 1283 (2008/03/27)
Two in one! A trifluoroacetamide protecting group not only masks an amine functionality, but also mimics peptidyl directing effects as a controlling unit in an efficient ortho iodination of a variety of biologically relevant small molecules (see example). (Chemical Equation Presented).
Biotransformations in low-boiling hydrofluorocarbon solvents
Saul, Simon,Corr, Stuart,Micklefield, Jason
, p. 5519 - 5523 (2007/10/03)
Solvent solutions: Low-boiling hydrofluorocarbons (see examples) are excellent solvents for lipase-catalyzed reactions and ideal replacements for conventional organic solvents and supercritical fluids as media for nonaqueous biotransformations. Notably increased rates, yields, and enantioselectivities were observed with the model kinetic resolution of (±)-1-phenylethanol and the desymmetrization of weso-2-cyclopentene-1 ,4-diol.
Use of N-trifluoroacetyl-protected amino acid chlorides in peptide coupling reactions with virtually complete preservation of stereochemistry
Jass, Paul A.,Rosso, Victor W.,Racha, Saibaba,Soundararajan, Nachimuthu,Venit, John J.,Rusowicz, Andrew,Swaminathan, Shankar,Livshitz, Julia,Delaney, Edward J.
, p. 9019 - 9029 (2007/10/03)
The use of protected amino acid chlorides for peptide coupling reactions has long been avoided due to the extensive racemization that commonly occurs during either the acid chloride formation or the coupling reaction itself. Conditions are described which
Mild regeneration of the carboxylic group of amino acid alkyl esters by aqueous methanolic sodium hydrogen carbonate via 5-oxazolidinones
Allevi, Pietro,Anastasia, Mario
, p. 7663 - 7665 (2007/10/03)
A simple racemization-free procedure allows the regeneration of the carboxylic acid group of amino acid alkyl esters by way of an intermediate 5-oxazolidinone which is hydrolyzed by treatment with sodium hydrogen carbonate in aqueous methanol.
The enzyme-catalysed stereoselective transesterification of phenylalanine derivatives in supercritical carbon dioxide
Smallridge, Andrew J.,Trewhella, Maurie A.,Wang
, p. 259 - 262 (2007/10/03)
The subtilisin Carlsberg catalysed transesterification of N-acetyl phenylalanine methyl ester (1), N-acetyl phenylalanine ethyl ester (2), N-trifluoroacetyl phenylalanine methyl ester (3) and N-trifluoroacetyl phenylalanine ethyl ester (4) was studied in supercritical carbon dioxide. The water content of the reaction affects the reactivity of the system; for the transesterification of the methyl esters with ethanol the optimum concentration of water was determined to be about 0.74 M, while for the transesterification of the ethyl esters with methanol the optimum concentration of water was about 1.3 M. The conversion is also dependent upon the concentration of alcohol; for ethanol, 2% v/v gives the maximum conversion, whilst for methanol, only 0.8-1. 2% v/v is required. This is probably due to a difference in the solubility of the substrates in the two alcohol/supercritical carbon dioxide mixtures. The reaction is highly stereoselective, in all cases no evidence for reaction of the D-isomer could be detected by chiral gas chromatography.
Asymmetric Bis(alkoxycarbonylation) Reaction of Homoallylic Alcohols Catalyzed by Palladium in the Presence of Cu(I) Triflate Using the Chiral Bioxazoline Ligand
Ukaji, Yutaka,Miyamoto, Masanori,Mikuni, Miho,Takeuchi, Susumu,Inomata, Katsuhiko
, p. 735 - 742 (2007/10/03)
Palladium-catalyzed asymmetric intra- and intermolecular bis(alkoxycarbonylation) reactions of homoallylic alcohols in the presence of copper(I) triflate were achieved by using the chiral bioxazoline ligand, (S,S)-4,4′-dibenzyl-4,4′,5,5′-tetrahydro-2,2′-bioxazole, under normal pressure of carbon monoxide and oxygen at 25°C to give the corresponding optically active γ-butyrolactones in 19 - 65% ee.
Chiral Recognition of Amino Acid Derivatives: An NMR Investigation of the Selector and the Diastereomeric Complexes
Spisni, Alberto,Corradini, Roberto,Marchelli, Rosangela,Dossena, Arnaldo
, p. 684 - 688 (2007/10/02)
A tetraamidic selector containing two chiral synthons ((S)-phenylalanine) spaced by a 3,6,9-oxadecanoyl bridge (Phe-3-O-TA) (1) was used as stationary phase in capillary GC to perform chiral resolution of N-TFA-amino esters.In this paper we report an investigation on the mechanism of chiral recognition by NMR spectroscopy (1D and 2D, COSY, NOESY, and J-resolved experiments and 13C relaxation times).First the conformation of the selector in CDCl3 and CD3OD was studied to evaluate the structural features that might justify the enantiomeric discrimination ability.Thenthe self-associations of the selector and of the enantiomers (S)- and (R)-methyl (2a,2b) and (S)- and (R)-n-butyl N-TFA-phenylalaninate (3a, 3b) were investigated at variable temperature and concentration in CDCl3.Finally, titration experiments were carried out to detect the sites of the binding interactions between the selector and the enantiomers.A simple recognition mode is proposed to account for both the enantioselectivity of the phase and the elution order of the enantiomers observed in GC (t'RS).This is the first spectroscopic study on the mechanism of chiral recognition in GC concerning the real phase and not a model system.