50299-14-4Relevant academic research and scientific papers
Synthesis of L-α-amino-ω-bromoalkanoic acid for side chain modification
Watanabe, Louis A.,Jose, Binoy,Kato, Tamaki,Nishino, Norikazu,Yoshida, Minoru
, p. 491 - 494 (2004)
L-α-Amino-ω-bromoalkanoic acids with side chain lengths varying from 4 to 10 methylene units have been conveniently synthesized as useful intermediates for the synthesis of functionalized non-natural amino acids.
Influence of Sulfoxide Group Placement on Polypeptide Conformational Stability
Gharakhanian, Eric G.,Bahrun, Ehab,Deming, Timothy J.
supporting information, p. 14530 - 14533 (2019/10/02)
The synthesis of a homologous series containing five new nonionic sulfoxide containing polypeptides was described. Sulfoxide groups bestowed water solubility for all homologues, which allowed their use as a model for study of helix-coil transitions in water while avoiding contributions from charged groups or phase separation. Polypeptides were found to adopt chain conformations in water that were dependent on distance of sulfoxides from chain backbones, overall side-chain lengths, and solvent. These results allow preparation of polypeptide segments with different chain conformations without changing chemical functionality for potential use in structural studies and functional applications.
Epoxy amino acids produced from allylglycines intramolecularly cyclised to yield four stereoisomers of 4-hydroxyproline derivatives
Krishnamurthy, Suvratha,Arai, Toru,Nakanishi, Kanae,Nishino, Norikazu
, p. 2482 - 2490 (2014/01/06)
Derivatives of 2-amino-4-pentenoic acid (allylglycine) were efficiently resolved using Subtilisin or acylase. The side-chain unsaturated bond of the enantiomerically pure amino acid with tert-butoxycarbonyl (Boc) protection was smoothly epoxidized with m-chloroperbenzoic acid. When the Boc protection of the amino group was removed, the amino group intramolecularly attacked the side-chain epoxide, generating compounds with five-membered rings: the 4-hydroxyproline derivatives. Two diastereomeric products were formed through the cyclisation reaction, for example, (2S,4S)-4-hydroxyproline benzyl ester (cis-8) and (2S,4R)-4-hydroxyproline benzyl ester (trans-8) were formed from (2S)-amino acid with a side-chain epoxide. Compound (2S,4S)-4-hydroxyproline benzyl ester (cis-8) was transformed to a lactone (cis-hydroxyproline lactone, 10) with the removal of benzyl alcohol. The cis-conformation was essential for the intramolecular ester exchange reaction; in fact, no lactone formation was observed for the trans isomer (trans-8). The separation of cis-hydroxyproline lactone and the trans-isomeric hydroxyproline benzyl ester was facile and clear, in contrast to the difficult separation of cis- and trans-hydroxyproline derivatives. Thus, two diastereomers of hydroxyproline derivatives for l-hydroxyproline and also for d-hydroxyproline were obtained, i.e., four diastereomers of hydroxyproline derivatives.
Use of hydrolases for the synthesis of cyclic amino acids
Lloyd, Richard C.,Lloyd, Michael C.,Smith, Mark E. B.,Holt, Karen E.,Swift, Jonathan P.,Keene, Philip A.,Taylor, Stephen J. C.,McCague, Raymond
, p. 717 - 728 (2007/10/03)
The synthesis of several cyclic amino acids that have all the necessary structural features to make them ideal scaffolds for use in medicinal chemistry is described. A key step in each synthesis is the use of hydrolase enzymes to define a chiral centre. I
Chemoenzymatic synthesis of the four diastereoisomers of 4-hydroxypipecolic acid from N-acetyl-(R,S)-allylglycine: Chiral scaffolds for drug discovery
Lloyd, Richard C.,Smith, Mark E. B.,Brick, Dean,Taylor, Stephen J. C.,Chaplin, David A.,McCague, Raymond
, p. 762 - 766 (2013/09/06)
All four diastereoisomers of 4-hydroxypipecolic acid were prepared in a form conveniently protected for drug discovery applications with the use of industrially scaleable methodology. Resolution of the racemic starting material using proprietary acylases followed by an acyliminium ion cyclisation gave diastereomeric mixtures of 4-formyloxypipecolic acid, which were differentiated using an enzyme-catalysed hydrolysis. The products were separated by partition, and by following a sequence of straightforward chemical steps, the individual stereoisomers of the protected 4-hydroxypipecolates were crystallized to optical purity in 100 g quantities.
Amino acid derivative anticonvulsant
-
, (2008/06/13)
The present invention relates to compounds of the formula STR1
Synthesis of (Optically Active) Sulfur-Containing Trifunctional Amino Acids by Radical Addition to (Optically Active) Unsaturated Amino Acids
Broxterman, Quirinus B.,Kaptein, Bernard,Kamphuis, Johan,Schoemaker, Hans E.
, p. 6286 - 6294 (2007/10/02)
Sulfur-based radicals, generated from R-S-H-type precursors (R = alkyl, acyl) with AIBN, smoothly add to α-allylglycines protected at none, one, or both of the amino acid functions (NH2 and/or CO2H).Sulfur-containing trifunctional amino acids were obtained in good to excellent yields (64-100 percent).The solvent used for the reaction is critical.Optimal results were obtained when both the unsaturated amino acid and RSH dissolve completely in the medium (dioxane/water or methanol/water are good solvent systems).The scope of the reaction includes α-substituted α-allylglycine derivative and derivatives as well as β-substituted β-allyl-β-amino alcohols.In the case of optically active α-allylglycine derivatives, radical addition is accompanied by a small amount of racemization, the amount depending on the type of protection and R-S-H.The products are easily optically enriched by crystallization.Addition of sulfur-based radicals to α-allylglycine is believed to be an example of a general method for synthesizing optically active trifunctional amino acids from unsaturated amino acids.
