18942-72-8Relevant academic research and scientific papers
First asymmetric aminohydroxylation of acrylamides
Streuff, Jan,Osterath, Brigitte,Nieger, Martin,Muniz, Kilian
, p. 3492 - 3496 (2005)
The first examples of the asymmetric aminohydroxylation of acryl amides are reported. This was accomplished with chiral acrylamides as substrates, which undergo diastereoselective oxidative transformation within the so-called 'second catalytic cycle' with diastereomeric excesses reaching 100:0. The reaction relies solely on the stereochemical information provided by the enantiomerically pure starting materials. A stereochemical model for the observed asymmetric induction is provided.
Intrinsically Photoswitchable α/β Peptides toward Two-State Foldamers
Marafon, Giulia,Crisma, Marco,Moretto, Alessandro
, p. 10217 - 10220 (2018)
A simple, unsaturated, E–Z photoisomerizable β-amino acid, (Z)-3-aminoprop-2-enoic acid, has been introduced into peptide foldamers through a one-pot chemical coupling, based on Pd/Cu-catalyzed olefin oxidative amidation, between two peptide segments carrying, respectively, a -Gly-NH2 residue at the C-terminus and an acryloyl group at the N-terminus. Reversible conversion between the Z and E configurations of the 3-aminoprop-2-enoic linkage was achieved photochemically. A crystallographic analysis on two model compounds shed light on the consequences, in terms of 3D structure and self-association properties, brought about by the different configuration of the unsaturated linkage. As a proof of concept, E–Z photoisomerization of a 3-aminoprop-2-enoic acid residue, inserted as the junction between two conformationally distinct peptide domains (one helical while the other β-sheet promoter), allowed supramolecular self-association to be reversibly turned on/off.
Synthesis of small tripeptide molecules through a catalysis sequence comprising metathesis and aminohydroxylation
Streuff, Jan,Nieger, Martin,Muniz, Kilian
, p. 4362 - 4371 (2008/02/07)
Tripeptidic structures were synthesized by using a combination of two independent consecutive catalytic procedures. Cross-metathesis of N-acroyl amino acid esters yields fumaric amide compounds with exclusive E double-bond geometry. This represents an unp
Models for Use of α-Amino Acids as Chiral Auxiliaries in Asymmetric Diels-Alder Reactions
Bueno, Maria P.,Cativiela, Carlos A.,Mayoral, Jose A.
, p. 6551 - 6555 (2007/10/02)
Three different models, depending on the Lewis acid used as a catalyst and the α-amino acid used as a chiral auxiliary, account for the diastereofacial selectivity obtained in reactions of cyclopentadiene with N-acryloyl derivatives of L-proline, L-phenylalanine, L-alanine, and N-methyl-L-alanine esters.For α-amino acids without an NH group and aluminum catalysts, a reactive conformer with antiplanar enoate conformation similar to those postulated for acrylates with only one center capable of coordination is proposed.These dienophiles form a chelate complex, where the acryloyl moiety is in syn conformation, with TiCl4.For α-amino acids with an NH group, a reactive intermediate with an antiplanar disposition in the acryloyl moiety and the conformation of the amino ester fixed by an intramolecular hydrogen bond accounts for the results with both kinds of catalyst.These models seem to have general application for the use of α-amino acids as chiral auxiliaries in asymmetric Diels-Alder reactions.
