3397-33-9Relevant articles and documents
Ynamide-Mediated Thiopeptide Synthesis
Yang, Jinhua,Wang, Changliu,Xu, Silin,Zhao, Junfeng
supporting information, p. 1382 - 1386 (2019/01/08)
Exploration of the full potential of thioamide substitution as a tool in the chemical biology of peptides and proteins has been hampered by insufficient synthetic strategies for the site-specific introduction of a thioamide bond into a peptide backbone. A novel ynamide-mediated two-step strategy for thiopeptide bond formation with readily available monothiocarboxylic acids as thioacyl donors is described. The α-thioacyloxyenamide intermediates formed from the ynamides and monothiocarboxylic acids can be purified, characterized, and stored. The balance between their activity and stability enables them to act as effective thioacylating reagents to afford thiopeptide bonds under mild reaction conditions. Amino acid functional groups such as OH, CONH2, and indole NH groups need not be protected during thiopeptide synthesis. The modular nature of this strategy enables the site-specific incorporation of a thioamide bond into peptide backbones in both solution and the solid phase.
C2 symmetrical nickel complexes derived from α-amino amides as efficient catalysts for the enantioselective addition of dialkylzinc reagents to aldehydes
Escorihuela, Jorge,Altava, Belen,Burguete, M. Isabel,Luis, Santiago V.
, p. 551 - 558 (2013/07/27)
A series of C2 symmetrical 1:2 Ni:L complexes derived from α-amino amides were studied for the enantioselective addition of dialkylzinc reagents to aldehydes. Different structural elements on the ligands seem to play an important role in determining the observed enantioselectivity. Through optimization of structure and reaction conditions, the best ligand provided secondary alcohols in excellent yields (up to 98%) and enantioselectivity of up to 99% ee for (R)-enantiomer. A transition state model has been proposed to explain the observed enantioselectivities based on computational calculations at the DFT level. Very interestingly, calculations suggest a coordination model of the aldehyde to the metal complex through association of a lone pair of the carbonyl oxygen to the hydrogen atom of an amino group.
Direct PCR amplification of various modified DNAs having amino acids: Convenient preparation of DNA libraries with high-potential activities for in vitro selection
Kuwahara, Masayasu,Hanawa, Kazuo,Ohsawa, Kazuomi,Kitagata, Rina,Ozaki, Hiroaki,Sawai, Hiroaki
, p. 2518 - 2526 (2007/10/03)
We synthesized modified 2′-deoxyuridine triphosphates bearing amino acids at the C5 position and investigated their substrate properties for KOD Dash DNA polymerase during polymerase chain reaction (PCR). PCR using C5-modified dUTP having an amino acyl group (arginyl, histidyl, lysyl, phenylalanyl, tryptophanyl, leucyl, prolyl, glutaminyl, seryl, O-benzyl seryl or threonyl group) gave the corresponding full-length PCR products in good yield. Although dUTP analogues bearing aspartyl, glutamyl or cysteinyl were found to be poor substrates for PCR catalyzed by KOD Dash DNA polymerase, optimization of the reaction conditions resulted in substantial generation of full-length product. In the case of reaction using dUTP analogue having a cysteinyl group, addition of a reducing agent improved the reaction yield. Thus, PCRs using KOD Dash DNA polymerase together with amino acyl dUTP provide convenient and efficient preparation of various modified DNA libraries with potential protein-like activities.
