350-09-4Relevant articles and documents
Active Controlled and Tunable Coacervation Using Side-Chain Functional α-Helical Homopolypeptides
Barun, Ehab,Bell, Alexandra G.,Deming, Timothy J.,Evans, Declan,Gharakhanian, Eric G.,Houk, K. N.,Scott, Wendell A.
supporting information, p. 18196 - 18203 (2021/11/12)
We report the development of new side-chain amino acid-functionalized α-helical homopolypeptides that reversibly form coacervate phases in aqueous media. The designed multifunctional nature of the side-chains was found to provide a means to actively control coacervation via mild, biomimetic redox chemistry as well as allow response to physiologically relevant environmental changes in pH, temperature, and counterions. These homopolypeptides were found to possess properties that mimic many of those observed in natural coacervate forming intrinsically disordered proteins. Despite ordered α-helical conformations that are thought to disfavor coacervation, molecular dynamics simulations of a polypeptide model revealed a high degree of side-chain conformational disorder and hydration around the ordered backbone, which may explain the ability of these polypeptides to form coacervates. Overall, the modular design, uniform nature, and ordered chain conformations of these polypeptides were found to provide a well-defined platform for deconvolution of molecular elements that influence biopolymer coacervation and tuning of coacervate properties for downstream applications.
The: Ortho -substituent on 2,4-bis(trifluoromethyl)phenylboronic acid catalyzed dehydrative condensation between carboxylic acids and amines
Wang, Ke,Lu, Yanhui,Ishihara, Kazuaki
supporting information, p. 5410 - 5413 (2018/05/30)
2,4-Bis(trifluoromethyl)phenylboronic acid is a highly effective catalyst for dehydrative amidation between carboxylic acids and amines. Mechanistic studies suggest that a 2:2 mixed anhydride is expected to be the only active species, and the ortho-substituent of boronic acid plays a key role in preventing the coordination of amines to the boron atom of the active species, thus accelerating the amidation. This catalyst works for α-dipeptide synthesis.
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