Site-Selective Traceless Staudinger Ligation for Glycoprotein Synthesis Reveals Scope and Limitations GonÅalo J. L. Bernardes, Lars Linderoth, Katie J. Doores, Omar Boutureira, and Benjamin G. Davis*[a] Efficient, chemoselective reactions enable access to well-de-fined post-translationally modified proteins.[1–4] One approach
The so-called traceless Staudinger ligation is a highly attractive process leading to a native amide bond without inclusion of the phosphine oxide in the final product. 6 The synthetic value of this remarkable transformation has been demonstrated by Raines and coworkers with the ligation of complex peptide fragments, possibly best illustrated Jan 01, 2009 · The traceless Staudinger ligation has joined the repertoire of ligation methods for the convergent synthesis of proteins. This method has been used along with others to assemble an entire protein. A putative strategy for the assembly of proteins is depicted in Fig. 4 ( Nilsson et al. , 2003b ). Inspired by the traceless Staudinger ligation reaction developed by Bertozzi, Raines, and coworkers for the conversion of an azide to an acyl amide, [9, 10] we perceived that the genetic Site-Selective Traceless Staudinger Ligation for Glycoprotein Synthesis Reveals Scope and Limitations GonÅalo J. L. Bernardes, Lars Linderoth, Katie J. Doores, Omar Boutureira, and Benjamin G. Davis*[a] Efficient, chemoselective reactions enable access to well-de-fined post-translationally modified proteins.[1–4] One approach Traceless Staudinger ligation of protected glycosyl azides. Here we report our initial results on the Staudinger ligation of unprotected α and β glucosyl azides with phosphines 2 . We were able to identify conditions that allowed a clean and stereoconservative reaction to occur in good to moderate yields, affording α or β glucosylamides Full Text A Photo‐Triggered Traceless Staudinger–Bertozzi Ligation Reaction by Hu, Peng and Feng, Tianshi and Yeung, Chi‐Chung and Koo, Chi‐Kin and Lau, Kai‐Chung and Lam, Michael H. W
Dec 01, 2008 · The traceless Staudinger ligation was designed by Raines and coworkers and Bertozzi and coworkers to generate a native peptide bond from an azide and a phosphine (Scheme 3II). Since its first disclosure, the traceless Staudinger reaction has been the subject of extensive studies to better understand the mechanism in order to optimize the
A detailed mechanism of the traceless Staudinger ligation is depicted in Scheme 2. In this mechanism, phosphinothioester 19 and azide 20 react to form phosphazide 21 (Step 1), which gives iminophosphorane 22 with concomitant release of N 2 (g) (Step 2). Abstract. Abstract The traceless Staudinger ligation of azides and phosphines is an effective method to produce an amide bond. In this work, density functional theory (DFT) calculations were carried out to investigate the mechanism of the traceless Staudinger ligation, which suggested that its rate-limiting step was the attack of azide on phosphine leading to the formation of phosphazide.
May 23, 2006 · This supports a 'ground-state destabilization' reaction mechanism for the first cleavage step in protein splicing. E., Armstrong, J.I. & Bertozzi, C.R.A. “Traceless” Staudinger ligation
Dec 25, 2014 · An azidonorleucine residue is installed at a desired site in a substrate protein by nonnatural amino acid incorporation, and a phosphinothioester is installed at the C terminus of a pendant protein by expressed protein ligation. Then, the traceless Staudinger ligation is used to link the substrate and pendant proteins via an isopeptide bond. Reaction mechanism and kinetics of the traceless Staudinger ligation MB Soellner, BL Nilsson, RT Raines Journal of the American Chemical Society 128 (27), 8820-8828 , 2006 Dec 05, 2014 · The DNA ligation reaction itself has two basic steps. Firstly the DNA ends have to collide by chance and stay together long enough for the ligase to join them. This is the most inefficient part of the reaction, but is easier at low temperatures. Jan 14, 2004 · Mechanistic studies by 31 P NMR spectroscopy identified the aza‐ylide 14 and the oxaphosphetane 15 as intermediates in the ligation reaction. 10 4 Scheme Preparation of the phosphane 10 and its application in the Staudinger ligation. 3.2. Traceless Staudinger Ligation Although the reaction detailed above works well in a biological environment Dec 21, 2011 · The traceless Staudinger amide-forming ligation, first reported in refs 53 and 54, involves the reaction of a peptidyl C-terminal phosphinothioester with a N-terminal peptide azide. This liberates Nov 26, 2012 · Redox catalysis: Aryl amides, imides, lactams, and dipeptides are obtained through a direct Staudinger ligation mediated by phosphine‐based redox catalysis (see scheme). Mechanistic studies indicate the involvement of a phosphonium carboxylate intermediate that leads to a 1,3‐acyl migration and thus results in C N bond formation. Project Methods The approach is to use ribonuclease A, the best characterized ribonuclease, as atemplate for the construction of hybrid proteins. Because RNase A lacks cytotoxic activity, any such activity in a hybrid protein would reveal a biochemical property necessary to cytotoxicity.