- α-Methylphenacyl thioesters as convenient thioacid precursors
-
α-Methylphenacyl (Mpa) thioesters are described as precursors of thioacids. Mpa thioesters are accessible via the condensation of carboxylic acids and phenacyl thiol, which is easily prepared without column chromatography. The Mpa thioesters are selectively deprotected by reduction with zinc dust in the presence of conventional thioacid protecting groups. In addition, the Mpa group exhibits orthogonal reactivity to the Boc group. These features are expected to facilitate the preparation of complex thioacids, including those in peptides.
- Hatanaka, Toru,Yuki, Ryosuke,Saito, Ryota,Sasaki, Kaname
-
supporting information
p. 10589 - 10592
(2016/11/30)
-
- Thioacetic acid/NaSH-mediated synthesis of N -protected amino thioacids and their utility in peptide synthesis
-
Thioacids are recently gaining momentum due to their versatile reactivity. The reactivity of thioacids has been widely explored in the selective amide/peptide bond formation. Thioacids are generally synthesized from the reaction between activated carboxylic acids such as acid chlorides, active esters, etc., and Na2S, H2S, or NaSH. We sought to investigate whether the versatile reactivity of the thioacids can be tuned for the conversion of carboxylic acids into corresponding thioacids in the presence of NaSH. Herein, we report that thioacetic acid- and NaSH-mediated synthesis of N-protected amino thioacids from the corresponding N-protected amino acids, oxidative dimerization of thioacids, crystal conformations of thioacid oxidative dimers, and the utility of thioacids and oxidative dimers in peptide synthesis. Our results suggest that peptides can be synthesized without using standard coupling agents.
- Mali, Sachitanand M.,Gopi, Hosahudya N.
-
p. 2377 - 2383
(2014/04/17)
-
- Processes for forming amide bonds and compositions related thereto
-
The disclosure relates to methods for producing amide bonds and reagents related thereto. In some embodiments, the disclosure relates to methods of producing an amide comprising mixing an O-silylated thionoester and an amine under conditions such that an amide is formed. In another embodiment, the disclosure relates to mixing a thiolacid, a silylating agent, and an amine under conditions such that an amide is formed.
- -
-
Page/Page column 21-24
(2015/01/07)
-
- T3P (propylphosphonic anhydride) mediated conversion of N α-protected amino/peptide acids into thioacids
-
A general, mild and an efficient protocol, which makes use of T3P as an acid activator for the synthesis of Nα-protected amino/peptide thioacids from corresponding acids in the presence of finely ground Na 2S as hydrosulfide ion donor is described. The protocol employed significantly increases the overall efficiency as the yield, reaction duration and purity of even sterically hindered amino acids.
- Madhu, Chilakapati,Basavaprabhu,Vishwanatha,Sureshbabu, Vommina V.
-
experimental part
p. 1406 - 1409
(2012/03/27)
-
- Synthesis, anti-HBV activity and renal cell toxicity evaluation of mixed phosphonate prodrugs of adefovir
-
A series of phosphonate ester prodrugs of adefovir incorporating l-amino (thio)acid and non-steroidal anti-inflammatory drug (NSAID) moieties were synthesized and their anti-HBV activity and renal cell toxicity were evaluated in HepG2 2.2.15 and HK-2 cell
- Fu, Xiao-Zhong,Ou, Yu,Pei, Jian-Ying,Liu, Ying,Li, Jing,Zhou, Wen,Lan, Yan-Yu,Wang, Ai-Min,Wang, Yong-Lin
-
scheme or table
p. 211 - 218
(2012/04/10)
-
- Fmoc-based synthesis of peptide thioacids for azide ligations via 2-cyanoethyl thioesters
-
Rapid and efficient preparation of peptide thioacids from 2-cyanoethyl peptide thioesters has been accomplished. S-2-Cyanoethyl peptide thioesters were obtained cleanly without the need for purification from resin-bound tert-butyl peptide thioesters using
- Raz, Richard,Rademann, J?rg
-
p. 5038 - 5041
(2013/01/15)
-
- In situ carboxyl activation using a silatropic switch: A new approach to amide and peptide constructions
-
The novel reactivity of O-silylthionoesters with amine nucleophiles to generate oxoamides (rather than thioamides) is described. A straightforward first-generation trimethylsilylation protocol using bistrimethylsilylacetamide (BSA) combined with the unique reactivity of the O-silylthionoesters toward 1° and 2° amines to generate oxoamides provides the simplest means of activating a thiol acid for peptide bond formation at neutral pH. Excellent stereoretention is observed.
- Wu, Wenting,Zhang, Zhihui,Liebeskind, Lanny S.
-
p. 14256 - 14259
(2011/11/05)
-
- Chemoselective peptidomimetic ligation using thioacid peptides and aziridine templates
-
Chemoselective peptidomimetic ligation has been made possible using thioacid peptides and NH aziridine-terminated amino acids and peptides. In the course of this reaction, a reduced amide bond is incorporated into the backbone of a peptide. This process e
- Assem, Naila,Natarajan, Aditya,Yudin, Andrei K.
-
supporting information; experimental part
p. 10986 - 10987
(2010/09/16)
-
- Design and synthesis of novel bis(l-amino acid) ester prodrugs of 9-[2-(phosphonomethoxy)ethyl]adenine (PMEA) with improved anti-HBV activity
-
A series of novel bis(l-amino acid) ester prodrugs of 9-[2-(phosphonomethoxy)ethyl] adenine (PMEA) was synthesized and their anti-HBV activity was evaluated in HepG 2 2.2.15 cells. Compounds 11, 12, 21, 22, 26, and 27 demonstrated more potent anti-HBV act
- Fu, Xiaozhong,Jiang, Saihong,Li, Chuan,Xin, Jian,Yang, Yushe,Ji, Ruyun
-
p. 465 - 470
(2007/10/03)
-
- Synthesis of chiral 3,4,5,6-tetrahydro-1,4-thiazin-2-ones (thiamorpholin-2-ones) - Novel heterocycles possessing enhanced carbonyl electrophilicity over their oxygen counterparts
-
We report herein the first synthesis of chiral derivatives possessing the 1,4-thiazinone core. As predicted, the thiolactone is more susceptible to nucleophilic attack than the equivalent lactone system. Georg Thieme Verlag Stuttgart.
- Drew, Michael G. B.,Harwood, Laurence M.,Yan, Ran
-
p. 3259 - 3262
(2008/09/17)
-
- Reductive Acylation of α-Keto Azides Derived from L-Amino Acids using N-Protected L-Aminothiocarboxylic S-Acids
-
Several homochiral N-protected α-aminothiocarboxylic S-acids have been synthesised from natural amino acids and used for reductive acylation of homochiral α,α'-amino keto azides, also derived from natural amino acids.
- McKervey, M. Anthony,O'Sullivan, Michael B.,Myers, Peter L.,Green, Richard H.
-
-
- Preparation of peptide thioacids using the Kaiser oxime resin
-
Peptide C-terminal thioacids are readily prepared with protecting groups intact by cleavage of peptides from Kaiser's oxime ester resin by treatment with hexamethyldisilathiane/tetrabutylammonium fluoride. Such thioacids are useful for peptide fragment co
- Schwabacher,Maynard
-
p. 1269 - 1270
(2007/10/02)
-