5429-56-1Relevant articles and documents
Ivanov et al.
, p. 504,507,509 (1963)
Tailored Approaches towards the Synthesis of l-S-(Trifluoromethyl)cysteine- and l-Trifluoromethionine-Containing Peptides
Gadais, Charlène,Saraiva-Rosa, Nathalie,Chelain, Evelyne,Pytkowicz, Julien,Brigaud, Thierry
supporting information, p. 246 - 251 (2017/01/24)
Among the fluorinated noncanonical amino acids, l-trifluoromethionine (TFM) and l-S-(trifluoromethyl)cysteine (TfmCys), fluorinated analogues of methionine and cysteine, are of particular interest because of their ability to locally increase the hydrophobicity of peptides. We report herein the synthesis of tert-butoxycarbonyl/benzyl-protected TFM and TfmCys by using a cheap and user-friendly radical trifluoromethylation approach. The benzyl protecting group of these fluorinated amino acids could be conveniently removed by hydrogenolysis, which circumvented troublesome saponification reactions. For the first time, TfmCys was inserted into a peptide sequence by liquid- or solid-phase peptide synthesis. Finally, a late trifluoromethylation strategy with the use of Togni's reagent on disulfide-bridged peptides was also efficient to incorporate TFM or TfmCys at both N-terminal and internal positions.
First RAFT polymerization of captodative 2-acetamidoacrylic acid (AAA) monomer: An experimental and theoretical study
Dedeo?lu, Burcu,U?ur, Ilke,De?irmenci, Isa,Aviyente, Viktorya,Bar?in, Bilin?,?ayli, G?khan,Acar, Havva Yagci
, p. 5122 - 5132 (2013/09/02)
A capto-dative monomer, 2-acetamidoacrylic acid (AAA), was homopolymerized through RAFT polymerization method using 2-(2-cyanopropanyl dithiobenzoate) (CPDB) as a chain transfer agent and AIBN free radical initiator in DMF at 70 C. DFT calculations were performed in the selection of the CTA for this unique monomer as well as to elucidate the influence of cd-stabilized growing radical on the kinetic parameters in comparison to methacrylic acid (MAA) and N-(prop-1-en-2-yl)acetamide (NPAA), which represent the captive and dative groups of AAA, respectively. Keq for these three monomers is in the order of AAA β > k-add for NPAA and MAA, for AAA k-add is about four orders of magnitude larger than kβ. This is the major disadvantage in the RAFT process of AAA using CPDB. Yet, poly(AAA) could be achieved with PDI as low as 1.49. Molecular weight of the polymer can be tuned by the monomer/AIBN ratio. First block copolymers of AAA with MAA and MMA using poly(AAA) as a macro-CTA were also synthesized, indicating the presence of active chain ends.
