126686-69-9Relevant articles and documents
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
, p. 246 - 251 (2017)
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.
Highly Cytotoxic Bioconjugated Gold(I) Complexes with Cysteine-Containing Dipeptides
Gutiérrez, Alejandro,Marzo, Isabel,Cativiela, Carlos,Laguna, Antonio,Gimeno, M. Concepci?n
supporting information, p. 11088 - 11095 (2015/11/10)
Several gold(I) complexes with cysteine-containing dipeptides have been prepared starting from cystine by coupling different amino acids and using several orthogonal protections. The first step is the reaction of cystine, where the sulfur centre is protected as disulfide, with Boc2O in order to protect the amino group, followed by coupling of an amino acid ester; finally the disulfide bridge is broken with mercaptoethanol to afford the dipeptide derivative. Further reaction with [AuCl(PPh3)] gives the gold-dipeptide-phosphine species. Starting from these formally gold(I) thiolate-dipeptide phosphine complexes with the general formula [Au(SR)(PR3)] different structural modifications, such as change in the type of the amino protecting group, the type of phosphine, the number of gold(I) atoms per molecule, or the use of a non-proteinogenic conformationally restricted amino acid ester, were introduced in order to evaluate their influence in the biological activity of the final complexes. The cytotoxic activity, in vitro, of these complexes was evaluated against different tumour human cell lines (A549, MiaPaca2 and Jurkat). The complexes show an outstanding cytotoxic activity with IC50 values in the very low micromolar range. Structure-activity relationship studies from the complexes open the possibility of designing more potent and promising gold(I) anticancer agents. Striking with gold: Gold(I) complexes with cysteine-containing dipeptides were prepared starting from cystine by coupling different amino acids, and using several orthogonal protections. The complexes show excellent cytotoxic activity with IC50 values in the very low micromolar range. The structural changes in the parent compound led to the synthesis of the most effective compound in the cell lines tested, which is the complex with two AuPPh3+ fragments coordinated to the Boc-Cys-Gly-OMe peptide (see scheme).
Synthesis of Boc-Cys-Ala-OMe and its stereoselective addition to α-methylene-γ-butyrolactones
Talaga,Schaeffer,Mattes,Benezra,Stampf
, p. 5029 - 5038 (2007/10/02)
-
