Solution and solid-phase synthesis of trifluoromethyl peptides and mimetics

Catalytic asymmetric synthesis of quaternary trifluoromethyl α- to ε-amino acid derivatives via umpolung allylation/2-aza-Cope rearrangement

In this study, we developed an efficient Ir-catalyzed cascade umpolung allylation/2-aza-Cope rearrangement of tertiary α-trifluoromethyl α-amino acid derivatives for the preparation of a variety of quaternary α-trifluoromethyl α-amino acids in high yields with excellent enantioselectivities. The umpolung reactivity empowered by the activation of the key isatin-ketoimine moiety obviates the intractable enantioselectivity control in Pd-catalyzed asymmetric linear α-allylation. In combination with quasi parallel kinetic resolution or kinetic resolution, the generality of this method is further demonstrated by the first preparation of enantioenriched quaternary trifluoromethyl β-, γ-, δ- and ε-amino acid derivatives.

Organic base-catalyzed stereodivergent synthesis of (R)- and (S)-3-amino-4,4,4-trifluorobutanoic acids

Organic base-catalyzed reaction of (S)-N-tert-butanesulfinyl (3,3,3)-trifluoroacetaldimine with dialkyl malonates was found to be effective for synthesis of both (S,S(S)) and (R,S(S)) β-aminomalonates in high yield with good to excellent diastereoselectivity (76-98% de). The products of this Mannich reaction provide direct access to β-trifluoromethyl-β-alanine of either (R) or (S) absolute configuration.

Platinum-Based Antitumor Drugs Containing Enantiomerically Pure α-Trifluoromethyl Alanine as Ligand

Synthetic amino acids such as fluorinated alpha-amino acids are currently actively investigated for their biological activity. Herein, we report on the synthesis and characterization of platinum complexes containing an N,O-chelated pure enantiomer of alpha-trifluoromethylalanine (alpha-Tfm-Ala). The compounds are either anionic, K[PtCl2(alpha-Tfm-Ala)], or cationic, [PtAm2(alpha-Tfm-Ala)](NO3) (Am2= (NH3)2, ethylendiamine (en), 1,10-phenanthroline (phen), and 2,9-dimethyl-1,10-phenanthroline (Me2phen)). All complexes are highly soluble in water and have been fully characterized by NMR spectroscopy. In vitro cytotoxicity assays on different human tumor cell lines have been performed on some of the isolated compounds. [Pt(NH3)2(alpha-Tfm-Ala)] with R configuration of the amino acid proved to have an activity comparable to that of the reference compound cisplatin. Flow cytometric analysis on NCI-H460 tumor cells (absence of G2/M arrest, which instead is observed in the case of cisplatin) suggests a mechanism of action different from that of cisplatin.

A Convenient Enantioselective Synthesis of (S)-α-Trifluoromethylisoserine

[reaction: see text] This report describes two straightforward synthetic methodologies to obtain alpha-CF3-isoserine, a new alpha,alpha-disubstituted beta-amino acid, from alpha-(trifluoromethyl)acrylic acid. The routes involve the synthesis of five-membered cyclic sulfates (using sulfuryl chloride) or sulfamidates (using the Burgess reagent) from the corresponding chiral diols, which are obtained by a catalytic asymmetric dihydroxylation (AD) reaction.

Reliable high-throughput functional screening with 3-FABS

An NMR method called 3-FABS has extended the capabilities of NMR, enabling rapid, efficient and reliable high-throughput functional screening for the identification of inhibitors and for measuring their 50% mean inhibition concentration (IC(50)) with accuracy. The substrate is tagged with a CF(3) moiety and (19)F NMR spectroscopy is used for the detection of the substrate and product components. We provide comprehensive insight into 3-FABS, a discussion of its strength and weakness when compared with other HTS techniques and a presentation of some of its applications to the screening of different enzymes and to multiple screening.