Asymmetric synthesis of fluorinated derivatives of aromatic and γ-branched amino acids via a chiral Ni(II) complex

• Maurizio Iannuzzi,
• Thomas Hohmann,
• Michael Dyrks,
• Kilian Haoues,
• Katarzyna Salamon-Krokosz and
• Beate Koksch

Beilstein J. Org. Chem. 2025, 21, 659–669, doi:10.3762/bjoc.21.52

• hectogram range, is a major strength of this method. In this context, Han et al. could show that the trifluorinated variant of α-aminobutyric acid, trifluoroethylglycine (TfeGly), can be synthesized on a 100 g scale with great enantiomeric purity [8]. The critical step here is the alkylation of the Ni(II

Position-dependent impact of hexafluoroleucine and trifluoroisoleucine on protease digestion

• Susanne Huhmann,
• Anne-Katrin Stegemann,
• Kristin Folmert,
• Damian Klemczak,
• Johann Moschner,
• Michelle Kube and
• Beate Koksch

Beilstein J. Org. Chem. 2017, 13, 2869–2882, doi:10.3762/bjoc.13.279

• ][40]. 2-Aminobutanoic acid (Abu) and its fluorinated analogues 2-amino-4,4-difluorobutanoic acid (DfeGly) and 2-amino-4,4,4-trifluorobutanoic acid (TfeGly) were individually incorporated at either the P2, the P1’ or the P2’ position [41] to give nine different analogues of FA. In prior studies, we

Chemical aminoacylation of tRNAs with fluorinated amino acids for in vitro protein mutagenesis

• Shijie Ye,
• Allison Ann Berger,
• Dominique Petzold,
• Oliver Reimann,
• Benjamin Matt and
• Beate Koksch

Beilstein J. Org. Chem. 2010, 6, No. 40, doi:10.3762/bjoc.6.40

• protein environment and to enable the design of fluorinated proteins with arbitrary desired properties. Keywords: chemical aminoacylation; DfeGly; fluorinated amino acids; site-specific protein mutagenesis; TfeGly; TfmAla; Introduction Over the past two decades, the interest in engineering proteins

• )-ethylglycine (Abu) and two of its fluorinated analogues, (S)-2-amino-4,4-difluorobutanoic acid (DfeGly) [23] and (S)-2-amino-4,4,4-trifluorobutanoic acid (TfeGly) [24], were synthesized in the appropriate protected activated form and used to chemically aminoacylate tRNAPheCUA by means of the hybrid

• acids were activated as their corresponding cyanomethyl esters (Scheme 1). The N-(4-pentenoyl) protection of Abu and its fluorinated analogues DfeGly and TfeGly, and the preparation of their cyanomethyl esters were performed as described by Hecht and co-workers [7][9]. In the first step, the amino acid