2448-45-5Relevant articles and documents
Chemical dynamic kinetic resolution and S/R interconversion of unprotected α-amino acids
Takeda, Ryosuke,Kawamura, Akie,Kawashima, Aki,Sato, Tatsunori,Moriwaki, Hiroki,Izawa, Kunisuke,Akaji, Kenichi,Wang, Shuni,Liu, Hong,Ace?a, José Luis,Soloshonok, Vadim A.
, p. 12214 - 12217 (2014)
Reported herein is the first purely chemical method for the dynamic kinetic resolution (DKR) of unprotected racemic α-amino acids (α-AAs), a method which can rival the economic efficiency of the enzymatic reactions. The DKR reaction principle can be readily applied for S/R interconversions of α-AAs, the methodological versatility of which is unmatched by biocatalytic approaches. The presented process features a virtually complete stereochemical outcome, fully recyclable source of chirality, and operationally simple and convenient reaction conditions, thus allowing its ready scalability. A quite unique and novel mode of the thermodynamic control over the stereochemical outcome, including an exciting interplay between axial, helical, and central elements of chirality is proposed. A new player for DKR: Dynamic kinetic resolution of α-amino acids has been achieved upon complexation with nickel(II) and a chiral ligand derived from optically active bis(naphthyl)amine under thermodynamic control, thus affording excellent diastereoselectivities and chemical yields. The S to R interconversion of α-amino acids is also described.
Tricyclic compound as plasma kallikrein inhibitor and application thereof
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, (2021/06/23)
The invention provides a tricyclic plasma kallikrein inhibitor compound which is novel in structure, good in activity and high in selectivity. The tricyclic plasma kallikrein inhibitor compound can be widely applied to prevention or treatment of diseases related to plasma kallikrein activity.
Enantioselective inclusion of pyrene-1-sulfonate salts of α-amino acids with crystals of α-cyclodextrin
Hattori, Tetsutaro,Kitamoto, Yuichi,Maeda, Tetsuya,Miyoshi, Ikuko,Morohashi, Naoya
, (2020/04/01)
Enantioselective inclusion of α-amino acids with crystals of α-cyclodextrin (α-CD) has been achieved by converting the amino acids into sulfonate salts with pyrene-1-sulfonic acid (PyS). For example, crystals of α-CD selectively include L-leucine/PyS (1:1) salt in a host/guest ratio of ~1 with 92%ee from a solution of the racemic salt in ethanol/N-methylformamide (91:9) at 40 °C. Under conditions optimized for individual amino acids, the PyS salts of valine, phenylalanine, and methionine are also included with good enantioselectivities (up to 86%ee). Mechanistic studies for the inclusion of leucine/PyS salt reveals that the enantioselectivity originates from the difference in stability between the inclusion complexes of D- and L-leucine/PyS salts with α-CD in crystals.