Showing papers by "Vadim A. Soloshonok published in 1995"

Fluorine-containing amino acids : synthesis and properties

Abstract: Partial table of contents: Syntheses of Fluorine-Containing Amino Acids by Methods of Classical Amino Acid Chemistry (V. Tolman). Preparation of Fluorine-Containing Amino Acids by Methods of Organofluorine Chemistry (V. Kukhar). Synthesis of Fluorine-Containing Amino Acids by Means of Homogeneous Catalysis (I. Ojima & Q. Dong). Synthesis of beta-Fluorine-Containing Amino Acids (N. Sewald & K. Burger). Asymmetric Synthesis of Fluorine-Containing Amino Acids (V. Kukhar, et. al). Enzymatic Synthesis of Fluorine-Containing Amino Acids (Y. Matsumura & M. Urushihara). Enzymatic Resolution of Racemic Fluorine-Containing Amino Acids (T. Miyazawa). High-Performance Liquid Chromatography of Fluorine-Containing Amino Acids (S. Galushko). Renin Inhibitors with Fluorine-Containing Amino Acid Derivatives (H. Sham). Index.

Biocatalytic approach to enantiomerically pure β-amino acids

Abstract: β-Aryl-β-amino acids were prepared in good chemical yield and high enantiomeric purity (>95% ee) via penicillin acylase-catalyzed hydrolysis of the corresponding N-phenylacetyl derivatives. The (R)-enantiomers were the fast-reacting isomers in all cases studied. The biocatalytic procedure described employs very simple set of reactions using inexpensive commercially available chemicals and enzyme, and could be easily scaled up.

Asymmetric aldol reactions of chiral Ni(II)-complex of glycine with aliphatic aldehydes. Stereodivergent synthesis of syn-(2S)- and syn-(2R)-β-alkylserines

Abstract: Stereoselectivity of aldol reactions between aliphatic aldehydes and Ni(II)-complex of chiral non-racemic Schiff base of glycine with ( S )- o -[ N -( N -benzylprolyl)amino]benzophenone (BPB) in the presence of excess of MeONa, has been studied as a function of time, reaction conditions and nature of an aldehyde. Two salient features of the reaction, very high pseudokinetic syn -(2 S )-diastereoselectivity, and dependence of thermodynamic syn -(2 R )-diastereoselectivity on the steric bulk of an aldehyde side chain, were disclosed and used for efficient (more than 90% de and ee) asymmetric synthesis of both syn -(2 S ) and syn -(2 R )-3-alkyl substituted serines. Synthetic potential and reliability of this asymmetric method are demonstrated with the large scale (2–20 g) preparation of enantiomerically pure amino acids.

Stereoselective Oxirane Formation by Reaction of Diazomethane on 1- Fluoro-3-((4-methylphenyl)sulfinyl)-3-phenylpropan-2-one.

Abstract: (2S, 2′R,RS)-2-(Fluoromethyl)-2-{[(4-methylphenyl)sulfinyl][phenyl]methyl}oxirane (4) was obtained in high chemical yield and with high diastereoselectivity by reacting diazomethane with pure (3R, ...