149117-03-3Relevant academic research and scientific papers
Stereospecific syntheses of all four stereoisomers of 4-fluoroglutamic acid
Hudlicky, M.
, p. 193 - 210 (1993)
(+)-L-threo-4-fluoroglutamic acid . (-)-D-threo-4-Fluoroglutamic acid was prepared analogously from trans-4-hydroxy-D-proline, obtained from its diastereomer by inversion of configuration at carbon 4 of the pyrrolidine ring using the diethyl azodicarboxylate-triphenylphosphine procedure. cis-4-Hydroxy-L-proline, necessary for the synthesis of (+)-L-erythro-4-fluoroglutamic acid , was prepared from trans-4-hydroxy-L-proline by benzyloxycarbonylation at the nitrogen, oxidation of the 1-benzyloxycarbonyl-trans-4-hydroxy-L-proline to 1-benzyloxycarbonyl-4-oxo-L-proline, its reduction to 1-benzyloxycarbonyl-cis-4-hydroxy-L-proline and deprotection of the latter at the nitrogen. (-)-cis-4-Fluoro-L-proline and (+)-trans-4-fluoro-D-proline were isolated after the hydrolysis of incompletely oxidized methyl 1-acetyl-cis-4-fluoro-L-prolinate and methyl 1-acetyl-trans-4-fluoro-D-prolinate, respectively.
Chemistry of 4-fluoroglutamic acid. Part 2. Separation of the diastereomers on a large scale. Preparation of cis- and trans-4-fluoro-5-pyrrolidone-2-carboxylic acids (4-fluoropyroglutamic acids)
Tolman, V.,Vlasakova, V.,Nemecek, J.
, p. 185 - 191 (1993)
Separation of the 4-fluoroglutamic acid diastereomers has been achieved by crystalization of the hydrochlorides of their dialkyl esters 1b and 2d.Subsesquent hydrolysis afforded the diastereomers 1a and 2a in 100percent steric purity.Conversion of the acids into the 5-methyl esters followed by treatment with ammonia gives rise to the trans and cis isomers of 4-fluoro-5-pyrrolidine-2-carboxylic acid, 3 and 4.NMR data are given.
Chemistry of 4-fluoroglutamic acid. Part 1. A critical survey of its syntheses: an attempt to optimize reaction conditions for large-scale preparation
Tolman, V.
, p. 179 - 183 (1993)
Synthetic methods for the preparation of 4-fluoroglutamic acid (1) are reviewed.The utility of every method for routine laboratory work is evaluated with respect to the accessibility of starting materials and reagents, the overall yields and also from the viewpoint of safety.Optimum reaction conditions are given for the selected pathway, suitable for large-scale synthesis.
[F-18]-labeled L-glutamic acid, [F-18]-labeled L-glutamine, derivatives thereof and use thereof and processes for their preparation
-
Page/Page column 37; 38, (2016/08/03)
The compounds and the synthesis of [F-18]-labeled L-glutamic acid, [F-18]-labeled L-glutamate, their derivatives as set forth in formula (I) and their uses are described.
[F-18]-LABELED L-GLUTAMIC ACID, [F-18]-LABELED L-GLUTAMINE, DERIVATIVES THEREOF AND USE THEREOF AND PROCESSES FOR THEIR PREPARATION
-
Paragraph 0890, (2016/12/01)
The compounds and the synthesis of [F-18]-labeled L-glutamic acid, [F-18]-labeled L-glutamate, their derivatives as set forth in formula (I) and their uses are described.
[F-18]-LABELED L-GLUTAMIC ACID, [F-18]-LABELED L-GLUTAMINE, DERIVATIVES THEREOF AND USE THEREOF AND PROCESSES FOR THEIR PREPARATION
-
, (2010/09/05)
The compounds and the synthesis of [F-18]-labeled L-glutamic acid, [F-18]-labeled L-glutamate, their derivatives as set forth in formula (I) and their uses are described.
Electrophilic fluorination of pyroglutamic acid derivatives: Application of substrate-dependent reactivity and diastereoselectivity to the synthesis of optically active 4-fluoroglutamic acids
Konas,Coward
, p. 8831 - 8842 (2007/10/03)
Electrophilic fluorination of enantiomerically pure 2-pyrrolidinones (4) derived from (L)-glutamic acid has been investigated as a method for the synthesis of single stereoisomers of 4-fluorinated glutamic acids. Reaction of the lactam enolate derived from 9 with NFSi results in a completely diastereoselective monofluorination reaction to yield the monocyclic trans-substituted α-fluoro lactam product 21. Unfortunately, a decreased kinetic acidity in 21 and other structurally related monofluorinated products renders them resistant to a second fluorination. In contrast, the bicyclic lactam 12 is readily difluorinated under the standard conditions described to yield the α,α-difluoro lactam 24. The difference in reactivity between the two types of related lactams is attributed mainly to the presence or lack of a steric interaction between the base used for deprotonation and the protecting group present in the pyrrolidinone substrates. This conclusion was reached based on analysis of the X-ray crystal structure of 21, molecular modeling, and experimental evidence. The key intermediates 21 and 24 are converted to (2S,4R)-4-fluoroglutamic acid and (2S)-4,4-difluoroglutamic acid, respectively.
Chemistry of 4-fluoroglutamic acid. Part 3. Preparation of the diastereomers of 4-fluoroglutamine and 4-fluoroisoglutamine. An enzymatic access to the antipodes of 4-amino-2-fluorobutyric acid
Tolman, Vladimír,Sedmera, Petr
, p. 5 - 10 (2007/10/03)
The pure diastereomers of 4-fluoroglutamine and 4-fluoroisoglutamine were prepared from the corresponding 4-fluoroglutamic acids. Glutamic decarboxylase treatment of the acids led to chiral 2-fluoroGABA.
Practical synthesis of L-erythro- and L-threo-4-fluoroglutamic acids using aminoacylase
Kokuryo, Yoshitsugu,Nakatani, Takuji,Kobayashi, Kobee,Tamura, Yoshinori,Kawada, Kenji,Ohtani, Mitsuaki
, p. 3545 - 3551 (2007/10/03)
Enantiomerically pure L-erythro- and L-threo-4-fluoroglutamic acids 1a and 1b were conveniently prepared. The key steps in this synthesis relied upon separation of diastereomers of N-chloroacetyl-4-fluoroglutamic acid 5-methyl ester 7 by recrystallization and enzymatic resolution of enantiomers of the resulting 7(a+c) and 7(b+d) by aminoacylase. Protection of the γ-carboxyl group as a methyl ester was found to be crucial for this enzymatic reaction.
