Asymmetric Synthesis of L-[3-11C]Alanine.

Self Cite

107

In this review the recent progress in the development of suitable precursors for 11C‐labelling is discussed. Especially the last few years' advancement of the use of [11C] carbon monoxide as a versatile and useful precursor in labelling chemistry is presented. The development is set in perspective of its potential in applying molecular imaging tools in drug and tracer development.The possibility of exploring small tracer libraries utilizing the microdosing concept is explored. Copyright © 2007 John Wiley & Sons, Ltd.

Section: [ 11 C]precursors Used In Labellingmentioning

confidence: 99%

[¹¹C]Carbon monoxide, a versatile and useful precursor in labelling chemistry for PET‐ligand development

Långström

Itsenko

Rahman³

2007

Self Cite

107

“…63 The procedure was optimized by a chiral hydrogenation method resulting directly the corresponding L-isomers. 64 Halide derivatives were also used in alkylation reactions with chiral auxiliaries such as N-[(+)-2-hydroxypinanyl-3-idene]glycine tert-butyl ester, 65 or chiral nickel complexes, to obtain the [3-11 C]amino acids L- [3][4][5][6][7][8][9][10][11] 66 L-[3-11 C]alanine 66,67 and L-[3-11 C]dopa. 68,69 They also found application in chiral phase transfer reactions 70 for alkylation of imidazolidone derivatives 71 or simple glycine derivatives to form [3][4][5][6][7][8][9][10][11] [3][4][5][6][7][8][9][10][11] C]leucine and [3-11 C]phenylalanine.…”

Section: Enzymatic Methods (Route a Figure 1)mentioning

confidence: 99%

Methods for ¹¹C‐ and ¹⁸F‐labelling of amino acids and derivatives for positron emission tomography imaging

Neumaier

Coenen

2013

The different concepts realized for the synthesis of (11) C- and (18) F-labelled amino acids are summarized. Carbon-11 enables principally authentic radiolabelling of natural occurring amino acids by substituting one of the skeleton carbons by the radionuclide. Fluorine-18 is a foreign element for natural amino acids. Because of its advantageous nuclidic properties for positron emission tomography, however, it becomes increasingly important in molecular imaging, also with amino acid analogues. Especially in the last decade, considerable progress has been made with the radiosynthesis of (18) F-labelled amino acids that are now clinically approved, and thus assure their availability. In contrast, the synthetic possibilities with (11) C-labelled amino acids are more limited because of the short half-life of carbon-11 which also hampers their wide spread use.

“…The synthesis of l ‐[3‐ 11 C]alanine from [(+)‐2‐hydroxypinanyl‐3‐idene]glycine t ‐butyl ester and [ 11 C]methyl iodide was reported (Scheme ) …”

Section: Preparation and Labeling Of Endogenous Compoundsmentioning

confidence: 99%

“…77 The synthesis of L-[3-11 C]alanine from [(+)-2-hydroxypinanyl-3-idene]glycine t-butyl ester and [ 11 C]methyl iodide was reported (Scheme 14). 67 5-Hydroxy-L-tryptophan, the biosynthetic precursor of serotonin (5-HT), is decarboxylated to serotonin in the brain by the enzyme Laromatic amino acid decarboxylase (L-AADC). Multi-enzymatic syntheses of L-[b-11 C]tryptophan and 5-hydroxy-L-[b-11 C]tryptophan from racemic [3-11 C]alanine were reported (Schemes 2 and 15).…”

Section: Preparation and Labeling Of Endogenous Compounds Carbon-11mentioning

confidence: 99%

Endogenous compounds labeled with radionuclides of short half‐life—some perspectives

Långström¹,

Karimi

Watanabe

2013

In the article, the strategy and synthesis of some endogenous compounds labeled mainly with (11) C are presented. There are some examples illustrating how endogenous labeled compounds in connection with positron emission tomography have unique properties to describe various biological processes, and a few examples of the use of tracers labeled with (13) N and (15) O are also discussed. Labeled endogenous compounds may be an important asset to describe the conditions and the status of biological systems and might therefore be a key for the future search of individualized medicine.