Related Experiment Video
Updated: Jun 3, 2026
07:07
Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology
Published on: March 12, 2015
New F-18 prosthetic group via oxime coupling
Patrick Carberry1, Brian P Lieberman, Karl Ploessl
1Department of Radiology, University of Pennsylvania , 3700 Market Street, Room 305, Philadelphia, Pennsylvania 19104, United States.
Bioconjugate Chemistry
|April 2, 2011
Summary
A new fluorine-18 prosthetic ligand was synthesized for radiolabeling. This method allows for efficient labeling of molecules, potentially aiding in the development of new imaging agents for amyloid plaques.
Area of Science:
- Radiochemistry
- Organic synthesis
- Nuclear medicine
Background:
- Development of novel radiotracers is crucial for molecular imaging.
- Fluorine-18 (18F) is a widely used positron-emitting isotope for PET imaging.
- Prosthetic groups facilitate the incorporation of 18F into biomolecules.
Purpose of the Study:
- To synthesize and characterize a novel 18F-labeled prosthetic ligand.
- To evaluate the utility of this ligand for labeling potential PET imaging agents for β-amyloid plaques.
- To assess the biodistribution of the labeled compounds in mice.
Main Methods:
- Synthesis of the novel fluorine-18 prosthetic ligand, 5-(1,3-dioxolan-2-yl)-2-(2-(2-(2-fluoroethoxy)ethoxy)ethoxy)pyridine [(18)F]2.
- Labeling of target molecules containing an aminooxy functional group via oxime bond formation.
- Preparation of two potential imaging agents, [(18)F]23 and [(18)F]24.
- Biodistribution studies in male ICR mice.
Main Results:
- The prosthetic ligand [(18)F]2 was synthesized in high radiochemical yield (71%) and purity (99%) within 10 minutes.
- Two oxime-labeled compounds, [(18)F]23 and [(18)F]24, were prepared as potential β-amyloid plaque imaging agents.
- Biodistribution studies showed varied brain uptake and suggested potential in vivo decomposition for [(18)F]24.
Conclusions:
- A novel, efficiently synthesized 18F prosthetic ligand was developed.
- This ligand enables labeling of molecules via chemoselective oxime coupling.
- The approach holds promise for developing new PET imaging agents, particularly for amyloid plaques.
Related Concept Videos
01:29Preparation of Amines: Reduction of Oximes and Nitro Compounds
Oximes can be reduced to primary amines using catalytic hydrogenation, hydride reduction, or sodium metal reduction. The reduction of aliphatic and aromatic nitro compounds to primary amines takes place by either catalytic hydrogenation or by using active metals like Fe, Zn, and Sn in the presence of an acid.
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
02:36Oxymercuration-Reduction of Alkenes
Oxymercuration–reduction of alkenes is one of the major reactions converting alkenes to alcohols. It involves the hydration of alkenes with mercuric acetate in a mixture of tetrahydrofuran and water, forming an organomercury adduct. This is followed by a demercuration step in which the adduct is reduced to an alcohol using sodium borohydride.
02:01Alkynes to Carboxylic Acids: Oxidative Cleavage
Alkynes undergo oxidative cleavage in the presence of oxidizing reagents like potassium permanganate and ozone. The triple bond — one σ bond and two π bonds — is completely cleaved, and the alkyne is oxidized to carboxylic acids. When warm and basic aqueous potassium permanganate is used as an oxidizing agent, alkynes are first converted to carboxylate salts via an unstable α-diketone intermediate. Further, a mild acid treatment protonates the carboxylate anions generating free carboxylic acid...
01:46Oxidative Cleavage of Alkenes: Ozonolysis
In ozonolysis, ozone is used to cleave a carbon–carbon double bond to form aldehydes and ketones, or carboxylic acids, depending on the work-up.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
Ozone is a symmetrical bent molecule stabilized by a resonance structure.
01:19α-Hydroxy Ketones via Reductive Coupling of Esters: Acyloin Condensation Overview
The pinacol and McMurry reactions involve the reductive coupling of ketones or aldehydes. Similarly, the bimolecular reductive coupling of two ester molecules in the presence of sodium metal in an aprotic solvent yields an α-hydroxy ketone product. The α-hydroxy ketone is also called acyloin, so the reaction is referred to as ‘acyloin condensation.’
02:24Acid-Catalyzed Ring-Opening of Epoxides
Epoxides that are three-membered ring systems are more reactive than other cyclic and acyclic ethers. The high reactivity of epoxides originates from the strain present in the ring. This ring strain acts as a driving force for epoxides to undergo ring-opening reactions either with halogen acids or weak nucleophiles in the presence of mild acid. The acid catalyst converts the epoxide oxygen, a poor leaving group, into an oxonium ion, a better leaving group, making the reaction feasible. The...