1207955-07-4

Upstream product

• 93617-83-5 [18F]-tetrabutylammonium fluoride 
• 1246467-94-6 N,N,N-trimethyl-3-((2,3,5,6-tetrafluorophenoxy)-carbonyl)pyridin-6-aminium trifluoromethanesulfonate 
• 6311-35-9 6-bromonicotinic acid 
• 5326-23-8 6-Chloro-3-pyridinecarboxylic acid 
• 1246467-93-5 N,N,N-trimethyl-5-((2,3,5,6-tetrafluorophenoxy)carbonyl)pyridine-2-aminium chloride 
• 769-39-1 2,3,5,6-tetraflourophenol 
• 5006-66-6 6-hydroxy-3-pyridinecarboxylic acid 
• 1207954-98-0 6-chloronicotinic acid 2,3,5,6-tetrafluorophenyl ester 

Downstream Products

• 1207955-08-5 C₅₆H₈₁⁽¹⁸⁾FN₁₆O₁₈S₃ 

Relevant academic research and scientific papers

Fluorine-18-Labeled Antibody Ligands for PET Imaging of Amyloid-β in Brain

Antibodies are attractive as radioligands due to their outstanding specificity and high affinity, but their inability to cross the blood-brain barrier (BBB) limits their use for CNS targets. To enhance brain distribution, amyloid-β (Aβ) antibodies were fused to a transferrin receptor (TfR) antibody fragment, enabling receptor mediated transport across the BBB. The aim of this study was to label these bispecific antibodies with fluorine-18 and use them for Aβ PET imaging. Bispecific antibody ligands RmAb158-scFv8D3 and Tribody A2, both targeting Aβ and TfR, were functionalized with trans-cyclooctene (TCO) groups and conjugated with 18F-labeled tetrazines through an inverse electron demand Diels-Alder reaction performed at ambient temperature. 18F-labeling did not affect antibody binding in vitro, and initial brain uptake was high. Conjugates with the first tetrazine variant ([18F]T1) displayed high uptake in bone, indicating extensive defluorination, a problem that was resolved with the second and third tetrazine variants ([18F]T2 and [18F]T3). Although the antibody ligands' half-life in blood was too long to optimally match the physical half-life of fluorine-18 (t1/2 = 110 min), [18F]T3-Tribody A2 PET seemed to discriminate transgenic mice (tg-ArcSwe) with Aβ deposits from wild-type mice 12 h after injection. This study demonstrates that 18F-labeling of bispecific, brain penetrating antibodies is feasible and, with further optimization, could be used for CNS PET imaging.

Rapid 18F-radiolabeling of peptides from [18F]fluoride using a single microfluidics device

To date the majority of 18F-peptide radiolabeling approaches are multi-step, low yielding and time-consuming processes. Given the short half-life of 18F (109.8 min), it is critical that methods are developed to increase the efficiency of this process with simpler, higher yielding and faster reactions that can be rapidly translated into clinical use. Here, we demonstrate the first microfluidic synthesis of the [18F]F-Py-TFP prosthetic group with radiochemical yields of up to 97% and a synthesis time of 3 min. In addition, we utilized a single microfluidics device to prepare the [18F]F-Py-YGGFL peptide using [18F]F-Py-TFP, from [18F]fluoride in a two-step, fully automated approach. The model peptide NH2-YGGFL was radiolabeled with [18F]F-Py-TFP in up to 28% overall radiochemical yield within 8 minutes starting from anhydrous [18F]fluoride. This journal is

Fast indirect fluorine-18 labeling of protein/peptide using the useful 6-fluoronicotinic acid-2,3,5,6-tetrafluorophenyl prosthetic group: A method comparable to direct fluorination

Fluorine-18 labeling of biomolecules is mostly performed by an indirect labeling method using a prosthetic group. Fluorine-18 labeled 6-fluoronicotinic acid-2,3,5,6-tetrafluorophenyl ester is a useful prosthetic group to radiolabel a protein. Recently, we reported an improved preparation of this prosthetic group. To test the conjugation efficiency of the labeled ester prepared by this method, we have performed conjugation reactions with a peptide, a protein, and a small molecule. Prostate-specific membrane antigen targeting small molecule [18F]DCFPyL, αvβ3 integrin receptors targeting peptide [18F]c(RGDfK) and [18F]albumin were prepared in good radiochemical yields. The conjugation reactions were completed at 40°C to 50°C in 10?minutes. The overall radiochemical yield was 25% to 43% in 30 to 45?minutes.

Fluorine-18 labeled aldehydes as prosthetic groups for oxime coupling with a FVIIa protein

18F-labeled aldehydes can be utilized for oxime coupling with chemically sensitive proteins, such as coagulation factor VII (FVII), if they are sufficiently reactive and can react in an aqueous solvent. New 18F-labeled nonvolatile aldehyde prosthetic groups derived from [18F]F-Py-TFP and spirocyclic iodonium (III)ylide precursors for late stage 18F-labeling were developed. These precursors were characterized, 18F-labeled, and compared in reactivity for oxime coupling. Oxime coupling was performed on an amino-oxy modified inhibited factor VII (FVIIai-ONH2) in low concentration to prove the applicability of the proposed method.

FIBRIN-BINDING COMPOUNDS FOR IMAGING AND TREATMENT

This disclosure relates to compounds of Formula IV: for fibrin imaging, wherein the compounds comprise an imaging or therapeutic radioisotope.

Focal adhesion kinase (FAK)-targeting compound and preparation method and application thereof

An embodiment of the invention provides an FAK-targeting compound as well as a preparation method and application of the compound. The compound has a structure as shown in a general formula (I) whichis described in the specification. The compound provided

Original synthesis of radiolabeling precursors for batch and on resin one-step/late-stage radiofluorination of peptides

Radiolabeling of peptides with fluorine-18 is hurdled by their chemical sensitivity and complicated processes. Original triflyl-pyridine intermediates afforded ammonium precursors that were radiolabeled at low temperature. From that study, a generic tag h

Development of PSMA-1007-Related Series of 18F-Labeled Glu-Ureido-Type PSMA Inhibitors

In recent years, a number of drugs targeting the prostate-specific membrane antigen (PSMA) have become important tools in the diagnosis and treatment of prostate cancer. In the present work, we report on the synthesis and preclinical evaluation of a series of 18F-labeled PSMA ligands for diagnostic application based on the theragnostic ligand PSMA-617. By applying modifications to the linker structure, insight into the structure-activity relationship could be gained, highlighting the importance of hydrophilicity and stereoselectivity on interaction with PSMA and hence the biodistribution. Selected compounds were co-crystallized with the PSMA protein and analyzed by X-rays with mixed results. Among these, PSMA-1007 (compound 5) showed the best interaction with the PSMA protein. The respective radiotracer [18F]PSMA-1007 was translated into the clinic and is, in the meantime, subject of advanced clinical trials.

4-Nitrophenyl activated esters are superior synthons for indirect radiofluorination of biomolecules

Indirect radiolabelling has for a long time been the mainstay strategy for radiofluorination of biomolecules. Acylation of biomolecules through the use of an 18F-labelled activated ester is a standard method for indirect radiolabelling. However, the preparation of 18F-labelled activated esters is typically a complex and multistep procedure. Herein, we describe the use of 4-nitrophenyl (PNP) activated esters to rapidly prepare 18F-labelled acylation synthons in one step. Furthermore, we present a comparative study of PNP activated esters and the commonly utilised 2,3,5,6-tetrafluorphenyl (TFP) activated esters under direct radiofluorination conditions and demonstrate their relative acylation behaviour. We demonstrate the superiority of PNP esters under direct radiofluorination conditions with favourable acylation kinetics.

Labeling Single Domain Antibody Fragments with Fluorine-18 Using 2,3,5,6-Tetrafluorophenyl 6-[18F]Fluoronicotinate Resulting in High Tumor-to-Kidney Ratios

ImmunoPET agents are being investigated to assess the status of epidermal growth factor receptor 2 (HER2) in breast cancer patients with the goal of selecting those likely to benefit from HER2-targeted therapies and monitoring their progress after these t