Purification of carbon-11 PET radiotracers from unlabeled precursors by preparative HPLC and SPE

Zheng

2016

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supporting

confidence: 80%

“…28,29 The chemical purity of the precursor and reference standard was >95%. The radiochemical purity of the target tracer was >99% determined by radio-HPLC through -ray (PIN diode) flow detector, and the chemical purity of the target tracer was >90% determined by reversed-phase HPLC through UV flow detector.…”

mentioning

confidence: 99%

Synthesis of [11C]MK-1064 as a new PET radioligand for imaging of orexin-2 receptor

Zheng

2016

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“…Likewise, the methods to minimize such wide range of SA from practice perspective have been provided in our previous works. 21 At the end of synthesis (EOS), the SA of [ 11 C]-tracer was determined again by analytical HPLC, 22 calculated, decay corrected to EOB, and based on [ 11 C]CO2, which was in agreement with the 'on line' determined value. In each our [ 11 C]-tracer production, if semi-preparative HPLC was used for purification, then the SA of [ 11 C]-tracer was assessed by both semi-preparative HPLC (during synthesis) and analytical HPLC (EOS); if SPE was used for purification, then the SA of [ 11 C]-tracer was only measured by analytical HPLC at EOS.…”

mentioning

confidence: 61%

“…11 Chemical purity and radiochemical purity were determined by analytical HPLC. 22 The chemical purity of the precursor and reference standard was >90%. The radiochemical purity of the target tracer was >99% determined by radio-HPLC through γ-ray (PIN diode) flow detector, and the chemical purity of the target tracer was >90% determined by reversed-phase HPLC through UV flow detector.…”

mentioning

confidence: 99%

Synthesis and preliminary biological evaluation of [11C]methyl (2-amino-5-(benzylthio)thiazolo[4,5-d]pyrimidin-7-yl)-d-leucinate for the fractalkine receptor (CX3CR1)

Meyer

et al. 2017

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Abstract-TheCX3C chemokine receptor 1 (CX3CR1), also known as fractalkine receptor or G-protein coupled receptor 13 (GPR13), is a protein in humans. 1 CX3CR1 binds the chemokine CX3CL1, also called fractalkine ligand or neurotactin. 2 CX3CR1 is expressed in the brain, spleen, and in subpopulations of leukocytes, cells of monocytic lineage, and neutrophils but also in lymphocytes, and associated with various cancer, cardiovascular and neurological diseases such as Alzheimer's disease (AD) and Parkinson's disease (PD). 3 CX3CR1 is an interesting therapeutic target, and many selective CX3CR1 antagonists have been developed. 4,5 Methyl (2-amino-5-(benzylthio)thiazolo[4,5-d]pyrimidin-7-yl)-Dleucinate (5) recently developed by AstraZeneca is a potent and selective CX3CR1 antagonist with Ki 8.3 and 1940 nM for CX3CR1 and CXCR2, respectively, and selectivity index (SI) 230. 6 CX3CR1 has also become a promising target for molecular imaging of CX3CR1-mediated diseases and image-guided therapy using positron emission tomography (PET) modality. However, radionuclides including carbon-11 and fluorine-18 labeled CX3CR1 antagonists are still not reported. In our previous work, we have developed carbon-11-labeled naphthalene-sulfonamides as potential radioligands for PET imaging of chemokine receptor 8 (CCR8), as indicated in Figure 1. 7 In this ongoing study, we first target CX3CR1 and develop radiolabeled CX3CR1 antagonists. Here we report the synthesis and preliminary biological evaluation of

“…25 Chemical purity and radiochemical purity were determined by analytical HPLC. 38 The chemical purity of the precursor 5 and reference standard 4a was >93%. The radiochemical purity of the target tracer [ 11 C]4a was >99% determined by radio-HPLC through γ-ray (PIN diode) flow detector, and the chemical purity of [ 11 C]4a was >90% determined by RP HPLC through UV flow detector.…”

mentioning

confidence: 99%

Synthesis of [11C]CX-6258 as a new PET tracer for imaging of Pim kinases in cancer

Tzintzun

et al. 2015

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Abstract-Thereference standard CX-6258 {(E)-5-chloro-3-((5-(3-(4-methyl-1,4-diazepane-1-carbonyl)phenyl)furan-2-yl)methylene)indolin-2-one, 4a} and its desmethylated precursor N-desmethyl-CX-6258 {(E)-3-((5-(3-(1,4-diazepane-1-carbonyl)phenyl)furan-2-yl)methylene)-5-chloroindolin-2-one, 5} for radiolabeling were synthesized from 5-bromo-2-furaldehyde and 3-carboxybenzeneboronic acid in 3 and 4 steps with 29-49% and 24-32% overall chemical yield, respectively. The target tracer 11 C]CO2 and decay corrected to end of bombardment (EOB) with 370-1110 GBq/µmol specific activity at EOB.