» Articles » PMID: 35517533

Deuteration Ethylation - Strategies to Improve the Metabolic Fate of an F-labeled Celecoxib Derivative

Abstract

The inducible isoenzyme cyclooxygenase-2 (COX-2) is closely associated with chemo-/radioresistance and poor prognosis of solid tumors. Therefore, COX-2 represents an attractive target for functional characterization of tumors by positron emission tomography (PET). In this study, the celecoxib derivative 3-([F]fluoromethyl)-1-[4-(methylsulfonyl)phenyl]-5-(-tolyl)-1-pyrazole ([F]5a) was chosen as a lead compound having a reported high COX-2 inhibitory potency and a potentially low carbonic anhydrase binding tendency. The respective deuterated analog [D,F]5a and the fluoroethyl-substituted derivative [F]5b were selected to study the influence of these modifications with respect to COX inhibition potency and metabolic stability of the radiolabeled tracers . COX-2 inhibitory potency was found to be influenced by elongation of the side chain but, as expected, not by deuteration. An automated radiosynthesis comprising F-fluorination and purification under comparable conditions provided the radiotracers [F]5a,b and [D,F]5a in good radiochemical yields (RCY) and high radiochemical purity (RCP). Biodistribution and PET studies comparing all three compounds revealed bone accumulation of F-activity to be lowest for the ethyl derivative [F]5b. However, the deuterated analog [D,F]5a turned out to be the most stable compound of the three derivatives studied here. Time-dependent degradation of [F]5a,b and [D,F]5a after incubation in murine liver microsomes was in accordance with the data on metabolism . Furthermore, metabolites were identified based on UPLC-MS/MS.

Citing Articles

Preclinical evaluation of an F-labeled N-acryloyllysine piperazide for covalent targeting of transglutaminase 2.

Wodtke R, Laube M, Hauser S, Meister S, Ludwig F, Fischer S EJNMMI Radiopharm Chem. 2024; 9(1):1.

PMID: 38165538 PMC: 10761660. DOI: 10.1186/s41181-023-00231-1.


Preparation of F-Labeled Tracers Targeting Fibroblast Activation Protein via Sulfur [F]Fluoride Exchange Reaction.

Craig A, Kogler J, Laube M, Ullrich M, Donat C, Wodtke R Pharmaceutics. 2023; 15(12).

PMID: 38140090 PMC: 10747913. DOI: 10.3390/pharmaceutics15122749.


Investigation of Radiotracer Metabolic Stability In Vitro with CYP-Overexpressing Hepatoma Cell Lines.

Lemm S, Kohler S, Wodtke R, Jung F, Kupper J, Pietzsch J Cells. 2022; 11(15).

PMID: 35954291 PMC: 9368227. DOI: 10.3390/cells11152447.


Fluorine-18 Labelled Radioligands for PET Imaging of Cyclooxygenase-2.

Kaur J, Bhardwaj A, Wuest F Molecules. 2022; 27(12).

PMID: 35744851 PMC: 9227202. DOI: 10.3390/molecules27123722.


Modulation of γ-Secretase Activity by a Carborane-Based Flurbiprofen Analogue.

Saretz S, Basset G, Useini L, Laube M, Pietzsch J, Draca D Molecules. 2021; 26(10).

PMID: 34064783 PMC: 8151329. DOI: 10.3390/molecules26102843.

References
1.
Tsukada H, Sato K, Fukumoto D, Kakiuchi T . Evaluation of D-isomers of O-18F-fluoromethyl, O-18F-fluoroethyl and O-18F-fluoropropyl tyrosine as tumour imaging agents in mice. Eur J Nucl Med Mol Imaging. 2006; 33(9):1017-24. DOI: 10.1007/s00259-006-0076-8. View

2.
Tietz O, Marshall A, Wuest M, Wang M, Wuest F . Radiotracers for molecular imaging of cyclooxygenase-2 (COX-2) enzyme. Curr Med Chem. 2013; 20(35):4350-69. DOI: 10.2174/09298673113206660260. View

3.
Hawkey C . COX-2 chronology. Gut. 2005; 54(11):1509-14. PMC: 1774747. DOI: 10.1136/gut.2005.065003. View

4.
Knudsen J, Carlsson U, Hammarstrom P, Sokol G, Cantilena L . The cyclooxygenase-2 inhibitor celecoxib is a potent inhibitor of human carbonic anhydrase II. Inflammation. 2005; 28(5):285-90. DOI: 10.1007/s10753-004-6052-1. View

5.
Lebedev A, Jiao J, Lee J, Yang F, Allison N, Herschman H . Radiochemistry on electrodes: Synthesis of an 18F-labelled and in vivo stable COX-2 inhibitor. PLoS One. 2017; 12(5):e0176606. PMC: 5413030. DOI: 10.1371/journal.pone.0176606. View