title: A new SiF-Dipropargyl glycerol scaffold as a versatile prosthetic group to design dimeric radioligands: synthesis of the [(18) F]BMPPSiF tracer to image serotonin receptors.
abstract: A novel SiX-dipropargyl glycerol scaffold (X: H, F, or (18) F) was developed as a versatile prosthetic group that provides technical advantages for the preparation of dimeric radioligands based on silicon fluoride acceptor pre- or post-labeling with fluorine-18. Rapid conjugation with the prosthetic group takes place in microwave-assisted click conjugation under mild conditions. Thus, a bivalent homodimeric SiX-dipropargyl glycerol derivatized radioligand, [(18) F]BMPPSiF, with enhanced affinity was developed by using click conjugation. High uptake of the radioligand was demonstrated in 5-HT1A receptor-rich regions in the brain with positron emission tomography. Molecular docking studies (rigid protein-flexible ligand) of BMPPSiF and known antagonists (WAY-100635, MPPF, and MefWAY) with monomeric, dimeric, and multimeric 5-HT1A receptor models were performed, with the highest G score obtained for docked BMPPSiF: -6.766 as compared with all three antagonists on the monomeric model. Multimeric induced-fit docking was also performed to visualize the comparable mode of binding under in vivo conditions, and a notably improved G score of -8.455 was observed for BMPPSiF. These data directly correlate the high binding potential of BMPPSiF with the bivalent binding mode obtained in the biological studies. The present study warrants wide application of the SiX-dipropargyl glycerol prosthetic group in the development of ligands for imaging with enhanced affinity markers for specific targeting based on peptides, nucleosides, and lipids.
authors.affiliation: Division of Cyclotron and Radiopharamceutical Sciences, Brig. SK Mazumdar Road, Delhi 110054 (India).
authors.forename: Puja Panwar
authors.initials: PP
authors.lastname: Hazari
authors.forename: Jurgen
authors.initials: J
authors.lastname: Schulz
authors.forename: Delphine
authors.initials: D
authors.lastname: Vimont
authors.forename: Nidhi
authors.initials: N
authors.lastname: Chadha
authors.forename: Michele
authors.initials: M
authors.lastname: Allard
authors.forename: Magali
authors.initials: M
authors.lastname: Szlosek-Pinaud
authors.forename: Eric
authors.initials: E
authors.lastname: Fouquet
authors.forename: Anil Kumar
authors.initials: AK
authors.lastname: Mishra
mesh_terms: D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging* / Q000378:metabolism; D001923:Brain Chemistry; D019281:Dimerization; D005462:Fluorine Radioisotopes / Q000032:analysis* / Q000378:metabolism; D005990:Glycerol / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000378:metabolism; D008024:Ligands; D062105:Molecular Docking Simulation; D017646:Organosilicon Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism; D049268:Positron-Emission Tomography; D051381:Rats; D017207:Rats, Sprague-Dawley; D044282:Receptor, Serotonin, 5-HT1A / Q000032:analysis* / Q000378:metabolism
chemical_list: D005462:Fluorine Radioisotopes; D008024:Ligands; D017646:Organosilicon Compounds; D044282:Receptor, Serotonin, 5-HT1A; D005990:Glycerol
keywords: click chemistry; fluorides; ligand design; radiolabeling; silicon