title: Synthesis of 2-amino-6-(4-[11C]methoxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester as a novel potential PET gene reporter probe for HBV and HSV-tk in cancers.
abstract: Acyclic nucleoside 2-amino-6-(4-methoxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester (ABE, 1) is a new hepatitis B virus (HBV) specific antiviral reagent and shows high anti-HBV activity. Carbon-11 labeled ABE may serve as a novel reporter probe for positron emission tomography (PET) to image HBV and herpes simplex virus thymidine kinase (HSV-tk) in cancers. The radiolabeling precursors 2-amino-6-(4-hydroxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester (10) and 2-N-Boc protected analogue 2-N-bis(Boc)amino-6-(4-hydroxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester (12), and the reference standard ABE were synthesized from bis(trifluoroethyl) (2-iodoethoxy)methylphosphonate (5), guanine (6), and 2-amino-6-chloropurine (8). The target radiotracer 2-amino-6-(4-[11C]methoxyphenylthio)-9-[2-(phosphonomethoxy)ethyl]purine bis(2,2,2-trifluoroethyl) ester ([11C]ABE, [11C]1) was prepared by O-[11C]methylation of the unprotected HO-precursor 10, or 2-N-Boc protected HO-precursor 12 with [11C]methyl triflate followed by a quick deprotection reaction, and isolated by solid-phase extraction (SPE) purification in 40-55% radiochemical yields.
authors.affiliation: Department of Radiology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
authors.forename: Ji-Quan
authors.initials: JQ
authors.lastname: Wang
authors.forename: Xiangshu
authors.initials: X
authors.lastname: Fei
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Gardner
authors.forename: Gary D
authors.initials: GD
authors.lastname: Hutchins
authors.forename: Qi-Huang
authors.initials: QH
authors.lastname: Zheng
mesh_terms: D000998:Antiviral Agents / Q000138:chemical synthesis; D002250:Carbon Radioisotopes; D017930:Genes, Reporter; D006515:Hepatitis B virus / Q000187:drug effects; D007553:Isotope Labeling; D008956:Models, Chemical; D015394:Molecular Structure; D049268:Positron-Emission Tomography; D011687:Purines / Q000138:chemical synthesis*; D018139:Simplexvirus / Q000201:enzymology; D013937:Thymidine Kinase / Q000235:genetics / Q000378:metabolism
chemical_list: C461207:2-amino-6-(4-methoxyphenylthio)-9-(2-(phosphonomethoxy)ethyl)purine bis(2,2,2-trifluoroethyl) ester; D000998:Antiviral Agents; D002250:Carbon Radioisotopes; D011687:Purines; D013937:Thymidine Kinase