Synthesis and stability of sulfur-35 labelled 4-ethylbicyclothiophosphate

Article abstract of DOI:10.1007/BF02252166

Different synthetic routes to the preparation of 4-ethyl-2,6,7-trioxa-1-phosphabicyclo[2,2,2]octane-1-thioxide labelled with sulfur-35 have been investigated since it is of considerable interest as radioligand for neurochemistry. The thiophosphate was successfully synthesized by sulfuration of the corresponding bicyclophosphite by elemental sulfur-3 5, however the radiochemical purity of the material obtained in this way proves to be low. Convenient methods for synthesis of the thioxide from [³⁵S] thiourea, based on the results of the autoradiolysis of the starting [³⁵S] thiourea, has been discovered giving rise to thioxide with high radiochemical purity. The autoradiolytic stability of the labelled thiophosphate has been studied. 1999 KluwerAcademic/Plenum Publishers.