SYNTHESIS AND STABILITY OF SULFUR-35 LABELLED 4-ETHYLBICYCLOTHIOPHOSPHATE

Abstract

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-35, 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.

Authors: S. E. Tkachenko, T. P. Trofimova, and V. M. Fedoseev.

English Translation in Chemistry of Heterocyclic Compounds, 1999, 35 (8), pp 973-977

http://link.springer.com/article/10.1007/BF02252166