Tautomérie du 2,5-dimercapto-1,3,4-thiadiazole et synthèse de thiadiazoloacridiniques

Abstract

Some 2(3H)-thione-5-alkylthio-1,3,4-thiadiazoles were prepared with a view to arylating these compounds with 9-chloroacridines. Using pyridine as solvent and base, this arylation led to the 2-thione-(N)3-acridinyl-5-alkylthio-1,3,4-thiadiazoles. Molecular structures of the latter were determined either by NMR spectroscopy or by referring to X-ray crystallography of the 5-(diethylaminoethylthio)-1,3,4-thiadiazole-2-thione. Thus, with respect to the tautomeric equilibrium of the compound investigated, the thione group was detected either in the solid state or in solution. In contrast, 2-acridinylthio-5-alkylthio-1,3,4-thiadiazoles were prepared by using the sodium salt of 2-mercapto-5-alkylthio-1,3,4-thiadiazoles as starting material. Keywords: acridines, thiadiazoles, tautomerism.