Synthesis of Some Pyrazolopyridine Sulphonamide Derivatives

Abstract

The diazonium salt of 3-aminopyrazolopyridine when treated with SO 2 and CuCl 2 produces the corresponding sulphonyl chloride. The sulphonyl chloride chloride easily reacts with hydrazine hydrate, ammonia, aromatic or heterocyclic amines to produce the corresponding sulphohydrazide, sulphonamide or N-sulphonamide derivatives. Sulphohydrazide reacts with acetylacetone to produce pyrazoly pyrazolopyridinyl sulphone which is also obtained by reaction of sulphonyl chloride with dimethylpyrazole. The aminopyrazolopyridine can be converte into pyrazolopyridinthiole by its reacting with ethyl dithioxanthate. The pyrazolopyridinthiole reacts with alkyl halides or acrylonitrile to produce S-alkylated derivatives.