1-[(4-Chloro-3-sulfamoylbenzoyl)amino]-2,4,6-trimethylpyridinium salt is obtained in several ways from 4-chloro-3-sulfamoylbenzoyl hydrazide (I) or from 4-chloro-3-sulfamoylbenzoyl chloride (IV). The pyridinium salt thus produced may be converted by means of a base to besulpamide (I). 1) The first stage of the sequence is accomplished by refluxing the hydrazide (I) in ethanol with the pyrilium salt (II). 2) The Zincke salt (III) from 2,4,6-trimethylpyridine and 2,4-dinitrochlorobenzene is heated with the hydrazide (I) and triethylamine in ethanol. 3) 1-Amino-2,4,6-trimethylpyridinium salt (V) is acylated with 4-chloro-3-sulfamoylbenzoyl chloride (IV) and potassium carbonate in acetone.

1-[(4-Chloro-3-sulfamoylbenzoyl)amino]-2,4,6-trimethylpyridinium salt is obtained in several ways from 4-chloro-3-sulfamoylbenzoyl hydrazide (I) or from 4-chloro-3-sulfamoylbenzoyl chloride (IV). The pyridinium salt thus produced may be converted by means of a base to besulpamide (I). 1) The first stage of the sequence is accomplished by refluxing the hydrazide (I) in ethanol with the pyrilium salt (II). 2) The Zincke salt (III) from 2,4,6-trimethylpyridine and 2,4-dinitrochlorobenzene is heated with the hydrazide (I) and triethylamine in ethanol. 3) 1-Amino-2,4,6-trimethylpyridinium salt (V) is acylated with 4-chloro-3-sulfamoylbenzoyl chloride (IV) and potassium carbonate in acetone.