The esterification of 4-phenoxy-3-nitro-5-sulfamoylbenzoic acid (I) with methanol and H2SO4 gives the corresponding methyl ester (II), which is reduced with H2 over Raney-Ni in methanol yielding methyl 4-phenoxy-3-amino-5-sulfamoylbenzoate (III). The condensation of (III) with succinic anhydride (B) or succinoyl chloride (A) by means of pyridine in refluxing dioxane affords methyl 4-phenoxy-3N-succinimido-5-sulfamoylbenzoate (IV), which is reduced with borontrifluoride ethearate and NaBH4 in diglyme giving methyl 4-phenoxy-3-(1-pyrrolidinyl)-5-sulfamoylbenzoate (V). Finally, this compound is hydrolyzed with NaOH in water.

The esterification of 4-phenoxy-3-nitro-5-sulfamoylbenzoic acid (I) with methanol and H2SO4 gives the corresponding methyl ester (II), which is reduced with H2 over Raney-Ni in methanol yielding methyl 4-phenoxy-3-amino-5-sulfamoylbenzoate (III). The condensation of (III) with succinic anhydride (B) or succinoyl chloride (A) by means of pyridine in refluxing dioxane affords methyl 4-phenoxy-3N-succinimido-5-sulfamoylbenzoate (IV), which is reduced with borontrifluoride ethearate and NaBH4 in diglyme giving methyl 4-phenoxy-3-(1-pyrrolidinyl)-5-sulfamoylbenzoate (V). Finally, this compound is hydrolyzed with NaOH in water.

The esterification of 4-phenoxy-3-nitro-5-sulfamoylbenzoic acid (I) with methanol and H2SO4 gives the corresponding methyl ester (II), which is reduced with H2 over Raney-Ni in methanol yielding methyl 4-phenoxy-3-amino-5-sulfamoylbenzoate (III). The condensation of (III) with succinic anhydride (B) or succinoyl chloride (A) by means of pyridine in refluxing dioxane affords methyl 4-phenoxy-3N-succinimido-5-sulfamoylbenzoate (IV), which is reduced with borontrifluoride ethearate and NaBH4 in diglyme giving methyl 4-phenoxy-3-(1-pyrrolidinyl)-5-sulfamoylbenzoate (V). Finally, this compound is hydrolyzed with NaOH in water.