Potassium Carbonate → HCID 58107404, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-benzenesulfonyl-8-(4-chloro-3-sulfamoyl-benzoyl)-1,3,4,5-tetrahydro-pyrido[4,3-b]indole-2-carboxylic acid ethyl ester and 5-benzenesulfonyl-7-(4-chloro-3-sulfamoyl-benzoyl)-1,3,4,5-tetrahydro-pyrido[4,3-b]indole-2-carboxylic acid ethyl ester (1 g) is dissolved in 5 mL of tetrahydrofuran-methanol-water (10:10:1) and treated with 0.344 g of potassium carbonate. The reaction mixture is heated at 140° C. for 15 min (microwave irradiation), filtered and concentrated. The residue is purified on reverse phase HPLC to give pure 8-(4-chloro-3-sulfamoyl-benzoyl)-1,3,4,5-tetrahydro-pyrido[4,3-b]indole-2-carboxylic acid ethyl ester MS (m/z): 462 (M+1); and 7-(4-chloro-3-sulfamoyl-benzoyl)-1,3,4,5-tetrahydro-pyrido[4,3-b]indole-2-carboxylic acid ethyl ester MS (m/z): 462 (M+1); both as yellow syrups. Both isomers are separated by HPLC (Chiracel OD-H 250-4.6 mm, flow 1 ml/Min, UV 235 nM, gradient hexane-ethanol 70-30). The retention times are 6.91 min for 8-(4-chloro-3-sulfamoyl-benzoyl)-1,3,4,5-tetrahydro-pyrido[4,3-b]indole-2-carboxylic acid ethyl ester and 10.20 min for 7-(4-chloro-3-sulfamoyl-benzoyl)-1,3,4,5-tetrahydro-pyrido[4,3-b]indole-2-carboxylic acid ethyl ester.

Provenance & Evidence