5-(4-dimethylcarbamoylmethylphenylsulfonyl)thiophene-2-sulfonamide (1.35 g) was dissolved in 30 ml of tetrahydrofuran under a nitrogen atmosphere. Borane tetrahydrofuran complex (8 ml of 1 molar solution) was added and the mixture was stirred at room temperature for 3 hours. Hydrochloric acid (20 ml of 6N) was then added cautiously and the mixture was heated on a steam bath, boiling off tetrahydrofuran. The acidic solution was cooled to room temperature and extracted with chloroform. The aqueous phase was separated and its pH adjusted to pH 8.5 before extracting it with ethyl acetate. The ethyl acetate phase was dried over sodium sulfate and concentrated under vacuum to give a residue of an oily solid. This was chromatographed on silica gel to give a pure product, m.p. 169°-172° C. N.M.R. (DMSO, d6) δ: 2.17 (6H, s), 2.50 (2H, T, J=6 Hz), 2.82 (2H, T, J=6 Hz), 7.55 (2H, d, J=9 Hz), 7.60 (1H, d, J=4 Hz), 7.87 (1H, d, J=4 Hz), 7.94 (2H, d, J=9 Hz), 8.04 (2H, broad s). Anal Calc'd for C14H18N2O4S3 : C, 44.90; H, 4.84; N, 7.48. Found: C, 44.54; H, 4.89; N, 7.60. The following compounds where also made by similar procedures: 5-[4-(2-ethylaminoethyl)phenylsulfonyl]thiophene-2-sulfonamide (m.p. 174-177). 5-[4-(3-methylaminopropyl)phenylsulfonyl]thiophene-2-sulfonmide (m.p. 178°-179.5° C.), 5-[4-(3-dimethylaminopropyl)phenylsulfonyl]thiophene-2-sulfonamide (m.p. 163°-164.5° C.), and 5-[4-(4-dimethylaminobutyl)phenylsulfonyl]thiophene-2-sulfonamide (m.p. 186°-189° C.).
