Reaction Steps
4-chloro-N-{4-[(4-oxo-1-piperidinyl)sulfonyl]benzyl}benzamide 7d (500 mg, 1.23 mmol) was suspended in THF/methanol (10 ml/20 ml), N-hexylamine (149 mg, 1.48 mmol) and Cyanoborohydride-IRA400 (1.0 g, 3.0 mmol) were added and the reaction mixture was stirred at 50° C. overnight. Excess amine was scavenged with Ameba-PS (415 mg, 0.50 mmol) by shaking for 2 h. The resins were filtered off, solvent removed in vacuo and the obtained residue purified by column chromatography on silica gel using a step gradient of 2.5% methanol in DCM and 5% methanol in DCM. Fractions with Rf=0.28 (5% methanol in DCM, ) were collected and evaporated to dryness (Note: Up to 1% conc. NH3 (13.5 M) may be added during the chromatography to reduce loss of material). The residue was dissolved in DCM (10 ml) and 1 NHCl in ether (3 ml) added. After aging at room temp for 1 h the precipitate was filtered off and dried in vacuo. The hydrochloric salt of sulfonamide 4-chloro-N-(4-{[4-(hexylamino)-1-piperidinyl]sulfonyl}benzyl)benzamide 7 was isolated as off-white powder (260 mg, 36%) in >95% purity. M/Z APCI 492.0 (M+1), 490.2 (M−1). 1H-NMR (DMSO-d6) (HCl salt) δ 9.39 (t, 1H, H-N5, 3J=5.92 Hz), 8.97 (m, br, 2H, H-N16), 7.99 (d, 2H, 3J=8.65 Hz, H-C2,3), 7.75 (d, 2H, 3J=8.20 Hz, H-C8,9), 7.61 (m, 4H, H-C1,4,7,10), 4.61 (d, 2H, 3J=5.92 Hz, H-C6), 3.73* (d, 2H, 2J=11.84 Hz, Heq-C11,15), 3.07 (m, br, 1H, H-C13), 2.83 (m, br, 2H, H-C17), 2.29* (m, 2H, Hax-C12,14), 2.10* (d, br, 2H, 2J=11.90 Hz, Hax-C11,15), 1.71-1.54* (m, 4H, Heq-C12,14 and H-C18), 1.36-1.23 (m, 6H, H-C19,20,21), 0.89 (t, 3H, 3J=6.60 Hz, H-C22)