Reaction Steps
Acetyl chloride (0.020 ml, 0.243 mmol) was added to a solution of 2-butyl-5-phenyl-4-(1,2,3,4-tetrahydroisoquinolin-6-ylamino)isothiazol-3(2H)-one 1,1-dioxide (example 60) (0.100 g, 0.243 mmol) and TEA (0.040 mmol, 0.267 mmol) in dry THF (2 ml) and the reaction mixture was stirred at rt for 40 mins. EtOAc was added and the mixture was washed with brine and evaporated. The residue was purified by silica gel column chromatography using a 1:5 mixture of EtOAc/petroleum ether 40-60° C. mixture as eluent, to give the title compound (0.071 g, 64%). 1H NMR (500 MHz CDCl3); δ 7.30-7.22 (m, 2H), 7.22-7.14 (m, 4H), 6.88, 6.68 (dd, 1H), 6.68 (td, 1H), 6.36, 6.31 (d, 1H), 4.58, 4.47 (s, 2H), 3.79 (t, 2H), 3.63, 3.48 (t, 2H), 2.43, 2.39 (t, 2H), 2.16, 2.15 (s, 3H), 1.94-1.84 (m, 2H), 1.56-1.44 (m, 2H), 1.01 (t, 3H); 13C NMR (125 MHz CDCl3): δ 169.8, 159.6, 135.8, 134.4, 131.0, 130.8, 129.6, 129.4, 128.3, 127.0, 126.2, 126.0, 122.6, 122.2, 120.4, 120.0, 111.4, 111.2, 47.8, 43.9, 40.5, 39.4, 30.5, 29.3, 26.8, 22.0, 21.8, 20.3, 13.8; Mass Spectrum M+H+ 454.
