Yield: 25%

Spectra NMR <sup>1</sup>H (400 MHz, DMSO-d6, δ, ppm, *J*/Hz): 1.52 (3H, *t*, *J* = 7.32 Hz, CH2*CH3*), 3.22 (2H, *t*, *J* = 6.05 Hz, H-5), 3.89 (2H, q, J<sup>1</sup> = 3.50 Hz, J<sup>2</sup> = 10.96 Hz, *CH2*CH3), 4.12 (3H, s, OCH3), 5.01 (2H, t, *J* = 5.91 Hz, H-6), 6.18 (2H, s, OCH2O), 7.11 (1H, s, H-4), 7.82 (1H, s, H–1), 8.27 (1H, *d*, *J* = 9.48 Hz, H-12), 8.34 (1H, *d*, *J* = 9.48 Hz, H-11), 9.10 (1H, s, H-13), 9.64 (1H, s, H–8). Spectra NMR <sup>13</sup>C (100 MHz, DMSO-d6, δ, ppm): 8.18 (CH2*CH3*), 26.19 (C-5), 47.00 (SCH2), 55.83 (C–6), 57.44 (OCH3), 102.20 (OCH2O), 105.61 (C-1), 108.45 (C–4), 120.18 (C-13b), 120.90 (C-13), 121.98 (C-8a), 126.42 (C-12), 128.02 (C-11), 131.02 (C-4a), 131.27 (C-12a), 133.36 (C-13a), 138.63 (C-9), 143.91 (C-8), 147.75 (C-2), 150.17 (C-3), 151.71 (C-10). Spectra IR (cm−<sup>1</sup> ): 806.14, 923.78, 1033.71, 1097.35, 1164.85, 1222.70, 1278.2063, 1363.49, 1506.20, 1608.42, 1621.92, 3023.98, 3423.19, 3629.54. MS (ESI): *m*/*z* (M+) calcd for C21H20NO6S <sup>+</sup>, 414.101 found: 414.096.

3.1.5. 10-Methoxy-2,3-methylenedioxy-9-((propane-1-sulfonyl)oxy)protoberberine chloride (**10c**)
