Yield: 34%

Spectra NMR <sup>1</sup>H (400 MHz, DMSO-d6, δ, ppm, J/Hz): 1.11 (3H, t, *J* = 7.45 Hz, CH2*CH3*), 1.94–2.03 (2H, m, *CH2*CH3), 3.22 (2H, *t*, *J* = 5.72 Hz, H-5), 3.87 (2H, t, *J* = 7.58 Hz, S*CH2*CH2), 4.12 (3H, s, OCH3), 5.01 (2H, *t*, *J* = 6.02 Hz, H-6), 6.19 (2H, s, OCH2O), 7.11 (1H, s, H-4), 7.82 (1H, s, H-1), 8.27 (1H, *d*, *J* = 9.33 Hz, H-12), 8.34 (1H, d, J = 9.33 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): 12.49 (CH2*CH3*), 17.17 (CH2*CH2*CH3), 26.16 (C-5), 53.27 (SCH2), 55.80 (C-6), 57.46 (OCH3), 102.18 (OCH2O), 105.60 (C-1), 108.42 (C-4), 120.14 (C-13b), 120.86 (C-13), 121.93 (C-8a), 126.37 (C-12), 127.98 (C-11), 130.96 (C-4a), 131.23 (C-12a), 133.33 (C-13a), 138.55 (C-9), 143.91 (C-8), 147.70 (C-2), 150.12 (C-3), 151.69 (C-10). Spectra IR (cm−<sup>1</sup> ): 817.71, 925.71, 1037.56, 1095.42, 1162.92, 1222.70, 1263.20, 1363.49, 1506.20, 1610.34, 1621.92, 3023.98, 3427.04. MS (ESI): *m*/*z* (M+) calcd for C22H22NO6S <sup>+</sup>, 428.116 found: 428.121.
