Reaction Steps
colorless amorphous solid; [α]D22−158.2 (c 0.5, MeOH); UV (MeOH) λmax nm (ε) 205 (19500), 247 (12700); IR (KBr) νmax 3447, 2972, 2927, 1737, 1690, 1450, 1252, 1181, 936 cm−1; 1H NMR (CDCl3, 400 MHz) δ 6.93 (1H, s, H-19), 6.48 (1H, bs, H-17), 5.48 (1H, ddd, J=10.7, 6.2, 6.2 Hz, H-12), 5.39 (1H, m, H-13), 5.37 (1H, m, H-9), 5.34 (1H, dd, J=8.0, 2.3 Hz, H-15), 4.29 (1H, dd, J=6.0, 2.6 Hz, H-7), 4.09 (1H, ddd, J=10.8, 7.1, 2.9 Hz, H-3), 3.59 (1H, d, J=7.1 Hz, 3-OH), 3.17 (1H, dq, J=6.0, 6.9 Hz, H-6), 2.68 (3H, s, H-21), 2.54 (1H, ddd, J=15.2, 8.1, 8.0 Hz, H-14a), 2.44 (1H, bs, 7-OH), 2.42 (1H, dd, J=15.1, 2.9 Hz, H-2a), 2.41 (1H, ddd, J=15.2, 2.3, 2.3 Hz, H-14b), 2.34 (1H, dd, J=15.1, 10.8 Hz, H-2b), 2.20 (1H, m, H-10a), 2.18 (2H, m, H-11), 2.12 (1H, m, H-10b), 2.06 (3H, bs, H-27), 1.67 (3H, bs, H-25), 1.27 (3H, s, H-23), 1.21 (3H, d, J=6.9 Hz, H-24), 1.15 (3H, s, H-22); 13C NMR, see Table 1; EIMS m/z 475 [M]+ (6), 392 (7), 304 (6), 288 (33), 204 (76), 171 (19), 168 (100), 164 (12); HREIMS m/z 475.2380 (calcd. for C26H37NO5S, 475.2392).