White solid, 0.30 g (yield 31%); IR (KBr): 3468, 2935, 2860, 1730, 1664, 1493, 1456, 1402, 1372, 1310, 1290,
1201, 1168, 1110, 1015, 924, 846, 563 cm-1; 1H NMR (400 MHz, Chloroform-d) δ 6.47 (dd, J = 17.4, 11.0 Hz, 1H),
6.02 (s, 1H), 5.75 (d, J = 8.5 Hz, 1H), 5.34 (dd, J = 11.0, 1.5 Hz, 1H), 5.19 (dd, J = 17.4, 1.6 Hz, 1H), 4.16 – 4.02
(m, 2H), 3.99 – 3.79 (m, 2H), 3.35 (d, J = 6.5 Hz, 1H), 2.31 – 2.20 (m, 2H), 2.09 (d, J = 33.8 Hz, 4H), 1.76 (dd, J =
14.6, 3.1 Hz, 1H), 1.65 (d, J = 11.4 Hz, 2H), 1.45 (s, 4H), 1.34 (t, J = 7.1 Hz, 4H), 1.29 – 1.21 (m, 5H), 1.14 (s, 4H),
0.86 (d, J = 7.0 Hz, 3H), 0.74 (d, J = 7.0 Hz, 3H); 13C NMR (101 MHz, Chloroform-d) δ 215.8, 165.8, 160.9, 158.0,
137.9, 116.3, 107.3, 73.5, 69.1, 57.0, 44.4, 43.4, 42.9, 40.9, 38.6, 35.7, 35.0, 33.7, 33.4, 29.4, 28.7, 25.8, 25.3, 23.8,
22.6, 15.9, 13.8, 11.8, 10.4.; HRMS (ES) calcd [M + H]+ for C29H42N2O5S 531.2888, found 531.2884.
4.2.3.3. 14-O-[(4-Isopropoxy-6-methylpyrimidine-2-yl) thioacetyl] mutilin (6c)
White solid, 0.44 g (yield 45%); IR (KBr): 3448, 2925, 2864, 1733, 1676, 1500, 1452, 1413, 1376, 1362, 1297,
1263, 1176, 1116, 1058, 1019, 916, 731 cm-1; 1H NMR (400 MHz, Chloroform-d) δ 6.42 (dd, J = 17.4, 11.0 Hz,
1H), 5.87 (s, 1H), 5.67 (d, J = 8.5 Hz, 1H), 5.28 (dd, J = 11.0, 1.6 Hz, 1H), 5.13 (dd, J = 17.5, 1.6 Hz, 1H), 3.89 –
3.67 (m, 2H), 3.28 (d, J = 6.5 Hz, 1H), 2.24 – 2.15 (m, 2H), 2.02 (s, 3H), 1.97 – 1.89 (m, 1H), 1.69 (dd, J = 14.4,
3.1 Hz, 1H), 1.54 (dd, J = 6.7, 3.6 Hz, 6H), 1.38 (s, 7H), 1.18 (s, 4H), 1.08 (d, J = 7.0 Hz, 4H), 0.79 (dd, J = 6.9,
3.4 Hz, 3H), 0.66 (d, J = 7.0 Hz, 3H); 13C NMR (101 MHz, Chloroform-d) δ 215.9, 165.8, 159.9, 157.9, 137.9,
116.3, 73.5, 68.9, 57.0, 44.4, 43.3, 42.9, 40.9, 35.6, 34.9, 34.3, 33.4, 29.3, 28.7, 25.8, 25.3, 23.8, 22.2, 21.7, 18.2,
15.9, 13.8, 13.1, 10.4; HRMS (ES) calcd [M + H]+ for C30H44N2O5S 545.3009, found 545.3004.
4.2.3.4. 14-O-[(4-Butoxy-6-methylpyrimidine-2-yl) thioacetyl] mutilin (6d)
White solid, 0.24 g (yield 24%); IR (KBr): 3473, 2957, 2865, 1735, 1498, 1439, 1402, 1374, 1269, 1153, 1118,
1018, 981, 915, 839 cm-1; 1H NMR (400 MHz, Chloroform-d) δ 6.40 (dd, J = 17.4, 11.0 Hz, 1H), 5.94 (s, 1H), 5.68
(d, J = 8.5 Hz, 1H), 5.26 (dd, J = 11.0, 1.6 Hz, 1H), 5.12 (dd, J = 17.4, 1.6 Hz, 1H), 3.93 (td, J = 7.5, 5.6 Hz, 2H),
3.84 – 3.73 (m, 2H), 3.28 (d, J = 6.3 Hz, 1H), 2.24 – 2.15 (m, 2H), 2.06 (s, 4H), 1.98 (s, 2H), 1.62 (td, J = 14.6,
13.8, 9.5 Hz, 5H), 1.37 (d, J = 9.1 Hz, 8H), 1.21 – 1.14 (m, 3H), 1.07 (s, 3H), 0.90 (t, J = 7.4 Hz, 3H), 0.80 (d, J =
7.0 Hz, 3H), 0.67 (d, J = 7.0 Hz, 3H); 13C NMR (101 MHz, Chloroform-d) δ 215.9, 165.8, 160.9, 158.1, 137.9,
116.2, 107.2, 73.5, 69.0, 59.4, 57.0, 44.4, 43.4, 42.9, 40.8, 35.6, 35.0, 33.7, 33.4, 29.4, 28.6, 25.8, 25.4, 23.8, 22.6,
19.1, 15.8, 13.8, 13.2, 12.6, 10.4; HRMS (ES) calcd [M + H]+ for C31H46N2O5S 559.3122, found 559.3117.
4.2.3.5. 14-O-[(4-(2-aminoethoxy)-6-methylpyrimidine-2-yl) thioacetyl] mutilin (6e)
White solid, 036 g (yield 37%); IR (KBr): 3495, 3346, 2930, 2884, 1724, 1583, 1547, 1455, 1343, 1286, 1168,
1117, 1055, 1017, 980, 916, 736, 698 cm-1; 1H NMR (400 MHz, Chloroform-d) δ 6.48 (dd, J = 17.4, 11.0 Hz, 1H),
6.23 (s, 1H), 5.72 (d, J = 8.5 Hz, 1H), 5.30 (d, J = 2.9 Hz, 2H), 5.12 (d, J = 10.9 Hz, 3H), 4.39 (q, J = 5.9 Hz, 2H),