52.4% |
With dmap; dicyclohexyl-carbodiimide; In N,N-dimethyl-formamide; at 20℃; for 24.0h; |
To a 100-ml flask, DMXAA (0.339 g, 1.2 mmol), DCC (0.248 g,1.2 mmol) and DMAP (15 mg, 0.12 mmol) were dissolved in 30 mldried DMF. Compound P-1 (0.354 g, 1.0 mmol) in 10 ml dried DMF was then added dropwise with stirring. The reactionwas lasted at r.t. for 24 h. After the finish of reaction, the mixture was pulled into50 ml ice-water with violently stirring for 20 min. The precipitates were collected by filtrate, and were purified by flash column liquidchromatography led to white powder 0.324 g, yield 52.4%, purity 97.4%. Mp: 205-206 C; 1H NMR (DMSO-d6, 500 MHz) delta: 8.01-8.04(m, 3H, H-1, 70, 90), 6.85-6.87 (m, 3H, H-3, 8, 100), 6.73-6.75 (m, 2H,H-50, 80), 6.28-6.31 (m, 1H, H-2), 6.21-6.24 (m, 1H, H-7), 4.00-4.03(m, 2H, H-500), 3.98 (m, 2H, H-300), 3.71 (s, 2H, H-100), 3.34-3.36 (m,2H, H-400), 2.76-2.79 (m, 2H, H-40), 2.62-2.64 (m, 2H, H-30),1.78-1.81 (s, 6H, 5,6-CH3), 1.41-1.44 (s, 6H, 20-CH3); 13C NMR(DMSO-d6, 125 MHz) delta: 181.36 (C-9), 179.08 (C-6'), 176.54 (C-2"),166.76 (C-11a'), 164.13 (C-4b), 161.70 (C-10a'), 158.32 (C-3), 156.63(C-4a), 151.97 (C-9'), 136.51 (C-4), 135.63 (C-6), 134.17 (C-12a'),129.89 (C-12'), 128.48 (C-8), 127.48 (C-10'), 126.45 (C-8'), 125.63 (C-9'), 125.45 (C-7), 124.63 (C-4a'), 124.19 (C-5'), 123.39 (C-7'), 122.09(C-5a'),121.23 (C-8a),118.20 (C-2),104.48 (C-6a'), 98.03 (C-5), 93.83(C-8b), 79.88 (C-2'), 68.93 (C-5"), 64.24 (C-3"), 34.07 (C-"), 33.98(C-3'), 32.85 (C-4'), 28.32 (C-4"), 25.17 (2 x 2'-CH3), 18.65 (6-CH3),16.43 (5-CH3); MS-ESI m/z: 619.23 [MH]; HRMS (m/z): calc. for[C38H34O8+H]+ 619.2332, found 619.2338. |