反応手順
A similar procedure (Schwartz, E. et al. Macromolecules 2011, 44, 4735-4741) to that previously described for the preparation of 347 was followed using 2 (1.50 g, 2.70 mmol), 4-acetamidocinnamic acid (0.50 g, 2.46 mmol), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (1.04 g, 5.60 mmol), triethylamine (1.24 mL, 8.91 mmol) and dimethylaminopyridine (60 mg, 0.49 mmol) in dichloromethane (25 mL), at room temperature for 72 h. Purification by flash chromatography (hexane/ethyl acetate 1:4) afforded 337 as a white solid (2.0 g, 2.69 mmol, 99%). mp 125-130° C.; 1H NMR (300 MHz, CDCl3) δ 2.17 (3H, s, NHAc), 3.35-3.90 (4.16H, m, NCH2CH2O, H-2, H-3, W/H-4), 3.83-3.95 (0.84H, m, U/H-1, V/H-1, Y/H-4), 4.14 (0.14H, m, U/H-4), 4.28-4.38 (2.32H, m, NCH2CH2O, V/H-4), 4.43-4.47 (0.54H, m, W/H-1, Y/H-1), 5.53 (0.32H, dd, J=3.4 and 1.2 Hz, V/H-6), 5.55 (0.38H, dd, J=3.4 and 1.2 Hz, Y/H-6), 5.59 (s, OH), 5.60 (s, OH), 5.63 (s, OH), 5.69 (s, OH), 6.06 (0.14H, dd, J=3.4 and 1.2 Hz, U/H-6), 6.06 (0.16H, dd, J=3.4 and 1.2 Hz, W/H-6), 6.17 (0.30H, d, J=15.8 Hz, COCH═CH), 6.26 (0.70H, d, J=15.8 Hz, COCH═CH), 6.74-7.61 (21H, m, Ar and COCH═CH), 8.40-8.63 (2H, m, αPyr); m/z (ESI, 70 eV) 765 (MNa+, 100%); (Found MNa+ 765.2684, C46H38N4NaO6 requires 765.2687).
