反应详情

To a 50-mL round bottom flask loaded with tri-tert-butyl 2,2′,2″-(10-(6-(2-(4-hydroxyphenyl)acetyl)-2,8,11-trioxo-12-oxa-3,6,9-triazatetradecyl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetate 2 (0.260 g, 0.291 mmol) was added LiOH.H2O (0.018 g, 0.437 mmol, 1.5 eq.), 6 mL of EtOH, and 2 mL of H2O. The reaction was stirred at room temperature for 12 hours. After solvent removal in vacuo, purification was achieved by preparative reverse-phase HPLC (gradient from 100% 0.1% formic acid in water to 50% 0.1% formic acid in water/50% CH3CN) to give 3. 65.5% 1H-NMR (300 MHz, CDCl3) δ 8.66 (m, 1H), 8.07 (m, 1H), 7.02 (m, 2H), 6.29 (m, 2H), 6.34 (br s, 1H), 4.20-2.80 (m, 34H), 1.44 (s, 27H); 13C-NMR (75 MHz, CDCl3) δ 174.51, 174.14, 173.70, 173.45, 172.43, 169.80, 167.18, 156.59, 156.45, 130.43, 130.02, 125.93, 116.08, 115.89, 81.89, 81.85, 81.75, 56.42, 55.62, 52.76, 52.32, 51.61, 50.52, 49.67, 49.31, 49.25, 49.12, 47.69, 47.52, 43.54, 43.21, 40.37, 39.38, 38.07, 28.14.

1. customAfter solvent removal
2. customin vacuo, purification
3. customto give 3