Reaction Steps
Ecteinascidin 770 (50) (2.2 mg, 0.00285 mmol, 1 equiv) was dissolved in a mixture of acetonitrile and water (3:2 (v/v), 1.0 mL), and to this solution was added solid silver nitrate (15 mg, 0.088 mmol, 30 equiv). The suspension was stirred at 23° C. for 11 h at which time a mixture of saturated aqueous sodium chloride solution and saturated aqueous sodium bicarbonate solution (1:1 (v/v), 2.0 mL) was added. The mixture was stirred vigorously at 23° C. for 15 min before it was partitioned between a mixture of saturated aqueous sodium chloride solution and saturated aqueous sodium bicarbonate solution (1:1 (v/v), 15 mL) and dichloromethane (3×10 mL). The combined organic layers were dried (sodium sulfate) and filtered through a pad of celite. The filtrate was concentrated to give clean 1 (2.0 mg, 95%), identical in all respects to that of an authentic sample. HPLC (Zorbax ODS, C18, 4.6 mm×25 cm, flow rate: 1.0 mL/min) RT 11.28 min (co-injection, 25% CH3 CN in H2O with 0.2% TFA); [a]D23 -34 (c=0.10, CH2 Cl2); 1H NMR (500 MHz, CDCl2) d 6.59 (s, 1H, ArH), 6.47 (s, 1H, ArH), 6.46 (s, 1H, ArH), 6.03 (d, 1H, J=1.1 Hz, OCH2O), 5.98 (d, 1H, J=1.1 Hz, OCH2O), 5.80 (s, 1H), 5.09 (d, 1H, J=10.9 Hz), 4.77 (s (br), 1H), 4.43 (d, 1H, J=2.8 Hz), 4.36 (m, 1H), 4.05 (dd, 1H, J=2.4, 11.2 Hz), 3.79 (s, 3H, OCH3), 3.61 (s, 3H, OCH3), 3.54 (d, 1H, J=4.5 Hz), 3.20 (m, 1H), 3.10 (m, 1H), 2.84 (m, 2H), 2.78 (m, 1H), 2.57 (m, 1H), 2.40 (dt, 1H, J=15.9, 3.3 Hz), 2.32 (s, 3H, NCH3), 2.26 (s, 3H, ArCH3), 2.17 (s, 3H, ArCH3), 2.02 (s, 3H, AcO); 13 C NMR (100 MHz, CD2Cl2) d 162.2, 141.0, 121.1, 114.4, 109.7, 102.7, 82.1, 65.3, 62.5, 61.2, 60.6, 59.7, 56.4, 55.7, 55.5, 42.9, 40.6, 40.3, 30.1, 24.7, 20.5, 16.1, 9.9; FTR (neat film) 3400 (m, br), 2933 (s), 1760 (m), 1741 (s), 1456 (s), 1448 (s), 1430 (s), 1235 (s), 1195 (s), 1088 (s) cm-1 ; Exact Mass (ES+) m/z: Calcd for C39H44 N3O11S (MH+) 762.2697, found 762.2683.
