40 mg |
|
Step 1: Commercially available <strong>[1404-90-6]vancomycin</strong> (100 mg) and DIPEA (30 muL) were dissolved in 3 mL of DMF to give an opaque solution, which was heated to 50 C to become clear. Decanal (30 muL) was added, and the mixture was heated under stirring for 4h. Then, NaCNBH3 (8 mg), 1 mL of methanol and 30 muL of TFA were added at room temperature, and the reaction was stirred overnight and monitored by HPLC. The reaction mixture was added with diethyl ether (50 mL) to generate precipitates, which was filtered to give a crude. The crude was purified by reverse-phase C18 HPLC and lyophilized to give Van-g (40 mg) as a white solid. HPLC: C18 column (5 mum, 4.6 x 250 mm), UV detection at 214 nm, elution conditions: a gradient of 2-90% acetonitrile containing 0.1% v/v TFA over 30 min. HRMS (ESI+) calculated for C76H95Cl2N9O24 [M+2H]2+ 1587.5867, found 794.8006. 1H NMR (600 MHz, DMSO-d6) delta 8.70 (s, 1H), 7.81 (d, J = 1.9 Hz, 1H), 7.52 (d, J = 8.6 Hz, 1H), 7.44 (dd, J = 8.3, 1.8 Hz, 1H), 7.29 (d, J = 8.4 Hz, 1H), 7.17 (d, J = 8.4 Hz, 1H), 7.15 - 7.11 (m, 1H), 6.76 (dd, J = 8.4, 2.0 Hz, 1H), 6.70 (d, J = 8.4 Hz, 2H), 6.38 (d, J = 2.3 Hz, 1H), 6.23 (d, J = 2.3 Hz, 1H), 5.73 (d, J = 7.8 Hz, 1H), 5.59 (s, 1H), 5.27 (dd, J = 22.9, 6.0 Hz, 2H), 5.14 (dd, J = 14.8, 2.8 Hz, 2H), 5.09 (s, 1H), 4.89 (s, 1H), 4.60 (d, J = 6.7 Hz, 1H), 4.42 (dd, J = 11.8, 5.6 Hz, 2H), 4.17 (s, 2H), 3.94 (s, 1H), 3.65 (d, J = 10.8 Hz, 1H), 3.54 (t, J = 8.5 Hz, 1H), 3.31 - 3.22 (m, 3H), 2.74 (s, 1H), 2.67 (d, J = 7.2 Hz, 1H), 2.60 (s, 4H), 2.12 (d, J = 12.6 Hz, 1H), 1.96 (d, J = 11.6 Hz, 1H), 1.77 (d, J = 13.1 Hz, 1H), 1.63 (ddd, J = 26.5, 12.5, 6.7 Hz, 2H), 1.51 (s, 3H), 1.32 (s, 3H), 1.23 (d, J = 18.1 Hz, 16H), 1.06 (d, J = 6.3 Hz, 3H), 0.89 (d, J = 6.2 Hz, 3H), 0.83 (td, J = 7.1, 6.7, 3.6 Hz, 6H). |