Ethanol → HCID 69541968, compound

Participants

Reaction Steps

Acetic anhydride (0.88 mL, 9.28 mmol) was added under argon to a solution of 15 (2.50 g, 7.14 mmol) in dry pyridine (50 mL) and the resulting mixture was stirred at room temperature for 22 h. Then, ethanol was added and the solvents were evaporated under reduced pressure. The residue was purified by silica gel column chromatography [eluent: stepwise gradient of methanol (0-2%) in methylene chloride] to give pure 16 (2.69 g, 96%) as a white foam; mp=68-70° C. (foam); UV (ethanol): λmax=239 nm (ε=15000) 267 nm (ε=8800), λmin=248 nm (ε=5600); 1H NMR (DMSO-d6): δ ppm 11.9 (br s, 1H, NH), 8.1-7.5 (m, 6H, C6H5CO and H-6), 6.10 (d, 1H, H-1′, J1′-2′=4.3 Hz), 5.4 (m, 1H, H-2′), 4.6-4.4 (m, 3H, H-4′, H-5′ and H-5″), 2.6 (m, 1H, H-3′), 2.03 (m, 1H, H-3″), 1.86 (s, 3H, CH3CO); MS (matrix GT): FAB>0 m/z 785 (2M+H)+, 393 (M+H)+, 263 (S)+, 131 (BH2)+, 105 (C6H5CO)+; 43 (CH3CO)+; FAB<0 m/z 391 (M−H)−, 129 (B)−, 121 (C6H5CO2)−, 59 (CH3CO2)−; [α]D20=−81 (c, 0.95 DMSO).

Provenance & Evidence