Methanol → HCID 53642024, compound

Participants

Reaction Conditions

Reaction Steps

Phosphorus pentachloride (48 mg, 0.23 mmol) in dichloromethane (1.2 ml) was added to 4-methoxybenzyl (6R,7R)-3-[(S)-5,5-dimethyltetrahydrofuran-2-yl]-7-phenylacetamidoceph-3-em-4-carboxylate (93 mg, 0.15 mmol) and N-methylmorpholine (34 μl, 0.31 mmol) in dichloromethane (3 ml) at -25° C. The reaction was stirred at -10+5° C. for 45 min., then methanol (0.5 ml) was added, and stirring continued for 45 min. at room temperature. Water (1 ml) was then added, and the mixture vigorously stirred for a further 1 h. After evaporation of the dichloromethane in vacuo, the pH of the aqueous residue was adjusted to 7 by the addition of ammonium hydroxide in the presence of ethyl acetate. The mixture was extracted with ethyl acetate (×2), dried and concentrated in vacuo. The residue was purified by chromatography on silica gel eluting with 70% ethyl acetate in hexane yielding the title compound (25 mg, 39%); (Found: M+ 418.1566. C21H26N2O5S requires M+ 418.1562); νmax (CH2Cl2) 2970, 1777, 1721, 1613 and 1516 cm-1 ; δH (CDCl3, 250 MHz) 1.21 (3H, s), 1.27 (3H, s), 1.68-1.81 (3H, m), 2.25 (1H, m), 3.48 and 3.62 (2H, ABq, J 18.7 Hz), 3.56 (2H, br s, exch.), 3.79 (3H, s), 4.73-5.25 (5H, m), 6.87 (2H, d, J 8.6 Hz) and 7.30 (2H, d, J 8.6 Hz).

Provenance & Evidence