Methanesulfonyl chloride → benzhydryl (6R,7R)-7-[[(2Z)-2-methoxyimino-2-[2-(tritylamino)-1,3-thiazol-4-yl]acetyl]amino]-8-oxo-3-[(5-oxo-2H-furan-4-yl)methylsulfanyl]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Conditions

Reaction Steps

A stirred solution of 2-(2-Tritylaminothiazol-4-yl)-2-(Z)-methoxyiminoacetic acid hydrochloride (287 mg) and diisopropylethylamine (0.208 ml) in dry dimethylformamide (5 ml) was cooled to -50° C. under an inert atmosphere. Treatment with methanesulfonyl chloride (0.047 ml) was followed by stirring at -50° C. for 45 min. Pyridine (0.048 ml) and a solution of diphenylmethyl-7β-amino-3-(2,5-dihydro-2-oxofuran-3-ylmethylthio)ceph-3-em-4-carboxylate (298 mg) in dimethylformamide (3 ml) were then added and the reaction allowed to warm to 0° C. The reaction was stirred at 0° C. for 90 min. before pouring into ethyl acetate/water. The ethyl acetate was separated and washed three times with water, saturated sodium bicarbonate solution, and brine before drying over magnesium sulphate. Evaporation of solvent and chromatography of the residue on silica gel(Keiselgel 7:3 ethyl acetate:hexane) gave the title compound (364 mg). υmax (CH2Cl2) 3400, 1780, and 1760cm-1 ; δH (CDCl3) 3.50 (1H, d, J 17.4Hz), 3.53 (2H, s), 3.67 (1H, d, J 17.4Hz), 4.08 (3H, s), 4.72 (2H, s), 5.08 (1H, d, J 4.7Hz), 5.88 (1H, dd, J 8.6Hz, 4.7Hz), 6.76 (1H, s), 6.83 (1H, d, J 8.8Hz), 6.90 (1H, s), 6.95 (1H, s), 7.16-7.46 (26H, m). [mass spectrum: +ve ion (3NOBA, Na+) MNa+ 942].

Provenance & Evidence