Hydrochloric Acid → benzhydryl (6R,7R)-7-[[(2Z)-2-cyclopentyloxyimino-2-[2-[(2-methylpropan-2-yl)oxycarbonylamino]-1,3-thiazol-4-yl]acetyl]amino]-3-methylsulfonyloxy-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Steps

To a suspension of 7β-amino-3-methanesulfonyloxy-3-cephem-4-carboxylic acid diphenylmethyl ester hydrochloride (1.49 g: 3 mMol.) and (Z)-2-(2-t-butoxycarbonylaminothiazol-4-yl)-2-cyclopentyloxyimino-acetic acid (1.23 g: 3.5 mMol.) in dichloromethane (30 ml) at -30° C. are added N-methylmorpholine (1.1 ml: 10 mMol.) and, after 1 minute, phenyl dichlorophosphate (0.49 ml: 3.3 mMol.), and the mixture is stirred at the same temperature for 2 hours. The reaction mixture is mixed with 1N-hydrochloric acid (6 ml) and water (50 ml) and extracted with ethyl acetate. The extract is washed with water, 5% aqueous sodium hydrogen carbonate, and water, dried over sodium sulfate, and purified by silica gel chromatography (toluene: ethyl acetate=5:1, containing 0.5% acetic acid) to give 7β-[(Z)-2-(2-t-butoxycarbonylaminothiazol-4-yl)-2-cyclopentyloxyiminoacetamido]-3-methanesulfonyloxy-3-cephem-4-carboxylic acid diphenylmethyl ester (1.86 g) as white foam. Yield: 78%.

Provenance & Evidence