Dicyclohexylcarbodiimide → benzhydryl (6R,7R)-3-[(1-methyltetrazol-5-yl)sulfanylmethyl]-8-oxo-7-[[(2Z)-2-(2-oxopyrrolidin-3-yl)oxyimino-2-[2-(tritylamino)-1,3-thiazol-4-yl]acetyl]amino]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Steps

3.25 g of (Z)-2-(2-tritylaminothiazol-4-yl)-2-[(2-pyrrolidon-3-yl)oxyimino]acetic acid are dissolved in 200 ml of tetrahydrofuran, and 3.14 g of benzhydryl 7β-amino-3-[(1-methyl-1H-tetrazol-5-yl)thiomethyl]-3-cephem-4-carboxylate, 1.03 g of 1-hydroxybenzotriazole and 1.57 g of dicyclohexylcarbodiimide are added thereto. The mixture is stirred at room temperature for 2 hours. Insoluble materials are filtered off, and the filtrate is concentrated to dryness under reduced pressure. The residue is dissolved in ethyl acetate, and washed with 1% hydrochloric acid, 5% aqueous sodium bicarbonate solution and an aqueous saturated sodium chloride solution, successively. The ethyl acetate solution is then dried and concentrated to dryness under reduced pressure. The residue thus obtained is purified by silica gel chromatography (solvent, ethyl acetate: benzene=5:2). 3.7 g of benzhydryl 7β-{(Z)-2-(2-tritylaminothiazol-4-yl)-2-[(2-pyrrolidon-3-yl)oxyimino]acetamido}-3-[(1-methyl-1H-tetrazol-5-yl)thiomethyl] -3-cephem-4-carboxylate are obtained.

Provenance & Evidence