Citric Acid → HCID 178450878, compound

Participants

Reaction Steps

A solution of 2-(2-tritylaminothiazol-4-yl)-(Z)-2-(1-tert-butoxycarbonylcyclopentyloxyimino)acetic acid (2.80 g, 4.7 mmol), 1-hydroxybenzotriazole (0.73 g, 5.4 mmol) and N,N'-dicyclohexylcarbodiimide (1.07 g, 5.17 mmol) in dimethylacetamide (26 ml) was stirred at room temperature for 2.5 hours. To the solution was added a solution of 7β-amino-3-[(1-amino-1H-tetrazol-5-yl)thiomethyl]-3-cephem-4-carboxylic acid (1.70 g, 5.17 mmol) and triethylamine (1.05 g, 10.3 mmol) in dimethylacetamide (13 ml) and water (1.7 ml), and the mixture was stirred at room temperature for 17 hours. The mixture was acidified with citric acid to pH 3.5 and extracted with ethyl acetate. The extract was washed with water, dried over magnesium sulfate, and evaporated. The residue was treated with isopropyl ether to give pale brown powder of 7β-[2-(2-tritylaminothiazol-4-yl)-(Z)-2-(1-tert-butoxycarbonylcyclopentyloxyimino)acetamido]-3-[(1-amino-1H-tetrazol-5-yl)thiomethyl]-3-cephem-4-carboxylic acid (3.3 g).

Provenance & Evidence