Sodium Chloride → (6R,7R)-7-[[(2Z)-2-(2-amino-1,3-thiazol-4-yl)-2-trityloxyiminoacetyl]amino]-8-oxo-3-(pyrazin-2-ylmethylsulfanyl)-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-(2-aminothiazol-4-yl)-2-(Z)-(trityloxyimino)acetic acid (3.70 g, 8.61 m mol) in N,N-dimethylacetamide (37 ml) was added potassium carbonate (1.19 g, 8.61 m mol) and methansulfonyl chloride (1.33 ml, 17.2 m mol) at 5° C. The mixture was stirred at 5° C. for 30 minutes. To a solution of 7β-amino-3-[(pyrazin-2-yl)methylthio]-3-cephem-4-carboxylic acid hydrochloride (3.42 g, 8.61 m mol) in DMF (34.2 ml) was added bis(trimethylsilyl)acetamide (14.9 ml, 60.3 m mol), and stirred at 5° C. for 20 minutes. To the solution was added the above-mentioned solution of the activated acid. The mixture was stirred at 5° C. for 1 hour. The reaction mixture was poured into 20% NaCl aq. (350 ml). The precipitates were collected by filtration, washed with water and dried in vacuo to give 7β-[2-(2-aminothiazol-4-yl)-2-(Z)-(trityloxyimino)acetamido]-3-[(pyrazin-2-yl)methylthio]-3-cephem-4-carboxylic acid (6.98 g, 9.49 m mol).

Provenance & Evidence