Potassium Carbonate → acetyloxymethyl (6R)-7-[[(2Z)-2-(2-amino-1,3-thiazol-4-yl)-2-methoxyiminoacetyl]amino]-3-[(Z)-but-1-enyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a mixture of 7-[(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3-[(Z)-1-butenyl]-3-cephem-4-carboxylic acid (300 mg, 0.69 m mole) and K2CO3 (95 mg, 0.69 m mole) in dry DMF (3 ml) was added dropwise at 0° C. a solution of bromomethyl acetate (105 mg, 0.69 m mole) in dry DMF (0.25 ml) and the mixture was stirred at 0° C. for 15 minutes. To the mixture was added again a solution of bromomethyl acetate (105 mg, 0.69 m mole) in dry DMF (0.25 ml). The reaction mixture was stirred for another 30 minutes and diluted with ethyl acetate (20 ml). The dilute was washed with water and a saturated NaCl solution, dried over anhydrous Na2SO4 and evaporated to dryness. The residue was dissolved in methanol and passed through a column of the packing (40 ml) of a PrepPAK cartridge (Waters), which was washed with water and then eluted with 50% methanol. The eluate was monitored by HPLC. The desired fractions were collected and evaporated to give 96 mg (27%) of the title compound. Estimated purity 90% (by HPLC). M.p. 149°-152° C.

Herkunft & Nachweise