Sodium Iodide → 2,2-dimethylpropanoyloxymethyl (6R,7R)-7-[[(2Z)-2-(2-amino-1,3-thiazol-4-yl)-2-methoxyiminoacetyl]amino]-8-oxo-3-[(2R)-oxolan-2-yl]-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylate

Participants

Reaction Steps

Pivaloyloxymethyl bromide (247mg, 1.27mmol) and sodium iodide (247mg, 1.65mmol) in acetone (5ml) were stirred for 30 min., filtered, and the filtrate concentrated in vacuo. The resulting iodide in toluene (3ml) was added to a solution of sodium (6R,7R)-7-[2-(2-aminothiazol-4-yl)-2-(Z)-methoxyiminoacetamido]-3-[(R)-tetrahydrofuran-2-yl]ceph-3-em-4-carboxylate (320mg, 0.67mmol) in N-methylpyrrolidinone (5ml). After stirring for 30 min. at room temperature, the reaction mixture was diluted with ethyl acetate, washed successively with water (x3) and brine, dried over MgSO4 and concentrated in vacuo. The residue was chromatographed on silica gel eluting with 80% ethyl acetate in hexane to give the title compound as a yellow foam (297mg, 78%); vmax (CH2Cl2) 3387, 1786, 1752, 1735, 1686, 1605cm-1 ; δH (CDCl3, 250MHz) 1.22 (9H, s), 1.69 (1H, m), 1.98 (2H, m), 2.18 (1H, m), 3.43 and 3.62 (2H, ABq, J 18.0Hz), 3.80-3.96 (2H, m), 4.10 (3H, s), 5.08 (1H, d, J 4.7Hz), 5.19 (1H, m), 5.83-5.92 (3H, m), 6.32 (2H, br. s, exch), 7.02 (1H, s), 7.63 (1H, br. d, exch., J 8.6Hz). [Mass spectrum: +ve ion (thioglycerol) MH+ (568)].

Provenance & Evidence