Methanesulfonic Acid → HCID 13175153, compound

Participants

Reaction Steps

A solution of 3-(2-acetamido-thiazol-5-yl)-2-benzhydryloxycarbonyl-7-t-butoxycarbonylamino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene (6.06 g) in acetonitrile (100 cc) is stirred with methanesulphonic acid (6 cc) for 30 minutes at 20° C., then diluted with ethyl acetate (200 cc) and stirred with a saturated sodium bicarbonate solution (300 cc). The aqueous layer is extracted with ethyl acetate (100 cc) and the combined organic solutions are washed with a half-saturated sodium chloride solution (2×250 cc), then dried over magnesium sulphate, and concentrated to dryness under reduced pressure (30 mm Hg; 4 kPa) at 40° C. 3-(2-Acetamido-thiazol-5-yl)-7-amino-2-benzhydryloxycarbonyl-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene (4.9 g) is obtained in the form of a yellow froth. This product is redissolved in dry tetrahydrofuran (75 cc). The solution, cooled to about 0° C, is treated successively with phenylacetyl chloride (1.54 g) and triethylamine (1.4 cc) and then stirred for 1 hour at between 0° and 4° C. The reaction mixture is diluted with ethyl acetate (100 cc) and a half-saturated sodium bicarbonate solution (200 cc). The organic layer is decanted, washed with water (100 cc) and then with a half-saturated sodium chloride solution (100 cc), dried over magnesium sulphate and concentrated to dryness under reduced pressure (30 mm Hg; 4 kPa) at 40° C. The residue is taken up in methylene chloride (25 cc). The precipitate is filtered off and then taken up in boiling acetonitrile (80 cc). After the mixture has cooled, the precipitate is filtered off, washed with acetonitrile (10 cc) and dried under reduced pressure (2 mm Hg; 0.27 kPa) at 25° C. 3-(2-Acetamido-thiazol-5-yl)-2-benzhydryloxycarbonyl-8-oxo-7-phenylacetamido-5-thia-1-azabicyclo[4.2.0]oct-2-ene (2.65 g) is thus obtained in the form of a white solid.

Provenance & Evidence