反应详情

温度

5 °C

The sodium salt of 2-carboxy-3-[(1-methyl-1,2,3,4-tetrazol-5-yl)-thiomethyl]-8-oxo-7-[(1,3-dithiol-2-on-4-yl)-acetamido]-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene (5.08 g.) is dissolved in dimethylformamide (100 cc.) at 5° C. A solution of iodomethyl acetate (2 g.) in dimethylformamide (10 cc.) is added to this solution and the reaction mixture is stirred for 10 minutes at 5° C. It is then poured into water (500 cc.) and extracted twice with ethyl acetate (200 cc.). The combined organic phases are washed with water (100 cc.), saturated sodium bicarbonate solution (100 cc.), a 5% sodium bisulphite solution (100 cc.) and a saturated sodium chloride solution (100 cc.). The organic phase is dried over magnesium sulphate, filtered in the presence of decolourising charcoal and concentrated to dryness under reduced pressure (15 mm Hg). This gives a white product (5 g.) which is recrystallised from acetonitrile (50 cc.). 2-Acetoxymethoxycarbonyl-3-[(1-methyl-1,2,3,4-tetrazol-5-yl)thiomethyl]-8-oxo-7-[(1,3-dithiol-2-on-4-yl)-acetamido]-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene (3 g.) is thus obtained as white crystals m.p. 154° C.

1. extractionextracted twice with ethyl acetate (200 cc.)
2. washThe combined organic phases are washed with water (100 cc.), saturated sodium bicarbonate solution (100 cc.)
3. dry with materialThe organic phase is dried over magnesium sulphate
4. filtrationfiltered in the presence of decolourising charcoal
5. concentrationconcentrated to dryness under reduced pressure (15 mm Hg)
6. customThis gives a white product (5 g.) which
7. customis recrystallised from acetonitrile (50 cc.)