Water → Diisopropyl Ether

Participants

Reaction Conditions

Reaction Steps

3-Acetoxymethyl-2-carboxy-7-[(2-mesyl-imidazol-1-yl)-acetamido]-8-oxo-5-thia-1-aza-bicyclo[4,2,0]oct-2-ene (13.7 g.) and sodium bicarbonate (2.52 g.) are dissolved in water (140 cc.). A solution of 2-methyl-5-thioxo-1,3,4-thiadiazoline (4.75 g.) and sodium bicarbonate (3.0 g.) in water (160 cc.) is added. The mixture is heated at 60° C. for 12 hours. The mixture is allowed to cool, washed with ethyl acetate (100 cc.) and acidified to pH 2 by adding 6 N hydrochloric acid. A product precipitates and is filtered off and taken up, with stirring, in methanol (20 cc.). The solid is again filtered off and washed with methanol (40 cc.) and then with isopropyl ether (30 cc.) to give 2-carboxy-7-[(2-mesyl-imidazol-1-yl)-acetamido]-3-[(5-methyl-1,3,4-thiadiazol-2-yl)-thiomethyl]-8-oxo-5-thia-1-aza-bicyclo-[4,2,0]oct-2-ene (6.2 g.), m.p. approximately 196° C., [α]D20 = -56° ± 2° (c= 1, dimethylformamide).

Provenance & Evidence