反应 #54595
ord-159163d686044074918c63f16e83fe3d
反应方程式
反应物
试剂
反应条件
后处理
- 1workup.STIRRINGthe mixture stirred for 4 hours
- 2过滤The reaction mixture is filtered
- 3浓缩concentrated by flash evaporation
- 4workup.DISSOLUTIONthe residue is dissolved in 25 ml of water
- 5洗涤washed several times with ether
- 6其他A small amount of solid is removed by filtration
- 7其他the organic phase is separated
- 8其他dried
- 9浓缩concentrated to 5 ml
实验过程
A solution of the monoethyl ester of 2(1-pyrryl) propanedioic acid (1 g., 5.07 mM) and 0.87 g. (5.2 mM) of N, N"-carbonyldiimidazole in 10 ml of dimethylformamide is stirred at room temperature for one hour. In a second flask, 3[(acetyloxy)methyl]-7-amino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid (1.37 g, 5.07 mM) is dissolved in 35 ml of chloroform upon the addition of 2.05 g (20.3 mM) of triethylamine and is stirred under nitrogen for 30 minutes in the presence of Linde 44 molecular sieves. The two solutions are combined and the mixture stirred for 4 hours after the addition of 0.5 g of charcoal. The reaction mixture is filtered, concentrated by flash evaporation and the residue is dissolved in 25 ml of water and washed several times with ether. The aqueous phase is covered with 50 ml of ethyl acetate and is then acidified to pH of 2.5 with 6 N hydrochloric acid. A small amount of solid is removed by filtration and the organic phase is separated, dried and concentrated to 5 ml. The title compound is obtained as a powder (425 mg., 19% yield) upon addition of the ethyl acetate solution to hexane.