反应 #62778

反应方程式

diisopropyl ether

anisole

trifluoroacetic acid

benzhydryl 7-[2-(2-tritylaminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(1-methyl-1-pyrrolidiniomethyl)-3-cephem-4-carboxylate trifluoroacetate

→

7-[2-(2-aminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(1-methyl-1-pyrrolidiniomethyl)-3-cephem-4-carboxylate

收率 72.4%

溶剂

methylene chloride

反应条件

后处理

1. 1
   其他the resultant precipitates
2. 2
   过滤were collected by filtration
3. 3
   洗涤washed with diisopropyl ether
4. 4
   workup.DISSOLUTIONdissolved in water (400 ml)
5. 5
   洗涤the elution
6. 6
   workup.ADDITIONThe fractions containing the object compound
7. 7
   其他were collected
8. 8
   浓缩concentrated in vacuo

实验过程

A solution of benzhydryl 7-[2-(2-tritylaminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(1-methyl-1-pyrrolidiniomethyl)-3-cephem-4-carboxylate trifluoroacetate (syn isomer) (1.25 g) in methylene chloride (4 ml) was stirred at 0°-5° C., and anisole (2.6 ml) and trifluoroacetic acid (5.2 ml) were added thereto. The mixture was stirred for one hour at 0°-5° C. To the reaction mixture was added diisopropyl ether, and the resultant precipitates were collected by filtration, washed with diisopropyl ether and dissolved in water (400 ml). The solution was subjected to column chromatography on macroporus non-ionic adsorption resin "Diaion HP-20" and the elution was carried out with 30% aqueous solution of methanol. The fractions containing the object compound were collected, concentrated in vacuo and lyophilized to give 7-[2-(2-aminothiazol-4-yl)-2-difluoromethoxyiminoacetamido]-3-(1-methyl-1-pyrrolidiniomethyl)-3-cephem-4-carboxylate (syn isomer) (450 mg).

来源