反应 #5622

反应方程式

7β-[2-(2-formamidothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetamido]-3-(1-methyl-4-tert-butoxycarbonyl-1-piperazinio)methyl-3-cephem-4-carboxylate hydrochloride

hydrochloric acid

ethyl acetate

→

7β-[2-(2-aminothiazol- 4-yl)-2-carboxymethoxyiminoacetamido]-3-(1-methyl-1-piperazinio)methyl-3-cephem-4-carboxylate

收率 26.7%

溶剂

methanol

反应条件

后处理

1. 1
   过滤the powder was collected by filtration
2. 2
   洗涤washed with ethyl acetate
3. 3
   其他dried in vacuo
4. 4
   workup.ADDITIONThe powder (3.68 g) was suspended in a mixture of dichloromethane (12 ml) and anisole (4 ml), and trifluoroacetic acid (8 ml)
5. 5
   workup.ADDITIONwas added
6. 6
   workup.STIRRINGAfter being stirred at room temperature for 3.5 hours
7. 7
   过滤the powder was collected by filtration
8. 8
   洗涤washed with diisopropyl ether
9. 9
   workup.ADDITIONThe powder was suspended in a mixture of water (100 ml) and ethyl acetate (30 ml)
10. 10
    其他After removal of the insoluble materials
11. 11
    其他the aqueous layer was separated
12. 12
    其他chromatographed on Diaion HP-20 (250 ml)
13. 13
    洗涤The elution

实验过程

To a suspension of 7β-[2-(2-formamidothiazol-4-yl)-2-tert-butoxycarbonylmethoxyiminoacetamido]-3-(1-methyl-4-tert-butoxycarbonyl-1-piperazinio)methyl-3-cephem-4-carboxylate hydrochloride (syn isomer) (4.02 g) in methanol (12 ml) was added conc. hydrochloric acid (4.4 ml) at 10° C. The resulting solution was warmed to room temperature and stirred for 4.5 hours. The mixture was pulverized with ethyl acetate (800 ml) and the powder was collected by filtration, washed with ethyl acetate and dried in vacuo. The powder (3.68 g) was suspended in a mixture of dichloromethane (12 ml) and anisole (4 ml), and trifluoroacetic acid (8 ml) was added thereto. After being stirred at room temperature for 3.5 hours, the mixture was pulverized with diisopropyl ether (800 ml) and the powder was collected by filtration and washed with diisopropyl ether. The powder was suspended in a mixture of water (100 ml) and ethyl acetate (30 ml) and adjusted with a saturated aqueous solution of sodium bicarbonate. After removal of the insoluble materials, the aqueous layer was separated, adjusted to pH 4 with 1N hydrochloric acid and chromatographed on Diaion HP-20 (250 ml). The elution was carried out with 10% aqueous isopropyl alcohol. The eluate was lyophilized to give 7β-[2-(2-aminothiazol- 4-yl)-2-carboxymethoxyiminoacetamido]-3-(1-methyl-1-piperazinio)methyl-3-cephem-4-carboxylate (syn isomer) (763 mg).

来源