反応 #451733

反応方程式

4-nitrobenzyl 7-[2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate

acetic acid

water

hydrogen

→

7-[2-(2 -formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylic acid

収率 79.7%

溶媒

tetrahydrofuran

methanol

反応条件

後処理

1. 1
   その他After removing the catalyst
2. 2
   ろ過by filtration
3. 3
   濃縮the filtrate was concentrated to a volume of about 15 ml
4. 4
   workup.ADDITIONWater (30 ml.) and ethyl acetate (50 ml.) were added to the concentrated solution
5. 5
   その他The insoluble substance was removed by filtration
6. 6
   その他the aqueous layer was separated
7. 7
   洗浄washed with ethyl acetate (50 ml.)
8. 8
   workup.ADDITIONThe solution was treated, with activated charcoal
9. 9
   ろ過The precipitates were collected by filtration
10. 10
    洗浄washed with water

実験手順

A suspension of 4-nitrobenzyl 7-[2-(2-formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylate (anti isomer, 4.2 g.), 10% palladium carbon (1.7 g.), acetic acid (0.63 ml.), water (6.3 ml.), methanol (42 ml.), and tetrahydrofuran (84 ml.) was subjected to catalytic reduction in a hydrogen atmosphere at room temperature for 2 hours. After removing the catalyst by filtration, the filtrate was concentrated to a volume of about 15 ml. under reduced pressure. Water (30 ml.) and ethyl acetate (50 ml.) were added to the concentrated solution, and the solution was adjusted to pH 8.0 with sodium bicarbonate under stirring. The insoluble substance was removed by filtration, and the aqueous layer was separated and washed with ethyl acetate (50 ml.). The solution was treated, with activated charcoal, and adjusted to pH 2.2 with 10% hydrochloric acid under ice cooling. The precipitates were collected by filtration and washed with water to give 7-[2-(2 -formamidothiazol-4-yl)-2-methoxyiminoacetamido]-3-cephem-4-carboxylic acid (anti isomer, 2.52 g.).

出典