반응 #3361

반응 방정식

2-[2-(1-carboxy-2-methylbutylcarbamoyl) phenyldisulfanylbenzoylamino]-3-methylpentanoic acid

bromine

→

title compound

3-Methyl-2-(3-oxo-3h-benzo[d]isothiazol-2-yl)pentanoic acid

용매

dichloromethane

반응 조건

후처리

1. 1
   농축concentrated to dryness in vacuo
2. 2
   기타The residue was triturated with dichloromethane
3. 3
   기타The dichloromethane was removed by evaporation in vacuo
4. 4
   기타to remove excess bromine
5. 5
   기타The residue was partitioned between dichloromethane/5% aqueous sodium bicarbonate (200 mL each)
6. 6
   기타The aqueous layer was separated
7. 7
   세척washed with fresh dichloromethane
8. 8
   추출The acidic aqueous solution was extracted with dichloromethane (2×75 mL)
9. 9
   세척washed with water
10. 10
    건조dried (MgSO4)
11. 11
    여과filtered
12. 12
    농축concentrated to dryness in vacuo

실험 절차

To a stirred suspension of 5.3 g (10.0 mmol) of [S-(R*,R*)]-2-[2-[2-(1-carboxy-2-methylbutylcarbamoyl) phenyldisulfanylbenzoylamino]-3-methylpentanoic acid (from Preparation 19) in 200 mL of dichloromethane was added dropwise 2.4 g (15.0 mmol) of liquid bromine. The reaction mixture was stirred at room temperature for 2 hours and concentrated to dryness in vacuo. The residue was triturated with dichloromethane. The dichloromethane was removed by evaporation in vacuo to remove excess bromine. The residue was partitioned between dichloromethane/5% aqueous sodium bicarbonate (200 mL each). The aqueous layer was separated, washed with fresh dichloromethane, and acidified to pH 1.5 with 6.0M hydrochloric acid. The acidic aqueous solution was extracted with dichloromethane (2×75 mL). The organic layers were combined, washed with water, dried (MgSO4), filtered and concentrated to dryness in vacuo to give 4.8 g of the title compound, mp 50°-52° C.

출처