Reacción #3361

Ecuación de reacción

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

Disolventes

dichloromethane

Condiciones de reacción

Tratamiento posterior

1. 1
   Concentraciónconcentrated to dryness in vacuo
2. 2
   OtroThe residue was triturated with dichloromethane
3. 3
   OtroThe dichloromethane was removed by evaporation in vacuo
4. 4
   Otroto remove excess bromine
5. 5
   OtroThe residue was partitioned between dichloromethane/5% aqueous sodium bicarbonate (200 mL each)
6. 6
   OtroThe aqueous layer was separated
7. 7
   Lavadowashed with fresh dichloromethane
8. 8
   ExtracciónThe acidic aqueous solution was extracted with dichloromethane (2×75 mL)
9. 9
   Lavadowashed with water
10. 10
    Secadodried (MgSO4)
11. 11
    Filtraciónfiltered
12. 12
    Concentraciónconcentrated to dryness in vacuo

Procedimiento

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.

Fuente