L-(+)-Cysteine → 2-Amino-3-(2-hydroxyethylsulfanyl)propanoic acid

Temperature

10 °C

36.3 g of L-cysteine was dissolved in 300 ml of water. 24 ml 1 mol/L of NaOH solution was added into above solution and cooled by ice-water bath in order to adjust pH value to 7. And then at 0° C. 30 mL of epoxy ethane was added dropwise to the above solution and then mixture was cooled to 10° C. After the mixture was stirred for 1.0 hour, it was warmed to room temperature and then stirred for 1.5 hours. The resultant mixture was extracted with ethyl ether three times (60 ml, 45 ml, 45 ml) to remove the residual epoxy ethane. Water layer was removed on a rot-vap to obtain a buff solid. The solid was recrystallized in 95% ethanol to obtain a white lamellar crystal (33.9 g). Yield 69.4%□mp 195-196° C. (Dec.).

1. temperaturecooled by ice-water bath in order
2. customat 0° C
3. temperatureit was warmed to room temperature
4. stirringstirred for 1.5 hours
5. extractionThe resultant mixture was extracted with ethyl ether three times (60 ml, 45 ml, 45 ml)
6. customto remove the residual epoxy ethane
7. customWater layer was removed on a rot-vap
8. customto obtain a buff solid
9. customThe solid was recrystallized in 95% ethanol

ORD record

ord-513bed1bcdcc42619ccaf5b21510bf2d

Source dataset

uspto-grants-2007_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07304057B2