Acetone → HCID 23135943, compound

Temperature

40 °C

10.0 g (0.06 mol) of 2-methylcysteinamide hydrochloride as a racemic body was dissolved in 300 ml of water, and the obtained solution was then placed in a 500-ml flask. Thereafter, an aqueous manganese chloride solution was added thereto, such that the concentration of divalent Mn ions became 10 ppm. Thereafter, the intact cells corresponding to 1.0 g of dried cells were further added thereto. The mixture was stirred at 40° C. for 24 hours under nitrogen flow, so as to carry out hydrolysis. After completion of the reaction, the cells were removed from the reaction solution by centrifugation to obtain a supernatant. This supernatant was concentrated using a rotary evaporator, and the concentrate was then dissolved in 150 ml of methanol. Subsequently, 200 ml of acetone and 3.6 g (0.03 mol) of sodium carbonate were added thereto, and the mixture was stirred at room temperature for 16 hours, so as to carry out the reaction. Thereafter, the reaction solution was concentrated, and then supplemented with 50 ml of isobutyl alcohol and subjected to reflux conditions for 4 hours so as to extract soluble matters. After cooling, crystals that remained as insoluble matters were separated by filtration. The obtained crystals were recrystallized from ethanol to obtain colorless transparent crystals of 2,2,4-trimethylthiazolidine-4-carboxylic acid. The obtained 2,2,4-trimethylthiazolidine-4-carboxylic acid was dissolved in 100 ml of pure water, and the obtained solution was refluxed under nitrogen flow for 3 hours. Thereafter, the reaction solution was concentrated using a rotary evaporator, followed by drying under reduced pressure, to obtain 3.1 g (0.02 mol) of 2-methyl-L-cysteine. The yield of isolation was found to be 78 mol % relative to 2-methyl-L-cysteinamide contained in the racemic body that had been used for the reaction, and was found to be 39 mol % relative to 2-methylcysteinamide as a racemic body. Moreover, this solid was analyzed by liquid chromatography using an optical isomer separation column. As a result, the optical purity thereof was found to be 95% e.e. or more.

1. customthe obtained solution was then placed in a 500-ml flask
2. additionThereafter, the intact cells corresponding to 1.0 g of dried cells were further added
3. customhydrolysis
4. customAfter completion of the reaction
5. customthe cells were removed from the reaction solution by centrifugation
6. customto obtain a supernatant
7. concentrationThis supernatant was concentrated
8. customa rotary evaporator
9. dissolutionthe concentrate was then dissolved in 150 ml of methanol
10. stirringthe mixture was stirred at room temperature for 16 hours
11. customthe reaction
12. concentrationThereafter, the reaction solution was concentrated
13. temperatureto reflux conditions for 4 hours so as
14. extractionto extract soluble matters
15. temperatureAfter cooling
16. customwere separated by filtration
17. customThe obtained crystals were recrystallized from ethanol

ORD record

ord-1998295d847445cbb05d269674843506

Source dataset

uspto-grants-2008_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07470525B2