Trityl chloride → H-D-Cys(Trt)-OMe*HCl

D-Cysteine methyl ester hydrochloride (2.0 g) was suspended in N,N-dimethylformamide (12 mL), 4N hydrochloric acid/ethyl acetate solution (0.5 mL) was added, and the mixture was stirred at room temperature for 20 min. Trityl chloride (3.2 g) was added, and the mixture was stirred at 50° C. for 18 hr, diluted with diethyl ether, and poured into ice water. The mixture was neutralized with saturated aqueous sodium hydrogencarbonate solution, and extracted with ethyl acetate. The ethyl acetate layer was washed with water and saturated brine, dried (MgSO4), and concentrated. The obtained residue was diluted with ethyl acetate, and 4N hydrochloric acid/ethyl acetate solution (5 mL) was added. The precipitated solid was collected by filtration to give the title compound (3.0 g, yield 64%) as a colorless amorphous solid.

1. stirringthe mixture was stirred at 50° C. for 18 hr
2. extractionextracted with ethyl acetate
3. washThe ethyl acetate layer was washed with water and saturated brine
4. dry with materialdried (MgSO4)
5. concentrationconcentrated
6. additionThe obtained residue was diluted with ethyl acetate, and 4N hydrochloric acid/ethyl acetate solution (5 mL)
7. additionwas added
8. filtrationThe precipitated solid was collected by filtration

ORD record

ord-27ac82ccd3c749bbbc9e985053de1530

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07777047B2