Ethyl 2-amino-3-sulfanylpropanoate → (+/-)-ethyl alpha-[[[(4-chlorophenyl)[2-chloro-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)phenyl]methyl]thio]methyl]glycine

Participants

Reaction Steps

Sodium (0.075 mol) was added portionwise to ethanol (50 ml) under N2 atmosphere and this mixture was stirred until complete dissolution. Ethyl 2-amino-3-mercaptopropanoate (0.075 mol) was added and the mixture was stirred for 2 hours at RT. The solvent was evaporated, THF (50 ml) was added to the residue, and a solution of 2-[3-chloro-4-[chloro(4-chlorophenyl)methyl]phenyl]-1,2,4-triazine-3,5(2H,4H)-dione (0.015 mol) in THF (50 ml) was added. 1,8-diazabicyclo[5.4.0]undec-7-ene (0.03 mol) was added and the resulting reaction mixture was stirred overnight at RT. The solvent was evaporated. The residue was stirred in water and extracted with CH2Cl2. The organic layer was separated, washed with water, dried, filtered and the solvent was evaporated. This fraction was purified by HPLC over silica gel (eluent: CH2Cl2/CH2OH 97/3). The pure fractions were collected and the solvent was evaporated. The residue was stirred in DIPE, filtered off, washed and dried, yielding (±)-ethyl α-[[[(4-chlorophenyl)[2-chloro-4-(4,5-dihydro-3,5-dioxo-1,2,4-triazin-2(3H)-yl)phenyl]methyl]thio]methyl]glycine (compound 95).

Provenance & Evidence