N-[N-(tert-Butoxycarbonyl)-O-benzyl-L-seryl]-D-leucine methyl ester → HCID 54521511, compound

Participants

Reaction Steps

N-[N-(tert-Butoxycarbonyl)-O-benzyl-L-seryl]-D-leucine methyl ester (545 mg) was dissolved in 4N HCl-AcOEt (5 ml), and the solution was stirred at ambient temperature for 1.5 hours. The solvent was evaporated in vacuo. The resulting oil was dissolved in dry MeOH (5 ml). Benzaldehyde (205 mg) and sodium cyanoborohydride (NaBH3CN, 97 mg) were added to this solution, and the reaction mixture was stirred at ambient temperature for 3 hours. Benzaldehyde (60 mg) and NaBH3CN (30 mg) were added to the reaction mixture and the mixture was stirred at ambient temperature for 1.5 hours. After evaporation of the solvent in vacuo, the residue was partitioned by dissolving same in AcOEt and saturated aqueous NaHCO3 solution. The organic layer was washed with saturated sodium chloride (NaCl) solution, dried over MgSO4, and concentrated in vacuo. The residue was purified by SiO2 column chromatography (eluent: CHCl3) to give 376 mg of N-(N,O-dibenzyl-L-seryl)-D-leucine methyl ester as an oil.

Provenance & Evidence