161529-13-1

35661-39-3

161529-13-1

GENERAL METHODS: To a tetrahydrofuran (THF, 10 mL) solution of N-fluorenylmethoxycarbonyl-L-alanine (10 mmol) was added a solution of N,N-diisopropylethylamine (DIPEA, 11 mmol, 1.42 mL) and a solution of ethyl acetate (EtOAc) (20 mmol, 6.36 mL) of 50% propylphosphonic anhydride (T3P) at 0 °C and stirred for about 10 min. Then sodium borohydride (NaBH4) aqueous solution (10 mmol, 388 mg, dissolved in 0.3 mL of water) was slowly added to the reaction mixture at the same temperature, and the progress of the reaction was monitored by thin layer chromatography (TLC) until the reaction was completed. Upon completion of the reaction, the solvent was removed by evaporation under reduced pressure, and the crude product was extracted with ethyl acetate (EtOAc), and the organic phase was washed sequentially with 5% aqueous citric acid (10 mL x 2), 5% aqueous sodium carbonate (Na2CO3) (10 mL x 2), water and saturated saline. The organic phase was dried over anhydrous sodium sulfate (Na2SO4) and the solvent was evaporated under reduced pressure to obtain the target product, N-fluorenylmethoxycarbonyl-L-alaninol.