反应详情

Prepared according to the method described in Example 1(d) above from (R)-N5 -(Cbz)-(S)-N-[2-hydroxy-1-(4-methoxyphenyl)ethyl]ornithine amide hydrochloride (2.32 g, 5.13 mmol; from step (b) above), 2-nitrophenyl diphenyl acetate (1.81 g; 5.65 mmol; see Example 1(c) above), triethylamine (0.78 g, 7.70 mmol) and CH2Cl2 (150 mL), 60 hours reaction time. The reaction mixture was submitted to aqueous work up, dried, filtered and concentrated to give the crude product as an off-white solid (3.39 g). The crude product was chromatographed on silica gel eluting with CH2C2 :MeOH (98:2). Concentration of the appropriate fractions gave pure sub-title compound as a white solid (2.85 g).

1. customPrepared
2. customdried
3. filtrationfiltered
4. concentrationconcentrated
5. customto give the crude product as an off-white solid (3.39 g)
6. customThe crude product was chromatographed on silica gel eluting with CH2C2