Imidazole → N'-((2R,3S)-3-(tert-butyldimethylsilyloxy)-2-(3-chloro-4-cyano-2-methylphenylamino)butanoyl)-4-nitrobenzohydrazide

Participants

Reaction Conditions

Reaction Steps

N′-((2R,3R)-2-(3-chloro-4-cyano-2-methylphenylamino)-3-hydroxybutanoyl)-4-nitrobenzo-hydrazide (2.0 g, 4.63 mmol) was added to DMF (100 mL), followed by addition of TBDMS-Cl (1.74 g, 11.6 mmol) and imidazole (1.58 g, 23.2 mmol) at 0° C. The solution was allowed to stir at 0° C. for 30 minutes and then at room temperature for overnight. The reaction was quenched with the addition of 200 mL brine and extract with EtOAc. Purification by flash column chromatography [EtOAc-hexanes (1:1) as eluent] afforded the title compound as a white solid (780 mg, 82%). 1H NMR (400 MHz, 4-acetone, δ in ppm) 9.88 (br s, 2H), 8.35 (d, J=6.7 Hz, 2H), 8.16 (d, J=6.7 Hz, 2H), 7.53 (d, J=7.5 Hz, 1H), 6.69 (d, J=7.5 Hz, 1H), 5.56 (d, J=6.6 Hz, 1H), 4.46-4.36 (m, 1H), 4.18-4.10 (m, 1H), 3.26 (s, 3H), 1.37 (d, J=7.4 Hz, 3H), 0.94 (s, 9H), 0.14 (s, 3H), 0.11 (s, 3H).

Provenance & Evidence