Dicyclohexylcarbodiimide → HCID 54421670, compound

Participants

Reaction Steps

2-Trimethylsilylethyl (2R,4R)-3-{3-{2-[4-tertbutoxycarbonyl]-2-(2-fluorophenyl)-3-thiazolidinyl]-2-oxoethyl}ureido}benzoate may be prepared in a fashion similar to that described in Example 41 §A, but starting from 3.35 g of tert-butyl (2RS,4R)-2-(2-fluorophenyl)-4-thiazolidinecarboxylate, 4.0 g of 2-{3-[3-(2-trimethylsilylethoxycarbonyl)phenyl]ureido}acetic acid and 2.45 g of N,N'-dicyclohexylcarbodiimide. The crude product is purified by chromatography on silica [eluent: ethyl acetate/cyclohexane (30/70 by volume)]. The fractions containing the expected product are combined and concentrated to dryness under reduced pressure at 40° C. 2.4 g of 2-trimethylsilylethyl (2R,4R)-3-{3-{2-[4-tert-butoxycarbonyl-2-(2-fluorophenyl)-3-thiazolidinyl]-2-oxoethyl}ureido}benzoate are thus obtained in the form of an amorphous beige solid, used as it is in subsequent syntheses ([α]D20 =±50.2°+1.6° (C=0.38%; CHCl3))

Provenance & Evidence