Trifluoroacetic acid → N-ethyl-N-[(2R)-2-(thiazol-5-ylmethoxycarbonylamino)-3-phenylpropyl]-N-[(2S)-2-(thiazol-5-ylmethoxycarbonylamino)-3-phenylpropyl]amine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

The product from Example 71B (86 mg, 0.17 mmol) in dichloromethane (1.8 mL) was treated with trifluoroacetic acid (1.0 mL) at ambient temperature. After stirring for 2 hours, the mixture was concentrated and treated with aqueous 10% K2CO3 (2.4 mL). The aqueous mixture was extracted with ethyl acetate (3×3 mL). The ethyl acetate extracts were combined and treated with 4-nitrophenyl 1,3-thiazol-5-ylmethyl carbonate [prepared from 4-nitrophenyl 1,3-thiazol-5-ylmethyl carbonate hydrochloride salt (99 mg, 0.35 mmol) by extraction with aqueous NaHCO3] in ethyl acetate (6 mL). After heat at 60° C. for 18 hours, the mixture was allowed to cool to ambient temperature and was concentrated. The residue was purified by flash column chromatography on silica gel eluting with (chloroform:methanol, 98:2) to provide the title compound (34.1 mg, 32%). 1H NMR (CDCl3) δ 8.78 (s, 2H), 7.85 (s, 2H), 7.32-7.05 (m, 10H), 5.40-5.17 (m, 6H), 4.20 (br s, 2H), 3.49-2.55 (m, 10H), 0.85 (t, 3H); MS (ESI+) m/z 594 (M+H)+.

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