反应详情

2-((3-benzyl-5-(4-hydroxyphenyl)pyrazin-2-yl)amino)pentanoic acid (49 mg, 0.13 mmol) was dissolved in DCM (10 mL). Pyridine (0.5 mL) was added followed by N,N′-Dicyclohexylcarbodiimide (54 mg, 0.26 mmol). The reaction mixture was slowly stirred at room temperature for 1 hr. The solvent was evaporated, and the residue purified by flash chromatography (eluting solvent: EtOAc to DCM to 10% methanol in DCM) to give the product as a yellow powder (40 mg, 86%). 1H NMR (300 MHz, CD3OD, δ): 7.35 (m, 8H), 6.88 (d, J=9.0 Hz, 2H), 4.40 (s, 2H), 2.81 (t, J=7.5 Hz, 2H), 1.81 (m, 2H), 1.02 (t, J=7.5 Hz, 3H); MS (ESI) m/z 359.0.

1. customThe solvent was evaporated
2. customthe residue purified by flash chromatography (eluting solvent: EtOAc to DCM to 10% methanol in DCM)