反应详情

To a solution of 1-5 (150 mg, 0.39 mmol), HOBT (63 mg, 0.46 mmol) and EDC (111 mg, 0.58 mmol) was added 3(S)-(ethynyl)-β-alanine ethyl ester hydrochloride (1-32) (U.S. Pat. No. 5,272,162; 82 mg, 0.46 mmol) and Et3N (80.7 gl, 0.58 mmol). The mixture was stirred at room temperature under argon for 16 hours and then partitioned between EtOAc and 10% citric acid. The aqueous phase was extracted with EtOAc (x3) and the combined organic layers then washed with saturated aqueous NaHCO3 followed by brine. Removal of the dried (MgSO4) solvent afforded a yellow oil which was purified by column chromatography (silica gel; hexane/EtOAc 1:1) to give 1-33 as an oil. Rf (silica; EtOAc/hexane 2:1) 0.57 ##STR51##

1. custompartitioned between EtOAc and 10% citric acid
2. extractionThe aqueous phase was extracted with EtOAc (x3)
3. washthe combined organic layers then washed with saturated aqueous NaHCO3
4. customRemoval of the
5. dry with materialdried (MgSO4) solvent
6. customafforded a yellow oil which
7. customwas purified by column chromatography (silica gel; hexane/EtOAc 1:1)