反应详情

A mixture of 313 mg 1.18 mmol) of t-butoxycarbonyl-L-phenylalanine. 460 mg (1.18 mmol) of (S)-α-amino-N-[(1S,2S,4S)-1-(cyclohexylmethyl)-2-hydroxy-4-isopropyl-5-hexenyl]imidazole-4-propionamide, 0.15 ml (1.18 mmol) of 4-ethylmorpholine, 320 mg (2.36 mmol) of HOBT and 292 mg (1.42 mmol) of DCC in 20 ml of dimethylformamide was stirred at room temperature overnight. Thereafter, the separated precipitate was filtered off and the solvent was evaporated in a high vacuum. The residue was dissolved in ethyl acetate and then washed in succession with 2N sodium bicarbonate solution, saturated ammonium chloride solution, again with 2N sodium bicarbonate solution and again with saturated ammonium chloride solution. After drying the organic solution over sodium sulfate, the solvent was evaporated under reduced pressure and, for purification, the residue (870 mg) was chromatographed on 30 g of silica gel using a 20:1:0.1 mixture of methylene chloride, methanol and ammonia as the eluting agent. Crystallization of the thus-obtained crude product from methylene chloride/ether yielded 410 mg of t-butyl [(S)-α-[[(S)-1-[[(1S,2S,4S)-1-(cyclohexylmethyl)-2-hydroxy-4-isopropyl-5-hexenyl]carbamoyl]-2-imidazol-4-ylethyl]-carbamoyl]phenethyl]carbamate, melting point 161°.

1. filtrationThereafter, the separated precipitate was filtered off
2. customthe solvent was evaporated in a high vacuum
3. dissolutionThe residue was dissolved in ethyl acetate
4. washwashed in succession with 2N sodium bicarbonate solution, saturated ammonium chloride solution, again with 2N sodium bicarbonate solution and again with saturated ammonium chloride solution
5. dry with materialAfter drying the organic solution over sodium sulfate
6. customthe solvent was evaporated under reduced pressure and, for purification
7. customthe residue (870 mg) was chromatographed on 30 g of silica gel using
8. additiona 20:1:0.1 mixture of methylene chloride, methanol and ammonia as the eluting agent
9. customCrystallization of the
10. customthus-obtained crude product from methylene chloride/ether