反应详情

5.00 Grams of H-Leu-OEt.HCl, 5.95 g of Boc-Asn-OH and 4.11 g of HOBT.H2O were suspended in 100 ml of THF. To this suspension was added 4.70 ml of WSC with ice-cooling. The mixture was stirred for 7 hours at room temperature. To the reaction mixture were added 100 ml of ethyl acetate and 200 ml of water to effect extraction. The ethyl acetate layer was washed with 50 ml of a saturated aqueous sodium bicarbonate solution three times, 50 ml of a saturated aqueous sodium chloride solution once, 50 ml of 1N hydrochloric acid three times and 50 ml of a saturated aqueous sodium chloride solution once in this order, dried with anhydrous magnesium sulfate and concentrated under reduced pressure. The residue was solidified with isopropyl ether to obtain 7.00 g (yield: 72.9%) of the above objective compound. Melting point: 155°-157° C.

1. temperaturecooling
2. extractionextraction
3. washThe ethyl acetate layer was washed with 50 ml of a saturated aqueous sodium bicarbonate solution three times, 50 ml of a saturated aqueous sodium chloride solution once
4. dry with material50 ml of 1N hydrochloric acid three times and 50 ml of a saturated aqueous sodium chloride solution once in this order, dried with anhydrous magnesium sulfate
5. concentrationconcentrated under reduced pressure