反应详情

A solution of 2.1 g of N-[(S,S)-2,4-dibenzyl-4-carboxybutyryl]-S-benzyl-(L)-cysteine methyl ester, 0.60 g of 2-aminopyridine and 1.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride in 25 ml of methylene chloride is stirred at room temperature overnight. The mixture is concentrated, ethyl acetate is added and washed with water, sodium bicarbonate, dried (Na2SO4), filtered and concentrated. The residue is chromatographed on silica gel eluting with ethyl acetatemethylene chloride (1:9) to give N-[4-(2-pyridylamino-carbonyl)-(S,S)-2,4-dibenzylbutyryl]-S-benzyl-(L)-cysteine methyl ester (oil).

1. concentrationThe mixture is concentrated
2. additionethyl acetate is added
3. washwashed with water, sodium bicarbonate
4. dry with materialdried (Na2SO4)
5. filtrationfiltered
6. concentrationconcentrated
7. customThe residue is chromatographed on silica gel eluting with ethyl acetatemethylene chloride (1:9)