Hydrochloric Acid → HCID 131726071, compound

Participants

Reaction Conditions

Reaction Steps

At 0° C. the solution of 657 mg (1.28 mmol) of HCl.Ala-Lys(ClZ)-OBzl in 5 ml of anhydrous tetrahydrofuran was adjusted to pH 9, to which the pre-cold solution of 280 mg (1.3 mmol) of Boc-Pro-OH, 170 mg (1.26 mmol) of 1-hydroxybenzotriazole and 270 mg (1.31 mmol) of dicyclohexylcarbodiimide in 30 ml of anhydrous tetrahydrofuran was added. The reaction mixture was stirred at 0° C. for 2 h and at room temperature for 6 h and TLC (chloroform/methanol, 20:1) indicated complete disappearance of HCl.Ala-Lys(ClZ)-OBzl. The resulted precipitates of N,N-dicyclohexylurea were filtrated and the filtrate was diluted with 80 ml of ethyl acetate. The solution obtained was washed successively with saturated NaCO3 in water (50 ml×3), saturated NaCl in water (50 ml×3) and KHSO4 in water (5%, 30 ml×3). The separated ethyl acetate layer was dried with anhydrous MgSO4, and then evaporated to provide 134 mg (98%) of the title compound as a colorless powder. Mp86–88° C., FAB-MS (m/e) 674[M+H]+.

Provenance & Evidence