Hydrochloric Acid → HCID 178427589, compound

Participants

Reaction Conditions

Reaction Steps

At 0° C. the solution of 72 mg (0.231 mmol) of HCl.Pro-Ala-OBzl in 15 ml of anhydrous tetrahydrofuran was adjusted to pH 9, to which the pre-cold solution of 100 mg (0.234 mmol) of Boc-Arg(Tos)-OH, 31 mg (0.230 mmol) of 1-hydroxybenzotriazole and 48 mg (0.233 mmol) of dicyclohexylcarbodiimide in 20 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, 30:1) indicated complete disappearance of HCl.Pro-Ala-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 120 mg (75.6%) of the title compound as a colorless powder. Mp70–71.5° C., FAB-MS (m/e) 688[M+H]+.

Provenance & Evidence