Hydrochloric Acid → 2-(5-[(1S)-1-benzyloxycarbonylamino-ethyl]-3-benzyl-2-oxo-cyclohept-4-en-1-yl)-1-oxo-ethyl-valinyl-valine methyl ester

Participants

Reaction Steps

To a stirred solution of the above acid (37) (1.0 g) in dimethylformamide (20 mL) was added hydroxybenzotriazole (0.62 g), HCl.Val-Val-OMe (0.67 g), triethylamine (1.93 mL) followed by Bop reagent (1.93 g). After stirring at room temperature for 16 h the reaction was evaporated to dryness and flash chromatographed on silica gel eluted with 60% ethyl acetate in n-hexane to give the titled product (38) (0.95 g, 57%). TLC Rf 0.48, 0.41 (60% ethyl acetate, n-hexane) Rf 0.40, 0.37 (97:3 CHCl3 :MeOH); MS DCI/NH3 (M+H)+ =648.5; 1H NMR (CDCl3) δ0.8-1.0(12H, m) Val γ(CH3)2 's, 1.12(3H, d, J=7 Hz) Ala CH3, 3.7(3H, s) CO2CH3, 5.1(2H, s) Cbz CH2, 5.4(1H, d) vinyl CH, 7.22(5H, s) phenyl, 7.46(5H, s) Cbz phenyl.

Provenance & Evidence