Hydrochloric Acid → HCID 66833399, compound

Participants

Reaction Steps

2-Amino-2-[2-(4-benzylpiperidin-1-yl)ethyl]-6-borono-hexanoic acid dihydrochloride is prepared in a manner analogous to that set forth in Example 16, except 4-benzylpiperidine is used as the amine in step 6. The final step is as follows: a solution of 2-[2-(4-benzylpiperidin-1-yl)ethyl]-2-tert-butoxycarbonylamino-6-(4,4,5,5-tetramethyl-[1,3,2]-dioxa-borolan-2-yl)-hexanoic acid ethyl ester (95 mg) in 6 N hydrochloric acid (5 mL) was stirred at 95° C. overnight. After cooling to room temperature, the reaction mixture was transferred to a separatory funnel, diluted with deionized water (5 mL) and washed with dichloromethane (3×). The aqueous layer was frozen in liquid nitrogen and lyophilized to give the title compound as a colorless foam (42 mg); 1H NMR (D2O, 300 MHz) δ 7.24 (m, 2H), 7.13 (m, 3H), 3.42 (m, 2H), 3.18 (m, 1H), 3.00 (m, 1H), 2.78 (m, 2H), 2.44 (d, J=7.0 Hz, 2H), 2.16 (t, J=7.0 Hz, 2H), 1.76 (m, 5H), 1.24 (m, 5H), 1.09 (m, 1H) and 0.61 (t, J=7.0 Hz, 2H); MS (+CI): m/z for C20H33BN2O4: expected 376.3. found 377.2 (M+H)+, 359.2 (M+H−H2O)+.

Provenance & Evidence