Sodium 1.1-dimethylethyl 4-(3-bromo-8-chloro-6,11-dihydro-5H-benzo[5,6]cyclohepta[1,2-b]pyridin-11(S)-yl)-2(R)-carboxy-1-piperazinecarboxylate (prepared as described in Preparative Example 6 (sodium salt)) (0.1 g, 0.79 mmoles), 2-[2-(1H-imidazol- 1-yl)ethylpiperdidine (prepared as described in Preparative Example 57, Step D) (0.0417 g, 0.233 mmoles), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (0.0446 g, 0.233 mmoles), 1-hydroxybenzotriazole (0.0314 g, 0.233mmoles) and 4-methylmorpholine (0.0512 mL, 0.466 mmoles) were dissolved in anhydrous DMF (4 mL) and the mixture was stirred under argon at 25° C. for 42 h. The solution was evaporated to dryness and the residue was taken up in dichloromethane and washed with 1N NaOH, dried (MgSO4), filtered and evaporated to dryness. The residue was chromatographed on silica gel using 2.5%-4.5%-7.5% (10% conc. NH4OH in methanol)-dichloromethane as the eluant to give the title compound (0.0172 g, 14%): HRFABMS: m/z 697.2285 (MH+) (Calcd. m/z 697.2269); δH (CDCl3) 1.38/1.41 (9H, s, CH3), 4.31 (1H, s, H11), 4.68 (1H, bs, H2), 7.03-7.20 (5H, bm, Ar—H and Im-H4 and Im-H5), 7.57 (1H, Im-H2), 7.83/8.19 (s, Ar—H) and 8.38 ppm (1H, s, Ar—H2): δC (CDCl3) CH3: 28.4, 28.4, 28.4; CH2: 19.1, 24.8/24.9, 28.3, 30.3, 30.5, 31.4, 40.3, 42.9/43.2, 44.1/44.6, 45.6, 50.2/50.5; CH: 44.1/44.6, 52.4, 78.4, 119.2, 126.2, 127.9, 130.8/130.9, 132.6, 136.7, 141.6, 146.9/147.2: C: 80.4, 119.8/120.2, 134.4, 135.9, 137.0, 141.5, 155.0, 156.7/157.1, 170.3/170.9.
