To a solution of 1-{[3-({[(7,5)-2′-oxo-1′,2′,6,8-tetrahydrospiro[cyclopenta[g]quinoline-7,3′-pyrrolo[2,3-b]pyridin]-3-yl]methyl}amino)-2-phenylpropyl]-amino}cyclopentanecarboxylic acid from Step F (30 mg, 0.053 mmol) and HOBt (8.2 mg, 0.053 mmol) in THF (1 mL) were added EDCI (13.3 mg, 0.069 mmol) and triethylamine (19 μL, 0.14 mmol). This solution was stirred at ambient temperature for 18 h. The solution was then concentrated to yield a residue, which was applied to a silica gel column for purification, eluting with a gradient of 1-7% methanol in DCM. Concentration of the fractions containing the product provided the title compound. MS: m/z=544 (M+1). HRMS: m/z=544.2708, calculated m/z=544.2707 for C34H34N5O2.
