Acetic Acid → Ethyl [4-oxo-1-{[(7S)-2'-oxo-1',2',6,8-tetrahydrospiro[cyclopenta[g]quinoline-7,3'-pyrrolo[2,3-b]pyridin]-2-yl]methyl}-1,2,4,5-tetrahydropyrrolo[4,3,2-de]quinolin-2a(3H)-yl]acetate

Participants

Reaction Steps

To a stirred solution of (S)-2′-oxo-1′,2′,6,8-tetrahydrospiro[cyclopenta[g]quinoline-7,3′-pyrrolo[2,3-b]pyridine]-2-carbaldehyde (339 mg, 1.08 mmol, described in Intermediate 10), ethyl (4-oxo-1,2,4,5-tetrahydropyrrolo[4,3,2-de]quinolin-2a(3H)-yl)acetate, enantiomer A (200 mg, 0.768 mmol, described in Intermediate 22), and AcOH (0.44 mL, 7.68 mmol) in DCE (5 mL) was added sodium triacetoxyborohydride (228 mg, 1.08 mmol) and the mixture was stirred for 90 min at ambient temperature. The reaction mixture was partitioned between saturated aqueous NaHCO3 (20 mL) and CH2Cl2 (20 mL). The organic layer was removed and the aqueous layer was extracted further with CH2Cl2 (3×20 mL). The combined organic extracts were washed with brine (10 mL), dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography, eluting with a gradient of CH2Cl2:MeOH—100:0 to 95:5, to give the title compound. MS: m/z=560 (M+1). HRMS: m/z=560.2303; calculated m/z=560.2293 for C33H30N5O4.

Provenance & Evidence