Triethylamine → 1-[4-(3-acetyl-6-bromo-1-oxo-4-phenyl-1H-isoquinolin-2-ylmethyl)benzenesulfonyl]piperidine-4-carboxylic Acid Ethyl Ester

Participants

Reaction Steps

[Step 3] To a solution of 3-acetyl-6-bromo-4-phenylisochromen-1-one (343 mg) in methanol (20 ml) were added 1-(4-aminomethylbenzenesulfonyl)piperidine-4-carboxylic acid ethyl ester (979 mg) and triethylamine (1.4 ml), and the mixture was stirred at room temperature for 72 hrs. The solvent was evaporated under reduced pressure, and partitioned between 1N hydrochloric acid and ethyl acetate. The ethyl acetate layer was washed with saturated brine and dried by adding sodium sulfate. The solvent was evaporated under reduced pressure, 4N hydrochloric acid ethyl acetate solution (5 ml) was added to the obtained residue, and the mixture was stirred at room temperature for 10 hrs. The solvent was evaporated under reduced pressure, water was added and the mixture was extracted with ethyl acetate. The extract was washed with saturated sodium hydrogen carbonate solution and saturated brine and dried by adding sodium sulfate. The obtained residue was purified by silica gel column chromatography (n-hexane/ethyl acetate=7/3→2/3) to give the title compound (91 mg, 14%). 1H-NMR (CDCl3) δ: 1.21 (3H, t, J=7.0 Hz), 1.37 (3H, s), 1.65-2.01 (4H, m), 2.11 (1H, m), 2.38-2.56 (2H, m), 3.50-3.66 (2H, m), 4.09 (2H, q, J=7.0 Hz), 5.47 (2H, s), 7.24-7.50 (8H, m), 7.67-7.76 (3H, m), 8.41 (1H, d, J=8.4 Hz).

Provenance & Evidence