Tetrahydrofuran → 7-{2-[3-(2-Carboxy-ethyl)-benzo[b]thiophen-6-yloxy]-ethyl}-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

7-{2-[3-(2-Ethoxycarbonyl-ethyl)-benzo[b]thiophen-6-yloxy]-ethyl}-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid tert-butyl ester (338 mg, 0.66 mmol) was dissolved THF (5ml). Then a solution of sodium hydroxide (132 mg, 3.30 mmol) in water (1 ml) was added. The reaction was stirred at room temperature for 16 hours. After that period, the solvent was evaporated under vacuum and the crude was extracted with ethyl acetate and hydrochloric acid (1M). The organic layer was collected, dried with anhydrous sodium sulfated, filtrated and evaporated under vacuum to yield 268 mg (84%) of 7-{2-[3-(2-Carboxy-ethyl)-benzo[b]thiophen-6-yloxy]-ethyl}-3,4-dihydro-2H-[1,8]naphthyridine-1-carboxylic acid tert-butyl ester. NMR 1H Cl3CD δ: 7.59 (d, 1H, J=8.8 Hz), 7.47 (d, 1H, J=7.7 Hz), 7.35 (d, 1H, J=2.3 Hz), 7.05 (d, 1H, J=7.6 Hz), 7.01 (s, 1H), 6.96 (dd, 1H, J=2.3, 8.8 Hz), 4.35 (t, 2H, J=6.5 Hz), 3.73 (m, 2H), 3.18 (m, 2H), 3.05 (m, 2H), 2.72 (m, 2H), 2.66 (m, 2H), 1.88 (m, 2H), 1.49 (s, 9H).

Provenance & Evidence