Water → ethyl 3-(3-(4-methoxybenzyl)-6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c][2,7]naphthyridine-7-carboxamido)benzoate

Participants

Reaction Steps

To a solution of 3-(4-methoxybenzyl)-6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c][2,7]naphthyridine (0.208 g, 0.707 mmol) in anhydrous dichloromethane (10 mL) was added 3-isocyanato-benzoic acid ethyl ester (0.135 g, 0.707 mmol). The reaction was then shaken at room temperature for 30 minutes. On completion of the reaction water (10 mL) was added and the organic layer was separated. The aqueous layer was extracted with dichloromethane (20 mL). The organic extracts were combined, washed with brine (2×20 mL), dried using sodium sulfate, filtered and concentrated under reduced pressure. The crude product was purified using flash column chromatography (SiO2, gradient from 50% EtOAc in hexanes to 66% EtOAc in hexane) to give the pure desired product, ethyl 3-(3-(4-methoxybenzyl)-6,7,8,9-tetrahydro-3H-pyrazolo[3,4-c][2,7]naphthyridine-7-carboxamido)benzoate (0.265 g, 77%) as a white solid. M.p.=>80° C.; 400 MHz 1H NMR (DMSO-d6) δ: 8.97 (s, 1H), 8.41 (s, 1H), 8.2 (s, 1H), 8.14-8.1 (m, 1H), 7.85-7.8 (m, 1H), 7.57-7.53 (m, 1H), 7.39 (t, J=7.6 Hz, 1H), 7.21-7.16 (m, 2H), 6.88-6.82 (m, 2H), 5.59 (s, 2H), 4.81 (s, 2H), 4.31 (q, J=7.2 Hz, 2H), 3.84 (t, J=6 Hz, 2H), 3.69 (s, 3H), 3.15 (t, J=6 Hz, 2H), 1.32 (t, J=7.2 Hz, 3H); LCMS [M+H]: 486.

Provenance & Evidence