Lithium Hydroxide → 5-({3-[(3R,4S)-3-Hydroxytetrahydro-2H-pyran-4-yl]-4-oxo-3,4-dihydrobenzo[h]quinazolin-6-yl}methyl)pyridine-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 5-({3-[(3R,4S)-3-hydroxytetrahydro-2H-pyran-4-yl]-4-oxo-3,4-dihydrobenzo[h]quinazolin-6-yl}methyl)pyridine-2-carboxylate (0.150 g, 0.337 mmol) in 2 mL of water and 2 mL of THF was added lithium hydroxide (0.016 g, 0.67 mmol). The mixture was heated to 50° C. for 2 h, cooled to rt, and quenched with saturated aqueous potassium phosphate to pH 5. The aqueous solution was extracted 3× with ethyl acetate and the combined organic fractions were dried over sodium sulfate, filtered, and concentrated in vacuo to provide the title compound that gave proton NMR spectra consistent with theory and a mass ion (ES+) of 432.1560 for [M+H]+ [Calc'd for C24H22N3O5, [M+H]+=432.1554]: 1H NMR (400 MHz, CDCl3) δ 896-8.94 (m, 1H), 8.70 (s, 1H), 8.67 (s, 1H), 8.13-8.10 (m, 1H), 7.98 (s, 1H), 8.89 (d, J=8.2 Hz, 1H), 7.78-7.67 (m, 3H), 5.26 (d, J=5.3 Hz, 1H), 4.63 (s, 2H), 4.14-4.03 (m, 1H), 3.94-3.88 (m, 2H), 3.41 (t, J=11.0 Hz, 1H), 3.27 (br s, 1H), 3.12-3.08 (m, 2H), 2.28-2.19 (m, 1H), 1.87-1.83 (m, 1H).

Provenance & Evidence