Hydrochloric Acid → (S)-8-((2-amino-4-methylpentyl)oxy)-6,9-dimethylbenzo[c][2,7]naphthyridin-5(6H)-one

Participants

Reaction Conditions

Reaction Steps

In a 25 mL round-bottomed flask, (S)-tert-butyl (1-((6,9-dimethyl-5-oxo-5,6-dihydrobenzo[c][2,7]naphthyridin-8-yl)oxy)-4-methylpentan-2-yl)carbamate (80 mg, 0.182 mmol) was taken in MeOH (6 mL). The reaction mixture was cooled to 0° C. and a 4M solution of HCl in 1,4-dioxane (3.75 mL, 12 mmol) was added and the mixture stirred at RT for 2 h. The MeOH was removed and the crude product was dissolved in ethyl acetate (20 mL). The ethyl acetate layer was washed with water (10 mL) and dried over sodium sulfate. Removal of the solvent gave crude product which was purified by silica-gel column (MeOH—CHCl3 mixture) to afford (S)-8-((2-amino-4-methylpentyl)oxy)-6,9-dimethylbenzo[c][2,7]naphthyridin-5(6H)-one (0.03 g, 0.09 mmol, 49% yield) as yellow solid. LC/MS (ESI) m/e 340.2 [(M+H)+, calcd for C20H26N3O2, 340.4]; LC/MS retention time (method B): tR=1.33 min. HPLC retention time (method A): tR=8.58 min; HPLC retention time (method B): tR=8.12 min. 1H NMR (400 MHz, CD3OD) δ ppm 9.51 (s, 1H), 8.79 (d, J=6.02 Hz, 1H), 8.40 (d, J=5.77 Hz, 1H), 8.33 (s, 1H), 7.10 (s, 1H), 4.50 (dd, J=10.67, 3.14 Hz, 1H), 4.36 (dd, J=10.67, 5.90 Hz, 1H), 3.77-3.87 (m, 4H), 2.46 (s, 3H), 1.79-1.92 (m, 2H), 1.66-1.77 (m, 1H), 1.08 (dd, J=6.27, 4.02 Hz, 6H).

Provenance & Evidence