Hydrazinecarboxylic acid, ethyl ester → Tert-butyl(1-(4-(3-oxo-9-phenyl-2,3,5,6-tetrahydro-[1,2,4]triazolo[3,4-f][1,6]naphthyridin-8-yl)phenyl)cyclobutyl)carbamate

Participants

Reaction Steps

To a solution of tert-butyl(1-(4-(3-phenyl-5-thioxo-5,6,7,8-tetrahydro-1,6-naphthyridin-2-yl)phenyl)cyclobutyl)carbamate (55 mg, 0.113 mmol) in THF (7 mL) was added ethyl carbazate (23.6 mg, 0.226 mmol) and mercury acetate (54.1 mg, 0.17 mmol) under nitrogen. The resulting mixture was stirred at r.t. for 2 h. The mixture was concentrated to dryness under reduced pressure and partitioned between DCM (15 ml) and water (15 ml). The organic phase was separated and concentrated to dryness under reduced pressure. The resulting residue was suspended in toluene (7 ml). The resulting mixture was heated under reflux for 3 h. After cooled down to room temperature, the mixture was concentrated to dryness under reduced pressure. The resulting residue was purified by Biotage silica gel chromatography (gradient 0 to 4% MeOH in dichloromethane) to give tert-butyl(1-(4-(3-oxo-9-phenyl-2,3,5,6-tetrahydro-[1,2,4]triazolo[3,4-f][1,6]naphthyridin-8-yl)phenyl)cyclobutyl)carbamate (32 mg, 56%). LCMS (Method A): RT=6.29 min, M+1=510. 1H NMR (500 MHz, CDCl3): 9.83 (1H,S), 8.10 (1H, s), 7.29 (2H, d), 7.22 (2H, d), 7.19-7.18 (3H, m), 7.13-7.11 (2H, m), 5.1 (1H, br), 4.01 (2H, t), 3.36 (2H, t), 2.43-2.28 (4H, m), 2.02-1.97 (1H, m), 1.76-1.70 (1H, m), 1.30-1.14 (9H, br).

Provenance & Evidence