4-Hydroxybenzaldehyde → HCID 178438020, compound

Participants

Reaction Conditions

Reaction Steps

2-[3,4-bis(methyloxy)phenyl]-3-oxopentanenitrile (100 mg, 0.43 mmol) was dissolved in ethanol (1 mL), and anhydrous hydrazine (98%, 16 μL, 0.52 mmol) was added. The resulting mixture was heated at reflux for 1 hour. It was cooled, concentrated, and the residue was dried in vacuum for one hour. To this residue was added of 4-hydroxybenzaldehyde (79 mg, 0.64 mmol) and trifluoroacetic acid (1 mL), and the mixture was heated at 70° C. for 18 hours. Then the reaction mixture was concentrated, dissolved in 10 mL of N,N-dimethylformamide and purified by preparatory HPLC (Shimadzu LC-8A HPLC, Waters Xterra C18 30 mm×100 mm column, acetonitrile-water-trifluoroacetic eluent). After concentration then lyophillization of the pure fractions 4-[1-ethyl-7,8-bis(methyloxy)-3H-pyrazolo[3,4-c]isoquinolin-5-yl]phenol trifluoroacetic acid salt (55 mg, 0.12 mmol, 28% yield) was obtained. 1H NMR (400 MHz, d6-DMSO): 7.77 (s, 1H), 7.71-7.69 (d, 2H), 7.51 (s, 1H), 7.01-6.98 (d, 2H), 4.05 (s, 3H), 3.76 (s, 3H), 3.26-3.21 (q, 2H), 1.44-1.40 (t, 3H); MS (EI) for C20H19N3O3: 349 (MH+).

Provenance & Evidence