Phenylhydrazine → HCID 46182725, compound

Participants

Reaction Conditions

Reaction Steps

Following the general methods as outlined in Example 7, starting from phenylhydrazine, dimethyl 3-oxopentanedioate, 1,1,1-triethoxyethane, 3-aminomethylpyridine and acylation of the corresponding intermediate compound according to Formula (Ia) the following procedure was used: to a solution of 4-methyl-1-(4-phenoxybutanoyl)-2-phenyl-5-(pyridin-3-ylmethyl)-1H-pyrazolo[4,3-c]pyridine-3,6(2H,5H)-dione (4) (Compound Ib, Scheme 1) (0.100 g, 0.301 mmol, 1 equiv.) in 3.2 mL of DMF was added dropwise iPrNEt2 (0.058 mL, 0.331 mmol, 1.1 equiv.) at 0° C. under a N2 atmosphere. The resulting mixture was stirred at 0° C. to give a red solution that was treated with 3-methoxyphenyl-acetyl chloride (0.061 g, 0.331 mmol, 1.1 equiv.) and allowed to come back to rt. After 30 min at rt, iPrNEt2 (0.058 mL, 0.331 mmol, 1.1 equiv.) was added and the reaction mixture was partitioned into EtOAc/water. Extractive workup was followed by drying of the organic phase over Na2SO4 and concentration in vacuo. The resulting residue was purified by flash chromatography over SiO2 (CH2Cl2:MeOH, 97:3) to give the titled compound as a beige solid (0.077 g, 53% yield). 1H NMR (500 MHz, CDCl3) 2.79 (s, 3H), 3.74 (s, 3H), 5.40 (s, 2H), 6.52 (s, 1H), 6.56 (d, J 7.6 Hz, 1H), 6.77 (dd, J 8.2, 1.6 Hz, 1H), 7.16 (m, 2H), 7.28 (m, 1H), 7.34 (m, 1H), 7.50-7.45 (m, 4H), 7.57 (d, J=7.9 Hz, 1H), 8.55 (m, 2H); MS (ESI+): 481.6; MS (ESI−): 479.3.

Provenance & Evidence