A solution of 5-cyano-3-(3-pyridyl)-1-(4′-aminophenyl)pyrazole (185 mg, 0.7 mmol) and indane 2-carboxaldehyde (0.96 mmol, 140 mg) in methanol (9 mL) and acetic acid (1 mL) was stirred at room temp for 30 min. Sodium cyanoborohydride (124 mg, 2 mmol) was added and stirring continued at room temperature. After 3 h the solvent was evaporated under vacuum, and the residue was taken up in sodium bicarbonate solution (50 mL) and extracted with methylene chloride (3×50 mL). The combined extract was washed with water, dried over anhydrous sodium sulfate and evaporated. Chromatography of the residue over silica gel (eluant, 15% ethyl acetate in methylene chloride) gave the title compound as a cream colored solid, m.p. 156-158° C. 1H NMR (DMSO-d6): δ 2.68-2.82 (3H, m), 3.05-3.15 (4H, m), 6.36-6.42 (1H, br. t), 6.75-6.77 (2H, d, J=8.9 Hz), 7.09-7.15 (2H, m), 7.21-7.24 (4H, m), 7.45-7.47 (2H, d, J=8.8 Hz), 7.51-7.54 (1H, m), 7.98 (1H, s), 8.21-8.28 (1H, br. d.), 8.6-8.62 (1H, br. d.), 9.1 (1H, d, J=1.9 Hz).
