Hydrochloric Acid → 4-(4-(7-(4-Cyano-3-(trifluoromethyl)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3,4]octan-5-yl)phenyl)-N,N-dimethylbutanamide

Participants

Reaction Steps

A mixture of N,N-Dimethyl 4-[4-(1-cyanocyclobutylamino)phenyl]butanamide (Formula 48) (58 mg, 0.20 mmol) and 4-isothiocyanato-2-trifluoromethyl benzonitrile (74 mg, 0.32 mmol) in DMF (3 mL) was heated under reflux for 2 hours. To this mixture was added methanol (20 mL) and aq. 1 N HCl (5 mL). The second mixture was refluxed for 1.5 h. After being cooled to room temperature, the reaction mixture was poured into cold water (50 mL) and extracted with ethyl acetate (50 mL). The organic layer was dried over MgSO4, concentrated and the residue was purified with silica gel column chromatography (dichloromethane:acetone, 95:5) to give 4-(4-(7-(4-Cyano-3-(trifluoromethyl)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-5-yl)phenyl)-N,N-dimethylbutanamide, RD169 (Formula 49) (44 mg, 42%) as a pale yellowish solid. 1H NMR δ 7.98 (s, 1H), 7.97 (d, 1H, J=8.2 Hz), 7.86 (d, 1H, J=8.2 Hz), 7.42 (d, 2H, J=8.3 Hz), 7.22 (d, 2H, J=8.3 Hz), 2.99 (s, 3H), 2.96 (s, 3H), 2.78 (t, 2H, J=7.5 Hz), 2.62-2.70 (m, 2H), 2.52-2.63 (m, 2H), 2.40 (t, 2H, J=7.5 Hz), 2.15-2.30 (m, 1H), 2.04 (p, 2H, J=7.5 Hz), 1.62-1.73 (m, 1H).

Provenance & Evidence