Triphenylphosphine → 5-(5-(3-Fluoro-4-(2-(pyrrolidin-1-yl)ethoxy)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-7-yl)-3-(trifluoromethyl)picolinonitrile

Participants

Reaction Steps

A mixture of 5-(5-(3-fluoro-4-hydroxyphenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-7-yl)-3-(trifluoromethyl)picolinonitrile (Compound 1, 100 mg, 0.23 mmol), 2-(pyrrolidin-1-yl)ethanol (35 μL, 0.30 mmol), triphenylphosphine (79 mg, 0.30 mmol), and diisopropyl azodicarboxylate (60 μL, 0.30 mmol) in THF (5 mL) was stirred at room temperature for 2 days. The reaction mixture was absorbed on silica gel and purified by column chromatography on silica gel eluting with 0 to 10% MeOH/DCM to afford impure desired product that was repurified by reverse phase HPLC (acetonitrile/water, 0.1% TFA). The fractions containing the desired compound were combined, acetonitrile was removed in vacuo, and the remaining aqueous layer was treated with a saturated solution of sodium bicarbonate. The aqueous layer was extracted with DCM (3×), the organics were combined, dried over sodium sulfate, and evaporated to dryness to afford 30 mg of 5-(5-(3-fluoro-4-(2-(pyrrolidin-1-yl)ethoxy)phenyl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]octan-7-yl)-3-(trifluoromethyl)picolinonitrile as a white solid. 1H NMR (300 MHz, DMSO-d6) δ 9.21 (d, 1H), 8.74 (d, 1H), 7.40 (t, 1H), 7.35 (dd, 1H), 7.22 (d, 1H), 4.24 (t, 2H), 2.86 (t, 2H), 2.65-2.42 (m, 8H), 1.98-1.95 (m, 1H), 1.70 (m, 4H), 1.60-1.54 (m, 1H). LCMS [M+1]+ 534.9.

Provenance & Evidence