To a solution of (S)-methyl 3-(6-(3-(1,4-dioxaspiro[4.5]decan-2-yl)-1,2,4-thiadiazol-5-ylamino)-5-(2-methylpyridin-3-yloxy)pyridin-3-ylthio)propanoate (0.428 g, 0.787 mmol) in THF (20 mL) was added potassium 2-methylpropan-2-olate (1M in THF, 2.36 ml, 2.36 mmol) and the reaction was stirred at ambient temperature for 5 minutes. (Bromomethyl)cyclopropane (0.106 g, 0.787 mmol) was added followed by DMF (5 mL) and the reaction was stirred for 1 hour at ambient temperature. The reaction was poured into EtOAc (500 mL) and the organic layer was washed with a 1:1 solution of water, 1N NaOH (100 mL total) and brine, dried over MgSO4 and concentrated in vacuo. The residue was purified over silica gel (40% EtOAc/CH2Cl2) to afford (S)—N-(5-(cyclopropylmethylthio)-3-(2-methylpyridin-3-yloxy)pyridin-2-yl)-3-(1,4-dioxaspiro[4.5]decan-2-yl)-1,2,4-thiadiazol-5-amine (0.30 g, 0.586 mmol, 74.5% yield).
