Triphenylphosphine (1.31 g, 5.00 mmol), tetrahydrofuran (4.00 mL), 3-N,N-dimethylaminopropanol (0.592 mL, 5.00 mmol) and diethylazodicarboxylate (0.788 mL, 5.00 mmol) were added to 3-(3-hydroxyphenyl)-1-perhydro-2H-pyran-2-yl-1H-indazole-5-carbonitrile 3-(3-hydroxyphenyl)-1-perhydro-2H-pyran-2-yl-1H-indazole-5-carbonitrile (0.400 g, 1.25 mmol). The mixture was stirred at ambient temperature for 15.5 h and poured into aqueous 6 N hydrochloric acid (30 mL). After stirring at ambient temperature for 4 h, the mixture was extracted with ethyl acetate (3×). The aqueous fraction was added to aqueous 6 N sodium hydroxide (30 mL) and the pH adjusted to 11. The solution was extracted with ethyl acetate (3×) and the organic fractions were combined and dried over anhydrous sodium sulfate, filtered and evaporated. Purification by flash chromatography on silica gel pretreated with 2% triethylamine/hexanes followed by 0-20% ethyl acetate/hexanes elution, sonication of the product in ethyl acetate (3 mL), addition of hexanes (20 mL) and filtration gave the title compound (0.225 g, 56% yield). ES-MS (m/z) 321 [M+1]+.
