Imidazole → HCID 54172470, compound

Participants

Reaction Steps

To a solution of 3.72 g (7.88 mmol) of the crude product of Example 21 dissolved in 10 mL of DMF was added 2.68 g (0.039 mol) of imidazole followed by 2.85 g (0.019 mol) of t-butyldimethylsilyl chloride. The reaction mixture was stirred at room temperature for 2 h and then poured into 200 mL of H2O. The resultIng solution was extracted with ether and the combined organic layers were washed with water and brine, dried over MgSO4, filtered and concentrated in vacuo. The residue was dissolved in 10 mL of methanol/THF (1:1) and 5.0 mL of 1N NaOH solution was added. After stirring for 0.75 h at room temperature the reaction mixture was acidified with 5% HCl solution to pH 5 and then extracted with ether. The combined organic layers were washed with water and brine, dried over MgSO4, filtered and concentrated in vacuo. The residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:10) to provide 4.76 g (100%) of the desired product as a colorless oil. Electrospray Mass Spec: 603.5 (M-H)-.

Provenance & Evidence