To a solution of 2-((3S,5R,6S)-5-(3-chlorophenyl)-6-(4-chlorophenyl)-1-(cyclopropylmethyl)-2-oxopiperidin-3-yl)acetic acid (Example 41) (83 mg, 0.192 mmol), methanesulfonamide (22.59 mg, 0.230 mmol) and 4-dimethylaminopyridine (1.057 mg, 0.00865 mmol) in DCM (2 mL) was added diisopropylethylamine (80 μL, 0.461 mmol). The reaction mixture was stirred at room temperature for one minute before adding bromo-tris-pyrrolidino-phosphonium hexafluorophosphate (125 mg, 0.269 mmol). The reaction mixture was stirred at room temperature for 3 hours. The reaction was quenched with 1N HCl and the aqueuos layer was extracted with DCM (10 mL). The combined organic layers were washed with 1N HCl, 1N NaOH, sat. aq. NaCl solution and concentrated under reduced pressure. The residue was purified by reversed phase preparatory HPLC (column: Gemini-NX C18 5 μm column; Phenomonex, Torrance, Calif.; eluent: 0 to 100% MeCN+0.1% TFA in water+0.1% TFA, over 20 minutes) to afford the title compound.
