To a suspension of (2S)-1-[(4-chlorophenyl)sulfonyl]-2-methylpiperazine hydrochloride (Description 4) (105 mg, 0.338 mmol), EDC (71.2 mg, 0.371 mmol), HOBT.H2O (56.9 mg, 0.371 mmol) and 6-methyl-3-pyridinecarboxylic acid (51.0 mg, 0.372 mmol) in DCM (5 ml) was added N-ethylmorpholine (0.090 ml, 0.710 mmol). The reaction was stirred for 18 h at ambient temperature. To the reaction was added water (3 ml) and the organic layer collected via a hydrophobic frit. The organic layer was reduced in volume to approximately 2 ml then loaded onto a silica SP4 chromatography cartridge. The cartridge was eluted with ethyl acetate then a gradient from 0-10% (20% methanol in dichloromethane) in ethyl. Fractions containing the desired product were combined and reduced in vacuo to yield the title compound as a white solid (55 mg).
