A solution of 3-(2′,3′-dimethyl-biphenyl-2-yl)-propionic acid (207 mg, 0.81 mmoles) and thiophene-2-carboxylic acid N′-isopropyl-hydrazide (150 mg, 0.81 mmoles) in DMF (8 mL) was treated with triethylamine (0.34 mL, 2.44 mmoles), HOBT (132 mg, 0.98 mmoles) and EDCI (156 mg, 0.98 mmoles) at room temperature for 48 h. The reaction mixture was partitioned between 1N HCl and dichloromethane. The organic layer was washed successively with 1N NaOH and brine, then dried over sodium sulfate, filtered and concentrated. The crude was absorbed on silica and purified on a silica gel column with a 20-50% ethyl acetate/hexanes gradient to afford the product (173 mg, 51%). LC-MS m/e 421.46 (M+H+)
