“…Following the similar procedure for 3a, the crude product, which was prepared from the carboxylic acid 17 (200 mg, 1.1 mmol), the propargylic alcohol 18b [19] (181 mg, 1.6 mmol), DMAP (39 mg, 0.32 mmol), and DCC (326 mg, 1.6 mmol) in CH 2 Cl 2 (5 mL) at room temperature for 20 min, was purified by column chromatography on silica gel (hexane/AcOEt = 3/1) to give 3b as an off-white solid (19) Following the similar procedure for 3a, the crude product, which was prepared from 17 (82 mg, 0.42 mmol), the propargylic alcohol 18c [20] …”