(3S,6S)-4-(5-(3,4-difluorophenyl)isoxazole-3-carbonyl)-3,6-diisobutylpiperazin-2-one 、
(3S,6S)-3,6-diisobutylpiperazin-2-one 、
5-(2-氟苯基)-1,2-恶唑-3-羧酸 以to give the product 142 (52.6 mg, 27.9% yield) as a white solid的产率得到(3S,6S)-4-(5-(2-fluorophenyl)isoxazole-3-carbonyl)-3,6-diisobutylpiperazin-2-one