(3S,6S)-3,6-diisobutyl-4-(4-phenoxybenzoyl)piperazin-2-one 、
(3S,6R)-3-isobutyl-6-((methylthio)methyl)piperazin-2-one 、
5-(4-氟苯基)-1,2,4-噁二唑-3-羧酸 以to give the product 296 (58.2 mg, 30% yield) as colorless oil的产率得到(3S,6R)-4-(5-(4-fluorophenyl)-1,2,4-oxadiazole-3-carbonyl)-3-isobutyl-6-((methylthio)methyl)piperazin-2-one