Cholecystokinin-octapeptide was synthesized by enzymatic condensations of three fragments, without side-chain protection, except for Tyr. Fmoc-Asp-Tyr (SO3Ba1/2)-OH, prepared by the concerted action of proteases, followed by pyridinium trifluoroacetylsulfate treatment, was used as the N-terminal fragment. In the final step, the Nα-Fmoc group employed as a sole protecting group was easily removed by base treatment without affecting the SO3 moiety.
胆囊收缩素八肽通过三段的酶促缩合合成,除了
酪氨酸外,没有侧链保护。Fmoc-Asp-Tyr (SO3Ba1/2)-OH 由
蛋白酶的协同作用制备而成,随后经过
吡啶三
氟乙酰硫酸处理,用作N端片段。在最后一步中,作为唯一保护基团的Nα-Fmoc基团通过碱处理轻松去除,而不影响SO3部分。