Synthesis of bis[N,N-diallyl-[d-Ala2, l-Leu5]-enkephalyl]cystine, which is expected to be a selective opioid δ-receptor antagonist, was studied. The mercapto group of cysteine was protected by the dimethylphosphinothioyl(Mpt) group. For the removal of this group without damaging the allyl moiety, new mild removal conditions by use of KF/18-crown-6 in a solvent mixture of acetonitrile–methanol are proposed. Bis[d-Ala2, l-Leu5]-enkephalyl]cystine was also prepared in a similar manner.
对双[N,N-二烯丙基-[d-Ala2, l-Leu5]-脑啡基]胱
氨酸(有望成为选择性阿片δ受体拮抗剂)的合成进行了研究。半胱
氨酸的巯基由
二甲基硫代膦酰(Mpt)基团保护。为了在不破坏烯丙基部分的情况下去除该基团,提出了在
乙腈-
甲醇溶剂混合物中使用KF/
18-冠-6的新型温和去除条件。双[d-Ala2, l-Leu5]-脑啡基]胱
氨酸也以类似的方式制备。