Side-Chain-Functionalized Dipeptides Derived from 6,5-Fused Bicyclic Thiazolidinlactams
作者:Peter Tremmel、Jörg Brand、Volker Knapp、Armin Geyer
DOI:10.1002/ejoc.200390133
日期:2003.3
mimetics 6 and 7. Compound 3 forms the single acetonide 9, which permits the regioselective alkylation of the γ-hydroxy group of the bicyclic framework. Subsequent deprotection and exchange of the α-hydroxy functionality against a Boc-protected amino group (13) demonstrates the regioselective side-chain modification of bicyclic dipeptides. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany,
D-阿拉伯糖醛酸内酯 (2) 与 L-半胱氨酸甲酯的缩合产生双环噻唑烷内酰胺 3 作为单一非对映异构体,在 (S) 构型中具有新的桥头立体中心。α-羟基的区域选择性活化产生三氟甲磺酸酯 4,而不需要残留羟基上的保护基团。随后的叠氮化物交换、还原和 Boc 保护,产生差向异构二肽模拟物 6 和 7。化合物 3 形成单个丙酮化物 9,这允许双环骨架的 γ-羟基的区域选择性烷基化。随后针对 Boc 保护的氨基 (13) 对 α-羟基官能团进行脱保护和交换,证明了双环二肽的区域选择性侧链修饰。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)