Ha Khanh, Lebedyeva Iryna, Hamedzadeh Sadra, Li Zhiliang, Quiñones Ryan, Pillai Girinath G, Williams Byron, Nasajpour Amir, Martin Kristin, Asiri Abdullah M, Katritzky Alan R
Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, FL 32611-7200 (USA).
Chemistry. 2014 Apr 22;20(17):4874-9. doi: 10.1002/chem.201304262. Epub 2014 Apr 2.
Dimerization-macrocyclization has been a long-standing problem in the cyclization of peptides since, together with the desired cyclic product, many cyclic oligomers and linear polymers may also be formed during the reaction. Therefore, the development of a process that affords the cyclic dimer predominantly is difficult. A novel and versatile strategy for the synthesis of symmetric cyclo-tetrapeptides by palladium-promoted tandem deprotection/cyclo-dimerization from readily available Cbz-dipeptidoyl benzotriazolides is reported (Cbz=carboxybenzyl).
自肽环化反应以来，二聚化-大环化一直是肽环化中存在的一个长期问题，因为在反应过程中，除了所需的环状产物外，还可能形成许多环状低聚物和线性聚合物。因此，开发一种主要生成环状二聚体的方法很困难。本文报道了一种新颖且通用的策略，通过钯促进的串联脱保护/环二聚化反应，从易于获得的Cbz-二肽酰苯并三唑合成对称环四肽（Cbz=羧基苄基）。
