Open chain Cbz‐L‐aa1‐L‐Pro‐Bt (Bt=benzotriazole) sequences were converted into either the corresponding trans‐ or cis‐fused 2,5‐diketopiperazines (DKPs) depending on the reaction conditions. Thermodynamic tandem cyclization/epimerization afforded selectively the corresponding trans‐DKPs (69–75 %). Complementarily, tandem deprotection/cyclization led to the cis‐DKPs (65–72 %). A representative set of
开链C
BZ-大号-
AA 1 -大号-Pro-Bt
基因(Bt
基因=苯并三唑)序列转化成任一相应的反式-或顺式-融合根据反应条件2,5-二酮
哌嗪(DKPs)。热力学串联环化/表位选择性地提供了相应的反式-DKP(69-75%)。互补地,串联脱保护/环化导致顺式-DKP(65-72%)。已制备了一组代表性的脯
氨酸含顺式和反式DKP。基于手性HPLC,动力学和计算研究的机械研究使结果合理化。