peptide synthesis (SPPS). The robustness of the allenone-mediated peptide bond formation was showcased incisively by the synthesis of carfilzomib, which involved a rare racemization-/epimerization-free N to C peptide elongation strategy. Furthermore, the successful synthesis of the model difficult peptide ACP (65–74) on a solid support suggested that this method was compatible with SPPS. This method combines
Allenone 首次被鉴定为一种高效的肽偶联剂。肽键以α-羰基乙烯基酯为关键中间体形成,其形成和随后的氨解以无外消旋/差向异构化的方式自发进行。丙二烯酮偶联试剂不仅对简单酰胺和二肽的合成有效,而且还适用于肽片段缩合和固相肽合成 (SPPS)。卡非佐米的合成充分展示了丙二烯酮介导的肽键形成的稳健性,该合成涉及一种罕见的无消旋化/差向异构化的 N 到 C 肽延伸策略。此外,在固体支持物上成功合成模型困难肽 ACP (65-74) 表明该方法与 SPPS 兼容。该方法结合了传统活性酯和偶联剂的优点,同时克服了两种策略的缺点。因此,这种丙二烯酮介导的肽键形成策略代表了肽合成的颠覆性创新。
the operationally simple dehydrative condensation of carboxylic acids. This reagent comprises an ATD core and DMAP as the leaving group, which is liberated into the reaction system to accelerate acyltransfer reactions. Upon adding ATD-DMAP to a mixture of carboxylic acids and alcohols in the presence of an amine base, the corresponding esters were formed rapidly at room temperature. Moreover, dehydrative
开发了一种新的基于三嗪二酮的试剂 ( N , N'-二烷基)三嗪二酮-4-(二甲氨基)吡啶 (ATD-DMAP),用于操作简单的羧酸脱水缩合。该试剂包含一个ATD核和作为离去基团的DMAP,它被释放到反应体系中以加速酰基转移反应。在胺碱存在下将 ATD-DMAP 添加到羧酸和醇的混合物中,在室温下迅速形成相应的酯。此外,使用 ATD-DMAP 使羧酸和胺之间的脱水缩合以高产率进行。
Highly Efficient and Stereoselective Thioallylation of Alkynes: Possible Gold Redox Catalysis with No Need for a Strong Oxidant
作者:Jin Wang、Shuyao Zhang、Chang Xu、Lukasz Wojtas、Novruz G. Akhmedov、Hao Chen、Xiaodong Shi
DOI:10.1002/anie.201802540
日期:2018.6.4
Stereoselectivethioallylation of alkynes under possiblegoldredoxcatalysis was accomplished with high efficiency (as low as 0.1 % catalyst loading, up to 99 % yield) and broad substrate scope (various alkynes, inter‐ and intramolecular fashion). The gold(I) catalyst acts as both a π‐acid for alkyne activation and a redox catalyst for AuI/III coupling, whereas the sulfonium cation generated in situ
在可能的金氧化还原催化下,炔烃的立体选择性硫代烯丙基化反应效率高(催化剂负载量低至0.1%,产率高达99%),底物范围广(各种炔烃,分子间和分子内方式)。金(I)催化剂既充当炔烃活化的π-酸,又充当Au I / III偶联的氧化还原催化剂,而原位生成的sulf阳离子则起弱氧化剂的作用。这种新颖的方法为金的氧化还原催化提供了令人兴奋的系统,而无需强氧化剂。
Ynamides as Racemization-Free Coupling Reagents for Amide and Peptide Synthesis
A highly efficient, two-step, one-pot synthetic strategy for amides and peptides was developed by employing ynamides as novel couplingreagents under extremely mild reaction conditions. The ynamides not only are effective for simple amide and dipeptide synthesis but can also be used for peptide segment condensation. Importantly, no racemization was detected during the activation of chiral carboxylic