commercial macrolide antibiotic fidaxomicin was synthesized in a highly convergent manner. Salient features of this synthesis include a β-selective noviosylation, a β-selective rhamnosylation, a ring-closing metathesis, a Suzuki coupling, and a vinylogous Mukaiyama aldol reaction. Careful choice of protecting groups and fine-tuning of the glycosylation reactions led to the first total synthesis of fidaxomicin
Total Synthesis and Structural Revision of Mangrolide D
作者:Hiromu Hattori、Lukas V. Hoff、Karl Gademann
DOI:10.1021/acs.orglett.9b01256
日期:2019.5.3
steps feature an Au-catalyzed glycosylation, aza-Michael addition, and LaLi3tris(binaphthoxide) catalyzed epoxidation. Detailed analysis of the constitution and configuration of the carbohydrate segment and the total synthesis of the revised structure led to structural revision of the originally proposed structure.
synthetically challenging seven/eight-membered fused carbocycles through rhodium-catalyzed coupling between 4σ-donor (benzocyclobutenones) and pendant diene (4π) motifs in good yields (up to 90 %). A mechanism was proposed based on kinetic and 13C-labeling experiments. Notably, one product was found to be a potent and selective liver X receptor β binding ligand (KD=0.64 μM).
开发了 I 型 [4σ+4π] 和 [4σ+4π−1] 环加成,通过 4σ-供体(苯并环丁烯酮)和侧链二烯 (4π) 基序之间的铑催化偶联,获得具有合成挑战性的七/八元稠合碳环。产率(高达 90%)。基于动力学和13 C 标记实验提出了一种机制。值得注意的是,一种产品被发现是一种有效的、选择性的肝脏 X 受体 β 结合配体 (KD=0.64 μM)。
Stereodivergent Construction of 1,5/1,7‐Nonadjacent Tetrasubstituted Stereocenters Enabled by Pd/Cu‐Cocatalyzed Asymmetric Heck Cascade Reaction
作者:Panpan Li、Zijiao Liu、Xiaohong Huo、Wanbin Zhang
DOI:10.1002/anie.202407498
日期:2024.8.26
A stereodivergent construction of 1,5/1,7-nonadjacent tetrasubstituted stereocenters enabled by a Pd/Cu-cocatalyzed asymmetric Heck cascadereaction has been developed. An array of highly functionalized chiral molecules bearing two privileged scaffolds, oxindoles and α-amino acids, were smoothly prepared. Notably, all four stereoisomers of the desired products were obtained through orthogonal permutations