A new and efficient asymmetric synthesis of an A-ring precursor to physiologically active 1.alpha.-hydroxyvitamin D3 steroids
摘要:
A highly stereocontrolled and mild Diels-Alder cycloaddition involving stereochemically matched pyrone (S)-lactate 4 and Lewis acid (-)-Pr(hfc)3 produced bicyclic lactone endo-5 via a double stereodifferentiation process. Bicyclic lactone 5 was then transformed smoothly and in high yield into phosphine oxide (-)-1, an important A-ring precursor to various physiologically active 1alpha-hydroxyvitamin D3 steroids.
Heterocyclic mutilin esters and their use as antibacterials
申请人:——
公开号:US20040058937A1
公开(公告)日:2004-03-25
Pleuromutilin compounds of the formula:
1
are of use in anti-bacterial therapy.
Pleuromutilin化合物的公式为:1在抗菌疗法中有用。
Gram-Scale Enantioselective Synthesis of (+)-Lucidumone
作者:Guanghao Huang、Cyrille Kouklovsky、Aurélien de la Torre
DOI:10.1021/jacs.2c08760
日期:2022.10.5
The first enantioselective total synthesis of (+)-lucidumone is described through a 13-step synthetic pathway (longest linear sequence). The key steps involve the formation of a bridged bicyclic lactone by an enantioselective inverse-electron-demand Diels–Alder cycloaddition, C–O bond formation to assemble two fragments, and a one-pot retro-[4 + 2]/[4 + 2] cycloaddition cascade. The synthesis is scalable
Diastereo‐ and Enantioselective Inverse‐Electron‐Demand Diels–Alder Cycloaddition between 2‐Pyrones and Acyclic Enol Ethers
作者:Guanghao Huang、Régis Guillot、Cyrille Kouklovsky、Boris Maryasin、Aurélien de la Torre
DOI:10.1002/anie.202208185
日期:2022.10.17
The inverse-electron-demand Diels–Alder cycloaddition between 2-pyrones and acyclic enolethers was investigated. Bridged bicyclic lactones were obtained diastereo- and enantioselectively and converted into synthetically relevant polysubstituted enantioenriched cyclohexene and cyclohexadiene derivatives. Mechanistic evidence as well as DFT calculations point towards a stepwise mechanism.
Total Synthesis of Lucidumone: Attempted Shortcuts, Dead Ends and Lessons Learnt
作者:Aurélien de la Torre、Guangho Huang、Amaury Laporte、Lucas Pagès、Cyrille Kouklovsky
DOI:10.1055/s-0042-1751529
日期:2024.5
a meroterpenoid isolated from the mushroom Ganoderma lucidum, displaying selective COX-2 inhibitory activity. In this work, we detail our synthetic efforts which led to the first enantioselective synthesis of lucidumone in 13 steps (longest linear sequence). Beyond the key retro-[4+2]/intramolecular Diels–Alder cascade, we discuss the difficulties regarding fragment assembly, introduction of the methyl
Cycloaddition reactions between the chiral 2-pyrone derivatives 3 and various dienophiles, catalysed by lanthanide shift reagents, afford bicyclic lactones 8 in high diastereomeric excesses.