Publications de Zhengren Xu | EPFL Graph Search

Metamorphosis of cycloalkenes for the divergent total synthesis of polycyclic indole alkaloids

From tryptamine and secologanine, nature generates monoterpene indole alkaloids with an unprecedented level of skeletal diversity through a ‘couple–divert’ sequence. Intrigued by this biosynthetic machinery, new strategies and tactics to access skeletally ...

Royal Society of Chemistry2018

Enantioselective Total Syntheses of (−)-Rhazinilam, (−)-Leucomidine B, and (+)-Leuconodine F

Qian Wang, Jieping Zhu, Zhengren Xu, Dylan Jean Robert Dagoneau

A divergent total synthesis of three structurally distinct natural products from imine 9 was accomplished through an approach featuring: 1) a Pd-catalyzed decarboxylative cross-coupling, and 2) heteroannulation of 9 with bromoacetaldehyde and oxalyl chlori ...

Wiley-Blackwell2016

Total Syntheses of (−)-Mersicarpine, (−)-Scholarisine G, (+)-Melodinine E, (−)-Leuconoxine, (−)-Leuconolam, (−)-Leuconodine A, (+)-Leuconodine F, and (−)-Leuconodine C: Self-Induced Diastereomeric Anisochronism (SIDA) Phenomenon for Scholarisine G and Leuconodines A and C

Qian Wang, Jieping Zhu, Zhengren Xu

Enantioselective total syntheses of title natural products from a common cyclohexenone derivative (S)-18 were reported. Ozonolysis of (S)-18 afforded a stable diketo ester (R)-17 that was subsequently converted to two skeletally different natural products, ...

Amer Chemical Soc2015

An Enantioselective Total Synthesis of (−)-Isoschizogamine

Qian Wang, Jieping Zhu, Xu Bao, Zhengren Xu

A concise enantioselective total synthesis of (¢)- isoschizogamine, a complex bridged polycyclic monoterpene indole alkaloid, was accomplished. N-Alkylation of an enantio- enriched imine with an alkyl iodide afforded an iminium salt, which, upon heating by ...

Wiley-Blackwell2015

Aqueous Titanium Trichloride Promoted Reductive Cyclization of o-Nitrostyrenes to Indoles: Development and Application to the Synthesis of Rizatriptan and Aspidospermidine

Qian Wang, Jieping Zhu, Shuo Tong, Zhengren Xu, Mathias Mamboury

Treatment of o-nitrostyrenes with aqueous TiCl3 solution at room temperature afforded indoles via a formal reductive C(sp2)-H amination process. A range of functions such as halides (Cl, Br), carbonyl (ester, carbamate), cyano, hydroxyl and amino groups we ...

Wiley-Blackwell2015

Unified Strategy to Monoterpene Indole Alkaloids: Total Syntheses of (±)-Goniomitine, (±)-1,2-Dehydroaspidospermidine, (±)-Aspidospermidine, (±)-Vincadifformine, and (±)-Kopsihainanine A

Qian Wang, Jieping Zhu, Zhengren Xu, Olivier Wagnières

Total syntheses of (±)-goniomitine, (±)-1,2-dehydroaspidospermidine, (±)-aspidospermidine, (±)-vincadifformine, and (±)-kopsihainanine A were achieved featuring two common key steps: (1) a palladium-catalyzed decarboxylative vinylation that provides quick ...

Amer Chemical Soc2014

Enantioselective Total Syntheses of Leuconolam–Leuconoxine–Mersicarpine Group Monoterpene Indole Alkaloids

Qian Wang, Jieping Zhu, Zhengren Xu

A unified strategy allowing enantioselective total syntheses of (−)-mersicarpine, (−)-scholarisine G, (+)-melodinine E, (−)-leuconoxine, and (−)-leuconolam from a common cyclohexenone derivative was reported. The Suzuki−Miyaura reaction was used to couple ...

2013

Palladium-Catalyzed Decarboxylative Vinylation of Potassium Nitrophenyl Acetate: Application to the Total Synthesis of (±)-Goniomitine

Qian Wang, Jieping Zhu, Zhengren Xu

Merge and divert. (±)-goniomitine was synthesized featuring two key steps: a) fragment coupling to functionalized cyclopentene by a novel palladium-catalyzed decarboxylative vinylation reaction and b) an unprecedented one-pot integrated oxidation/reduction ...

Wiley-Blackwell2013