1452823-70-9Relevant academic research and scientific papers
TiCl3-Mediated Synthesis of 2,3,3-Trisubstituted Indolenines: Total Synthesis of (+)-1,2-Dehydroaspidospermidine, (+)-Condyfoline, and (?)-Tubifoline
Delayre, Bastien,Piemontesi, Cyril,Wang, Qian,Zhu, Jieping
, p. 13990 - 13997 (2020)
2,3,3-Trisubstituted indolenine constitutes an integral part of many biologically important monoterpene indole alkaloids. We report herein an unprecedented access to this skeleton by a TiCl3-mediated reductive cyclization of tetrasubstituted alkenes bearing a 2-nitrophenyl substituent. The proof of concept is demonstrated firstly by accomplishing a concise total synthesis of (+)-1,2-dehydroaspidospermidine featuring a late-stage application of this key transformation. A sequence of reduction of nitroarene to nitrosoarene followed by 6π-electron-5-atom electrocyclization and a 1,2-alkyl shift of the resulting nitrone intermediate was proposed to account for the reaction outcome. A subsequent total synthesis of (+)-condyfoline not only illustrates the generality of the reaction, but also provides a mechanistic insight into the nature of the 1,2-alkyl shift. The exclusive formation of (+)-condyfoline indicates that the 1,2-alkyl migration follows a concerted Wagner–Meerwein pathway, rather than a stepwise retro-Mannich/Mannich reaction sequence. Conditions for almost quantitative conversion of (+)-condyfoline to (?)-tubifoline by way of a retro-Mannich/1,3-prototropy/transannular cyclization cascade are also documented.
SUBSTITUTED IMIDAZOLECARBOXAMIDE AS BRUTON'S TYROSINE KINASE INHIBITORS
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Page/Page column 60-62, (2021/06/11)
The disclosure relates to a series of substituted imidazolecarboxamide compounds of formula I as BTK (Bruton's Tyrosine Kinase) inhibitors, and the methods of using the same for the treatment of autoimmune disease, inflammatory disease, cancer and potenti
Unified strategy to monoterpene indole alkaloids: Total syntheses of (±)-Goniomitine, (±)-1,2-Dehydroaspidospermidine, (±)-Aspidospermidine, (±)-Vincadifformine, and (±)-Kopsihainanine A
Wagnires, Olivier,Xu, Zhengren,Wang, Qian,Zhu, Jieping
supporting information, p. 15102 - 15108 (2014/12/11)
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 access to cyclopentene intermediates containing all of the carbons present in the natural products and (2) an integrated oxidation/reduction/cyclization (iORC) sequence for skeletal reorganization that converts the cyclopentenes to the pentacyclic structures of the natural products. By incorporation of a geometric constraint to iORC substrates, both the chemoselectivity (C7 vs N1 cyclization) and the stereoselectivity (trans- vs cis-fused ring system) of the cyclization process can be controlled.
Palladium-catalyzed decarboxylative vinylation of potassium nitrophenyl acetate: Application to the total synthesis of (±)-goniomitine
Xu, Zhengren,Wang, Qian,Zhu, Jieping
supporting information, p. 3272 - 3276 (2013/04/10)
Merge and divert: The natural product (±)-goniomitine was synthesized by a method featuring two key steps: 1) fragment coupling to a functionalized cyclopentene by a novel palladium-catalyzed decarboxylative vinylation reaction and 2) an unprecedented one-pot integrated oxidation/reduction/cyclization (IORC) process to convert the substituted cyclopentene into the tetracyclic skeleton of goniomitine with high chemo-, regio-, and diastereoselectivity.
