Rhodium-Catalyzed Formal C–O Insertion in Carbene/Alkyne Metathesis Reactions: Synthesis of 3-Substituted 3<i>H</i>-Indol-3-ols
作者:Shikun Jia、Guizhi Dong、Chaoqun Ao、Xianxing Jiang、Wenhao Hu
DOI:10.1021/acs.orglett.9b01492
日期:2019.6.7
An efficient and novel rhodium-catalyzed formal C–O insertion reaction of alkyne-tethered diazo compounds for the synthesis of 3H-indol-3-ols is described. A type of donor/donor rhodium carbene generated in situ via a carbene/alkyne metathesis (CAM) process is the key intermediate and terminates in a unique transformation different from donor/acceptor carbenoids. In addition, 18O-labeling experiments
Superacid-catalyzed tandem Meyer–Schuster rearrangement/intramolecular hydroamination of <i>o</i>-anilinopropargyl alcohols for the synthesis of 2,3-dihydro-4(1H)-quinolones
A TfOH-catalyzed synthesis of 2,3-dihydro-4(1H)-quinolones from o-anilinopropargyl alcohols was developed. Studies of N-protecting groups and substituents in phenyl rings showed that diverse groups could be applied. By controlling the catalyst loading, o-anilinopropargyl alcohols underwent the expected transformation smoothly to produce N-protected or N-deprotected 2,3-dihydro-4 (1H)-quinolones in good
This study introduces a novel approach for synthesizing Benzoxazine‐centered Polychiral Polyheterocycles (BPCPHCs) via an innovative asymmetric carbene‐alkyne metathesis‐triggered cascade. Overcoming challenges associated with intricate stereochemistry and multiple chiral centers, the catalytic asymmetric Carbene Alkyne Metathesis‐mediated Cascade (CAMC) is employed using dirhodium catalyst/Brønsted acid co‐catalysis, ensuring precise stereo control as validated by X‐ray crystallography. Systematic substrate scope evaluation establishes exceptional diastereo‐ and enantioselectivities, creating a unique library of BPCPHCs. Pharmacological exploration identifies twelve BPCPHCs as potent Nav ion channel blockers, notably compound 8 g. In vivo studies demonstrate that intrathecal injection of 8 g effectively reverses mechanical hyperalgesia associated with chemotherapy‐induced peripheral neuropathy (CIPN), suggesting a promising therapeutic avenue. Electrophysiological investigations unveil the inhibitory effects of 8 g on Nav1.7 currents. Molecular docking, dynamics simulations and surface plasmon resonance (SPR) assay provide insights into the stable complex formation and favorable binding free energy of 8 g with C5aR1. This research represents a significant advancement in asymmetric CAMC for BPCPHCs and unveils BPCPHC 8 g as a promising, uniquely acting pain blocker, establishing a C5aR1‐Nav1.7 connection in the context of CIPN.