Catalytic Enantioselective 1,3‐Alkyl Shift in Alkyl Aryl Ethers: Efficient Synthesis of Optically Active 3,3′‐Diaryloxindoles

Abstract

Reported is the first organocatalytic asymmetric 1,3-alkyl shift in alkyl aryl ethers for the synthesis of chiral 3,3'-diaryloxindoles using a chiral Brønsted acid catalyst. Preliminary results showed that each enantiomer of the 3,3'-diaryloxindole, and a racemic mixture, showed different antiproliferative activities against HeLa cell lines by using an MTT assay.

Unexpected Biosynthesis of Fluorescein-Like Arthrocolins against Resistant Strains in an Engineered Escherichia coli

“…Multiaryl carbon core containing compounds represent a unique family of complex and dense architectures with importance in medicinal chemistry, materials science, and potential drug candidates. − However, indole as a building block has only been found in naturally occurring compounds with diaryl carbon cores. Interestingly, because indole is a prevalent building block in numerous biologically active compounds possessing multiaryl carbon cores, such as diverse pharmaceuticals including cassigarol B, letrozole, vorozole, paraphenyl-substituted diindolylmethanes, and triphenylmethylamides, methods for incorporation of indole in multiaryl methanes have been intensely explored, and indole as a subunit was also found in chemically synthesized triaryl carbon core containing compounds. − However, until now, no indole bearing tetra-aryl carbon cores, neither natural products nor synthetic products, have been reported. Thus, metabolites 21 – 23 are the first examples embedded with indolyltriphenyl carbon cores.…”

Tandem Insertion–[1,3]‐Rearrangement: Highly Enantioselective Construction of α‐Aminoketones

“…However, catalytic asymmetric versions of [1,3]‐rearrangement of vinyl ethers are extremely rare . In 2018, Patil and co‐workers demonstrated an early example of chiral phosphoric acid catalyzed enantioselective [1,3] O‐to‐C rearrangement of aryl substituted oxindole ethers to generate 3‐phenol substituted oxindole derivatives (Scheme a) . Recently, the group of Ishihara developed a chiral Cu(II) complex promoted asymmetric rearrangement of naphthol‐derived vinyl ethers which yielded 1‐allylnaphthalenone derivatives (Scheme b) .…”

CLPTM1L induces estrogen receptor β signaling-mediated radioresistance in non-small cell lung cancer cells

“…Cell growth assays were carried out using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diph-enyltetrazolium bromide) reagent (Sigma, USA) as described previously [ 52 ]. In brief, transfected cells were trypsinized, counted, and plated into 96-well plates.…”