Synthesis of A-ring quinolones, nine-membered oxolactams and spiroindoles by oxidative transformations of 2,3-indolotriterpenoids.

Clicks: 314
ID: 238217
2019
Article Quality & Performance Metrics
Overall Quality
Not rated
Combines reader engagement with the AI quality analysis. This article has not been analysed, so there is no overall score — reader engagement is measured and shown alongside.
AI Quality Assessment
Not analyzed
Readership in this journal
Emerging

Ranked #15 of 57 articles by views in Organic & biomolecular chemistry

Most read Least read

Bar heights use a square-root scale.

Mint this article as an NFT
Not yet minted

Create a permanent, verifiable on-chain record of this article on the Scimatic Network. The NFT is held in your Journament account, and you can withdraw it to your own wallet at any time.

5 SUSD one-off · no wallet required
Sign in to mint
Abstract
This paper describes an access to new nitrogen-containing heterocyclic triterpenoids by the reaction of 2,3-indolotriterpenoids with ozone and dimethyldioxirane. The oxidation of indolo-fused 28-oxo-allobetulin or methyl platanoate with ozone led to a mixture of a quinolone as the major product and a nine-membered 2,3-seco-2-oxolactam and three different types of spiroindoles as byproducts. The formation of quinolone and 2,3-seco-2-oxolactam derivatives could be explained by the standard 1,3-dipolar cycloaddition of ozone to the C2(3)-double bond of the triterpene core similar to the products observed in the ozonolysis of indoles in the Witkop-Winterfeldt oxidation (WWO). The formation of spiroindoles was unexpected and could be explained through the 1,2-cycloaddition of ozone to the C2(3)-double bond with consecutive intramolecular rearrangements of the 2,3-epoxy-intermediate. These spiroindoles seem to be novel structures observed in the WWO reaction. The formation of only two isomeric triterpene spiroindolinones was achieved by the oxidation of 2,3-indolo-28-oxo-allobetulin with dimethyldioxirane that could be explained by the rearrangement of the 2,3-epoxy-intermediate. 19β,28-Epoxy-18α-olean-28-oxo-2-nor-2,3-4'(1H)-quinolone was the most active against HPV-11 with EC50 0.45 μM and SI50 322 in a primary assay and SI90 < 10 against HPV-16 in a secondary assay. The oxidative transformations of indolotriterpenoids have great potential for further modifications towards the preparation of new biologically active compounds.
Reference Key
khusnutdinova2019synthesisorganic Use this key to autocite in the manuscript while using SciMatic Manuscript Manager or Thesis Manager
Authors Khusnutdinova, Elmira F;Kazakova, Oxana B;Lobov, Alexander N;Kukovinets, Olga S;Suponitsky, Kyrill Yu;Meyers, Craig B;Prichard, Mark N;
Journal Organic & biomolecular chemistry
Year 2019
DOI
10.1039/c8ob02624f
URL
Keywords
oxidation sulfone sulfoxide conjugated polymers organic electronics f8bt pcdtbt post-polymerization modification

Citations

No citations found. To add a citation, contact the admin at info@scimatic.org

Comments

No comments yet. Be the first to comment on this article.