Synthesis of quinone/hydroquinone sesquiterpenes

Marcos, Isidro S.; Conde, A.; Moro, Rosalina F.; Basabe, P.; Dı́ez, David; Urones, Julio G.

doi:10.1016/j.tet.2010.08.038

Cited by 42 publications

(43 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previously, these interesting scaffolds have been functionalized using radicals generated with metal-based catalysts to afford mostly arylated quinones from organoboron compounds 30 and carboxylic acids, 31 among others. 32 However, aldehydes have never been employed before as alkyl radical precursors with this class of substrates, 33 thus ignoring an important feedstock that could help increase the chemical space.…”

Section: Resultsmentioning

confidence: 99%

Late-Stage C–H Alkylation of Heterocycles and 1,4-Quinones via Oxidative Homolysis of 1,4-Dihydropyridines

et al. 2017

View full text Add to dashboard Cite

Under oxidative conditions, 1,4-dihydropyridines (DHPs) undergo a homolytic cleavage, forming exclusively a Csp3-centered radical that can engage in the C-H alkylation of heterocyclic bases and 1,4-quinones. DHPs are readily prepared from aldehydes, and, considering that aldehydes normally require harsh reaction conditions to take part in such transformations, with mixtures of alkylated and acylated products often being obtained, this net decarbonylative alkylation approach becomes particularly useful. The present method takes place under mild reaction conditions and requires only persulfate as a stoichiometric oxidant, making the procedure suitable for the late-stage C-H alkylation of complex molecules. Notably, structurally complex pharmaceutical agents could be functionalized or prepared with this protocol, such as the anti-malarial Atovaquone and anti-theilerial Parvaquone, thus evidencing its applicability. Mechanistic studies revealed a likely radical chain process via the formation of a dearomatized intermediate and provided a deeper understanding of the factors governing the reactivity of these radical forebears.

show abstract

Section: Resultsmentioning

confidence: 99%

Late-Stage C–H Alkylation of Heterocycles and 1,4-Quinones via Oxidative Homolysis of 1,4-Dihydropyridines

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The Barton decarboxylation in presence of benzoquinone is the key reaction in this synthesis (Scheme 19) [244]. …”

Section: Radical Decarboxylation and Quinone Addition Reactionmentioning

confidence: 99%

Synthetic Strategies to Terpene Quinones/Hydroquinones

Gordaliza

2012

Marine Drugs

View full text Add to dashboard Cite

The cytotoxic and antiproliferative properties of many natural sesquiterpene-quinones and -hydroquinones from sponges offer promising opportunities for the development of new drugs. A review dealing with different strategies for obtaining bioactive terpenyl quinones/hydroquinones is presented. The different synthetic approches for the preparation of the most relevant quinones/hydroquinones are described.

show abstract

“…By simple variation of the reaction conditions, either the kinetically favoured cis ‐decalin framework (BF 3 ⋅OEt 2 , dichloromethane, T < −10 °C) or the thermodynamically more stable trans ‐decalin system ( p TsOH, benzene, 80 °C) were selectively obtained. While the groups of Marcos and George developed chiral pool strategies to synthesize 11 , the synthesis of arenarol ( 10 ) described by the group of Katoh, uses a Wieland–Miescher ketone derivative –…”

Section: Introductionmentioning

confidence: 99%

Evolution of a Polyene Cyclization Cascade for the Total Synthesis of (−)‐Cyclosmenospongine

Speck

Magauer

2016

Chemistry A European J

View full text Add to dashboard Cite

We report a full account on the development of a unique cationic polyene cyclization for the total synthesis of the tetracyclic meroterpenoid (−)‐cyclosmenospongine. A highly convergent three‐component coupling strategy enabled rapid access to individual cyclization precursors that were tested for their reactivity. The successful transformation generates three rings and sets four consecutive stereocenters in a single operation proceeding in a highly efficient manner to give exclusively the trans‐decalin framework. In addition, we found that the enol ether geometry and the relative configuration of C3 and C8 are crucial for the success of the polyene cyclization.

show abstract

Synthesis of quinone/hydroquinone sesquiterpenes

Cited by 42 publications

References 40 publications

Late-Stage C–H Alkylation of Heterocycles and 1,4-Quinones via Oxidative Homolysis of 1,4-Dihydropyridines

Late-Stage C–H Alkylation of Heterocycles and 1,4-Quinones via Oxidative Homolysis of 1,4-Dihydropyridines

Synthetic Strategies to Terpene Quinones/Hydroquinones

Evolution of a Polyene Cyclization Cascade for the Total Synthesis of (−)‐Cyclosmenospongine

Contact Info

Product

Resources

About