Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

A Concise Total Synthesis of Dictyodendrins F, H, and I Using Aryl Ynol Ethers as Key Building Blocks.

ABSTRACT: We report a concise total synthesis of dictyodendrin F and the first total syntheses of dictyodendrins H and I in six steps. In these syntheses, aryl ynol ethers were employed as the key building blocks to introduce aryl and heteroaryl rings in the dictyodendrins. This rapid synthesis utilized a novel hetero-[2 + 2]-cycloaddition reaction between two aryl ynol ethers to yield a cyclobutenone ring. The cyclobutenone was sequentially converted into a highly substituted carbazole via a retro-4?/6?-electrocyclization-N-acylation cascade reaction to provide the dictyodendrin core. Consecutive intramolecular oxidative coupling and deprotection gave dictyodendrins F, H, and I.

SUBMITTER: Zhang W

PROVIDER: S-EPMC5006189 | biostudies-literature | 2016 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

A Concise Total Synthesis of Dictyodendrins F, H, and I Using Aryl Ynol Ethers as Key Building Blocks.

Zhang Wenhan W Ready Joseph M JM

Journal of the American Chemical Society 20160811 33

We report a concise total synthesis of dictyodendrin F and the first total syntheses of dictyodendrins H and I in six steps. In these syntheses, aryl ynol ethers were employed as the key building blocks to introduce aryl and heteroaryl rings in the dictyodendrins. This rapid synthesis utilized a novel hetero-[2 + 2]-cycloaddition reaction between two aryl ynol ethers to yield a cyclobutenone ring. The cyclobutenone was sequentially converted into a highly substituted carbazole via a retro-4π/6π- ...[more]

PMID: 27471872

Similar Datasets

Gold(I)-Catalyzed Intermolecular Formal [4+2] Cycloaddition of O-Aryl Ynol Ethers and Enol Ethers: Synthesis of Chromene Derivatives.

Project description:Gold(I)-catalyzed formal [4+2] cycloaddition of O-aryl ynol ethers 1 and enol ethers 2 is described. This intermolecular reaction between two electron-rich unsaturated systems takes place, under mild conditions, in the presence of 5 mol% [IPrAu(CH3 CN)]SbF6 as catalyst giving chromene derivatives with good yields. The cycloaddition is completely regio- and stereoselective, as well as versatile for both reactives. Silyl enol ethers can also react in the same way and under the same reaction conditions with quantitative yields. A plausible mechanism through a selective addition of the enol ether to the alkyne gold activated complex followed by an intramolecular aromatic electrophilic substitution is proposed. Several experimental results support the presence of a cationic oxonium intermediate prior to the aromatic substitution. The reaction represents a new entry to the chromene core.

| S-EPMC8518403 | biostudies-literature

The ketene-surrogate coupling: catalytic conversion of aryl iodides into aryl ketenes through ynol ethers.

Project description:tert-Butoxyacetylene is shown to undergo Sonogashira coupling with aryl iodides to yield aryl-substituted tert-butyl ynol ethers. These intermediates participate in a [1,5]-hydride shift, which results in the extrusion of isobutylene and the generation of aryl ketenes. The ketenes are trapped in situ with multiple nucleophiles or undergo electrocyclic ring closure to yield hydroxynaphthalenes and quinolines.

| S-EPMC4134717 | biostudies-literature

Metal-Free Synthesis of Polysubstituted Triazoloquinoxalines Using Alkynols as the Key Building Blocks.

Project description:o-Phenylenediamines, o-nitroanilines, and Boc-o-phenylenediamines were converted to N-Ts/Ns-o-phenylenediamines, followed by Mitsunobu alkylation with prop-2-yn-1-ols. After one-pot azidation, the resulting intermediates underwent Huisgen cycloaddition, which yielded Ts/Ns-dihydrotriazoloquinoxalines. Cleavage of the arylsulfonyl moiety provided (dihydro)triazoloquinoxalines with the possibility of modifying the N 5 position. The application of but-3-yn-1-ols and pent-4-yn-1-ols allowed the preparation of benzotriazolodiazepines and benzotriazolodiazocines. The developed protocols enable the preparation of diversely substituted products from readily available starting materials under mild and metal-free conditions.

| S-EPMC11411547 | biostudies-literature

New Synthesis of Diarylmethanes, Key Building Blocks for SGLT2 Inhibitors.

Project description:Synthesis of diarylmethanes, a key building block for SGLT2 inhibitors, has been developed through ketone synthesis by Friedel-Crafts acylation with TiCl4, followed by reduction with TiCl4/NaBH4. The new protocol proceeded more cleanly than the previous methods employing AlCl3 and BF3·OEt2/Et3SiH to provide the diarylmethanes corresponding to canagliflozin, empagliflozin, and luseogliflozin in a highly expedient and affordable manner. In the case of a diarylmethane for the synthesis of dapagliflozin, the reduction step took place by an alternative method using InCl3/Al/BF3·OEt2.

| S-EPMC10193421 | biostudies-literature

Ribozyme-catalysed RNA synthesis using triplet building blocks.

Project description:RNA-catalyzed RNA replication is widely believed to have supported a primordial biology. However, RNA catalysis is dependent upon RNA folding, and this yields structures that can block replication of such RNAs. To address this apparent paradox, we have re-examined the building blocks used for RNA replication. We report RNA-catalysed RNA synthesis on structured templates when using trinucleotide triphosphates (triplets) as substrates, catalysed by a general and accurate triplet polymerase ribozyme that emerged from in vitro evolution as a mutualistic RNA heterodimer. The triplets cooperatively invaded and unraveled even highly stable RNA secondary structures, and support non-canonical primer-free and bidirectional modes of RNA synthesis and replication. Triplet substrates thus resolve a central incongruity of RNA replication, and here allow the ribozyme to synthesise its own catalytic subunit '+' and '-' strands in segments and assemble them into a new active ribozyme.

| S-EPMC6003772 | biostudies-literature

Synthesis of push-pull-activated ynol ethers and their evaluation in the bioorthogonal hydroamination reaction.

Project description:A new class of push-pull-activated alkynes featuring di- and trifluorinated ynol ethers was synthesized. The difluorinated ynol ether exhibited an optimal balance of stability and reactivity, displaying a substantially improved half-life in the presence of aqueous thiols over the previously reported 1-haloalkyne analogs while reacting just as fast in the hydroamination reaction with N,N-diethylhydroxylamine. The trifluorinated ynol ether reacted significantly faster, exhibiting a second order rate constant of 0.56 M-1 s-1 in methanol, but it proved too unstable toward thiols. These fluorinated ynol ethers further demonstrate the importance of the hyperconjugation-rehybridization effect in activating alkynes and demonstrate how substituent effects can both activate and stabilize alkynes for bioorthogonal reactivity.

| S-EPMC9769999 | biostudies-literature

Concise synthesis of 3-alkylthieno[3,2-<i>b</i>]thiophenes; building blocks for organic electronic and optoelectronic materials.

Project description:Four step synthesis of 3-alkylthieno[3,2-b]thiophenes in the literature was reduced to two steps in good yields, through the preparation of the mono ketone, i.e. 1-(thiophene-3-ylthio)alkan-2-one, from 3-bromothiophene and ring formation reaction. This convenient method provides an easy access with good yields to the preparation of 3-alkylthieno[3,2-b]thiophenes, which are important materials for organic electronic and optoelectronic applications. SEM, AFM and contact angle (CA) analyses of their electropolymers on indium tin oxide (ITO) indicated that as the alkyl chains became longer, the polymers provide a more hydrophobic layer with CA up to 107°.

| S-EPMC9075834 | biostudies-literature

Concise, enantioselective total synthesis of (-)-alstonerine.

Project description:A novel enantioselective total synthesis of (-)-alstonerine has been completed that requires only 15 steps from L-tryptophan. The synthesis features the first application of a Pauson-Khand reaction to synthesize an azabridged bicyclic skeleton. [reaction: see text]

| S-EPMC2516964 | biostudies-literature

Concise total synthesis of (±)-actinophyllic acid.

Project description:A concise total synthesis of the complex indole alkaloid (±)-actinophyllic acid was accomplished by a sequence of reactions requiring only 10 steps from readily-available, known starting materials. The approach featured a Lewis acid-catalyzed cascade of reactions involving stabilized carbocations that delivered the tetracyclic core of the natural product in a single chemical operation. Optimal conversion of this key intermediate into (±)-actinophyllic acid required judicious selection of a protecting group strategy.

| S-EPMC4034156 | biostudies-literature

A Concise Total Synthesis of (±)-Vibralactone.

Project description:Disclosed is a five-step synthesis of (±)-vibralactone, a biologically active terpenoid natural product. A key photochemical valence isomerization of 3-prenyl-pyran-2-one produces both the all-carbon quaternary stereocenter and the β-lactone at an early stage. Cyclopropanation of the resulting bicyclic β-lactone produces a strained housane structure that is converted to the natural product through a sequential ring expansion and reduction strategy. This concise and modular route to the natural product provides the shortest total synthesis of (±)-vibralactone reported to date.

| S-EPMC6351154 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data