Browse
Submit Data
Databases
API
Help

Dataset Information

19 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Stereochemical control of the Passerini reaction.

ABSTRACT: A catalytic asymmetric Passerini reaction using tridentate indan (pybox) Cu(II) Lewis acid complex 4 with substrates capable of bidentate coordination has been achieved. The reaction occurs via ligand-accelerated catalysis.

SUBMITTER: Andreana PR

PROVIDER: S-EPMC4134661 | biostudies-literature | 2004 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Stereochemical control of the Passerini reaction.

Andreana Peter R PR Liu Chang C CC Schreiber Stuart L SL

Organic letters 20041101 23

A catalytic asymmetric Passerini reaction using tridentate indan (pybox) Cu(II) Lewis acid complex 4 with substrates capable of bidentate coordination has been achieved. The reaction occurs via ligand-accelerated catalysis. ...[more]

PMID: 15524450

Similar Datasets

An Efficient Passerini Tetrazole Reaction (PT-3CR).

Project description:A sonication accelerated, catalyst free, simple, high yielding and efficient method for the Passerini-type three component reaction (PT-3CR) has been developed. It comprises reaction of an aldehyde/ketone, a isocyanide and a TMS-azide in methanol:water (1:1) as the solvent system. Use of sonication not only accelerated the rate of the reaction but also provided up to quantitative yields. This reaction is applicable to a broad scope of aldehyde/ketone and isocyanides.

| S-EPMC5102161 | biostudies-literature

C-Linked Glycomimetic Libraries Accessed by the Passerini Reaction.

Project description:Carbohydrates and their conjugates are the most abundant natural products, with diverse and highly important biological roles. Synthetic glycoconjugates are versatile tools used to probe biological systems and interfere with them. In an endeavor to provide an efficient route to glycomimetics comprising structurally diverse carbohydrate units, we describe herein a robust, stereoselective, multicomponent approach. Isopropylidene-protected carbohydrate-derived aldehydes and ketones were utilized in the Passerini reaction, giving different glycosylated structures in high yields and diastereoselectivities up to 90:10 diastereomeric ratio (d.r). Access to highly valuable building blocks based on α-hydroxy C-glycosyl acids or more complex systems was elaborated by simple post-condensation methodologies.

| S-EPMC6940731 | biostudies-literature

Passerini-type reaction of boronic acids enables α-hydroxyketones synthesis.

Project description:Multicomponent reactions (MCRs) facilitate the rapid and diverse construction of molecular scaffolds with modularity and step economy. In this work, engagement of boronic acids as carbon nucleophiles culminates in a Passerini-type three-component coupling reaction towards the synthesis of an expanded inventory of α-hydroxyketones with skeletal diversity. In addition to the appealing features of MCRs, this protocol portrays good functional group tolerance, broad substrate scope under mild conditions and operational simplicity. The utility of this chemistry is further demonstrated by amenable modifications of bioactive products and pharmaceuticals as well as in the functionalization of products to useful compounds.

| S-EPMC7815879 | biostudies-literature

Synthesis of Stimuli-Responsive Heterofunctional Dendrimer by Passerini Multicomponent Reaction.

Project description:We report the synthesis of a structurally diverse amphiphilic dendrimer with oxidation and ultraviolet light-sensitive groups incorporated in the dendrimer interior. Convergent synthesis is utilized by reacting branched repeating units with a nonbranched functional molecule by two synthetic strategies, Passerini multicomponent reaction and azide-alkyne cycloaddition reaction. The periphery of dendrimer was functionalized by methoxy poly(ethylene glycol) to obtain a dendrimer with a hydrophobic core and hydrophilic peripheral chains. The G2-PEG dendrimer characterized by NMR, GPC, and MALDI-TOF MS for structural integrity and oxidation- and photo-triggered degradations of the G2-PEG dendrimer was investigated. The self-assembled morphology of the dendrimer in the presence of organic dye was also investigated by TEM and DLS analyses, together with dissipative particle dynamics simulation. The encapsulation of dye molecules in self-assembled nanospheres of the dendrimer and their responsive releases, triggered by the efficient disassembly of a dendrimer, have been demonstrated.

| S-EPMC6648294 | biostudies-literature

Artificial Macrocycles by Ugi Reaction and Passerini Ring Closure.

Project description:Artificial macrocycles can be convergently synthesized by a sequence of an Ugi multicomponent reaction (MCR) followed by an intramolecular Passerini MCR used to close the macrocycle. Significantly, in this work, the first intramolecular macrocyclization through a Passerini reaction is described. We describe 21 macrocycles of a size of 15-20. The resulting macrocyclic depsipeptides are model compounds for natural products and could find applications in drug discovery.

| S-EPMC6280654 | biostudies-other

Stereochemical control of skeletal diversity.

Project description:[reaction: see text]. Substrates having appendages that pre-encode skeletal information (sigma-elements) can be converted into products having distinct skeletons using a common set of reaction conditions. The sequential use of the Ugi 4CC-IMDA reaction, followed by allylation, hydrolysis, and acylation of a chiral amino alcohol appendage (sigma-element), leads to substrates for a ROM/RCM or RCM reaction. The stereochemistry of the sigma-element and not its constitution controls the outcome of the pathway selected. This work illustrates the potential of linking stereochemical control to the challenging problem of skeletal diversity.

| S-EPMC4134662 | biostudies-literature

Stereochemical Control Yields Mucin Mimetic Polymers.

Project description:All animals except sponges produce mucus. Across the animal kingdom, this hydrogel mediates surface wetting, viscosity, and protection against microbes. The primary components of mucus hydrogels are mucins-high molecular weight O-glycoproteins that adopt extended linear structures. Glycosylation is integral to mucin function, but other characteristics that give rise to their advantageous biological activities are unknown. We postulated that the extended conformation of mucins is critical for their ability to block microbial virulence phenotypes. To test this hypothesis, we developed synthetic mucin mimics that recapitulate the dense display of glycans and morphology of mucin. We varied the catalyst in a ring-opening metathesis polymerization (ROMP) to generate substituted norbornene-derived glycopolymers containing either cis- or trans-alkenes. Conformational analysis of the polymers based on allylic strain suggested that cis- rather than trans-poly(norbornene) glycopolymers would adopt linear structures that mimic mucins. High-resolution atomic force micrographs of our polymers and natively purified Muc2, Muc5AC, and Muc5B mucins revealed that cis-polymers adopt extended, mucin-like structures. The cis-polymers retained this structure in solution and were more water-soluble than their trans-analogs. Consistent with mucin's linear morphology, cis-glycopolymers were more potent binders of a bacterial virulence factor, cholera toxin. Our findings highlight the importance of the polymer backbone in mucin surrogate design and underscore the significance of the extended mucin backbone for inhibiting virulence.

| S-EPMC8155468 | biostudies-literature

Asymmetric Reduction of Activated Alkenes by Pentaerythritol Tetranitrate Reductase: Specificity and Control of Stereochemical Outcome by Reaction Optimisation.

Project description:We show that pentaerythritol tetranitrate reductase (PETNR), a member of the 'ene' reductase old yellow enzyme family, catalyses the asymmetric reduction of a variety of industrially relevant activated alpha,beta-unsaturated alkenes including enones, enals, maleimides and nitroalkenes. We have rationalised the broad substrate specificity and stereochemical outcome of these reductions by reference to molecular models of enzyme-substrate complexes based on the crystal complex of the PETNR with 2-cyclohexenone 4a. The optical purity of products is variable (49-99% ee), depending on the substrate type and nature of substituents. Generally, high enantioselectivity was observed for reaction products with stereogenic centres at Cbeta (>99% ee). However, for the substrates existing in two isomeric forms (e.g., citral 11a or nitroalkenes 18-19a), an enantiodivergent course of the reduction of E/Z-forms may lead to lower enantiopurities of the products. We also demonstrate that the poor optical purity obtained for products with stereogenic centres at Calpha is due to non-enzymatic racemisation. In reactions with ketoisophorone 3a we show that product racemisation is prevented through reaction optimisation, specifically by shortening reaction time and through control of solution pH. We suggest this as a general strategy for improved recovery of optically pure products with other biocatalytic conversions where there is potential for product racemisation.

| S-EPMC2854813 | biostudies-literature

Hexafluoroisopropanol as the Acid Component in the Passerini Reaction: One-Pot Access to ?-Amino Alcohols.

Project description:A new Passerini-type reaction in which hexafluoroisopropanol functions as the acid component is reported. The reaction tolerates a broad range of isocyanides and aldehydes, and the formed imidates can be reduced toward ?-amino alcohols under mild and metal-free conditions. In addition, the imidate products were shown to undergo an unprecedented retro-Passerini-type reaction under microwave conditions, providing valuable mechanistic information about the Passerini reaction and its variations.

| S-EPMC6038100 | biostudies-literature

Silica gel-immobilised chiral 1,2-benzenedisulfonimide: a Bronsted acid heterogeneous catalyst for enantioselective multicomponent Passerini reaction.

Project description:A chiral heterogeneous catalyst derivative of (-)-4,5-dimethyl-3,6-bis(1-naphthyl)-1,2-benzenedisulfonimide is proven here to be efficient in a three-component asymmetric Passerini protocol, carried out in a deep eutectic solvent. Reaction conditions are mild and green, while enantioselectivity is excellent. The catalyst was easily recovered and reused with no decrease in its catalytic activity.

| S-EPMC9037113 | 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