Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Total synthesis of (±)-sorocenol B employing nanoparticle catalysis.

ABSTRACT: The total synthesis of (±)-sorocenol B has been accomplished featuring key steps including silver nanoparticle (AgNP)-catalyzed Diels-Alder cycloaddition and late-stage Pd(II)-catalyzed oxidative cyclization. The synthetic natural product exhibited low micromolar cytotoxic activity against a number of human cancer cell lines.

SUBMITTER: Cong H

PROVIDER: S-EPMC3434240 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Total synthesis of (±)-sorocenol B employing nanoparticle catalysis.

Cong Huan H Porco John A JA

Organic letters 20120503 10

The total synthesis of (±)-sorocenol B has been accomplished featuring key steps including silver nanoparticle (AgNP)-catalyzed Diels-Alder cycloaddition and late-stage Pd(II)-catalyzed oxidative cyclization. The synthetic natural product exhibited low micromolar cytotoxic activity against a number of human cancer cell lines. ...[more]

PMID: 22553903

Similar Datasets

Total Synthesis of Terpenoids Employing a "Benzannulation of Carvone" Strategy: Synthesis of (-)-Crotogoudin.

Project description:Carvone is a sustainable and readily available starting material for organic synthesis. Herein, we present the syntheses of various natural product scaffolds that rely on a novel benzannulation involving the ?-methyl group (C-10) of carvone to afford a versatile tetralin. The utility of our synthetic approach is highlighted by its application to a short synthesis of the ent-3,4-seco-atisane diterpenoid (-)-crotogoudin. The 13-step enantiospecific synthesis features a regioselective double oxidative dearomatization, a Diels-Alder cycloaddition with ethylene gas (to construct the bicyclo[2.2.2]octane framework), and a final acid-mediated lactonization. The versatility of this benzannulation strategy is demonstrated by its utility in the preparation of the carbon skeleton of ent-3,4-seco-abietane diterpenoids using an intramolecular oxidative dearomatization.

| S-EPMC6309435 | biostudies-literature

Total Synthesis of Scytonemide A Employing Weinreb AM Solid-Phase Resin.

Project description:The human 20S proteasome inhibitor scytonemide A (1), a macrocyclic imine originally isolated from the cyanobacterium Scytonema hofmanni, was synthesized via a biomimetic solid-phase peptide synthesis (SPPS) approach employing the Weinreb AM resin. Utilizing this approach, cyclization of the protected heptapeptide via formation of the imine bond occurred spontaneously upon cleavage from the resin in the presence of a reducing agent and subsequent aqueous workup. The final deprotection step necessary to produce the natural product was accomplished under slightly basic conditions, facilitating cleavage of the silyl ether group while leaving the macrocycle intact. Purification of the synthetic scytonemide A was accomplished via normal-phase flash column chromatography, potentially facilitating larger scale preparation of the compound necessary for future mechanistic and SAR studies. The structure of the target compound was confirmed by NMR spectroscopy, which also shed light on differences in the spectroscopic data obtained for the synthetic and natural scytonemide A samples for some of the amide and alcohol signals in the 1H NMR spectrum.

| S-EPMC5866229 | biostudies-literature

Asymmetric total synthesis of smyrindiol employing an organocatalytic aldol key step.

Project description:The first organocatalytic asymmetric synthesis of smyrindiol, by using an (S)-proline catalyzed enantioselective intramolecular aldol reaction as the key step, is described. Smyrindiol was synthesized from commercially available 2,4-dihydroxybenzaldehyde in 15 steps, with excellent stereoselectivity (de = 99%, ee = 99%). In the course of this total synthesis a new and mild coumarin assembly was developed.

| S-EPMC3458728 | biostudies-other

Orthogonal Nanoparticle Catalysis with Organogermanes.

Project description:Although nanoparticles are widely used as catalysts, little is known about their potential ability to trigger privileged transformations as compared to homogeneous molecular or bulk heterogeneous catalysts. We herein demonstrate (and rationalize) that nanoparticles display orthogonal reactivity to molecular catalysts in the cross-coupling of aryl halides with aryl germanes. While the aryl germanes are unreactive in Ln Pd0 /Ln PdII catalysis and allow selective functionalization of established coupling partners in their presence, they display superior reactivity under Pd nanoparticle conditions, outcompeting established coupling partners (such as ArBPin and ArBMIDA) and allowing air-tolerant, base-free, and orthogonal access to valuable and challenging biaryl motifs. As opposed to the notoriously unstable polyfluoroaryl- and 2-pyridylboronic acids, the corresponding germanes are highly stable and readily coupled. Our mechanistic and computational studies provide unambiguous support of nanoparticle catalysis and suggest that owing to the electron richness of aryl germanes, they preferentially react by electrophilic aromatic substitution, and in turn are preferentially activated by the more electrophilic nanoparticles.

| S-EPMC6899604 | biostudies-literature

Total Synthesis of (+)-SCH 351448: Efficiency via Chemoselectivity and Redox-Economy Powered by Metal Catalysis.

Project description:The polyketide natural product (+)-SCH 351448, a macrodiolide ionophore bearing 14 stereogenic centers, is prepared in 14 steps (LLS). In eight prior syntheses, 22-32 steps were required. Multiple chemoselective and redox-economic functional group interconversions collectively contribute to a step-change in efficiency.

| S-EPMC4935581 | biostudies-literature

Catalysis of Heterocyclic Azadiene Cycloaddition Reactions by Solvent Hydrogen Bonding: Concise Total Synthesis of Methoxatin.

Project description:Although it has been examined for decades, no general approach to catalysis of the inverse electron demand Diels-Alder reactions of heterocyclic azadienes has been introduced. Typically, additives such as Lewis acids lead to nonproductive consumption of the electron-rich dienophiles without productive activation of the electron-deficient heterocyclic azadienes. Herein, we report the first general method for catalysis of such cycloaddition reactions by using solvent hydrogen bonding of non-nucleophilic perfluoroalcohols, including hexafluoroisopropanol (HFIP) and trifluoroethanol (TFE), to activate the electron-deficient heterocyclic azadienes. Its use in promoting the cycloaddition of 1,2,3-triazine 4 with enamine 3 as the key step of a concise total synthesis of methoxatin is described.

| S-EPMC5042865 | biostudies-literature

Acetylene as a Dicarbene Equivalent for Gold(I) Catalysis: Total Synthesis of Waitziacuminone in One Step.

Project description:The gold(I)-catalyzed reaction of acetylene gas with alkenes leads to (Z,Z)-1,4-disubstituted 1,3-butadienes and biscyclopropanes depending on the donor ligand on gold(I). Acetylene was generated in situ from calcium carbide and water in a user-friendly procedure. Reaction of acetylene with 1,5-dienes gives rise stereoselectively to tricyclo[5.1.0.02,4 ]octanes. This novel double cyclopropanation has been applied to the one step total synthesis of the natural product waitziacuminone from acetylene and geranyl acetone.

| S-EPMC7078946 | biostudies-literature

Enantioselective total synthesis of (-)-minovincine in nine chemical steps: an approach to ketone activation in cascade catalysis.

Project description:Dressed to the nines: The first enantioselective total synthesis of (-)-minovincine has been accomplished in nine chemical steps and 13?% overall yield. A novel, one-step Diels-Alder/?-elimination/conjugate addition organocascade sequence allowed rapid access to the central tetracyclic core in an asymmetric manner. Boc=tert-butoxycarbonyl, LG=leaving group, PMB=para-methoxybenzyl.

| S-EPMC3934209 | biostudies-literature

Concise Total Synthesis of Lundurines A-C Enabled by Gold Catalysis and a Homodienyl Retro-Ene/Ene Isomerization.

Project description:The total synthesis of lundurines A-C has been accomplished in racemic and enantiopure forms in 11-13 and 12-14 steps, respectively, without protection/deprotection of functional groups, by a novel tandem double condensation/Claisen rearrangement, a gold(I)-catalyzed alkyne hydroarylation, a cyclopropanation via formal [3 + 2] cycloaddition/nitrogen extrusion, and a remarkable olefin migration through a vinylcyclopropane retro-ene/ene reaction that streamlines the endgame.

| S-EPMC4819460 | biostudies-literature

Employing a PLGA-TPGS based nanoparticle to improve the ocular delivery of Acyclovir.

Project description:Delivering drugs via the ocular route has always been a challenge for poorly soluble drugs. The various anatomical and physiological barriers in the eye cavity hinder the residence of drugs within the corneal and precorneal regions. In this study, the nanosystem that could sufficiently deliver the poorly soluble Acyclovir topically via ocular route. Our nanosystem is composed of the biocompatible PLGA polymer stabilized with TPGS which possess a high emulsifying capacity and is also known as P-gp inhibitor. The optimized nanoparticles were prepared with 0.3% TPGS and had particle-size of 262.3 nm, zeta-potential of +15.14 mV. The physicochemical-characterization, ex vivo transcorneal permeation, ocular-irritation and Acyclovir ocular-availability, following topical ocular application of PLGA-NPs in rabbit eyes, were performed. The tested parameters and irritation by Draize's test suggested the suitability and safety of PLGA-NPs for ocular use. An ultrahigh performance liquid chromatographic method was developed, validated, and applied to quantify Acyclovir in aqueous humor which was shown to be significantly higher (p < 0.05) using the developed nanoparticles as compared to Acyclovir-aqueous suspension following their single topical ocular administration. Noticeable 2.78-, 1.71- and 2.2-times increased values of AUC0-24h, t1/2 (h) and MRT0-24h were found, respectively, with the PLGA-TPGS-NPs as compared to ACY-AqS. These results demonstrate the superiority of delivering Acyclovir using a nanosystem compared to conventional methods.

| S-EPMC6362158 | 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