Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Oxidative conversion of ?-sultones to ?-lactones.

ABSTRACT: Delta-sultones, prepared by C-H insertion, can be oxidatively converted to gamma-lactones by treatment with t-BuOK/t-BuOOH. An intermediate in the synthesis of (-)-eburnamonin was prepared using this approach.

SUBMITTER: Liyanage DS

PROVIDER: S-EPMC4465188 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Oxidative conversion of δ-sultones to γ-lactones.

Liyanage Duminda S DS Jungong Christian S CS Novikov Alexei V AV

Tetrahedron letters 20150401 17

Delta-sultones, prepared by C-H insertion, can be oxidatively converted to gamma-lactones by treatment with t-BuOK/t-BuOOH. An intermediate in the synthesis of (-)-eburnamonin was prepared using this approach. ...[more]

PMID: 26085691

Similar Datasets

Synthesis, Characterization, Cytotoxicity, and Antibacterial Properties of <i>trans</i>-γ-Halo-δ-lactones.

Project description:A new four-step pathway for the synthesis of γ-halo-δ-lactones is described from simple, commercially available substrates: aryl bromides and 3-methyl crotonaldehyde. The halogenolactonization reaction of β,δ-substituted, γ,δ-unsaturated carboxylic acid 4 a-c is regio- and stereoselective and gives only the trans-isomers of lactones 5 a-c, 6 a-c, and 7 a-c. The structures of all synthesized compounds were confirmed by using spectroscopic methods. For bromolactone, containing a naphthyl moiety in the structure, crystallographic analysis was also performed. The lactones were tested for their cytotoxic activity against L929 cell lines (mouse fibroblasts) and antibacterial activity against Escherichia coli strains ATCC 8739 and Staphylococcus aureus ATCC 65389. Compounds 5 a, 5 c, 7 a, and 7 b statistically significantly inhibited the metabolic activity of mouse fibroblasts L929. Compounds 5 b and 6 a were not cytotoxic towards L929 cells, but showed moderate bactericidal properties.

| S-EPMC6055027 | biostudies-literature

Carbonylation of epoxides to substituted 3-hydroxy-delta-lactones.

Project description:Substituted 3-hydroxy-delta-lactones (3HLs) are valuable intermediates in the synthesis of pharmaceuticals and other biologically active natural products. Herein we report the first example of the catalytic carbonylation of substituted homoglycidols to 3HLs using HCo(CO)4. Upon optimization of the catalyst and reaction conditions, a functionally diverse set of 3HLs was prepared. Mechanistic insight was gained by observation of the carbonylation reaction using in situ IR spectroscopy, and we propose a mechanism that is consistent with previously studied epoxide carbonylation systems.

| S-EPMC2596996 | biostudies-literature

Chemoenzymatic Synthesis of Enantiomeric, Bicyclic δ-Halo-γ-lactones with a Cyclohexane Ring, Their Biological Activity and Interaction with Biological Membranes.

Project description:Starting from 1-acetyl-1-cyclohexene, three enantiomeric pairs (ee ≥99%) of bicyclic δ-halo-γ-lactones with cyclohexane ring were obtained in five-step synthesis. The key stereochemical steps were lipase-catalyzed kinetic resolution of racemic 1-(cyclohex-1-en-1-yl) ethanol followed by transfer of chirality to ethyl 2-(2-ethylidenecyclohexyl) acetate in the Johnson-Claisen rearrangement. Synthesized halolactones exhibited antiproliferative activity towards canine B-cell leukemia cells (GL-1) and canine B-cell chronic leukemia cells (CLB70) and the most potent (IC50 18.43 ± 1.46 μg/mL against GL-1, IC50 11.40 ± 0.40 μg/mL against CLB70) comparable with the control etoposide, was (1R,6R,1'S)-1-(1'-chloroethyl)-9- oxabicyclo[4.3.0]nonan-8-one (8b). All halolactones did not have a toxic effect on erythrocytes and did not change the fluidity of membranes in the hydrophobic region of the lipid bilayer. Only weak changes in the hydrophilic area were observed, like the degree of lipid packing and associated hydration. The racemic halolactones were also tested for their antimicrobial properties and found to exhibit selectivity towards bacteria, in particular, towards Proteus mirabilis ATCC 35659.

| S-EPMC7022392 | biostudies-literature

Oxidative metabolism of linoleic acid modulates PPAR-beta/delta suppression of PPAR-gamma activity.

Project description:Peroxisome proliferator-activated receptors (PPARs) are transcription factors that strongly influence molecular events in normal and cancer cells. PPAR-beta/delta (PPAR-b/d) overexpression suppresses the activity of PPAR-gamma (PPAR-g) and PPAR-alpha. This interaction has been questioned, however, by studies with synthetic ligands of PPARs in PPAR-b/d-null cells, and it is not known whether an interaction between PPAR-b/d and PPAR-g exists, especially in relation to the signaling by natural PPAR ligands. Oxidative metabolites of linoleic and arachidonic acids are natural ligands of PPARs. 13-S-hydroxyoctadecadienoic acid (13-S-HODE), the main product of 15-lipoxygenase-1 (15-LOX-1) metabolism of linoleic acid, downregulates PPAR-b/d. We tested (a) whether PPAR-b/d expression modulates PPAR-g activity in experimental models of the loss and gain of PPAR-b/d function in colon cancer cells and (b) whether 15-LOX-1 formation of 13-S-HODE influences the interaction between PPAR-b/d and PPAR-g. We found that (a) 15-LOX-1 formation of 13-S-HODE promoted PPAR-g activity, (b) PPAR-b/d expression suppressed PPAR-g activity in models of both loss and gain of PPAR-b/d function, (c) 15-LOX-1 activated PPAR-g by downregulating PPAR-b/d, and (d) 15-LOX-1 expression induced apoptosis in colon cancer cells via modulating PPAR-b/d suppression of PPAR-g. These findings elucidate a novel mechanism of the signaling by natural ligands of PPARs, which involves modulating the interaction between PPAR-b/d and PPAR-g.

| S-EPMC1432095 | biostudies-literature

LIMES Gamma Delta Data Access Commitee

Project description:Data Access Committee EGAC00001003406

| EGAC00001003406 | EGA

Biotechnological formation of dairy flavor inducing δ-lactones from vegetable oil.

Project description:Agroscope Culture Collection was screened to identify bacterial strains effective in production of dairy flavor inducing lactones using grapeseed oil as a substrate. Lentilactobacillus parafarraginis FAM-1079, Lactococcus lactis subsp. lactis FAM-17918, and L. lactis subsp. lactis biovar diacetylactis FAM-22003 showed the most efficient formation of targeted δ-lactones. The application of sublethal heat stress significantly increased target lactone production. The most profound improvement was for L. lactis subsp. lactis biovar diacetylactis where δ-octadecalactone generation was improved by factor of 9. The pre-fermentation step as well as growth phase in which bacteria are harvested did not have a significant impact on lactones yield. The lactone production process from vegetable oil developed in this study offers a new way of developing a natural flavor ingredient for incorporation into plant-based products.

| S-EPMC9039933 | biostudies-literature

Polarity inversion of donor-acceptor cyclopropanes: disubstituted δ-lactones via enantioselective iridium catalysis.

Project description:The coupling of carbonyl electrophiles at the donor position of donor-acceptor cyclopropanes is described, representing an inversion of polarity with respect to conventional reactivity modes displayed by these reagents. Specifically, upon exposure of donor-acceptor cyclopropanes to alcohols in the presence of a cyclometalated iridium catalyst modified by (S)-BINAP, catalytic C-C coupling occurs, providing enantiomerically enriched products of carbonyl allylation. Identical products are obtained upon isopropanol-mediated transfer hydrogenation of donor-acceptor cyclopropanes in the presence of aldehydes. The reaction products are directly transformed to cis-4,5-disubstituted δ-lactones.

| S-EPMC3218199 | biostudies-literature

Thiomaleic anhydride: a convenient building block for the synthesis of alpha-substituted gamma- and delta-lactones through free-radical addition, nucleophilic ring opening, and subsequent thiocarboxylate manipulation.

Project description:Iodoalkyl tert-butyl carbonates and carbamates undergo clean free-radical addition to thiomaleic anhydride to give substituted thiosuccinic anhydrides in high yield on treatment with tris(trimethylsilyl)silane and a radical initiator. After removal of the tert-butyloxycarbonyl group, cyclization then affords lactones or lactams substituted in the alpha-position by a thiocarboxylic acid residue. This group is converted to amides through reaction with electron-deficient sulfonamides or to aldehydes and/or ketones by the reaction of derived thioesters with either thiophenol, an electron-deficient allyl phenyl sulfide, or phenylboronic acid.

| S-EPMC2778001 | biostudies-literature

An Enzymatic Platform for the Highly Enantioselective and Stereodivergent Construction of Cyclopropyl-δ-lactones.

Project description:Abiological enzymes offers new opportunities for sustainable chemistry. Herein, we report the development of biological catalysts derived from sperm whale myoglobin that exploit a carbene transfer mechanism for the asymmetric synthesis of cyclopropane-fused-δ-lactones, which are key structural motifs found in many biologically active natural products. While hemin, wild-type myoglobin, and other hemoproteins are unable to catalyze this reaction, the myoglobin scaffold could be remodeled by protein engineering to permit the intramolecular cyclopropanation of a broad spectrum of homoallylic diazoacetate substrates in high yields and with up to 99 % enantiomeric excess. Via an alternate evolutionary trajectory, a stereodivergent biocatalyst was also obtained for affording mirror-image forms of the desired bicyclic products. In combination with whole-cell transformations, the myoglobin-based biocatalyst was used for the asymmetric construction of a cyclopropyl-δ-lactone scaffold at a gram scale, which could be further elaborated to furnish a variety of enantiopure trisubstituted cyclopropanes.

| S-EPMC8346518 | biostudies-literature

Comparative analysis of D. shibae wild-type vs. delta-luxI1 supplemented with different acetylated homoserine-lactones

Project description:Comparison of a quorum sensing null mutant supplemented with C18-HSL, C18en-HSL, C18dien-HSL with D. shibae wild-type in order to identify traits induced by distinct autoinducers in this organism.

2012-11-03 | GSE42010 | GEO

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