Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Synthetic studies toward mannopeptimycin-E: synthesis of the O-linked tyrosine 1,4-alpha,alpha-manno,manno-pyranosyl pyranoside.

ABSTRACT: [structure: see text] The enantioselective synthesis of the C-4' acylated 1,4-alpha,alpha-manno,manno-disaccharide fragment of mannopeptimycin-E has been achieved in seven steps from d-tyrosine. The route relies upon diastereoselective palladium-catalyzed glycosylation, diastereoselective reduction, and diastereoselective bis-dihydroxylation. The efficiency of the synthesis is demonstrated by the high overall yield (37%) and the preparation of various analogues.

SUBMITTER: Babu RS

PROVIDER: S-EPMC2631387 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Synthetic studies toward mannopeptimycin-E: synthesis of the O-linked tyrosine 1,4-alpha,alpha-manno,manno-pyranosyl pyranoside.

Babu Ravula Satheesh RS Guppi Sanjeeva R SR O'Doherty George A GA

Organic letters 20060401 8

[structure: see text] The enantioselective synthesis of the C-4' acylated 1,4-alpha,alpha-manno,manno-disaccharide fragment of mannopeptimycin-E has been achieved in seven steps from d-tyrosine. The route relies upon diastereoselective palladium-catalyzed glycosylation, diastereoselective reduction, and diastereoselective bis-dihydroxylation. The efficiency of the synthesis is demonstrated by the high overall yield (37%) and the preparation of various analogues. ...[more]

PMID: 16597121

Similar Datasets

Stereocontrolled synthesis of the D- and L-glycero-beta-D-manno-heptopyranosides and their 6-deoxy analogues. Synthesis of methyl alpha-l-rhamno-pyranosyl-(1-->3)-D-glycero-beta-D-manno-heptopyranosyl- (1-->3)-6-deoxy-glycero-beta-D-manno-heptopyranosyl-(1-->4)-alpha-L- rhamno-pyranoside, a tetrasaccharide subunit of the lipopolysaccharide from Plesimonas shigelloides.

Project description:The synthesis of d- and l-glycero-alpha-manno-thioheptopyranosides, protected with 4,6-O-alkylidene-type acetals is described. In glycosylations carried out with preactivation with the 1-benzenesulfinylpiperidine/trifluoromethanesulfonic anhydride couple, both the D- and L-glycero series exhibit excellent beta-selectivity with a range of glycosyl acceptors. In contrast, a 4,7-O-alkylidene acetal was found not to afford beta-selectivity. With a 4,6-O-[1-cyano-2-(2-iodophenyl)ethylidene] acetal protected thioglycoside, excellent beta-selectivity was obtained in glycosylation reactions, and subsequent treatment with tributyltin hydride and azoisobutyronitrile brought about clean fragmentation to the 6-deoxy-glycero-beta-D-manno-heptopyranosides. This chemistry was applied to the stereocontrolled synthesis of methyl alpha-L-rhamno-pyranosyl-(1-->3)-D-glycero-beta-D-manno-heptopyranosyl-(1-->3)-6-deoxy-glycero-beta-D-manno-heptopyranosyl-(1-->4)-alpha-L-rhamno-pyranoside, a component of the lipopolysaccharide from Plesimonas shigelloides.

| S-EPMC2617734 | biostudies-literature

Diastereoselective synthesis of cyclopentapyridazinones via radical cyclization: synthetic studies toward halichlorine.

Project description:The pyridazinone ring system serves as an excellent scaffold for the diastereoselective preparation of novel cis-fused cyclopentapyridazinones utilizing the directed 5-exo radical cyclization approach. This overall approach was successfully employed in the preparation of a functionalized aza-spirocycle.

| S-EPMC2745910 | biostudies-literature

Synthetic studies toward the mannopeptimycins: synthesis of orthogonally protected beta-hydroxyenduracididines.

Project description:The asymmetric synthesis of the nonproteinogenic amino acids (2S,3S,4'S)-beta-hydroxyenduracididine 3 and (2R,3S,4'S)-beta-hydroxyenduracididine 4 in orthogonally protected form in 15 total steps from Garner's aldehyde is reported. The former and N-glycosylated form of the latter are found in the glycopeptide antibiotic mannopeptimycin.

| S-EPMC2871400 | biostudies-literature

Synthetic studies toward (+)-cortistatin A.

Project description:We describe herein the synthesis of a late-stage intermediate en route to cortistatin A. Key transformations included a Snieckus-like cascade sequence culminating in a 6?-electrocyclization, an alkylative dearomatization, and the stereoselective functionalization of the cortistatin A-ring. While the total synthesis we sought was not accomplished, the work sets the stage for several approaches to the preparation of novel analogs via diverted total synthesis.

| S-EPMC3413295 | biostudies-literature

Synthetic studies toward lapidilectine-type Kopsia alkaloids.

Project description:A rapid synthesis of the tetracyclic core of Kopsia indole alkaloids related to lapidilectine B, grandilodine C, and tenuisine A is reported. Key to the success of this route was an efficient and scalable Ugi four-component coupling to install all the necessary carbons found in the natural products.

| S-EPMC3262909 | biostudies-literature

Synthetic studies toward Mycobacterium tuberculosis sulfolipid-I.

Project description:Sulfolipid-I (SL-I) is an abundant metabolite found in the cell wall of Mycobacterium tuberculosis that is comprised of a trehalose 2-sulfate core modified with four fatty acyl substituents. The correlation of its abundance with the virulence of clinical isolates suggests a role for SL-I in pathogenesis, although its biological functions remain unknown. Here we describe the synthesis of a SL-I analogue bearing unnatural lipid substituents. A key feature of the synthesis was application of an intramolecular aglycon delivery reaction to join two differentially protected glucose monomers, one prepared with a novel alpha-selective glycosylation. The route developed for the model compound can be readily extended to the synthesis of native SL-I as well as additional analogues for use in the investigation of SL-I's functions.

| S-EPMC2735189 | biostudies-other

Chemoenzymatic and Protecting-Group-Free Synthesis of 1,4-Substituted 1,2,3-Triazole-α-d-glucosides with Potent Inhibitory Activity toward Lysosomal α-Glucosidase.

Project description:α-Glucosyl triazoles have rarely been tested as α-glucosidase inhibitors, partly due to inefficient synthesis of their precursor α-d-glucosylazide (αGA1). Glycosynthase enzymes, made by nucleophile mutations of retaining β-glucosidases, produce αGA1 in chemical rescue experiments. Thermoanaerobacterium xylanolyticus glucosyl hydrolase 116 β-glucosidase (TxGH116) E441G nucleophile mutant catalyzed synthesis of αGA1 from sodium azide and pNP-β-d-glucoside (pNPGlc) or cellobiose in aqueous medium at 45 °C. The pNPGlc and azide reaction product was purified by Sephadex LH-20 column chromatography to yield 280 mg of pure αGA1 (68% yield). αGA1 was successfully conjugated with alkynes attached to different functional groups, including aryl, ether, amine, amide, ester, alcohol, and flavone via copper-catalyzed azide-alkyne cycloaddition (CuAAC) click chemistry reactions. These reactions afforded the 1,4-substituted 1,2,3-triazole-α-d-glucoside derivatives AGT2-14 without protection and deprotection. Several of these glucosyl triazoles exhibited strong inhibition of human lysosomal α-glucosidase, with IC50 values for AGT4 and AGT14 more than 60-fold lower than that of the commercial α-glucosidase inhibitor acarbose.

| S-EPMC8495876 | biostudies-literature

Synthetic studies toward the citrinadin A and B core architecture.

Project description:The core architecture of the citrinadin alkaloids has been prepared in racemic form by utilizing a strategy that exploits the alkylation of 2-methoxypyridines. An initially planned indolizidine to quinolizidine transformation to build the D/E rings was unsuccessful. Success was ultimately gained by a direct alkylation to establish the citrinadin core architecture.

| S-EPMC3829995 | biostudies-literature

Crystal structure of methyl α-l-rhamno-pyranosyl-(1→2)-α-l-rhamno-pyran-oside monohydrate.

Project description:The title compound, C13H24O9·H2O, a structural model for part of bacterial O-anti-gen polysaccharides from Shigella flexneri and Escherichia coli, crystallizes with four independent disaccharide mol-ecules and four water mol-ecules in the asymmetric unit. The conformation at the glycosidic linkage joining the two rhamnosyl residues is described by the torsion angles φH of 39, 30, 37 and 37°, and ψH of -32, -35, -31 and -32°, which are the major conformation region known to be populated in an aqueous solution. The hexo-pyran-ose rings have the 1 C 4 chair conformation. In the crystal, the disaccharide and water mol-ecules are associated through O-H⋯O hydrogen bonds, forming a layer parallel to the bc plane. The layers stack along the a axis via hydro-phobic inter-actions between the methyl groups.

| S-EPMC6658941 | biostudies-literature

Studies toward the synthesis of maoecrystal V.

Project description:An approach toward the synthesis of maoecrystal V is described. The synthetic strategy for this approach was designed to address unique challenges posed by the strained tetrahydrofuran ring at the center of the target structure.

| S-EPMC3373731 | 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