Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

An expeditious total synthesis of both diastereoisomeric lipid dihydroxytetrahydrofurans from Notheia anomala.

ABSTRACT: Short, high yielding syntheses of both diastereomers of the naturally occurring oxylipids 1 and 2 using a combination of organocatalytic hydroxylation of an aldehyde, alkene cross metathesis, and palladium(0) catalyzed cyclization chemistry (six-step process) are reported. Furthermore, the influence of the catalyst on the cross metathesis reaction of the homoallylic 1,2-diol has been studied in detail.

SUBMITTER: Roy S

PROVIDER: S-EPMC3345562 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

An expeditious total synthesis of both diastereoisomeric lipid dihydroxytetrahydrofurans from Notheia anomala.

Roy Sudeshna S Spilling Christopher D CD

Organic letters 20120416 9

Short, high yielding syntheses of both diastereomers of the naturally occurring oxylipids 1 and 2 using a combination of organocatalytic hydroxylation of an aldehyde, alkene cross metathesis, and palladium(0) catalyzed cyclization chemistry (six-step process) are reported. Furthermore, the influence of the catalyst on the cross metathesis reaction of the homoallylic 1,2-diol has been studied in detail. ...[more]

PMID: 22506757

Similar Datasets

An Expeditious Total Synthesis of 5'-Deoxy-toyocamycin and 5'-Deoxysangivamycin.

Project description:In present paper, an expeditious total synthesis of naturally occurring 5'-deoxytoyocamycin and 5'-deoxysangivamycin was accomplished. Because of the introduction of a benzoyl group at N-6 of 4-amino-5-cyano-6-bromo-pyrrolo[2,3-d]pyrimidine, a Vorbrüggen glycosylation with 1,2,3-tri-O-acetyl-5-deoxy-β-D-ribofuranose afforded a completely regioselective N-9 glycosylation product, which is unambiguously confirmed by X-ray diffraction analysis. All of the involved intermediates were well characterized by various spectra.

| S-EPMC6413189 | biostudies-literature

A macrolactonization approach to the total synthesis of the antimicrobial cyclic depsipeptide LI-F04a and diastereoisomeric analogues.

Project description:The cyclic peptide core of the antifungal and antibiotic cyclic depsipeptide LI-F04a was synthesised by using a modified Yamaguchi macrolactonization approach. Alternative methods of macrolactonization (e.g., Corey-Nicolaou) resulted in significant epimerization of the C-terminal amino acid during the cyclization reaction. The D-stereochemistry of the alanine residue in the naturally occurring cyclic peptide may be required for the antifungal activity of this natural product.

| S-EPMC3458759 | biostudies-literature

Expeditious Total Synthesis of Hemiasterlin through a Convergent Multicomponent Strategy and Its Use in Targeted Cancer Therapeutics.

Project description:Hemiasterlin is an antimitotic marine natural product with reported sub-nanomolar potency against several cancer cell lines. Herein, we describe an expeditious total synthesis of hemiasterlin featuring a four-component Ugi reaction (Ugi-4CR) as the key step. The convergent synthetic strategy enabled rapid access to taltobulin (HTI-286), a similarly potent synthetic analogue. This short synthetic sequence enabled investigation of both hemiasterlin and taltobulin as cytotoxic payloads in antibody-drug conjugates (ADCs). These novel ADCs displayed sub-nanomolar cytotoxicity against HER2-expressing cancer cells, while showing no activity against antigen-negative cells. This study demonstrates an improved synthetic route to a highly valuable natural product, facilitating further investigation of hemiasterlin and its analogues as potential payloads in targeted therapeutics.

| S-EPMC7756509 | biostudies-literature

Expeditious chemoenzymatic synthesis of CD52 glycopeptide antigens.

Project description:CD52 is a glycosylphosphatidylinositol (GPI)-anchored glycopeptide antigen found on sperm cells and human lymphocytes. Recent structural studies indicate that sperm-associated CD52 antigen carries both a complex type N-glycan and an O-glycan on the polypeptide backbone. To facilitate functional and immunological studies of distinct CD52 glycoforms, we report in this paper the first chemoenzymatic synthesis of homogeneous CD52 glycoforms carrying both N- and O-glycans. The synthetic strategy consists of two key steps: monosaccharide primers GlcNAc and GalNAc were first installed at the pre-determined N- and O-glycosylation sites by a facile solid-phase peptide synthesis, and then the N- and O-glycans were extended by respective enzymatic glycosylations. It was found that the endoglycosidase-catalyzed transglycosylation allowed efficient attachment of an intact N-glycan in a single step at the N-glycosylation site, while the recombinant human T-synthase could independently extend the O-linked GalNAc to form the core 1 O-glycan. This chemoenzymatic approach is highly convergent and permits easy construction of various homogeneous CD52 glycoforms from a common polypeptide precursor. In addition, the introduction of a latent thiol group in the form of protected cysteamine at the C-terminus of the CD52 glycoforms will enable site-specific conjugation to a carrier protein to provide immunogens for generating CD52 glycoform-specific antibodies for functional studies.

| S-EPMC3717399 | biostudies-literature

Expeditious, mechanochemical synthesis of BODIPY dyes.

Project description:BODIPY dyes have been synthesized under solvent-free or essentially solvent-free conditions, within about 5 minutes in an open-to-air setup by using a pestle and mortar, with yields that are comparable to those obtained via traditional routes that typically require reaction times of several hours to days.

| S-EPMC3678757 | biostudies-other

Expeditious Synthesis of Dianionic-Headed 4-Sulfoalkanoic Acid Surfactants.

Project description:4-Sulfoalkanoic acids are a class of important dianionic-headed surfactants. Various 4-sulfoalkanoic acids with straight C8, C10, C12, C14, C16, and C18 chains were synthesized expeditiously through the radical addition of methyl 2-((ethoxycarbonothioyl)thio)acetate to linear terminal olefins and subsequent oxidation with peroxyformic acid. This is a useful and convenient strategy for the synthesis of dianionic-headed surfactants with a carboxylic acid and sulfonic acid functionalities in the head group region.

| S-EPMC6154584 | biostudies-literature

Gold(I)-Catalyzed Aromatization: Expeditious Synthesis of Polyfunctionalized Naphthalenes.

Project description:A gold-catalyzed 6-endo-dig carbocyclization of alkyne with the pendent diazo group is reported. It provides an expeditious approach for the synthesis of multi-functionalized naphthalene derivatives under mild conditions. Mechanistic studies suggest that a vinyl gold carbene is generated as the key intermediate in this cascade transformation that smoothly delivers naphthalene products through an unprecedented stepwise aromatization or an intermolecular aromatic substitution process. The unique endocyclic vinyl species is inaccessible with other precursors; thus, novel carbene cascade transformations could be envisioned with the current catalytic model. Functional groups, such as alkenyl, hydroxyl, amino, and carboxyl groups, remain untouched under these conditions. In addition, the utility of these generated 2-carboxyl naphthalenes is illustrated by the synthesis of chiral 1,2'-binaphthalene ligands and π-conjugated polycyclic hydrocarbons (CPHs).

| S-EPMC6849331 | biostudies-literature

Diastereoisomeric analogues of gramicidin S: structure, biologicalactivity and interaction with lipid bilayers.

Project description:Analogues of a structurally equivalent version of theantimicrobial decameric cyclic peptide gramicidin S, GS10 [cyclo-(Val-Lys-Leu-d-Tyr-Pro)(2)], were designed to study theeffect of distortion in the beta-sheet/beta-turn structure of thecyclic peptide on its biological activity. In one approach, thehydrophobic nature of GS10 was conserved, and single amino acids in itsbackbone were replaced systematically with their correspondingenantiomers to give five diastereoisomeric analogues. In a relatedapproach, a more basic and hydrophilic analogue of GS10 [cyclo-(Lys-Val-Lys-d-Tyr-Pro(5)-Lys-Leu-Lys-d-Tyr-Pro(10))], together with two of itsmonosubstituted diastereoisomeric analogues (featuring d-Lys(1) or d-Val(2) respectively), weresynthesized. CD spectra were measured in a variety of environments,i.e. aqueous, aqueous trifluoroethanol and those containing SDSmicelles or phospholipid vesicles. In comparison with GS10 spectra, CDspectra of both groups of analogues in these environments exhibitedstructural distortion. Moreover, compared with GS10, antimicrobial andhaemolytic activities of the analogues were drastically decreased, implying the existence of a threshold minimum amphipathicity foreffective biological activity. However, in both groups of analogues,there was a correlation between amphipathicity and antimicrobial andhaemolytic activities. In the second group of analogues, bothelectrostatic and hydrophobic factors were related to theirantimicrobial and haemolytic activities. In order to gain an insightinto the nature of the biological activity of the two classes of cyclicpeptides, the relationship of their structure to interaction with lipidmembranes, and the implied mechanisms, were analysed in some detail inthe present study.

| S-EPMC1221201 | biostudies-other

Expeditious chemoenzymatic synthesis of homogeneous N-glycoproteins carrying defined oligosaccharide ligands.

Project description:An efficient chemoenzymatic method for the construction of homogeneous N-glycoproteins was described that explores the transglycosylation activity of the endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (Endo-A) with synthetic sugar oxazolines as the donor substrates. First, an array of large oligosaccharide oxazolines were synthesized and evaluated as substrates for the Endo-A-catalyzed transglycosylation by use of ribonuclease B as a model system. The experimental results showed that Endo-A could tolerate modifications at the outer mannose residues of the Man3GlcNAc-oxazoline core, thus allowing introduction of large oligosaccharide ligands into a protein and meanwhile preserving the natural, core N-pentasaccharide (Man3GlcNAc2) structure in the resulting glycoprotein upon transglycosylation. In addition to ligands for galectins and mannose-binding lectins, azido functionality could be readily introduced at the N-pentasaccharide (Man3GlcNAc2) core by use of azido-containing Man3GlcNAc oxazoline as the donor substrate. The introduction of azido functionality permits further site-specific modifications of the resulting glycoproteins, as demonstrated by the successful attachment of two copies of alphaGal epitopes to ribonuclease B. This study reveals a broad substrate specificity of Endo-A for transglycosylation, and the chemoenzymatic method described here points to a new avenue for quick access to various homogeneous N-glycoproteins for structure-activity relationship studies and for biomedical applications.

| S-EPMC2662341 | biostudies-literature

An Expeditious and Greener Synthesis of 2-Aminoimidazoles in Deep Eutectic Solvents.

Project description:A high-yield one-pot two-step synthesis of 2-aminoimidazoles (2-AI), exploiting an under-air heterocyclodehydration process between ?-chloroketones and guanidine derivatives, and using deep eutectic solvents (DESs) as nonconventional, "green" and "innocent" reaction media, has been accomplished successfully. The combination of either glycerol or urea with choline chloride (ChCl) proved to be effective for decreasing the reaction time to about 4-6 h in contrast to the 10-12 h usually required for the same reaction run in toxic and volatile organic solvents and under an argon atmosphere. In addition, the use of the ChCl-urea as a DES also enables the direct isolation of triaryl-substituted 2-AI derivatives by means of a simple work-up procedure consisting in filtration and crystallization, and allows the recycle of the DES mixture. A plausible mechanism highlighting the potential role played by hydrogen bonding catalysis has also been illustrated.

| S-EPMC6273198 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

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