Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Total syntheses and structural revision of alpha- and beta-diversonolic esters and total syntheses of diversonol and blennolide C.

ABSTRACT:

SUBMITTER: Nicolaou KC

PROVIDER: S-EPMC2790823 | biostudies-literature | 2008

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Total syntheses and structural revision of alpha- and beta-diversonolic esters and total syntheses of diversonol and blennolide C.

Nicolaou K C KC Li Ang A

Angewandte Chemie (International ed. in English) 20080101 35

PMID: 18651685

Similar Datasets

Total synthesis and structural revision of engelhardione.

Project description:The total synthesis of the macrocyclic natural product engelhardione is reported. This effort led to the structural revision of the published structure of engelhardione to that of pterocarine. The revision reflects the change of the substitution pattern of one phenyl ether ring from the meta to the para position. To confirm, pterocarine (2) and its close regioisomer 3 were subsequently synthesized for comparison. Moreover, to the best of our knowledge, our synthesis of 1 represents the first example of a 14-membered macrocyclic diarylheptanoid with a meta-meta substitution pattern at the diphenyl ether moiety.

| S-EPMC3171739 | biostudies-literature

Enantioselective total syntheses of citrinadins A and B. Stereochemical revision of their assigned structures.

Project description:The concise, enantioselective total syntheses of (-)-citrinadin A and (+)-citrinadin B in a total of only 20 and 21 steps, respectively, from commercially available starting materials are described. Our strategy, which minimizes refunctionalization and protection/deprotection operations, features the highly diastereoselective, vinylogous Mannich addition of a dienolate to a chiral pyridinium salt to set the first chiral center. The absolute stereochemistry of this key center was then relayed by a sequence of substrate-controlled reactions, including a highly stereoselective epoxidation/ring opening sequence and an oxidative rearrangement of an indole to furnish a spirooxindole to establish the remaining stereocenters in the pentacyclic core of the citrinadins. An early stage intermediate in the synthesis of (-)-citrinadin A was deoxygenated to generate a dehydroxy compound that was elaborated into (+)-citrinadin B by a sequence of reaction identical to those used to prepare (-)-citrinadin A. These concise syntheses of (-)-citrinadin A and (+)-citrinadin B led to a revision of their stereochemical structures.

| S-EPMC4195386 | biostudies-literature

Cryptocaryols A and B: total syntheses, stereochemical revision, structure elucidation, and structure-activity relationship.

Project description:The first total syntheses and structural elucidation of cryptocaryol A and cryptocaryol B were achieved in 23 and 25 linear steps, respectively. The synthesis relied on the use of a key pseudo-Cs symmetric pentaol intermediate, which in a stereochemically divergent manner was converted into either enantiomer as well as diastereomers. This synthetic effort enabled the first structure-activity relationships of this class of PDCD4 stabilizing natural products.

| S-EPMC3772640 | biostudies-literature

Stereoselective Syntheses of α,β-Unsaturated γ-Amino Esters Through Phosphine-Catalyzed γ-Umpolung Additions of Sulfonamides to γ-Substituted Allenoates.

Project description:α,β-Unsaturated γ-amino esters can be synthesized efficiently and stereoselectively through phosphine-catalyzed γ-umpolung additions of sulfonamides to γ-substituted allenoates. The structures of the sulfonamide and γ-substituted allenoate partners can be varied to achieve a range of α,β-unsaturated γ-amino esters with potentially interesting chemical and biological properties.

| S-EPMC4450090 | biostudies-literature

Asymmetric synthesis of anti-β-amino-α-hydroxy esters via dynamic kinetic resolution of β-amino-α-keto esters.

Project description:A method for the asymmetric synthesis of enantioenriched anti-α-hydroxy-β-amino acid derivatives by enantioconvergent reduction of the corresponding racemic α-keto esters is presented. The requisite α-keto esters are prepared via Mannich addition of ethyl diazoacetate to imines followed by oxidation of the diazo group with Oxone. Implementation of a recently developed dynamic kinetic resolution of β-substituted-α-keto esters via Ru(II)-catalyzed asymmetric transfer hydrogenation provides the title motif in routinely high diastereo- and enantioselectivity.

| S-EPMC3766400 | biostudies-literature

Total synthesis and structural revision of biyouyanagin B.

Project description: Not available

| S-EPMC3023179 | biostudies-literature

Total synthesis and structural revision of viridicatumtoxin B.

Project description: Not available

| S-EPMC3835450 | biostudies-literature

Total synthesis and structural revision of lucentamycin A.

Project description:Lucentamycin A is a marine-derived peptide natural product harboring a unique 4-ethylidene-3-methylproline (Emp) subunit. The proposed structure of lucentamycin A and the core Emp residue have recently been called into question through synthesis. Here, we report the first total synthesis of lucentamycin A, which confirms that the ethylidene substituent in Emp bears an E geometry, in contrast to the originally assigned Z configuration. Synthesis of the desired (E)-Emp subunit required the implementation of a novel strategy starting from Garner's aldehyde.

| S-EPMC5525334 | biostudies-literature

Copper-catalyzed cascade reactions of α,β-unsaturated esters with keto esters.

Project description:A copper-catalyzed cascade reaction of α,β-unsaturated esters with keto esters is reported. It features a copper-catalyzed reductive aldolization followed by a lactonization. This method provides a facile approach to prepare γ-carboxymethyl-γ-lactones and δ-carboxymethyl-δ-lactones under mild reaction conditions.

| S-EPMC4362015 | biostudies-literature

Callipeltosides A, B and C: Total Syntheses and Structural Confirmation.

Project description:Since their isolation almost 20 years ago, the callipeltosides have been of long standing interest to the synthetic community owing to their unique structural features and inherent biological activity. Herein we present our full research effort that has led to the synthesis of these molecules. Key aspects of our final strategy include 1) synthesis of the C1-C9 pyran core (5) using an AuCl3 -catalysed cyclisation; 2) formation of C10-C22 vinyl iodide (55) by sequential bidirectional Stille reactions and 3) diastereoselective union of these advanced fragments by means of an alkenylzinc addition (d.r.=91:9 at C9). The common callipeltoside aglycon (4) was completed in a further five steps. Following this, all three sugar fragments were appended to provide the entire callipeltoside family. In addition to this, D-configured callipeltose B was synthesised and appended to the callipeltoside aglycon. The (1) H NMR spectrum of this molecule was found to be significantly different to the natural isolate, further supporting our assignment of callipeltoside B (2).

| S-EPMC4583783 | 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