Synthesis Of Erythro Research Articles

Methyl 2-[(tert-Butoxycarbonyl)amino]-3-hydroxy-3-phenylpropanoate: Synthesis of Erythro (±) Isomer by Reduction and Threo (±) Isomer by Inversion Method

Methyl 2-[(tert-Butoxycarbonyl)amino]-3-hydroxy-3-phenylpropanoate: Synthesis of Erythro (±) Isomer by Reduction and Threo (±) Isomer by Inversion Method

Synthesis of erythro- B13 enantiomers and stereospecific action of full set of B13-isomers in MCF7 breast carcinoma cells: Cellular metabolism and effects on sphingolipids

B13 is an acid ceramidase (ACDase) inhibitor. The two chiral centers of this aromatic amido alcohol lead to four stereoisomers, yet we have little knowledge about its erythro- enantiomers, (1R, 2S) and (1S, 2R). In this paper, for the first time, the synthesis of two erythro- enantiomers is described, and the compounds are evaluated along with two threo- enantiomers, (1R, 2R) and (1S, 2S). The key metabolites and sphingolipid (SL) profile of the full set of B13 stereoisomers in MCF7 breast carcinoma cells are presented. The results demonstrated that the erythro- enantiomers were more effective than the threo- enantiomers on growth inhibition in MCF7 cells, although there were no statistically significant differences within the threo- and erythro- series. Measurement of intracellular levels of the compounds indicated that the erythro- seemed a little more cell permeable than the threo- enantiomers; also, the (1R, 2S) isomer with the same stereo structure as natural ceramide (Cer) could be hydrolyzed and phosphorylated in MCF7 cells. Furthermore, we also observed the formation of C16 homologs from the full set of B13 isomers within the cells, indicating the occurrence of de-acylation and re-acylation of the amino group of the aromatic alcohol. Moreover, the decrease in the Cer/Sph ratio suggests that the growth inhibition from (1R, 2S) isomer is not because of the inhibition of ceramidases. Taken together, (1R, 2S) could be developed as a substitute of natural Cer.

Photoactivable sphingosine as a tool to study membrane microenvironments in cultured cells

Human fibroblasts from normal subjects and Niemann-Pick A (NPA) disease patients were fed with two labeled metabolic precursors of sphingomyelin (SM), [(3)H]choline and photoactivable sphingosine, that entered into the biosynthetic pathway allowing the synthesis of radioactive phosphatidylcholine and SM, and of radioactive and photoactivable SM ([(3)H]SM-N(3)). Detergent resistant membrane (DRM) fractions prepared from normal and NPA fibroblasts resulted as highly enriched in [(3)H]SM-N(3). However, lipid and protein analysis showed strong differences between the two cell types. After cross-linking, different patterns of SM-protein complexes were found, mainly associated with the detergent soluble fraction of the gradient containing most cell proteins. After cell surface biotinylation, DRMs were immunoprecipitated using streptavidin. In conditions that maintain the integrity of domain, SM-protein complexes were detectable only in normal fibroblasts, whereas disrupting the membrane organization, these complexes were not recovered in the immunoprecipitate, suggesting that they involve proteins belonging to the inner membrane layer. These data suggest that differences in lipid and protein compositions of these cell lines determine specific lipid-protein interactions and different clustering within plasma membrane. In addition, our experiments show that photoactivable sphingolipids metabolically synthesized in cells can be used to study sphingolipid protein environments and sphingolipid-protein interactions.

ChemInform Abstract: Synthesis of erythro and threo Furanoid Glycals from 1‐ and 2‐Phenylselenenyl‐carbohydrate Derivatives.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthesis of erythro and threo furanoid glycals from 1- and 2-phenylselenenyl–carbohydrate derivatives

Differently protected erythro and threo furanoid glycals were synthesized by selenoxide elimination when phenyl 1-selenoglycosides were treated in oxidizing conditions ( t BuOOH, Ti(O i Pr) 4, Et 2 i PrN). The phenyl 1-selenoglycosides were obtained from methyl 2-deoxy- d- erythro-pentofuranoside by protection of the primary hydroxyl or both hydroxyls and further reaction with PhSeH in the presence of BF 3·Et 2O. Erythro and threo furanoid glycals were also prepared by treating 2-deoxy-2-phenylselenenyl-1,4-anhydrocyclitols under similar conditions. The 2-deoxy-2-phenylselenenyl-1,4-anhydrocyclitols were obtained from 4-pentene-1,2,3-triols by a 5-endo selenium electrophilic induced cyclization.

ChemInform Abstract: Synthesis of erythro and threo Furanoid Glycals Using 5‐endo‐Trig Selenoetherification as Key Step.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Synthesis of erythro and threo furanoid glycals using 5- endo-trig selenoetherification as key step

Differently protected erythro and threo furanoid glycals were synthesised from 4-pentene-1,2,3-triol, through selenium induced 5- endo-trig cyclization and selenoxide elimination.

Intramolecular S N2 ring opening of a cyclic sulfate: synthesis of erythro-(−)-6-acetoxy-5-hexadecanolide—a major component of mosquito oviposition attractant pheromone

Methyl trans-hexa-5-decenoate is dihydroxylated using AD-mix-α followed by treatment with thionyl chloride to furnish cyclic sulfite 8 as the major product. The cyclic sulfite 8 is oxidized to the cyclic sulfate 2. Highly regio- and stereospecific ring opening of (4 S,5 S)-carboxybutyl-5-decylcyclic sulfate generated in situ by the hydrolysis of 2 furnished (5 R,6 S)-6-hydroxy-5-hexadecanolide, 9 in high yield. Acetylation of 9 afforded natural oviposition attractant pheromone 1 in good yield.

Synthesis of erythro- ω-aminosphingosine and preparation of an affinity column for sphingosine kinase purification

The de novo synthesis of a C-17 erythro- ω-aminosphingosine homologue using L-serine is described together with its conjugation to Affi-Gel 10.

Synthesis, anti-GABA activity and preferred conformation of bicuculline and norbicuculline enantiomers

Synthesis of erythro-(±)-[1SR,9RS]-norbicuculline and threo-(±)-[1SR,9SR]-noradlumidine from piperonal was performed using Bischler-Napieralski cyclization as a key step. Resolution gave rise to (+)-[1S,9R]-norbicuculline ([1S,9R] norBIC) and (-)-[1R,9S]-norbicuculline ([1R,9S] norBIC) in >99.5% enantiomeric purity. Bicuculline enantiomers were readily obtained by methylation of the latter products. [1S,9R]BIC was about 70 times more potent than [1R,9S] BIC as an inhbitor of GABA(A) receptor binding and was about 100 and 900 times more potent than [1S,9R] norBIC at pH 7.1 and 5.0 respectively. Similarly, [1S,9R] norBIC was much less potent than [1S,9R] BIC as an inhibitor of GABA-specific (36)Cl(-) ion flux. The observed increase of about two orders of magnitude in the in vitro biological activity caused by N2-CH(3) substitution in [1S,9R] norBIC was attributed to different conformations for erythro- and nor-erythro-bicucullines indicated by (1)H nuclear Overhauser enhancements of [1S,9R] BIC and [1S,9R] norBIC.

Synthesis of N-protected erythro-phenylalanylepoxides

Abstract The synthesis of erythro -isomers of N-α-t-Boc, N-α-Fmoc- and N-α-Cbz-L-phenylalanylepoxides from the appropriate N-α-protected L-phenylalanines via bromomethylketone intermediates is described.

Acyclic stereoselection. 12. Double stereodifferentiation with mutual kinetic resolution. A superior class of reagents for control of Cram's rule stereoselection in synthesis of erythro-.alpha.-alkyl-.beta.-hydroxy carboxylic acids from chiral aldehydes

Acyclic stereoselection. 12. Double stereodifferentiation with mutual kinetic resolution. A superior class of reagents for control of Cram's rule stereoselection in synthesis of erythro-.alpha.-alkyl-.beta.-hydroxy carboxylic acids from chiral aldehydes

Stereospecific Synthesis of erythro- and threo-9,10-Diaminooctadecanoic Acids and Derivatives1

Stereospecific Synthesis of erythro- and threo-9,10-Diaminooctadecanoic Acids and Derivatives¹

Stereochemical studies. XVI. Stereospecific processes in open-chain 3-aminoalcohols. Synthesis of erythro- and threo-4-aminopentan-2-ol

Stereochemical studies. XVI. Stereospecific processes in open-chain 3-aminoalcohols. Synthesis of erythro- and threo-4-aminopentan-2-ol

Synthesis of erythro- and threo-α-Amino-β-hydroxystearic Acids1

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis of erythro- and threo-α-Amino-β-hydroxystearic Acids1H. E. Carter, J. B. Harrison, and David ShapiroCite this: J. Am. Chem. Soc. 1953, 75, 19, 4705–4709Publication Date (Print):October 1, 1953Publication History Published online1 May 2002Published inissue 1 October 1953https://doi.org/10.1021/ja01115a026RIGHTS & PERMISSIONSArticle Views225Altmetric-Citations24LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (682 KB) Get e-Alerts Get e-Alerts