Category: 3976-69-0

Siedler, Solvej; Bringer, Stephanie; Polen, Tino; Bott, Michael published an article in 2014, the title of the article was NADPH-dependent reductive biotransformation with Escherichia coli and its pfkA deletion mutant: Influence on global gene expression and role of oxygen supply.Application of 3976-69-0 And the article contains the following content:

An Escherichia coli ΔpfkA mutant lacking the major phosphofructokinase possesses a partially cyclized pentose phosphate pathway leading to an increased NADPH per glucose ratio. This effect decreases the amount of glucose required for NADPH regeneration in reductive biotransformations, such as the conversion of Me acetoacetate (MAA) to (R)-Me 3-hydroxybutyrate (MHB) by an alc. dehydrogenase from Lactobacillus brevis. Here, global transcriptional analyses were performed to study regulatory responses during reductive biotransformation. DNA microarray anal. revealed amongst other things increased expression of soxS, supporting previous results indicating that a high NADPH demand contributes to the activation of SoxR, the transcriptional activator of soxS. Furthermore, several target genes of the ArcAB two-component system showed a lower mRNA level in the reference strain than in the ΔpfkA mutant, pointing to an increased QH2/Q ratio in the reference strain. This prompted us to analyze yields and productivities of MAA reduction to MHB under different oxygen regimes in a bioreactor. Under anaerobic conditions, the specific MHB production rates of both strains were comparable (7.4 ± 0.2 mmolMHB h-1 gcdw-1) and lower than under conditions of 15% dissolved oxygen, where those of the reference strain (12.8 mmol h-1 gcdw-1) and of the ΔpfkA mutant (11.0 mmol h-1 gcdw-1) were 73% and 49% higher. While the oxygen transfer rate (OTR) of the reference strain increased after the addition of MAA, presumably due to the oxidation of the acetate accumulated before MAA addition, the OTR of the ΔpfkA strain strongly decreased, indicating a very low respiration rate despite sufficient oxygen supply. The latter effect can likely be attributed to a restricted conversion of NADPH into NADH via the soluble transhydrogenase SthA, as the enzyme is outcompeted in the presence of MAA by the recombinant NADPH-dependent alc. dehydrogenase. The differences in respiration rates can explain the suggested higher ArcAB activity in the reference strain. Biotechnol. Bioeng. 2014;9999: 1-9. © 2014 Wiley Periodicals, Inc. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Application of 3976-69-0

The Article related to escherichia reductive biotransformation oxygen supply gene expression, dna microarrays, escherichia coli, stha transhydrogenase, phosphofructokinase, reductive whole-cell biotransformation, resting cells and other aspects.Application of 3976-69-0

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Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

On January 13, 2014, Klitzke, Joice S.; Roisnel, Thierry; Kirillov, Evgeny; de L. Casagrande, Osvaldo Jr.; Carpentier, Jean-Francois published an article.Product Details of 3976-69-0 The title of the article was Yttrium- and Aluminum-Bis(phenolate)pyridine Complexes: Catalysts and Model Compounds of the Intermediates for the Stereoselective Ring-Opening Polymerization of Racemic Lactide and β-Butyrolactone. And the article contained the following:

Yttrium and aluminum complexes of an original pyridine-bis-(phenolate) ligand were prepared Reactions of {ONOMe,Cumyl}-Y-[N-(SiHMe2)2](THF)(Et2O) (1) with 1 equiv of Me-(R)-3-hydroxybutyrate and Me (S,S)-lactyllactate afforded resp. {ONOMe,Cumyl}-Y-((R)-OCH-Me-CH2COOMe) (2) and {ONOMe,Cumyl}-Y-((S,S)-OCH-Me-CO2CH-Me-CO2Me) (3), which are rare models of the active species in the ring-opening polymerization (ROP) of β-butyrolactone (BBL) and lactide (LA), resp. 13C NMR data for 2 and 3 indicate that, in solution, the carbonyl groups coordinate onto the yttrium centers, forming mononuclear species with six- and five-membered cycles, resp. The aluminum compounds {ONOMe,Cumyl}-Al-(iPr-(S)-lactate) (5), {ONOMe,Cumyl}-Al-((R)-OCH-Me-CH2COOCH3) (6), and {ONOMe,Cumyl}-Al-((rac)-OCH-(CF3)-CH2CO2C2H5) (7) were prepared analogously from the parent Me complex {ONOMe,Cumyl}-AlMe (4). NMR data and the solid-state structure of 6 confirm the coordination of the carbonyl group. Yttrium compounds 1 and 2 are active initiators for the ROP of racemic LA and BBL. Their performances (activity, control of the mol. weights, tacticity) are much affected by the nature of the solvent or by the addition of just a few equivalent of pyridine. Optimal conditions are quite contrasted for the ROP of rac-LA and rac-BBL, highlighting fundamental differences between these two monomers. In the best cases, highly heterotactic PLAs (Pr up to 0.96) and syndiotactic-enriched PHB (Pr up to 0.86), with good control over the mol. weights, were obtained. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Product Details of 3976-69-0

The Article related to yttrium aluminum pyridinebisphenolato hydroxybutyrate lactyllactate complex preparation crystal structure, lactide butyrolactone polymerization yttrium aluminum pyridinebisphenolato hydroxybutyrate complex catalyst and other aspects.Product Details of 3976-69-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

On December 31, 2019, Rao, Jingxin; Zhang, Rongzhen; Liang, Hongbo; Gao, Xiao-Dong; Nakanishi, Hideki; Xu, Yan published an article.Electric Literature of 3976-69-0 The title of the article was Efficient chiral synthesis by Saccharomyces cerevisiae spore encapsulation of Candida parapsilosis Glu228Ser/(S)-carbonyl reductase II and Bacillus sp. YX-1 glucose dehydrogenase in organic solvents. And the article contained the following:

Background: Saccharomyces cerevisiae AN120 osw2Δ spores were used as a host with good resistance to unfavorable environment. This work was undertaken to develop a new yeast spore-encapsulation of Candida parapsilosis Glu228Ser/(S)-carbonyl reductase II and Bacillus sp. YX-1 glucose dehydrogenase for efficient chiral synthesis in organic solvents. Results: The spore microencapsulation of E228S/SCR II and GDH in S. cerevisiae AN120 osw2Δ catalyzed (R)-phenylethanol in a good yield with an excellent enantioselectivity (up to 99%) within 4 h. It presented good resistance and catalytic functions under extreme temperature and pH conditions. The encapsulation produced several chiral products with over 70% yield and over 99% enantioselectivity in Et acetate after being recycled for 4-6 times. It increased substrate concentration over threefold and reduced the reaction time two to threefolds compared to the recombinant Escherichia coli containing E228S and glucose dehydrogenase. Conclusions: This work first described sustainable enantioselective synthesis without exogenous cofactors in organic solvents using yeast spore-microencapsulation of coupled alc. dehydrogenases.[Figure not available: see fulltext.]. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Electric Literature of 3976-69-0

The Article related to saccharomyces candida bacillus spore encapsulation carbonyl reductase gdh solvent, (s)-carbonyl reductase ii, glucose dehydrogenase, organic solvent, spore-microencapsulation, sustainable enantioselective catalysis and other aspects.Electric Literature of 3976-69-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

On September 13, 2017, Sargent, Brendon T.; Alexanian, Erik J. published an article.Recommanded Product: (R)-Methyl 3-hydroxybutanoate The title of the article was Cobalt-Catalyzed Carbonylative Cross-Coupling of Alkyl Tosylates and Dienes: Stereospecific Synthesis of Dienones at Low Pressure. And the article contained the following:

Nonracemic dienones such as I were prepared diastereoselectively and enantiospecifically in 38-82% yields and in 93:7-98.5:1.5 enantiospecificities by coupling of secondary alkyl tosylates such as II with 1,3-dienes such as (E)-PhCH:CHCH:CH2 in the presence of KCo(CO)4 and 2,2,6,6-tetramethylpiperidine in tert-amyl alc. under 2 atm. of CO pressure. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Recommanded Product: (R)-Methyl 3-hydroxybutanoate

The Article related to dienone nonracemic diastereoselective preparation, cobalt catalyst stereoselective carbonylation coupling secondary alkyl tosylate diene, enantiospecific carbonylative cross coupling secondary alkyl tosylate diene and other aspects.Recommanded Product: (R)-Methyl 3-hydroxybutanoate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

On September 7, 2012, Grove, Charles I.; Di Maso, Michael J.; Jaipuri, Firoz A.; Kim, Michelle B.; Shaw, Jared T. published an article.Safety of (R)-Methyl 3-hydroxybutanoate The title of the article was Synthesis of 6,6′-Binaphthopyran-2-one Natural Products: Pigmentosin A, Talaroderxines A and B. And the article contained the following:

Efficient and stereoselective syntheses of pigmentosin A I, talaroderxine A II, and its diastereomer talaroderxine B III are reported. The binaphthyl ring system is assembled by vanadium-catalyzed phenolic coupling of tricyclic precursors. These key intermediates were prepared by Michael-Dieckmann annulation of a protected orsellinate ester, with the requisite pyranones accessed by a new variant of Ghosez’s sulfone-epoxide annulation. Preliminary biol. experiments are reported for pigmentosin. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Safety of (R)-Methyl 3-hydroxybutanoate

The Article related to pigmentosin a stereoselective synthesis coupling vanadium catalyst, michael dieckmann annulation stereoselective synthesis pigmentosin a talaroderxine, talaroderxine a b stereoselective synthesis coupling vanadium catalyst and other aspects.Safety of (R)-Methyl 3-hydroxybutanoate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Bao, Deng-Hui; Wu, Hui-Ling; Liu, Chao-Lun; Xie, Jian-Hua; Zhou, Qi-Lin published an article in 2015, the title of the article was Development of Chiral Spiro P-N-S Ligands for Iridium-Catalyzed Asymmetric Hydrogenation of β-Alkyl-β-Ketoesters.Electric Literature of 3976-69-0 And the article contains the following content:

The chiral tridentate spiro P-N-S ligands, e.g., I, (SpiroSAP) were developed, and their iridium complexes were prepared Introduction of a 1,3-dithiane moiety into the ligand resulted in a highly efficient chiral iridium catalyst for asym. hydrogenation of β-alkyl-β-ketoesters, producing chiral β-alkyl-β-hydroxyesters, e.g., II, with excellent enantioselectivities (95-99.9 % ee) and turnover numbers of up to 355000. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Electric Literature of 3976-69-0

The Article related to tridentate spiro ligand preparation iridium complexation, enantioselective alkyl hydroxyester preparation, alkyl ketoester asym hydrogenation iridium catalyst, asymmetric catalysis, hydrogenation, iridium, ketoesters, spiro ligands and other aspects.Electric Literature of 3976-69-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

Seki, Tomohiro; McEleney, Kevin; Crudden, Cathleen M. published an article in 2012, the title of the article was Enantioselective catalysis with a chiral, phosphane-containing PMO material.Product Details of 3976-69-0 And the article contains the following content:

A novel bistriethoxysilyl-BINAP monomer was prepared and co-condensed with a biphenylene-bridged siloxane precursor in the presence of surfactant templates to give periodic mesoporous organosilicas (PMOs) functionalized with BINAP. Complexation of ruthenium followed by asym. catalytic hydrogenation and asym. transfer hydrogenation were carried out, and demonstrated that high levels of activity and selectivity are achievable with the chiral material. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Product Details of 3976-69-0

The Article related to mesoporous organosilica binap ruthenium preparation enantioselective catalyst, bistriethoxysilyl binap preparation condensation siloxane precursor, ruthenium mesoporous organosilica binap complex preparation asym transfer hydrogenation and other aspects.Product Details of 3976-69-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

On January 15, 2016, Xie, Sheng-Ming; Zhang, Jun-Hui; Fu, Nan; Wang, Bang-Jin; Chen, Ling; Yuan, Li-Ming published an article.Safety of (R)-Methyl 3-hydroxybutanoate The title of the article was A chiral porous organic cage for molecular recognition using gas chromatography. And the article contained the following:

Mol. organic cages as shape-persistent organic mols. with permanent and accessible cavities have attracted a lot of interest because of their importance as host-guest systems. Herein, the authors report a chiral porous organic cage (POC) CC9 diluted with a polysiloxane OV-1701 to fabricate a CC9-coated capillary column, which was used for the high-resolution gas chromatog. separation of organic compounds, including positional isomers and racemates. On the porous organic cage CC9-coated capillary column, a large number of racemic compounds such as chiral alcs., esters, ethers and epoxides can be resolved without derivatization. By comparing the chiral recognition ability of the CC9-coated column with the com. available β-DEX 120 column and the POC CC3-R coated column recently reported by the authors’ group, the CC9-coated column offered good resolution during the separation of some racemates, that were not separated using the β-DEX 120 column or POC CC3-R coated column. Therefore, the CC9-coated column can be complementary to the β-DEX 120 column and CC3-R coated column. The CC9-coated column exhibited great potential for application in the separation of positional isomers and enantiomers with great selectivity, high resolution and good reproducibility. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Safety of (R)-Methyl 3-hydroxybutanoate

The Article related to porous organic cage stationary phase gc positional isomer separation, chiral porous organic cage stationary phase gas chromatog enantioseparation, capillary column, chiral separation, chiral stationary phase, gas chromatography, porous organic cage and other aspects.Safety of (R)-Methyl 3-hydroxybutanoate

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

On June 30, 2022, Wu, Fan-lin; Hu, Yong-hao; Ji, Peng; Li, Chen-chen; He, Jian published an article.SDS of cas: 3976-69-0 The title of the article was Metabonomics study on the hepatoprotective effect mechanism of polysaccharides from different processed products of Angelica sinensis on layer chickens based on UPLC-Q/TOF-MS/MS, multivariate statistical analysis and conjoint analysis. And the article contained the following:

Chicken colibacillosis is one of the most severe diseases in the poultry industry. Ceftiofur sodium (CS) is often used to treat it in clin. practice and lipopolysaccharide (LPS) accumulates in the chicken ′s body. Previous exptl. studies found that CS combined with LPS could induce liver injury in layer chickens, and polysaccharides from charred Angelica sinensis(CASP) had a better hepatoprotective effect than polysaccharides from unprocessed Angelica sinensis(UASP). However, the intervention mechanism was unclear. Thus, UPLC-Q/TOF-MS/MS-based metabonomics and transcriptomics were used in this study to clarify the hepatoprotective effect mechanism of CASP and UASP in layer chickens. Transcriptomics and ELISA were used for biol. verification of some critical mutual metabolic pathways screened with metabonomics. The comprehensive anal. results showed that in a layer chicken liver injury model built with LPS and CS, 12 critical metabolic pathways were disturbed, involving 10 important differential metabolites. The hepatoprotective effect mechanism of CASP is related to the arachidonic acid metabolism and mTOR signaling pathways, involving nine important differential metabolites. In contrast, the hepatoprotective effect mechanism of UASP is related to the arachidonic acid metabolism pathway, involving six important differential metabolites. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).SDS of cas: 3976-69-0

The Article related to angelica sinensis polysaccharide hepatoprotective metabonomic multivariate statistical analysis, lps, layer chickens, liver injury, metabonomics, polysaccharides from charred angelica sinensis(casp), polysaccharides from unprocessed angelica sinensis(uasp) and other aspects.SDS of cas: 3976-69-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics

On April 9, 2014, Falkowski, Joseph M.; Sawano, Takahiro; Zhang, Teng; Tsun, Galen; Chen, Yuan; Lockard, Jenny V.; Lin, Wenbin published an article.Electric Literature of 3976-69-0 The title of the article was Privileged Phosphine-Based Metal-Organic Frameworks for Broad-Scope Asymmetric Catalysis. And the article contained the following:

A robust and porous Zr metal-organic framework (MOF) based on a BINAP-derived dicarboxylate linker, BINAP-MOF, was synthesized and post-synthetically metalated with Ru and Rh complexes to afford highly enantioselective catalysts for important organic transformations. The Rh-functionalized MOF is not only highly enantioselective (up to >99% ee) but also 3 times as active as the homogeneous control. XAFS studies revealed that the Ru-functionalized MOF contains Ru-BINAP precatalysts with the same coordination environment as the homogeneous Ru complex. The post-synthetically metalated BINAP-MOFs provide a versatile family of single-site solid catalysts for catalyzing a broad scope of asym. organic transformations, including addition of aryl and alkyl groups to α,β-unsaturated ketones and hydrogenation of substituted alkene and carbonyl compounds The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Electric Literature of 3976-69-0

The Article related to preparation ruthenium rhodium zirconium carboxyphenylethynyl binap hydroxo oxo framework, hydrogenation enantioselective catalyst ruthenium rhodium zirconium binap derivative framework, alkylation enantioselective catalyst ruthenium rhodium zirconium binap derivative framework and other aspects.Electric Literature of 3976-69-0

Referemce:
Ester – Wikipedia,
Ester – an overview | ScienceDirect Topics