Category: 3976-69-0

Siedler, Solvej; Lindner, Steffen N.; Bringer, Stephanie; Wendisch, Volker F.; Bott, Michael published an article in 2013, the title of the article was Reductive whole-cell biotransformation with Corynebacterium glutamicum: improvement of NADPH generation from glucose by a cyclized pentose phosphate pathway using pfkA and gapA deletion mutants.Related Products of 3976-69-0 And the article contains the following content:

In this study, the potential of Corynebacterium glutamicum for reductive whole-cell biotransformation is shown. The NADPH-dependent reduction of the prochiral Me acetoacetate (MAA) to the chiral (R)-Me 3-hydroxybutyrate (MHB) by an alc. dehydrogenase from Lactobacillus brevis (Lbadh) was used as model reaction and glucose served as substrate for the regeneration of NADPH. Since NADPH is mainly formed in the oxidative branch of the pentose phosphate pathway (PPP), C. glutamicum was engineered to redirect carbon flux towards the PPP. Mutants lacking the genes for 6-phosphofructokinase (pfkA) or glyceraldehyde 3-phosphate dehydrogenase (gapA) were constructed and analyzed with respect to growth, enzyme activities, and biotransformation performance. Both mutants showed strong growth defects in glucose minimal medium. For biotransformation of MAA to MHB using glucose as reductant, strains were transformed with an Lbadh expression plasmid. The wild type showed a specific MHB production rate of 3.1 mmolMHB h-1 g and a yield of 2.7 molMHB mol. The ΔpfkA mutant showed a similar MHB production rate, but reached a yield of 4.8 molMHB mol, approaching the maximal value of 6 molNADPH mol expected for a partially cyclized PPP. The specific biotransformation rate of the ΔgapA mutant was decreased by 62 % compared to the other strains, but the yield was increased to 7.9 molMHB mol, which to our knowledge is the highest one reported so far for this mode of NADPH regeneration. As one fourth of the glucose was converted to glycerol, the exptl. yield was close to the theor. maximal yield of 9 molNADPH mol. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Related Products of 3976-69-0

The Article related to corynebacterium nadph generation reductive biotransformation pfka gapa deletion, Fermentation and Bioindustrial Chemistry: Industrial Chemicals and other aspects.Related Products of 3976-69-0

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

On September 15, 2012, Reis, Joel S.; Andrade, Leandro H. published an article.Name: (R)-Methyl 3-hydroxybutanoate The title of the article was Lipase-catalyzed kinetic resolution of β-borylated carboxylic esters. And the article contained the following:

The kinetic resolution of chiral β-borylated carboxylic esters via lipase-catalyzed hydrolysis and transesterification reactions was studied. The enantioselective hydrolysis catalyzed by CAL-B furnished the β-borylated carboxylic acid with reasonable enantiomeric excess (62% ee), while both Me and Et β-borylated carboxylic esters were recovered with excellent ee (>99%). Meanwhile, the transesterification reaction of β-borylated carboxylic esters and several alcs., catalyzed by CAL-B, only indicated a high selectivity when ethanol and methyl-(β-pinacolylboronate)-butanoate were used as substrates, which gave ethyl-(β-pinacolylboronate)-butanoate with >99% ee. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Name: (R)-Methyl 3-hydroxybutanoate

The Article related to kinetic resolution lipase catalyzed beta borylated carboxylic esters preparation, Organometallic and Organometalloidal Compounds: Boron Compounds and other aspects.Name: (R)-Methyl 3-hydroxybutanoate

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Ester – an overview | ScienceDirect Topics

Liu, Tao; Shen, Zhiqiang; Zhang, Chunyu; Song, Yudong; Li, Jie; Yang, Zongpu; Song, Guangqing; Han, Zhenfeng; Zhou, Yuexi published an article in 2019, the title of the article was Effect of influent pH on hydrolytic acidification performance and bacterial community structure in EGSB for pretreating crotonaldehyde manufacture wastewater after ozonation.Quality Control of (R)-Methyl 3-hydroxybutanoate And the article contains the following content:

The objective of this work was to evaluate the effect of influent pH on the hydrolytic acidification (HA) performance and microbial community structure in an expanded granular sludge bed (EGSB) pretreating crotonaldehyde manufacture wastewater (CMW) after ozonation. The results showed that higher COD (COD) removal rate (40.1%) and acidification degree (27.6%) were obtained at pH 8.0 than those at pH 6.0 and pH 4.0. The concentration of extractable extracellular polymeric substance (EPS) in the sludge gradually decreased with the pH decreasing from 8.0 to 4.0. A similar change was also observed for the concentration of total volatile fatty acids (TVFA) in the effluent. The optimal detoxification efficiency by the HA process was obtained at pH 8.0, with higher removal efficiency (all higher than 90%) of the main toxic pollutants (crotonaldehyde, 5-formyl-6-methyl-4,5-dihydropyran, etc.) and higher anaerobic biodegradation rate (44.5%) in biochem. methane potential (BMP) assay. Among the predominant genera, the Acinetobacter and Pseudomonas were possibly related to biodegradation of pollutants, since their higher relative abundance also coincided with the better performance of the HA process at pH 8.0. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Quality Control of (R)-Methyl 3-hydroxybutanoate

The Article related to hydrolytic acidification ph bacterial community crotonaldehyde ozonation wastewater, Waste Treatment and Disposal: Physical Treatment Of Aqueous Wastes and other aspects.Quality Control of (R)-Methyl 3-hydroxybutanoate

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

Sugimura, Takashi; Nakagawa, Satoshi; Kamata, Naoya; Tei, Takahiro; Tajiri, Takashi; Tsukiyama, Ryo-ichi; Okuyama, Tadashi; Okamoto, Yasuaki published an article in 2015, the title of the article was Ligand-acceleration by a chiral modifier in the enantioselective hydrogenation of methyl acetoacetate on a Raney nickel catalyst: effect of a modifier configuration.Quality Control of (R)-Methyl 3-hydroxybutanoate And the article contains the following content:

Reaction rate and enantioselectivity of asym. hydrogenation of Me acetoacetate were studied over Raneynickel catalysts modified with (R,R)-tartaric acid, malic acid, or succinic acid to reveal the impacts of the modifier configuration. Catalysts comodified with two different acids were also examined to confirm the conclusions. From anal. of the enantiomer ratio of the hydrogenation product and initial reaction rate, tartaric acid (TA) was found to have dual functions as the modifier during the hydrogenation; effective suppression of the racemic catalysis on bare Ni surface and extensive enantiodifferentiating ligand acceleration by adsorbed TA. It was demonstrated that each adsorbed chiral modifier mol. independently takes part in the enantiospecific hydrogenation. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Quality Control of (R)-Methyl 3-hydroxybutanoate

The Article related to methyl acetoacetate enantioselective hydrogenation raney nickel chiral ligand configuration, Physical Organic Chemistry: Other Reactions, Processes, and Spectra and other aspects.Quality Control of (R)-Methyl 3-hydroxybutanoate

Referemce:
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Ester – an overview | ScienceDirect Topics

On July 20, 2016, Wei, Ping; Gao, Jia-Xin; Zheng, Gao-Wei; Wu, Hong; Zong, Min-Hua; Lou, Wen-Yong published an article.HPLC of Formula: 3976-69-0 The title of the article was Engineering of a novel carbonyl reductase with coenzyme regeneration in E. coli for efficient biosynthesis of enantiopure chiral alcohols. And the article contained the following:

The novel anti-Prelog stereospecific carbonyl reductase from Acetobacter sp. CCTCC M209061 was successfully expressed in E. coli combined with glucose dehydrogenase (GDH) to construct an efficient whole-cell biocatalyst with coenzyme NADH regeneration. The enzymic activity of GAcCR (AcCR with a GST tag) reached 304.9 U/g-dcw, even 9 folds higher than that of wild strain, and the activity of GDH for NADH regeneration recorded 46.0 U/mg-protein in the recombinant E. coli. As a whole-cell biocatalyst, the recombinant E. coli BL21(DE3)pLysS (pETDuet-gaccr-gdh) possessed a broad substrate spectrum for kinds of carbonyl compounds with encouraging yield and stereoselectivity. Besides, the asym. reduction of Et 4-chloroacetoacetate (COBE) to optically pure Et 4-chloro-3-hydroxybutyrate (CHBE) catalyzed by the whole-cell biocatalyst was systematically investigated. Under the optimal reaction conditions, the optical purity of CHBE was over 99% e.e. for (S)-enantiomer, and the initial rate and product yield reached 8.04 μmol/min and 99.4%, resp. Moreover, the space-time yield was almost 20 folds higher than that catalyzed by the wild strain. Therefore, a new, high efficiency biocatalyst for asym. reductions was constructed successfully, and the enantioselective reduction of prochiral compounds using the biocatalyst was a promising approach for obtaining enantiopure chiral alcs. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).HPLC of Formula: 3976-69-0

The Article related to carbonyl reductase biosynthesis enantiopure chiral alc, (s)-chbe, acetobacter sp, asymmetric reduction, chiral alcohols, gaccr, whole-cell biocatalysis, Fermentation and Bioindustrial Chemistry: Methods (Including Analysis) and other aspects.HPLC of Formula: 3976-69-0

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

Dong, Xiang; Robinson, Jerome R. published an article in 2020, the title of the article was The role of neutral donor ligands in the isoselective ring-opening polymerization of rac-β-butyrolactone.HPLC of Formula: 3976-69-0 And the article contains the following content:

Isoenriched poly-3-hydroxybutyrate (P3HB) is a biodegradable material with properties similar to isotactic polypropylene, yet efficient routes to this material are lacking after 50+ years of extensive efforts in catalyst design. In this contribution, a novel lanthanum aminobisphenolate catalyst (1-La) can access isoenriched P3HB through the stereospecific ring-opening polymerization (ROP) of rac-β-butyrolactone (rac-BBL). Replacing the tethered donor group of a privileged supporting ligand with a non-coordinating benzyl substituent generates a catalyst whose reactivity and selectivity can be tuned with inexpensive achiral neutral donor ligands (e.g. phosphine oxides, OPR3). The 1-La/OPR3 (R = n-octyl, Ph) systems display high activity and are the most isoselective homogeneous catalysts for the ROP of rac-BBL to date (0°C: Pm = 0.8, TOF ~190 h-1). Combined reactivity and spectroscopic studies provide insight into the active catalyst structure and ROP mechanism. Both 1-La(TPPO)2 and a structurally related catalyst with a tethered donor group (2-Y) operate under chain-end stereocontrol; however, 2-RE favors formation of P3HB with opposite tacticity (syndioenriched) and its ROP activity and selectivity are totally unaffected by added neutral donor ligands. Our studies uncover new roles for neutral donor ligands in stereospecific ROP, including suppression of chain-scission events, and point to new opportunities for catalyst design. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).HPLC of Formula: 3976-69-0

The Article related to butyrolactone ring opening polymerization lanthanum aminobisphenolate catalyst, Chemistry of Synthetic High Polymers: Ring-Opening and Other Polymerizations and other aspects.HPLC of Formula: 3976-69-0

Referemce:
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Ester – an overview | ScienceDirect Topics

On June 13, 2022, Puentener, Kurt; Bigler, Raphael; Stier, Kenta; Checinski, Marek P. published an article.Related Products of 3976-69-0 The title of the article was New Mechanistic Insights into the Ru-Catalyzed Asymmetric Hydrogenation of β-Ketoesters. And the article contained the following:

We describe the results of our quantum mech. investigation of the asym. hydrogenation of β-ketoesters catalyzed by [RuCl2(MeOH)2((R)-MeOBIPHEP)] (7a), which is generated in situ from [Ru(OAc)2((R)-MeOBIPHEP)] (4a) and HCl in methanol. Interestingly, HCl not only acts as an activator for 4 a as it has a dramatic effect on the reaction itself: While HCl/4 a=2 leads to rather poor results (36% ee and 13% conv. after 4 h at at a substrate-to-catalyst ratio (S/C)=50’000), HCl/4 a=20 results in high efficiency (>99.9% conv.) and enantioselectivity (99% ee favoring the opposite enantiomer) under otherwise identical conditions. The origin for this sweeping change in performance has remained a mystery for two decades. Here, we show for the first time that a highly selective HCl pathway becomes operational under acidic conditions, which outcompetes moderately selective pathways dominating under neutral conditions. Furthermore, we explain the effects of common phosphorus substituents on the activity of the catalyst. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Related Products of 3976-69-0

The Article related to ketoester ruthenium catalyst stereoselective hydrogenation mechanism, Physical Organic Chemistry: Addition, Elimination, and Substitution Reactions and other aspects.Related Products of 3976-69-0

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

Cui, Y. H.; Wei, P.; Peng, F.; Zong, M. H.; Lou, W. Y. published an article in 2018, the title of the article was Efficient biocatalytic stereoselective reduction of methyl acetoacetate catalyzed by whole cells of engineered E. coli.Application In Synthesis of (R)-Methyl 3-hydroxybutanoate And the article contains the following content:

Asym. synthesis of chiral β-hydroxy esters, the key building blocks for many functional materials, is currently of great interest. In this study, the biocatalytic anti-Prelog reduction of Me acetoacetate (MAA) to methyl-(R)-3-hydroxybutyrate ((R)-HBME) was successfully carried out with high enantioselectivity using the whole cell of engineered E. coli, which harbored an AcCR (carbonyl reductase) gene from Acetobacter sp. CCTCC M209061 and a GDH (glucose dehydrogenase) gene from Bacillus subtilis 168 for the in situ regeneration of the coenzyme. Compared with the corresponding wild strain, the engineered E. coli cells were proved to be more effective for the bio-reduction of MAA, and afforded much higher productivity. Under the optimized conditions, the product e.e. was >99.9% and the maximum yield was 85.3% after a reaction time of 10 h, which were much higher than those reported previously. In addition, the production of (R)-HBME increased significantly by using a fed-batch strategy of tuning pH, with a space-time yield of approx. 265 g L-1 d-1, thus the issue in previous research of relatively low substrate concentrations appears to be solved. Besides, the established bio-catalytic system was proved to be feasible up to a 150 mL scale with a large-scale relatively high substrate concentration and selectivity. For further industrial application, these results open a way to use of whole cells of engineered E. coli for challenging higher substrate concentrations of β-ketone esters enantioselective reduction reactions. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Application In Synthesis of (R)-Methyl 3-hydroxybutanoate

The Article related to methyl acetoacetate escherichia coli, Fermentation and Bioindustrial Chemistry: Pharmaceuticals (Including Nutrients) and other aspects.Application In Synthesis of (R)-Methyl 3-hydroxybutanoate

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

Yang, Zeyu; Fu, Hengwei; Ye, Wenjie; Xie, Youyu; Liu, Qinghai; Wang, Hualei; Wei, Dongzhi published an article in 2020, the title of the article was Efficient asymmetric synthesis of chiral alcohols using high 2-propanol tolerance alcohol dehydrogenase SmADH2 via an environmentally friendly TBCR system.Quality Control of (R)-Methyl 3-hydroxybutanoate And the article contains the following content:

Alc. dehydrogenases (ADHs) together with the economical substrate-coupled cofactor regeneration system play a pivotal role in the asym. synthesis of chiral alcs.; however, severe challenges concerning the poor tolerance of enzymes to 2-propanol and the adverse effects of the byproduct, acetone, limit its applications, causing this strategy to lapse. Herein, a novel ADH gene smadh2 was identified from Stenotrophomonas maltophilia by traditional genome mining technol. The gene was cloned into Escherichia coli cells and then expressed to yield SmADH2. SmADH2 has a broad substrate spectrum and exhibits excellent tolerance and superb activity to 2-propanol even at 10.5 M (80%, volume/volume) concentration Moreover, a new thermostatic bubble column reactor (TBCR) system is successfully designed to alleviate the inhibition of the byproduct acetone by gas flow and continuously supplement 2-propanol. The organic waste can be simultaneously recovered for the purpose of green synthesis. In the sustainable system, structurally diverse chiral alcs. are synthesized at a high substrate loading (>150 g L-1) without adding external coenzymes. Among these, about 780 g L-1 (6 M) Et acetoacetate is completely converted into Et (R)-3-hydroxybutyrate in only 2.5 h with 99.9% ee and 7488 g L-1 d-1 space-time yield. Mol. dynamics simulation results shed light on the high catalytic activity toward the substrate. Therefore, the high 2-propanol tolerance SmADH2 with the TBCR system proves to be a potent biocatalytic strategy for the synthesis of chiral alcs. on an industrial scale. The experimental process involved the reaction of (R)-Methyl 3-hydroxybutanoate(cas: 3976-69-0).Quality Control of (R)-Methyl 3-hydroxybutanoate

The Article related to asym synthesis chiral alc propanol oxidation alc dehydrogenase, thermostatic bubble column reactor system alc dehydrogenase ketone reduction, Fermentation and Bioindustrial Chemistry: Pharmaceuticals (Including Nutrients) and other aspects.Quality Control of (R)-Methyl 3-hydroxybutanoate

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

On August 4, 2017, Makrerougras, Mehdi; Coffinier, Romain; Oger, Samuel; Chevalier, Arnaud; Sabot, Cyrille; Franck, Xavier published an article.SDS of cas: 3976-69-0 The title of the article was Total Synthesis and Structural Revision of Chaetoviridins A. And the article contained the following:

The first synthesis of the proposed structures of chaetoviridins A has been achieved in 10 steps by controlling the syn- or anti-aldol side chain. The angular lactone has been regioselectively introduced by condensation of a chiral dioxin-4-one to cazisochromene. Comparison of the NMR and CD data of the synthesized and reported natural products led to the complete reassignment of chaetoviridin A to I and renaming of the chaetoviridins. 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 chaetoviridin a synthesis absolute configuration revision, Biomolecules and Their Synthetic Analogs: Other Bacterial and Fungal Metabolites and other aspects.SDS of cas: 3976-69-0

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