Month: December 2022

Reuter, Hans published the artcileGuanosine nucleolipids: Synthesis, characterization, aggregation and X-Ray crystallographic identification of electricity-conducting G-ribbons, Safety of Ethyl 4-oxopentanoate, the main research area is glioblastoma cytotoxic guanosine nucleolipid synthesis aggregation crystallog; cytotoxic activity; drug profiling; glioblastoma; guanosine; nucleolipids; self-assembly; synthesis design.

The lipophilization of β-D-riboguanosine (1) with various sym. as well as asym. ketones is described (→3a-3f). The formation of the corresponding O-2′,3′-ketals is accompanied by the appearance of various fluorescent byproducts which were isolated chromatog. as mixtures and tentatively analyzed by ESI-MS spectrometry. The mainly formed guanosine nucleolipids were isolated and characterized by elemental analyses, 1H-, 13C-NMR and UV spectroscopy. For a drug profiling, static topol. polar surface areas as well as 10logPOW values were calculated by an increment-based method as well as exptl. for the systems 1-octanol-H2O and cyclohexane-H2O. The guanosine-O-2′,3′-ketal derivatives 3b and 3a could be crystallized in (D6)DMSO – the latter after one year of standing at ambient temperature X-ray anal. revealed the formation of self-assembled ribbons consisting of two structurally similar 3b nucleolipid conformers as well as integrated (D6)DMSO mols. In the case of 3a · DMSO, the ribbon is formed by a single type of guanosine nucleolipid mols. The crystalline material 3b · DMSO was further analyzed by differential scanning calorimetry (DSC) and temperature-dependent polarization microscopy. Crystallization was also performed on interdigitated electrodes (Au, distance, 5μm) and visualized by SEM. Resistance and amperage measurements clearly demonstrate that the electrode-bridging 3b crystals are elec. conducting. All O-2′,3′-guanosine ketals were tested on their cytostatic/cytotoxic activity towards phorbol 12-myristate 13-acetate (PMA)-differentiated human THP-1 macrophages as well as against human astrocytoma/oligodendroglioma GOS-3 cells and against rat malignant neuroectodermal BT4Ca cells.

Chemistry & Biodiversity published new progress about Aggregation. 539-88-8 belongs to class esters-buliding-blocks, name is Ethyl 4-oxopentanoate, and the molecular formula is C7H12O3, Safety of Ethyl 4-oxopentanoate.

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

Jangizehi, Amir published the artcileDynamics of supramolecular associative polymer networks at the interplay of chain entanglement, transient chain association, and chain-sticker clustering, Product Details of C16H30O2, the main research area is dynamic supramol associative polymer network interplay chain entanglement sticker.

The dynamic mech. properties of supramol. associative polymer networks depend on the average number of entanglements along the network-forming chains, Ne, and on their content of associative groups, f. In addition, there may be further influence by aggregation of the associative groups into clusters, which, in turn, is influenced by the chem. structure of these groups, and again by Ne and f of the polymer. Therefore, the effects of these parameters are interdependent. To conceptually understand this interdependency, we study model networks in which (a) Ne, (b) f, and (c) the chem. structure of the associative groups are varied systematically. Each network is probed by rheol. The clustering of the associative groups is assessed by analyzing the rheol. data at the end range of frequency covered and by comparison of the number of supramol. network junctions with the maximum possible number of binary transient bonds. We find that if the total number of the network junctions, which can be formed either by interchain entanglement or by interchain transient associations, is greater than a threshold of 13, then the likelihood of cluster formation is high and the dynamics of supramol. associative polymer networks is mainly controlled by this phenomenon. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019.

Journal of Polymer Science, Part B: Polymer Physics published new progress about Aggregation. 142-90-5 belongs to class esters-buliding-blocks, name is Dodecyl 2-methylacrylate, and the molecular formula is C16H30O2, Product Details of C16H30O2.

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

Kumar, Ravi published the artcileOxygen and Drug-Carrying Periodic Mesoporous Organosilicas for Enhanced Cell Viability under Normoxic and Hypoxic Conditions, Computed Properties of 2044-85-1, the main research area is melanoma hypoxia oxygen mesoporous organosilica cell viability; drug delivery; hybrid materials; nanostructured materials; oxygen-carrying materials.

Over the last decade, inorganic/organic hybrids have been exploited for oxygen-carrying materials and drug delivery. Its low-cost synthesis, controlled shape and size, and stability have made it a viable delivery strategy for therapeutic agents. Rutin (quercetin-3-O-rutinoside) is a bioflavonoid found in fruits and vegetables. Rutin has a variety of pharmaceutical applications, but its low water solubility reduces its stability and bioavailability. As a result, we introduce a new and stable nanosystem for loading a low-soluble drug (rutin) into oxygen-carrying periodic mesoporous organosilicas (PMO-PFCs). Over the course of 14 days, this nanosystem provided a sustained oxygen level to the cells in both normoxic and hypoxic conditions. At different pH values, the drug release (rutin) profile is also observed Furthermore, the rutin-coated PMO-PFCs interacted with both healthy and malignant cells. The healthy cells have better cell viability on the rutin-coated oxygen-carrying PMO-PFCs, while the malignant cells have a lower cell viability.

International Journal of Molecular Sciences published new progress about Aggregation. 2044-85-1 belongs to class esters-buliding-blocks, name is 2′,7′-Dichloro-3-oxo-3H-spiro[isobenzofuran-1,9′-xanthene]-3′,6′-diyl diacetate, and the molecular formula is C24H14Cl2O7, Computed Properties of 2044-85-1.

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

Li, Shan published the artcileProbiotic potential of γ-aminobutyric acid (GABA)-producing yeast and its influence on the quality of cheese, Computed Properties of 123-29-5, the main research area is yeast aminobutyric acid probiotic potential cheese quality; aroma; physical and chemical indicators; probiotic; yeast; γ-aminobutyric acid (GABA).

Kazakh cheese is a traditional dairy product in Xinjiang, China. To study the function and potential probiotic characteristics of yeast in Kazakh cheese and its contribution to cheese fermentation, we screened the γ-aminobutyric acid (GABA)-producing yeasts Pichia kudriavzevii 1-21, Kluyveromyces marxianus B13-5, Saccharomyces cerevisiae DL6-20, and Kluyveromyces lactis DY1-10. We investigated the potential probiotic properties of these strains and their use in cheese fermentation (cheeses designated CSP, CSM, CSS, and CSI, resp.); a control with no added yeast was designated CS. The results showed that the 4 yeast strains all showed high self-polymerization (2- and 24-h autoaggregation capacity of >80 and 90%, resp.), hydrophobicity (40-92% variation, low hydrophobicity in xylene, but within the range of probiotics), and the ability to survive the gastrointestinal tract (survival rate >75% after simulation), indicating the probiotic ability of the strains in vitro. The GABA production capacity of the CSM cheese increased (to 95.6 mg/100 g), but its protein content did not change significantly, and amino acid degradation was obvious. The GABA production capacity of the CSS cheese decreased (to 450 mg/kg); its protein content declined, and its amino acid content increased. Except for water and protein, we found no obvious differences in most phys. and chem. indicators. Kluyveromyces marxianus B13-5 helped to form the desired texture. Multivariate statistical anal. showed that fermentation of the cheese with the 4 yeasts improved the production of esters and alcs. The CSS cheese had good aroma production performance, because S. cerevisiae DL6-20 produced high concentrations of isoamyl alc., hexanoic acid Et ester, benzyl alc., octanoic acid Et ester, 3-hydroxy-2-butanone, and hexanoic acid; the content of 2-methyl-propanoic acid was low. Compared with the CSP cheese, the CSI and CSM cheeses had a fruitier aroma and a milder odor, but the CSI and CSM cheeses had high concentrations of Et acetate, butanoic acid, Et ester, 3-methyl-1-butanol-acetate, Et hexanoate, Et octanoate, acetic acid 2-phenylethyl ester, and Et lactate; concentrations of 3-methyl-butanoic acid, propanoic acid, acetic acid, and butanoic acid were low. The CSP cheese had stronger acid-producing ability. The order of fragrance production performance was CSS > CSI, CSM > CSP > CS. Research into the fermentation mechanisms of GABA-producing yeast in cheese will provide a theor. basis for the quality control and industrial production of Kazakh cheese.

Journal of Dairy Science published new progress about Aggregation. 123-29-5 belongs to class esters-buliding-blocks, name is Ethyl nonanoate, and the molecular formula is C11H22O2, Computed Properties of 123-29-5.

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

Ferreira, Victor H. C. published the artcileUse of color based chromatographic images obtained from comprehensive two-dimensional gas chromatography in authentication analyses, SDS of cas: 123-29-5, the main research area is color volatile organic compound two dimensional gas chromatog; Fingerprinting; Foodomics; Image processing; One-class classifiers; Solid-phase microextraction; Spirits.

Comprehensive two-dimensional gas chromatog. (GCxGC) has been an important technique used to acquire as much information as possible from a wide variety of samples. Qual. contour plots anal. provides useful information and in daily use it ends up being handled as images of the volatile organic compounds by analysts. Cachaca samples are used in this paper to showcase the use of two-dimensional chromatog. images as the main source for authentication purposes through one-class classifiers, such as data-driven soft independent modeling of class analogy (DD-SIMCA). The proposed workflow summarizes this fast and easy process, which can be used to certify a specific brand in comparison to other brands, as well as to authenticate if samples have been adulterated. Lower quality cachacas, non-aged cachacas and cachacas aged in different wooden barrels were tested as adulterants. Chromatog. images allowed for the distinction of all brands and nearly every adulteration tested. Sensitivity was estimated at 100% for all models and specificity ranged from 96% to 100%. Different approaches were used, alternating from working with whole-sized images to working with smaller resized versions of those images. Resized chromatog. images could be potentially useful to easily compensate for slight chromatog. misalignments, allowing for faster calculations and the use of simpler software. Reductions to 50% and 25% of the original size were tested and the results did not greatly differ from whole images model. As such, 2D chromatog. images have been found to be an interesting form of evaluating a product’s authenticity.

Talanta published new progress about Adulterants. 123-29-5 belongs to class esters-buliding-blocks, name is Ethyl nonanoate, and the molecular formula is C11H22O2, SDS of cas: 123-29-5.

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

Li, Lu published the artcileDecreasing the acid value of pyrolysis oil via esterification using ZrO2/SBA-15 as a solid acid catalyst, Name: Methyl octanoate, the main research area is zirconia silica solid acid catalyst oil esterification.

The high acid value of pyrolysis oil obtained from biol. oil is the main drawback that not only affects the properties of pyrolysis oil, but also leads to the corrosion of equipment. Herein, pyrolysis oil obtained from rubber seed oil was upgraded via esterification using ZrO2/SBA-15 as a solid acid catalyst. Using ZrO2/SBA-15 as a catalyst, the acid value of the esterified pyrolysis oil obtained from rubber seed oil was only 1.2 mg KOH·g-1. The d. and kinematic viscosity both reached the standard range of 0# diesel oil. The excellent catalytic activity of ZrO2/SBA-15 was studied using NH3-TPD and Py-IR. Furthermore, the conversion reached 96.7% when the ZrO2/SBA-15 catalyst was re-used three times, which shows the ZrO2/SBA-15 catalyst possessed excellent catalytic activity and stability for upgrading pyrolysis oil via esterification.

Renewable Energy published new progress about Acid number. 111-11-5 belongs to class esters-buliding-blocks, name is Methyl octanoate, and the molecular formula is C9H18O2, Name: Methyl octanoate.

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

Li, Lu published the artcileDecreasing the acid value of pyrolysis oil via esterification using ZrO2/SBA-15 as a solid acid catalyst, HPLC of Formula: 110-42-9, the main research area is zirconia silica solid acid catalyst oil esterification.

The high acid value of pyrolysis oil obtained from biol. oil is the main drawback that not only affects the properties of pyrolysis oil, but also leads to the corrosion of equipment. Herein, pyrolysis oil obtained from rubber seed oil was upgraded via esterification using ZrO2/SBA-15 as a solid acid catalyst. Using ZrO2/SBA-15 as a catalyst, the acid value of the esterified pyrolysis oil obtained from rubber seed oil was only 1.2 mg KOH·g-1. The d. and kinematic viscosity both reached the standard range of 0# diesel oil. The excellent catalytic activity of ZrO2/SBA-15 was studied using NH3-TPD and Py-IR. Furthermore, the conversion reached 96.7% when the ZrO2/SBA-15 catalyst was re-used three times, which shows the ZrO2/SBA-15 catalyst possessed excellent catalytic activity and stability for upgrading pyrolysis oil via esterification.

Renewable Energy published new progress about Acid number. 110-42-9 belongs to class esters-buliding-blocks, name is Methyl decanoate, and the molecular formula is C11H22O2, HPLC of Formula: 110-42-9.

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

Xiao, Mengshi published the artcileSynthesis of Biodiesel from Waste Cooking Oil by One-step Esterification and Its Structural Characterization, COA of Formula: C23H46O2, the main research area is waste cooking oil biodiesel esterification.

The preparation of biodiesel as an alternative to petroleum-based fuels can expand the research and development of renewable energy, and is conducive to environmental protection. In this study, waste cooking oil (WCO) was used as raw material, and then pretreated, and then esterified with methanol under the action of sodium hydroxide catalyst to transformed into fatty acid Me ester (FAME) to prepare biodiesel. The reaction conditions were optimized by a three factorial Box-Behnken design through response surface methodol., when the reaction temperature was 70.1°C, the catalyst concentration was 1.013% and the molar ratio of methanol to oil was 6.5:1, the maximum FAME was up to 99.342%. Finally, the conversion of the triglyceride to the Me ester was confirmed by NMR (1H and 13C), and no unsaturation was present in the Me ester. The chem. composition of biodiesel was determined by GC-MS anal. There are mainly 11 FAME ranging from C16 to C24. The potential of WCO to prepare biodiesel was obtained.

Waste and Biomass Valorization published new progress about Acid number. 929-77-1 belongs to class esters-buliding-blocks, name is Methyl docosanoate, and the molecular formula is C23H46O2, COA of Formula: C23H46O2.

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

Marso, Tuan Mohommed Mudassar published the artcileZnO/CuO composite catalyst to pre-esterify waste coconut oil for producing biodiesel in high yield, Safety of Methyl octanoate, the main research area is zinc copper oxide composite catalyst waste coconut oil biodiesel.

The study reported herein describes a two-stepped catalytic approach to produce biodiesel from waste-coconut oil in high (> 90%) yield. In this regard, pre-esterification of the Free Fatty Acid (FFA) content (9.58 mg KOH g-1) of waste coconut oil in the presence of a simple ZnO/CuO composite, as a heterogeneous acid-catalyst to prevent competitive saponification and hydrolysis side reactions caused by FFA, followed by the base-catalyzed transesterification of the triglyceride of oil was performed. The ZnO/CuO catalyst was synthesized using a simultaneous precipitation method, and characterized by spectroscopic (FTIR, UV-Vis), SEM, XRD and XRF techniques. The surface acidity of the catalyst and the FFA value (AV) of the oil before and after the pre-esterification was determined using the Hammett indicator method. The pre-esterification was performed at different temperatures (5-125°C), time intervals (15-235 min), and using different weight percentages (wt%) of catalyst loading (0.005-2.665) and methanol-to-oil ratios. The optimum reaction conditions were identified using a central composite rotatable design (CCRD). The results of the study revealed that a small amount of the catalyst (1.66 wt%) is enough, and the catalyst could be easily recovered and reused 3-4 catalytic runs for reducing the AV of waste coconut oil by 94.53% under milder conditions (within 113 min, at 55°C in the presence of 10.5:1 methanol-to-oil ratio) than those conditions reported so far. The biodiesel obtained this way was free from soap, and consistent with ASTM-D6751 and EN-14214 standards

Reaction Kinetics, Mechanisms and Catalysis published new progress about Acid number. 111-11-5 belongs to class esters-buliding-blocks, name is Methyl octanoate, and the molecular formula is C9H18O2, Safety of Methyl octanoate.

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

Marso, Tuan Mohommed Mudassar published the artcileZnO/CuO composite catalyst to pre-esterify waste coconut oil for producing biodiesel in high yield, Synthetic Route of 110-42-9, the main research area is zinc copper oxide composite catalyst waste coconut oil biodiesel.

The study reported herein describes a two-stepped catalytic approach to produce biodiesel from waste-coconut oil in high (> 90%) yield. In this regard, pre-esterification of the Free Fatty Acid (FFA) content (9.58 mg KOH g-1) of waste coconut oil in the presence of a simple ZnO/CuO composite, as a heterogeneous acid-catalyst to prevent competitive saponification and hydrolysis side reactions caused by FFA, followed by the base-catalyzed transesterification of the triglyceride of oil was performed. The ZnO/CuO catalyst was synthesized using a simultaneous precipitation method, and characterized by spectroscopic (FTIR, UV-Vis), SEM, XRD and XRF techniques. The surface acidity of the catalyst and the FFA value (AV) of the oil before and after the pre-esterification was determined using the Hammett indicator method. The pre-esterification was performed at different temperatures (5-125°C), time intervals (15-235 min), and using different weight percentages (wt%) of catalyst loading (0.005-2.665) and methanol-to-oil ratios. The optimum reaction conditions were identified using a central composite rotatable design (CCRD). The results of the study revealed that a small amount of the catalyst (1.66 wt%) is enough, and the catalyst could be easily recovered and reused 3-4 catalytic runs for reducing the AV of waste coconut oil by 94.53% under milder conditions (within 113 min, at 55°C in the presence of 10.5:1 methanol-to-oil ratio) than those conditions reported so far. The biodiesel obtained this way was free from soap, and consistent with ASTM-D6751 and EN-14214 standards

Reaction Kinetics, Mechanisms and Catalysis published new progress about Acid number. 110-42-9 belongs to class esters-buliding-blocks, name is Methyl decanoate, and the molecular formula is C11H22O2, Synthetic Route of 110-42-9.

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