Month: November 2022

Wuest, Frank R. published the artcile¹¹C-C bond formation by palladium-mediated cross-coupling of alkenylzirconocenes with [¹¹C]methyl iodide, Application of 3-Methylbut-2-en-1-yl benzoate, the publication is Journal of Labelled Compounds and Radiopharmaceuticals (2006), 49(2), 91-100, database is CAplus.

Hydrozirconation of substituted propynes followed by coupling with [¹¹C]methyl iodide was applied for preparation of methyl-group labeled alkenes. Reaction fo RCCMe with Cp₂ZrHCl with subsequent treatment with ¹¹C-Me iodide in the presence of Pd(PPh₃)₄ yielded the corresponding RCH:CMe(¹¹CH₃) (R = Ph, PhOCH₂, ^tBu, n-Pr, ^tBuMe₂SiOCH₂, HOCH₂, 4-NO₂C₆H₄OCH₂). The palladium complex Pd(PPh₃)₄ proved to be superior to Pt(PPh₃)₄ or Ni(PPh₃)₄ as transition metal complex. The scope and limitations of the novel palladium-mediated cross-coupling reaction of alkenylzirconocenes with [¹¹C]methyl iodide were tested with various internal alkynes. After heating at 60° for 6 min radiochem. yields of up to 75% (based upon [¹¹C]methyl iodide) could be achieved.

Journal of Labelled Compounds and Radiopharmaceuticals published new progress about 5205-11-8. 5205-11-8 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Benzene,Ester, name is 3-Methylbut-2-en-1-yl benzoate, and the molecular formula is C9H5ClO2, Application of 3-Methylbut-2-en-1-yl benzoate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Witzgall, P. published the artcileSex pheromone of grape berry moth (Lepidoptera: Tortricidae), Recommanded Product: (Z)-Dodec-9-en-1-yl acetate, the publication is Environmental Entomology (2000), 29(3), 433-436, database is CAplus.

Pheromone gland extracts of grape berry moth females, Endopiza viteana Clemens, contain the main pheromone component, Z9-12Ac, at ≈1.2 ng per female, together with both geometric isomers of 11-14Ac, and a number of saturated acetates and alcs. of the chain length 12-16. The analogous alc., Z9-12OH, was found in some gland extracts Trap capture of males was significantly increased by adding 0.5 or 2 μg of Z11-14Ac to 10 μg of the main compound, Z9-12Ac; whereas, adding 0.5 or 2 μg of E11-14Ac had no significant effect. In contrast, the addition of 5% Z9-12OH to the main compound resulted in a strong reduction in trap capture. Traps baited with a blend of Z9-12Ac and its geometric isomer, E9-12Ac, which was not detected in gland extracts, were significantly less attractive than traps baited with blends of Z9-12Ac and Z11-14Ac. Knowledge of pheromone components and antagonists is essential for development of the mating disruption technique. The compounds identified in E. viteana are behaviorally active in the three most important tortricid pests of grape, Vitis vinifera (L.), in Europe. It may thus be possible to use a single blend of synthetic pheromone for control of several species.

Environmental Entomology published new progress about 16974-11-1. 16974-11-1 belongs to esters-buliding-blocks, auxiliary class Aliphatic Chain, name is (Z)-Dodec-9-en-1-yl acetate, and the molecular formula is C7H10O4, Recommanded Product: (Z)-Dodec-9-en-1-yl acetate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Ferrara, Francesca published the artcileDimethyl Fumarate-Loaded Transethosomes: A Formulative Study and Preliminary Ex Vivo and In Vivo Evaluation., Application of Dimethyl fumarate, the publication is International journal of molecular sciences (2022), 23(15), database is MEDLINE.

In this study, transethosomes were investigated as potential delivery systems for dimethyl fumarate. A formulative study was performed investigating the effect of the composition of transethosomes on the morphology and size of vesicles, as well as drug entrapment capacity, using cryogenic transmission electron microscopy, photon correlation spectroscopy, and HPLC. The stability of vesicles was evaluated, both for size increase and capability to control the drug degradation. Drug release kinetics and permeability profiles were evaluated in vitro using Franz cells, associated with different synthetic membranes. The in vitro viability, as well as the capacity to improve wound healing, were evaluated in human keratinocytes. Transmission electron microscopy enabled the evaluation of transethosome uptake and intracellular fate. Based on the obtained results, a transethosome gel was further formulated for the cutaneous application of dimethyl fumarate, the safety of which was evaluated in vivo with a patch test. It was found that the phosphatidylcholine concentration affected vesicle size and lamellarity, influencing the capacity to control dimethyl fumarate’s chemical stability and release kinetics. Indeed, phosphatidylcholine 2.7% w/w led to multivesicular vesicles with 344 nm mean size, controlling the drug’s chemical stability for at least 90 days. Conversely, phosphatidylcholine 0.9% w/w resulted in 130 nm sized unilamellar vesicles, which maintained 55% of the drug over 3 months. These latest kinds of transethosomes were able to improve wound healing in vitro and were easily internalised by keratinocytes. The selected transethosome gel, loading 25 mg/mL dimethyl fumarate, was not irritant after cutaneous application under occlusion, suggesting its possible suitability in the treatment of wounds caused by diabetes mellitus or peripheral vascular diseases.

International journal of molecular sciences published new progress about 624-49-7. 624-49-7 belongs to esters-buliding-blocks, auxiliary class Inhibitor,Natural product, name is Dimethyl fumarate, and the molecular formula is C6H8O4, Application of Dimethyl fumarate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Bouvet, Vincent R. published the artcileA Short and Economical Synthesis of Orthogonally Protected C-Linked 2-Deoxy-2-acetamido-α-D-galactopyranose Derivatives, Recommanded Product: (3aR,5R,6R,7R,7aR)-5-(Acetoxymethyl)-2-methyl-5,6,7,7a-tetrahydro-3aH-pyrano[3,2-d]oxazole-6,7-diyl diacetate, the publication is Journal of Organic Chemistry (2006), 71(9), 3619-3622, database is CAplus and MEDLINE.

A short and high-yielding synthesis has been devised to prepare C-linked 2-deoxy-2-acetamido-α-D-galactopyranose derivative (I). One of the main advantages of this approach is that it employs com. available and inexpensive D-glucosamine as the starting material. The key steps include a highly stereoselective C-allylation followed by epimerization of the C-4 hydroxyl group. Building block I and orthogonally protected C-linked 2-deoxy-2-acetamido-α-D-galactopyranose derivative were obtained in 44% overall yield (six steps) and 29% overall yield (eight steps), resp. This represents a significant improvement over previously reported syntheses.

Journal of Organic Chemistry published new progress about 10378-06-0. 10378-06-0 belongs to esters-buliding-blocks, auxiliary class Other Aliphatic Heterocyclic,Chiral,Ester,Inhibitor,Inhibitor, name is (3aR,5R,6R,7R,7aR)-5-(Acetoxymethyl)-2-methyl-5,6,7,7a-tetrahydro-3aH-pyrano[3,2-d]oxazole-6,7-diyl diacetate, and the molecular formula is C14H19NO8, Recommanded Product: (3aR,5R,6R,7R,7aR)-5-(Acetoxymethyl)-2-methyl-5,6,7,7a-tetrahydro-3aH-pyrano[3,2-d]oxazole-6,7-diyl diacetate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Ammar, Samia published the artcileEssential oils from the halophytic plant Atriplex inflata F. Muell: chemical composition, antioxidant and antimicrobial activities, Category: esters-buliding-blocks, the publication is Journal of Medicinal and Aromatic Plant Sciences (2012), 34(3&4), 132-144, database is CAplus.

The present work was carried out to determine the chem. composition and to evaluate the antioxidant and the antimicrobial proprieties of the essential oil extracted from the different plant parts of Atriplex inflata F. Muell. In addition to essential oil, some organic extracts were also tested. Based on the GC/MS anal., difference in composition between leaves, fruits and roots was noticed. The antioxidant capacity of the volatile fractions and the organic extracts was determined by the inhibition of DPPH and ABTS⁺ radical forms. A pos. activity was observed in volatile fraction of leaves. Antimicrobial activity was evaluated by the determination of the minimal inhibition concentration (MIC) using the ethanolic and the acetonic extracts and the volatile fractions from fruits, leaves and roots. Bacteria and yeasts were found to be more sensitive towards volatile fraction extracted from the A. Inflata leaves.

Journal of Medicinal and Aromatic Plant Sciences published new progress about 16974-11-1. 16974-11-1 belongs to esters-buliding-blocks, auxiliary class Aliphatic Chain, name is (Z)-Dodec-9-en-1-yl acetate, and the molecular formula is C14H26O2, Category: esters-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Wang, Huamin published the artcileA base-controlled switch of SO₂ reincorporation in photocatalyzed radical difunctionalization of alkenes, Safety of Dimethyl itaconate, the publication is Chem (2021), 7(12), 3412-3424, database is CAplus.

Control of selectivity is a pivotal challenge in radical chem. owing to the high reactivity and instability of radical species. Herein, a switchable, base-controlled strategy toward the reincorporation/release of SO₂ in photocatalyzed radical difunctionalization of alkenes has been described. By this chemodivergent strategy, a variety of valuable, otherwise difficult-to-access γ-trifluoromethylated ketones and trifluoromethylated sulfonyl ketones can be selectively furnished from the same starting materials. This method features high chemoselectivity, a broad substrate scope, excellent functional group tolerance, and facile scale-up and was applied in a one-pot synthetic procedure. Evaluation of the reaction conditions and mechanistic studies indicate that the choice of base can invert the chemoselectivity of the reaction, demonstrating control over a challenging radical selectivity pattern.

Chem published new progress about 617-52-7. 617-52-7 belongs to esters-buliding-blocks, auxiliary class Alkenyl,Aliphatic hydrocarbon chain,Ester, name is Dimethyl itaconate, and the molecular formula is C18H24N6O6S4, Safety of Dimethyl itaconate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Fernandez-Blazquez, Juan P. published the artcileObservation of Two Glass Transitions in a Thermotropic Liquid-Crystalline Polymer, Category: esters-buliding-blocks, the publication is Macromolecules (2004), 37(24), 9018-9026, database is CAplus.

DSC and real-time variable-temperature synchrotron experiments have been performed on a thermotropic poly(ether-ester), PH31B32, with biphenyl units as mesogens and spacers with Me substituents. It has been found that PH31B32 develops a low-ordered SmCalt mesophase with a rather slow rate of formation in such a way that the isotropic melt of this polymer can be easily quenched into the glassy amorphous state at the usual cooling rates of the calorimeter. Considerably high annealing times at temperatures above T_g are necessary to develop such a mesophase. The extent of transformation and symmetry of the mesophase have been determined by means of calorimetric and X-ray diffraction experiments The DSC results show that the glass-transition temperatures of the amorphous and liquid-crystalline states are clearly different: 95 and 84 °C, resp. Moreover, the results show that the isotropization temperature increases linearly with the annealing temperature (the temperature at which the mesophase has been formed). The synchrotron experiments show that the mesophase layer spacing is slightly lower for the higher annealing temperatures, indicating a slightly more compact structure. Although the WAXS profiles of the two phases (mesophase and amorphous) are rather similar, the mesophase has noticeably smaller most probable intermol. distances and a smaller width of the WAXS broad peak. The temperature coefficients of these intermol. distances are also different for the various phases, and clear discontinuities are observed at the glass transitions. The corresponding values of T_g obtained from these results are 94 and 84 °C for the amorphous and liquid-crystalline phases, resp., in perfect agreement with the DSC results. The correlation lengths estimated from the widths of the mesophase layer peaks are of the order of the extended chain length of the polymer, so that no extensive chain folding seems to be present in the mesophase of PH31B32. This fact will favor the attainment of high degrees of liquid crystallinity. Moreover, the higher correlation lengths deduced for the higher annealing temperatures point to a segregation of defects from the smectic structure in a greater extent, which may explain the corresponding higher isotropization temperatures

Macromolecules published new progress about 50670-76-3. 50670-76-3 belongs to esters-buliding-blocks, auxiliary class Benzene,Phenol,Ester, name is Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate, and the molecular formula is C15H14O3, Category: esters-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

del Campo, Aranzazu published the artcileAmorphous-smectic glassy main-chain LCPs. 1. Poly(ether esters) derived from hydroxybibenzoic acid and (R,S)- and (R)-2-methylpropane-1,3-diol, Name: Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate, the publication is Macromolecular Chemistry and Physics (2002), 203(17), 2508-2515, database is CAplus.

The synthesis and the characterization of main-chain liquid-crystalline poly(ether esters), derived from hydroxybibenzoic acid and (R,S)- and (R)-2-methylpropane-1,3-diol, are reported. These polymers show an interesting thermal behavior. They develop mesophases with a slow rate of formation, allowing the easy quenching of the melt into: a) the glassy amorphous state, b) the glassy liquid-crystalline state, or c) a mixture of both, depending on the thermal treatment. The extent of the transformation and the symmetry of the different phases have been determined by means of calorimetric and X-ray diffraction methods. Dielec. spectroscopy results provide addnl. evidence for the detection of distinct glass transitions. The results show that the racemic polymer forms a low-ordered SmC_alt mesophase, while a more ordered phase is obtained in the case of the enantiomerically pure polymer. The comparison of the properties of the different states evidences the special behavior and properties of the glass transition (T_g) in these polymers. Emphasis is paid to the location of the T_g of the liquid-crystalline state in comparison to the T_g of the amorphous state. It is found that the glass transition of the SmC_alt glass in R,S-PBO3 (the poly(ether ester) derived from hydroxybibenzoic acid and (R,S)-2-methylpropane-1,3-diol) appears at lower temperatures than the glass transition of the amorphous state. However, in R-PBO3 (the poly(ether ester) derived from hydroxybibenzoic acid and (R)-2-methylpropane-1,3-diol), where the more ordered phase is present, the glass transition follows the classical tendency of semicrystalline polymers.

Macromolecular Chemistry and Physics published new progress about 50670-76-3. 50670-76-3 belongs to esters-buliding-blocks, auxiliary class Benzene,Phenol,Ester, name is Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate, and the molecular formula is C15H14O3, Name: Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Honglawan, Apiradee published the artcilePillar-Assisted Epitaxial Assembly of Toric Focal Conic Domains of Smectic-A Liquid Crystals, Product Details of C15H14O3, the publication is Advanced Materials (Weinheim, Germany) (2011), 23(46), 5519-5523, database is CAplus and MEDLINE.

The authors demonstrated epitaxial assembly of SmA LCs using top-down fabricated polymer pillar arrays. The 3-dimensional nature of the pillar array is crucial to confine and direct the formation of toric focal conic domains on the top of each pillar as well as between neighboring pillars. Independent of LC thickness (above a critical thickness hc), the pattern of SU-8 pillar arrays determined the final crystal habit of the toric focal conic domain array (TFCD): both highly ordered square and hexagonal array of TFCDs were obtained. The epitaxial approach presented here offers an entirely new and promising organizational principle for smectic LC systems using simple topog. substrates. In turn, it may give more complex LC phases in 3-dimensional that are critical to the advancement of LC-based electronic and optical devices,’25,26′ and perhaps generation of novel materials when incorporating functional units such as nanoparticles, nanocrystals, and carbon nanotubes into the LC layers.

Advanced Materials (Weinheim, Germany) published new progress about 50670-76-3. 50670-76-3 belongs to esters-buliding-blocks, auxiliary class Benzene,Phenol,Ester, name is Ethyl 4′-hydroxy-[1,1′-biphenyl]-4-carboxylate, and the molecular formula is C15H14O3, Product Details of C15H14O3.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics

Whittle, C. P. published the artcileThe sex pheromone and taxonomic status of Homona spargotis Meyrick sp. rev., an Australian pest species of the Coffearia group (Lepidoptera:Tortricidae:Torticinae), Category: esters-buliding-blocks, the publication is Journal of the Australian Entomological Society (1987), 26(2), 169-79, database is CAplus.

A tortricid pest of avocado in Australia, previously thought to be H. coffearia (Nietner), is shown by pheromone anal. and taxonomic re-examination to be a distinct species; the name Homona spargotis Meyrick is reinstated for it. Adults and genitalia of each sex are figured for both species. The genitalia of the true H. coffearia are illustrated apparently for the first time. Australia is now excluded from the known range of H. coffearia.

Journal of the Australian Entomological Society published new progress about 16974-11-1. 16974-11-1 belongs to esters-buliding-blocks, auxiliary class Aliphatic Chain, name is (Z)-Dodec-9-en-1-yl acetate, and the molecular formula is C17H19N3O6, Category: esters-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ester,
Ester – an overview | ScienceDirect Topics