Month: December 2022

Becker, Hinnerk Gordon published the artcileIntroduction of cyclic amidines into nitrile-containing polymers in the melt, Name: Propane-1,3-diamine dihydrochloride, the publication is Chemie Ingenieur Technik (2003), 75(1-2), 108-112, database is CAplus.

The reaction of nitrile-containing polymers (such as SAN) with diamines using ZnCl₂ and DBTO as catalysts to give cyclic amidines in the melt was studied as a function of several reaction parameters.

Chemie Ingenieur Technik published new progress about 10517-44-9. 10517-44-9 belongs to catalysis-chemistry, auxiliary class Salt,Amine,Aliphatic hydrocarbon chain, name is Propane-1,3-diamine dihydrochloride, and the molecular formula is C3H12Cl2N2, Name: Propane-1,3-diamine dihydrochloride.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Ursu, Andrei published the artcileSelective Host-Guest Binding of Anions without Auxiliary Hydrogen Bonds: Entropy as an Aid to Design, SDS of cas: 17351-61-0, the publication is Angewandte Chemie, International Edition (2012), 51(1), 242-246, database is CAplus and MEDLINE.

In contrast to classic host-guest design, which employs dedicated enthalpic interactions of the binding partners, a novel electroneutral host (I) has been prepared that binds its anionic guests by virtue of an overwhelmingly pos. entropy of association The prime driving force is guest desolvation. Despite the total omission of hydrogen bonding, host I is one of the best electroneutral receptors known for binding anions in polar solution

Angewandte Chemie, International Edition published new progress about 17351-61-0. 17351-61-0 belongs to catalysis-chemistry, auxiliary class Phase Transfer Catalyst, name is Tetraethylammonium hydrogencarbonate, and the molecular formula is C7H9BN2O3, SDS of cas: 17351-61-0.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Wuensch, Christiane published the artcilePushing the equilibrium of regio-complementary carboxylation of phenols and hydroxystyrene derivatives, HPLC of Formula: 17351-61-0, the publication is Journal of Biotechnology (2013), 168(3), 264-270, database is CAplus and MEDLINE.

The enzymic carboxylation of electron-rich aromatics, which represents a promising ‘green’ equivalent to the chem. Kolbe-Schmitt reaction, is thermodynamically disfavored and is therefore impeded by incomplete conversions. Optimization of the reaction conditions, such as pH, temperature, substrate concentration and the use of organic co-solvents and/or ionic liquids allowed to push the conversion in favor of carboxylation by a factor of up to 50%. Careful selection of the type of bicarbonate salt used as CO₂ source was crucial to ensure optimal activities. Among two types of carboxylases tested with their natural substrates, benzoic acid decarboxylase from Rhizobium sp. proved to be significantly more stable than phenolic acid decarboxylase from Mycobacterium colombiense; it tolerated reaction temperatures of up to 50 ¡ãC and substrate concentrations of up to 100 mM and allowed efficient biocatalyst recycling.

Journal of Biotechnology published new progress about 17351-61-0. 17351-61-0 belongs to catalysis-chemistry, auxiliary class Phase Transfer Catalyst, name is Tetraethylammonium hydrogencarbonate, and the molecular formula is C7H10O4, HPLC of Formula: 17351-61-0.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Tacke, Reinhold published the artcileSyntheses and Pharmacological Properties of the Histaminic H₁ Antagonists Sila-terfenadine-A, Sila-terfenadine-B, Disila-terfenadine, and Sila-fexofenadine: A Study on C/Si Bioisosterism, Formula: C12H10F2Si, the publication is Organometallics (2004), 23(21), 4915-4923, database is CAplus.

Sila-substitution (C/Si exchange) of one or both of the two quaternary carbon atoms of the histaminic H₁ antagonist terfenadine (1a) leads to sila-terfenadine-A (1b; R₃COH ¡ú R₃SiOH), sila-terfenadine-B (1c; R₄C ¡ú R₄Si), or disila-terfenadine (1d; R₃COH ¡ú R₃SiOH, R₄C ¡ú R₄Si). Sila-substitution of the quaternary carbon atom of the histaminic H₁ antagonist fexofenadine (2a) affords sila-fexofenadine (2b; R₃COH ¡ú R₃SiOH). The silicon compounds were synthesized in multistep syntheses, and the identities of these compounds and their precursors were established by elemental analyses and multinuclear NMR studies. Some of the precursors were addnl. characterized by single-crystal x-ray diffraction. The pharmacol. profiles of silicon compounds were assessed across a range of histaminic receptor binding assays (radioligand binding studies at histamine central H₁, peripheral H₁, H₂, and H₃ receptors). The silicon compounds, within exptl. error, exhibited an affinity and selectivity profile similar to their corresponding carbon analogs.

Organometallics published new progress about 312-40-3. 312-40-3 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Difluorodiphenylsilane, and the molecular formula is C3H6F3N, Formula: C12H10F2Si.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Svoboda, Jiri published the artcileThiourea-enhanced flavin photooxidation of benzyl alcohol, Safety of 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecan-1-amine, the publication is Chemistry – A European Journal (2008), 14(6), 1854-1865, database is CAplus and MEDLINE.

Upon irradiation, flavin oxidizes 4-methoxybenzyl alc. to the corresponding aldehyde using aerial O₂ as the terminal oxidant. We have observed that this reaction is significantly accelerated by the presence of thiourea. A series of thiourea-functionalized flavins has been prepared from flavin isothiocyanates and their photocatalytic efficiencies have been monitored by NMR. The alc. photooxidation proceeds rapidly and cleanly with high turnover numbers of up to 580, exceeding previously reported performances. A likely mechanistic rationale for the more than 30-fold acceleration of the photo-redox reaction by thiourea has been derived from spectroscopic, electrochem., and kinetic studies. Thus, thiourea acts as an electron-transfer mediator for the initial photooxidation of 4-methoxybenzyl alc. by the excited flavins. This mechanism has similarities to electron-relay mechanisms in flavoenzymes, for which cysteine sulfenic acid intermediates are proposed. The observation that thiourea mediates flavin photo-redox processes is valuable for the design of more sophisticated photocatalysts based on Nature’s best redox chromophore.

Chemistry – A European Journal published new progress about 30670-30-5. 30670-30-5 belongs to catalysis-chemistry, auxiliary class Polyfluoroalkanes, name is 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecan-1-amine, and the molecular formula is C10H10O6, Safety of 3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-Heptadecafluorodecan-1-amine.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Liu, Rong Qiang published the artcile2-Alkenyldiphenylphosphine oxides and PO-ylides derived thereof in trans selective Horner-Wittig olefination reactions, COA of Formula: C15H15OP, the publication is Synlett (1996), 1195-1196, database is CAplus.

Allylic PO-ylides generated by deprotonation of 2-alkenyldiphenylphosphine oxides with BuLi were used to prepare 1,3-dienes trans-selectively. The (Z/E) ratios of the newly formed double bond are 1:99 when straight-chain, while they were 2:98 to 4:96 when ¦Â-branched aliphatic, and 4:96 to 6:94 when aromatic aldehydes were employed.

Synlett published new progress about 4141-48-4. 4141-48-4 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Allyldiphenylphosphine oxide, and the molecular formula is C15H15OP, COA of Formula: C15H15OP.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Mukhortava, Ann published the artcileEfficient Formation of Site-Specific Protein-DNA Hybrids Using Copper-Free Click Chemistry, SDS of cas: 1395786-30-7, the publication is Bioconjugate Chemistry (2016), 27(7), 1559-1563, database is CAplus and MEDLINE.

Protein-DNA hybrids have become increasingly popular mol. building blocks in bionanotechnol. and single-mol. studies to synergistically combine the programmability of DNA with the chem. diversity of proteins. The growing demand for protein-DNA hybrids requires powerful strategies for their conjugation. Here, we present an efficient two-step method for protein-DNA assembly based on copper-free click chem. The method allows site-specificity and high coupling efficiency, while maintaining the conservation of protein activity. We compare our method to a commonly used protocol of direct linkage of maleimide-modified oligos. We demonstrate the significantly higher yield with a protein-DNA conjugate, which is analyzed using single-mol. force spectroscopy.

Bioconjugate Chemistry published new progress about 1395786-30-7. 1395786-30-7 belongs to catalysis-chemistry, auxiliary class Inhibitor, name is Dbco-maleimide, and the molecular formula is C25H21N3O4, SDS of cas: 1395786-30-7.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Lopez-Vidal, Eva M. published the artcileDeep Learning Enables Discovery of a Short Nuclear Targeting Peptide for Efficient Delivery of Antisense Oligomers, Recommanded Product: Fmoc-Pro-OH, the publication is JACS Au (2021), 1(11), 2009-2020, database is CAplus and MEDLINE.

Therapeutic macromols. such as proteins and oligonucleotides can be highly efficacious but are often limited to extracellular targets due to the cell¡äs impermeable membrane. Cell-penetrating peptides (CPPs) are able to deliver such macromols. into cells, but limited structure-activity relationships and inconsistent literature reports make it difficult to design effective CPPs for a given cargo. For example, polyarginine motifs are common in CPPs, promoting cell uptake at the expense of systemic toxicity. Machine learning may be able to address this challenge by bridging gaps between exptl. data in order to discern sequence-activity relationships that evade our intuition. Our earlier data set and deep learning model led to the design of miniproteins (>40 amino acids) for antisense delivery. Here, we leveraged and expanded our model with data augmentation in the short CPP sequence space of the data set to extrapolate and discover short, low-arginine-content CPPs that would be easier to synthesize and amenable to rapid conjugation to desired cargo, and with minimal in vivo toxicity. The lead predicted peptide, termed P6, is as active as a polyarginine CPP for the delivery of an antisense oligomer, while having only one arginine side chain and 18 total residues. We determined the pentalysine motif and the C-terminal cysteine of P6 to be the main drivers of activity. The antisense conjugate was able to enhance corrective splicing in an animal model to produce functional eGFP in heart tissue in vivo while remaining nontoxic up to a dose of 60 mg/kg. In addition, P6 was able to deliver an enzyme to the cytosol of cells. Our findings suggest that, given a data set of long CPPs, we can discover by extrapolation short, active sequences that deliver antisense oligomers.

JACS Au published new progress about 71989-31-6. 71989-31-6 belongs to catalysis-chemistry, auxiliary class Amino acide derivatives,pyrrolidine, name is Fmoc-Pro-OH, and the molecular formula is C20H19NO4, Recommanded Product: Fmoc-Pro-OH.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Bock, Harald published the artcileSynthesis, NMR spectroscopic characterization and reactions of 2,6-difluorophenylxenon fluoride, 2,6-F₂C₆H₃XeF, SDS of cas: 1206-46-8, the publication is Journal of Fluorine Chemistry (2006), 127(10), 1440-1445, database is CAplus.

[2,6-F₂C₆H₃Xe][BF₄] is quant. transferred into 2,6-F₂C₆H₃XeF in reactions with [NMe₄]F. The latter has been isolated as a colorless solid which is stable in dichloromethane solution at room temperature for approx. 1 h. 2,6-F₂C₆H₃XeF readily reacts with Me₃SiX (X = Cl, Br, CN, NCO, OCOCF₃, OSO₂CF₃, C₆F₅, 2,6-F₂C₆H₃) to give compounds of general compositions 2,6-F₂C₆H₃XeX which were identified by multinuclear NMR experiments Evidence was found for C₆H₅Xe(2,6-F₂C₆H₃) as a product of the reaction with C₆H₅SiF₃.

Journal of Fluorine Chemistry published new progress about 1206-46-8. 1206-46-8 belongs to catalysis-chemistry, auxiliary class Organic Silicones, name is Trimethyl(perfluorophenyl)silane, and the molecular formula is C9H9F5Si, SDS of cas: 1206-46-8.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia

Herrmann, U. published the artcileAggregation of alkylammonium carboxylates and aerosol-OT in apolar solvents studied using absorption and fluorescence probes, Computed Properties of 2016-56-0, the publication is Journal of the American Chemical Society (1979), 101(10), 2665-9, database is CAplus.

By using optical probes, the aggregation of 16 alkylammonium (C₁₀ to C₁₄) carboxylates (C₂ to C₁₁) was studied in dry C₆H₆, C₆H₁₂, and CCl₄, and of as Aerosol-OT in C₆H₆. At the very low concentrations of the absorption (Acridine Orange and iodinee) and fluorescence probes used (octyl-, dodecyl-, and tetradecylammonium 8-anilino-1-naphthalenesulfonates), only the I probe has a significant effect on the aggregation of the surfactant. Critical micelle concentrations were determined by the Corrin-Harkins method, and in a few cases aggregation numbers and association constants were calculated by Adams’ method by using vapor pressure osmometric results. For the alkylamonium carboxylkates the onset of aggregation is gradual, leading to small aggregates (average aggregation number n? = 3) with the monomer population and n? dependent on the concentration In these systems the concept of critical micelle concentration is used only in a operational sense. For Aerosol-OT the onset of micelle formation is sharper, leading to larger aggregates (n? = 10) with the monomer pouplation and aggregation number independent of the concentration The effects of the solvent, the nature of the probe, and the length of the alkylammonium and counterion chains on the aggregation tendency are discussed.

Journal of the American Chemical Society published new progress about 2016-56-0. 2016-56-0 belongs to catalysis-chemistry, auxiliary class Active Esterification, name is Dodecylamineacetate, and the molecular formula is C14H31NO2, Computed Properties of 2016-56-0.

Referemce:
https://courses.lumenlearning.com/boundless-chemistry/chapter/catalysis/,
Catalysis – Wikipedia