Month: October 2022

Wang, Zhaobin; Yang, Ze-Peng; Fu, Gregory C. published the artcile< Quaternary stereocentres via catalytic enantioconvergent nucleophilic substitution reactions of tertiary alkyl halides>, Reference of 1416819-91-4, the main research area is nickel catalytic enantioconvergent nucleophilic substitution tertiary alkyl electrophiles alkenylzirconium.

The development of efficient methods, particularly catalytic and enantioselective processes, for the construction of all-carbon quaternary stereocentres is an important (and difficult) challenge in organic synthesis due to the occurrence of this motif in a range of bioactive mols. One conceptually straightforward and potentially versatile approach is the catalytic enantioconvergent substitution reaction of a readily available racemic tertiary alkyl electrophile by an organometallic nucleophile; however, examples of such processes are rare. Here we demonstrate that a nickel-based chiral catalyst achieves enantioconvergent couplings of a variety of tertiary electrophiles (cyclic and acyclic α-halocarbonyl compounds) with alkenylmetal nucleophiles to form quaternary stereocentres with good yield and enantioselectivity under mild conditions in the presence of a range of functional groups. These couplings, which probably proceed via a radical pathway, provide access to an array of useful families of organic compounds, including intermediates in the total synthesis of two natural products, (-)-eburnamonine and madindoline A.

Nature Chemistry published new progress about Alkenylation catalysts, stereoselective. 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Reference of 1416819-91-4.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Umasankar, Gorakala; Busireddy, Manohar Reddy; Kotamarthi, Bhanuprakash; Karunakar, Galla V.; Rao, Vaidya Jayathirtha published the artcile< Pyrene appended terpyridine derivatives as electrochemiluminescence material for OLEDs: Characterization of photo-physical, thermal and electrochemical properties>, Formula: C7H7NO, the main research area is structure property relationship pyrenyl terpyridine; terpyridine pyrenyl fluorophore preparation photophys electrochem thermal electrochemiluminescence.

Three new terpyridine-appended pyrene derivatives I, II and III have been synthesized by condensation or Suzuki-Miyaura reaction. The photophys., electrochem. and thermal properties of these compounds have been investigated in detail. DFT studies have been carried out to understand the structure-property relationships at the mol. level. The synthesized fluorophores displayed high quantum yield (70-96%) of fluorescence due to triplet to singlet intramol. energy transfer, delayed fluorescence and pos. solvatochromism indicating the presence of an intramol. charge transfer excited state. In addition, they have high thermal decomposition temperatures (Td: 390-450°C), melting temperatures (Tm: 180-220°C); and further, they have suitable oxidation and reduction potentials that make them favorable mols. for OLED fabrications.

Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry published new progress about Claisen condensation. 350-03-8 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO, Formula: C7H7NO.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Zhang, Qun-Liang; Yu, Qin-qin; Ma, Li; Lu, Xuelian; Fan, Qing-Tian; Duan, Tian-Shun; Zhou, Yirong; Zhang, Fang-Lin published the artcile< A Metal-Free Visible-Light Photoredox Construction and Direct C-H Functionalization of Pyridines: Green Synthesis of Polysubstituted Picolinaldehydes>, COA of Formula: C6H4F3N, the main research area is picolinaldehyde preparation green chem; pyridine metal free visible light electrocyclization tandem Minisci reaction.

The development of a novel environmental benign and sustainable synthetic method for highly efficient construction and direct C-H functionalization of N-heterocycles remains a pivotal central research topic for organic and medicinal chem. Herein, a novel visible-light-enabled biomimetic aza-6π electrocyclization for efficient assembly of diverse pyridines and further tandem Minisci-type reaction were developed. A broad spectrum of polysubstituted picolinaldehydes were readily constructed with high efficacy and good functional group tolerance under metal- and oxidant-free conditions.

Journal of Organic Chemistry published new progress about Cyclization, electrophilic. 3796-23-4 belongs to class pyridine-derivatives, and the molecular formula is C6H4F3N, COA of Formula: C6H4F3N.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Hoque, Emdadul Md; Bisht, Ranjana; Unnikrishnan, Anju; Dey, Sayan; Mahamudul Hassan, Mirja Md; Guria, Saikat; Rai, Rama Nand; Sunoj, Raghavan B.; Chattopadhyay, Buddhadeb published the artcile< Iridium-Catalyzed Ligand-Controlled Remote para-Selective C-H Activation and Borylation of Twisted Aromatic Amides>, Synthetic Route of 329214-79-1, the main research area is regioselective remote para borylation CH activation twisted aromatic amide; aryl boronate preparation regioselective remote para borylation aromatic amide; potential energy surface para CH borylation twisted aromatic amide; Borylation; C−H Activation; Density Functional Calculations; Iridium Catalyst; Para Selectivity.

A method of para-selective borylation of fully twisted aromatic amides ArCONBoc2 is described, yielding boronamides 4-pinBC6HnX4-nCONBoc2 (X = alkyl, alkoxy, aryl, halo, CN). The borylation proceeded via an unprecedented substrate-ligand distortion between the twisted aromatic amides and a newly designed ligand framework, 4,5-diaza-9H-fluorene (defa) that is different from the traditionally used ligand (dtbpy) for the C-H borylation reactions. The designed ligand defa has led to the development of a new type of catalytic system that shows excellent para selectivity for a range of aromatic amides. Moreover, the designed ligand has shown excellent reactivity and selectivity for a range of heterocyclic aromatic amides. The identification of key transition states and intermediates using the DFT computations associated with the three regio-isomeric pathways revealed that the most efficient catalytic pathway with the defa ligand leads to the para borylation while in the case of bpy the borylation at the para and meta sites compete.

Angewandte Chemie, International Edition published new progress about Aromatic amides Role: RCT (Reactant), SPN (Synthetic Preparation), RACT (Reactant or Reagent), PREP (Preparation). 329214-79-1 belongs to class pyridine-derivatives, and the molecular formula is C11H16BNO2, Synthetic Route of 329214-79-1.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Barraza, Scott J.; Sindac, Janice A.; Dobry, Craig J.; Delekta, Philip C.; Lee, Pil H.; Miller, David J.; Larsen, Scott D. published the artcile< Synthesis and biological activity of conformationally restricted indole-based inhibitors of neurotropic alphavirus replication: Generation of a three-dimensional pharmacophore>, Application In Synthesis of 3731-53-1, the main research area is indole preparation neurotropic alphavirus replication inhibitor; Antiviral; Conformationally restricted; Neurotropic alphavirus; Pharmacophore; Western equine encephalitis virus.

Authors have previously reported the development of indole-based CNS-active antivirals for the treatment of neurotropic alphavirus infection, but further optimization is impeded by a lack of knowledge of the mol. target and binding site. Herein authors describe the design, synthesis and evaluation of a series of conformationally restricted analogs with the dual objectives of improving potency/selectivity and identifying the most bioactive conformation. Although this campaign was only modestly successful at improving potency, the sharply defined SAR of the rigid analogs enabled the definition of a three-dimensional pharmacophore, which authors believe will be of value in further analog design and virtual screening for alternative antiviral leads.

Bioorganic & Medicinal Chemistry Letters published new progress about Amines Role: RCT (Reactant), RACT (Reactant or Reagent). 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, Application In Synthesis of 3731-53-1.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ma, Cong; Zhao, Chuan-Qi; Xu, Xue-Tao; Li, Zhao-Ming; Wang, Xiang-Yang; Zhang, Kun; Mei, Tian-Sheng published the artcile< Nickel-Catalyzed Carboxylation of Aryl and Heteroaryl Fluorosulfates Using Carbon Dioxide>, Recommanded Product: 3-(Methoxycarbonyl)pyridine, the main research area is aromatic carboxylic acid ester preparation; aryl heteroaryl fluorosulfate carbon dioxide carboxylation nickel catalyst.

The development of efficient and practical methods to construct carboxylic acids using CO2 as a C1 synthon is of great importance. Nickel-catalyzed carboxylation of aryl fluorosulfates and heteroaryl fluorosulfates with CO2 is described, affording arene carboxylic acids with good to excellent yields under mild conditions. In addition, a one-pot phenol fluorosulfation/carboxylation is developed.

Organic Letters published new progress about Aromatic carboxylic acids Role: SPN (Synthetic Preparation), PREP (Preparation). 93-60-7 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO2, Recommanded Product: 3-(Methoxycarbonyl)pyridine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Wu, Guangyu; Liu, Xiaoman; Zhou, Pei; Xu, Zhijun; Hegazy, Mohammad; Huang, Xin; Huang, Yudong published the artcile< The construction of thiol-functionalized DNAsomes with small molecules response and protein release>, HPLC of Formula: 2127-03-9, the main research area is thiol functionalized DNAsome protein release drug delivery system; Pickering emulsion; Polymeric capsule; Self-assembly.

In this work, a poly(N-isopropylacrylamide) polymer (PNIPAAm) was prepared via the photoinduced reversible addition-fragmentation chain transfer (RAFT) polymerization using Ru(bpy)3Cl2·6H2O as photoinitiator. The design and spontaneous assembly of thiol-functionalized DNA-Thiol/PNIPAAm polymeric capsule (DNAsomes) by water-in-oil Pickering emulsion method and effective response with small mols. (Sybr green and phenanthrene) were described. The intermediate product, DNA-Thiol/PNIPAAm conjugates and DNAsomes were characterized by using 1H NMR, dynamic light scattering (DLS), SEM, TEM and UV-vis methods. The obtained results indicated that DNA-Thiol/PNIPAAm constructs assembled in a Pickering emulsion could produce DNA-based spherical DNAsomes with typically 3.3-267.7μm in diameter The DNAsomes showed a vesicle formation approx. 2μm in diameter, resulting in phenanthrene mol. intercalating with DNAsomes. The phenomenon indicated that the DNA-Thiol/PNIPAAm conjugates may have potential applications in recognition polycyclic aromatic hydrocarbon mols. The membrane of the DNAsomes could effective response toward small mols. such as Sybr green or phenanthrene, and DNAsomes has release capability of protein (BSA) under reductive agent glutathione (GSH). Our results highlight the potential of integrating aspects of supramol. and polymer chem. into the design and construction of DNA-polymeric capsule, guest mol. encapsulation, control delivery of drugs, recognition organic polycyclic aromatic hydrocarbon mols. and gene-directed capsule synthesis.

Materials Science & Engineering, C: Materials for Biological Applications published new progress about Bovine serum albumin Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 2127-03-9 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2S2, HPLC of Formula: 2127-03-9.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Santos, Jose L. F.; de Souza, Gabriel L. C. published the artcile< Water hydrogen-bonding effects on the ground and low-lying excited states of dipyridyl isomers>, Computed Properties of 581-47-5, the main research area is dipyridyl water excited state hydrogen bond mol structure.

In this work, we examined the ground and low-lying excited states of six dipyridyl isomers (2,2′-dipyridyl, 2,3′-dipyridyl, 2,4′-dipyridyl, 3,3′-dipyridyl, 3,4′-dipyridyl, and 4,4′-dipyridyl), emphasizing the effects that solvation (water) mols. have on properties such as ground state equilibrium structures, relative energies in terms of conformations and transition states (regarding possible cis-trans interconversions), vertical excitation energies (VEs), generalized oscillator strengths (GOS), and excited state structures. D. functional theory (DFT) and its time-dependent formalism (TD-DFT) were used for determining all the ground state and excited state properties, resp., both being employed with the CAM-B3LYP exchange-correlation functional and the cc-pVTZ basis set. In addition, effects caused by interactions with the solvent environment were probed by means of using two different approaches: (i) the integral equation formalism polarizable continuum model (IEF-PCM) and (ii) a composite solvation model (CSM) through the incorporation of explicit water mols. in combination with the IEF-PCM. In general, a decrease in the relative energies regarding a given cis/trans counterpart is noticed when solvation is considered independently from the model used; all the dipyridyl cis/trans isomers became (practically) isoenergetical due to dipyridyl-H2O hydrogen-bonding interactions. Moreover, the interconversion barriers were also found to be lowered due to solvation effects. For instance, the energy barrier in terms of interconversion of the trans 2,2′-dipyridyl to the cis 2,2′-dipyridyl was determined as (approx.) 67% of the corresponding value obtained in the gas-phase. Although no major differences regarding the values of the VEs associated to a bright state are suggested from the comparison between the results obtained for a given isomer through the consideration of solvation and those corresponding determined in the gas-phase, the GOS are all increased when solvation is considered, suggesting an enhancement in the photoabsorption of all the isomers when in presence of solvent. In addition and in contrast to what was seen previously in the case of the gas-phase, 4,4′-dipyridyl presented a bright state among the five lowest-lying excited singlets (accessible at the UVC energy region), which is located at 5.49 eV (with GOS = 0.4465) at the TD-DFT/CAM-B3LYP/cc-pVTZ level of theory in water (IEF-PCM) and at 5.47 eV (with GOS = 0.5331) at the same level of theory with the CSM. Given that no significant change was noticed in the optimized structures for the excited states, it is possible to infer that all the compounds will decompose through photo decomposition (chem. reaction occurring in the excited state) rather than direct photolysis when in solution

Journal of Molecular Liquids published new progress about Conformation. 581-47-5 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2, Computed Properties of 581-47-5.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

He, Qidi; Cai, Shuangshuang; Wu, Jinghao; Hu, Ou; Liang, Lushan; Chen, Zuanguang published the artcile< Determination of tuberculosis-related volatile organic biomarker methyl nicotinate in vapor using fluorescent assay based on quantum dots and cobalt-containing porphyrin nanosheets>, Application In Synthesis of 93-60-7, the main research area is methyl nicotinate vapor fluorescent assay tuberculosis Mycobacterium; Fluorescent assay; Methyl nicotinate; Nanoporphyrin; Quantum dots; Tuberculosis; Volatile organic biomarker.

Me nicotinate (MN) is a representative and typical volatile organic marker of Mycobacterium tuberculosis, and the specific detection of MN in human breath facilitates non-invasive, rapid, and accurate epidemic screening of tuberculosis infection. Herein, we constructed a fluorescent assay consisted of CdTe quantum dots (QD) and cobalt-metalized tetrakis(4-carboxyphenyl) porphyrin (CoTCPP) nanosheets to determine Me nicotinate (MN) in vapor samples. Red-emission QD (λex=370 nm, λem=658 nm) acts as signal switches whose fluorescence signals can be effectively quenched by CoTCPP nanosheets but restored in the presence of MN. The strategy relied on the distinct binding affinity of cobalt ion and MN. MN restored the fluorescence of QD quenched by CoTCPP in a concentration-dependent manner, which exhibited a well-linear relationship in the range 1-100 μM, and a limit of detection of 0.59 μM. The proposed platform showed sensitivity and selectivity to detect MN in vapor samples with satisfactory RSD below 3.33%. The method is cheap, simple, and relatively rapid (detected within 4 min), which suggests a potential in tuberculosis diagnosis in resource- and professional-lacked areas.

Microchimica Acta published new progress about Fluorescence immunoassay. 93-60-7 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO2, Application In Synthesis of 93-60-7.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Race, Nicholas J.; Yuan, Qianjia; Sigman, Matthew S. published the artcile< Enantioselective C2-Alkylation of Indoles through a Redox-Relay Heck Reaction of 2-Indole Triflates>, Related Products of 1416819-91-4, the main research area is enantioselective alkylation indole Heck triflate; Heck reaction; asymmetric catalysis; enantioselective catalysis; indole; palladium.

A palladium-catalyzed enantioselective redox-relay Heck reaction of 2-indole triflates and disubstituted alkenes is reported. This process combines readily available indole triflates with a variety of alkenes to afford a range of indole derivatives bearing a stereocenter adjacent to C2. Enantioselectivity is achieved through use of a simple pyridine-oxazoline ligand. Tuning the electronics of the indole, through judicious choice of N-protecting group, is required to ensure selective β-hydride elimination away from the indole core. Utility of this method is highlighted in a modular formal synthesis of an S1P1 agonist precursor developed by Merck.

Chemistry – A European Journal published new progress about Alkylation. 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, Related Products of 1416819-91-4.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem