Month: December 2022

Elsby, Matthew R. published the artcileInfluence of N-Heterocyclic Carbene Steric Bulk on Selectivity in Nickel Catalyzed C-H Bond Silylation, Germylation, and Stannylation, Safety of Trimethyl(perfluorophenyl)silane, the publication is Organometallics (2019), 38(2), 436-450, database is CAplus.

A series of Ni(0) compounds supported by electronically similar N-heterocyclic carbene (NHC) ancillary ligands with a range of %V_bur were used as catalysts for aryl C-H bond silylation, germylation, and stannylation. The NHC steric bulk strongly influenced the selectivity of C-H functionalization to give new carbon-heteroatom bonds vs. alkene hydroarylation, despite little structural change in the resting state of the catalysts. Studies were performed by reacting C₆F₅H and H₂C:CHER₃ (ER₃ = SnBu₃, GePh₃, SiMe₃) using catalytic amounts of Ni(COD)₂ and NHC ligands IPr, IMes, IBn, and ⁱPr₂Im. Catalytic C-H stannylation to give C₆F₅SnBu₃ was facile with all ligands. The catalytic C-H germylation reaction was more difficult than stannylation but was demonstrated using H₂C:CHGePh₃ to give C₆F₅GePh₃ for all but the largest NHC. The bulkiest NHC, IPr, gave a 96:4 ratio of the hydroarylation product C₆F₅CH₂CH₂GePh₃ vs. C₆F₅GePh₃. The C-H silylation reactions required the highest temperatures and gave selective silylation product C₆F₅SiMe₃ only for the smallest IBn and ⁱPr₂Im NHC ligands. Using the larger IMes carbene resulted in a 66:34 mixture of silylation and hydroarylation products, and the largest NHC, IPr, gave exclusive conversion to the hydroarylation product, C₆F₅CH₂CH₂SiMe₃. DFT calculations are provided that give insight into the mechanism and key reaction steps, such as the relative difficulty of the critical ¦Â-Sn, Ge, and Si elimination steps.

Organometallics 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, Safety of Trimethyl(perfluorophenyl)silane.

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

Lee, David Y. W. published the artcileAsymmetric total synthesis of tetrahydroprotoberberine derivatives and evaluation of their binding affinities at dopamine receptors, Recommanded Product: 1,2-Dimethoxy-4-(2-nitrovinyl)benzene, the publication is Bioorganic & Medicinal Chemistry Letters (2017), 27(6), 1437-1440, database is CAplus and MEDLINE.

Cocaine addiction remains a serious challenge for clin. and medical research because there is no effective pharmacol. treatment. L-THP I, a natural product isolated from Corydalis yanhusuo W. T. Wang, is one of the most frequently used traditional herbs to treat drug addiction in China. Our laboratory first reported that its demethylated metabolites had high affinity at dopamine D1, D2, and D5 receptors. Here we report the chem. synthesis of these metabolites and other derivatives and their binding affinities at dopamine receptors. The synthesis of these bioactive metabolites will allow further in vivo study of their potential in treating cocaine addiction.

Bioorganic & Medicinal Chemistry Letters published new progress about 4230-93-7. 4230-93-7 belongs to catalysis-chemistry, auxiliary class Alkenyl,Nitro Compound,Benzene,Ether, name is 1,2-Dimethoxy-4-(2-nitrovinyl)benzene, and the molecular formula is C10H11NO4, Recommanded Product: 1,2-Dimethoxy-4-(2-nitrovinyl)benzene.

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

Su, Jianpeng published the artcileEbsulfur as a potent scaffold for inhibition and labelling of New Delhi metallo-¦Â-lactamase-1 in vitro and in vivo, Synthetic Route of 119-80-2, the publication is Bioorganic Chemistry (2019), 192-201, database is CAplus and MEDLINE.

The superbug infection caused by New Delhi metallo-¦Â-lactamase (NDM-1) has grown into an emerging threat, labeling and inhibition of NDM-1 has proven challenging due to its shuttling between pathogenic bacteria. Here, we report a potent covalent scaffold, ebsulfur, for targeting the protein in vitro and in vivo. Enzymic kinetic study indicated that eighteen ebsulfurs gained except 1a-b and 1f inhibited NDM-1, exhibiting an IC₅₀ value ranging of 0.16-9 ¦ÌM, and 1g was found to be the best, dose- and time-dependent inhibitor with an IC₅₀ of 0.16 ¦ÌM. Also, these ebsulfurs effectively restored the antibacterial activity of cefazolin against E. coli expressing NDM-1, and the best effect was observed to be from 1g, 1i and 1n, resulting in an 256-fold reduction in MIC of the antibiotic at a dose of 16 ¦Ìg/mL. The equilibrium dialysis study implied that the ebsulfur disrupted the coordination of one Zn(II) ion at active site of NDM-1. Labeling of NDM-1 using a constructed fluorescent ebsulfur Ebs-R suggested that the inhibitor covalently bound to the target through SDS-PAGE anal. in vitro. Also, labeling NDM-1 in living E. coli cells with Ebs-R by confocal microscopic imaging showed the real-time distribution change process of intracellular recombinant protein NDM-1. Moreover, the cytotoxicity of these ebsulfurs against L929 mouse fibroblastic cells was tested, and their capability to restore antibacterial activity of antibiotic against clin. strains E. coli EC08 producing NDM-1 was determined The ebsulfur scaffold proposed here is valuable for development of the covalent irreversible inhibitors of NDM-1, and also for labeling the target in vitro and in vivo.

Bioorganic Chemistry published new progress about 119-80-2. 119-80-2 belongs to catalysis-chemistry, auxiliary class sulfides,Carboxylic acid,Benzene, name is 2,2′-Dithiodibenzoic acid, and the molecular formula is C8H10N2O2, Synthetic Route of 119-80-2.

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

Hu, Qi-Long published the artcileDemethylative alkylation of methionine residue by employing the sulfonium as the key intermediate, Application of Fmoc-Pro-OH, the publication is Organic Letters (2021), 23(21), 8543-8548, database is CAplus and MEDLINE.

Methionine (Met) offers a valuable handle to achieve peptide chem. modification owing to its unique thioether functional group. In contrast with cysteine, the site-selective functionalization of the hydrophobic and redox-sensitive thioether motif on peptides is still challenging, and strategies for diversification on the Met residue are rarely disclosed. Herein we report a transition-metal-free and redox-neutral approach for Met diversification with substrate diversity, which could be applied to synthesize cyclic peptides.

Organic Letters 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, Application of Fmoc-Pro-OH.

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

Yue, Fuyang published the artcileLight-Mediated Defluorosilylation of ¦Á-Trifluoromethyl Arylalkenes through Hydrogen Atom Transfer, Product Details of C15H24S, the publication is Organic Letters (2022), 24(22), 4019-4023, database is CAplus and MEDLINE.

Herein, the authors report a direct, light-mediated defluorosilylation protocol for converting ¦Á-trifluoromethyl arylalkenes and alkyl silanes into ¦Ã,¦Ã-difluoroallylic compounds via a combination of photoredox catalysis and H atom transfer. The clean, convenient protocol can be scaled to the gram level, and its mild conditions make it very suitable for late-stage functionalization of complex natural products and drugs.

Organic Letters published new progress about 22693-41-0. 22693-41-0 belongs to catalysis-chemistry, auxiliary class Other Functionalization Reagent, name is 2,4,6-Triisopropylbenzenethiol, and the molecular formula is C5H9IO2, Product Details of C15H24S.

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

Li, Wei published the artcileTransition metal-free iodine-promoted haloamination of unfunctionalized olefins, COA of Formula: C11H19N, the publication is RSC Advances (2014), 4(26), 13509-13513, database is CAplus.

A transition metal-free route to 3-halopiperidines and 2-halomethylpiperidines was described. In the presence of iodine, potassium persulfate and a suitable halogen source, intramol. haloamination of 4-penten-1-amines and 5-hexen-1-amines proceeded readily, leading to the corresponding substituted piperidines in good isolated yields.

RSC Advances published new progress about 928836-00-4. 928836-00-4 belongs to catalysis-chemistry, auxiliary class Alkenyl,Amine,Aliphatic hydrocarbon chain, name is 2,2-Diallylpent-4-en-1-amine, and the molecular formula is C11H19N, COA of Formula: C11H19N.

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

Rong, Guangwei published the artcileIron-catalyzed decarboxylative methylation of ¦Á,¦Â-unsaturated acids under ligand-free conditions, SDS of cas: 1772-76-5, the publication is Tetrahedron (2014), 70(34), 5033-5037, database is CAplus.

It is the first time to find that iron-catalyzed decarboxylative methylation of ¦Á,¦Â-unsaturated acids could be performed in the absence of any ligands. During the reaction, the configuration of the double bond could be retained. It is noteworthy that di-tert-Bu peroxide (DTBP) was employed not only as the oxidant, but also as the Me source.

Tetrahedron published new progress about 1772-76-5. 1772-76-5 belongs to catalysis-chemistry, auxiliary class Benzenes, name is (E)-3-(3-Nitrophenyl)acrylic acid, and the molecular formula is C9H7NO4, SDS of cas: 1772-76-5.

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

Li, Ren-Zhe published the artcileAsymmetric O-propargylation of secondary aliphatic alcohols, Safety of Difluorodiphenylsilane, the publication is Nature Catalysis (2020), 3(8), 672-680, database is CAplus.

Here, we report the development of a base-free, Cu-catalyzed propargylic substitution reaction that enables the efficient, asym. O-propargylation of secondary aliphatic alcs. Mechanistic studies implied key factors to slow down the undesired decomposition process of electrophiles in this reaction, which opened up the possibility of using secondary aliphatic alcs. as nucleophilic substrates. This asym. O-alkylation reaction proceeds under almost neutral conditions, tolerates a broad scope of functional groups and showed remarkable chemoselectivities. This method was amenable to the modification of natural products and com. drugs. The products obtained was readily elaborated to various classes of enantioenriched ¦Á,¦Á’-disubstituted ethers that were difficult to access by other methods.

Nature Catalysis 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 C12H10F2Si, Safety of Difluorodiphenylsilane.

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

Lv, Cong published the artcileFrom amides to urea derivatives or carbamates with chemospecific C-C bond cleavage at room temperature, Name: 4-Nitrophenylacetic acid, the publication is Organic Chemistry Frontiers (2022), 9(5), 1354-1363, database is CAplus.

Herein, a significant advancement in this area and present a general method for copper-catalyzed chemospecific C-C bond cleavage of amides to synthesize urea derivatives and carbamates at room temperature was reported. A catalytic process via a resonant six-membered N,O-chelated copper cycle and superoxide radical was proposed according to mechanistic and control experiments The combination of chelation assistance and radical oxygenation strategies opened a door for C-C bond cleavage of common substrates which possess multiple reactive sites and was envision that this broadly applicable method will be of great interest in organic synthesis, the pharmaceutical industry and the agrochem. industry.

Organic Chemistry Frontiers published new progress about 104-03-0. 104-03-0 belongs to catalysis-chemistry, auxiliary class Nitro Compound,Carboxylic acid,Benzene, name is 4-Nitrophenylacetic acid, and the molecular formula is C8H7NO4, Name: 4-Nitrophenylacetic acid.

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

Chen, Jiexiu published the artcileEnhanced stability of oral insulin in targeted peptide ligand trimethyl chitosan nanoparticles against trypsin, Application In Synthesis of 71079-09-9, the publication is Journal of Microencapsulation (2015), 32(7), 632-641, database is CAplus and MEDLINE.

Oral insulin delivery is often limited by protease degradation 2-(Dimethylamino)-2-oxoethyl 4-(4-guanidinobenzoyloxy)phenylacetate methanesulfonate (Camostat mesylate) is reported to have the ability to inhibit trypsin activity, which is the main protease responsible for protein degradation This study attempted to form a novel nanoparticle by covalently conjugating 4-(2-(2-aminoethylamino)-2-oxoethyl)phenyl 4-guanidinobenzoyloxy (FOY-251), an active derivative of camostat mesylate, to the backbone of poly (¦Ã-glutamic acid) (¦Ã-PGA), in order to improve insulin stability against protease. Goblet cell targeting CSKSSDYQC (CSK) peptide was demonstrated to effectively improve the epithelial absorption of insulin. Therefore, the novel nanoparticle was prepared by mixing cationic peptide modified tri-Me chitosan (TMC-CSK) with anionic ¦ÃPGA-FOY conjugate using multi-ion crosslinked method. Results showed that not only the ¦ÃPGA-FOY conjugate but also the prepared novel nanoparticle could inhibit trypsin activity both in vitro environment and on the intestinal mucosal surface. This study would be beneficial for peptide modified nanoparticles in oral insulin delivery.

Journal of Microencapsulation published new progress about 71079-09-9. 71079-09-9 belongs to catalysis-chemistry, auxiliary class Salt,Carboxylic acid,Carbamidine,Amine,Benzene,Ester,Protease,Ser/Thr Protease, name is 2-(4-((4-Guanidinobenzoyl)oxy)phenyl)acetic acid methanesulfonic acid salt, and the molecular formula is C17H19N3O7S, Application In Synthesis of 71079-09-9.

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