Month: December 2022

Tu, Jianzhuo published the artcileIntramolecular (4+3) Cycloadditions of Oxidopyridinium Ions: Towards Daphnicyclidin A, Recommanded Product: Allyldiphenylphosphine oxide, the publication is Chemistry – A European Journal (2022), 28(41), e202200370, database is CAplus and MEDLINE.

N-alkylation of 5-hydroxynicotinic acid esters with electrophiles containing diene functionality produces salts that underwent intramol. (4+3) cycloaddition reactions upon heating in the presence of base. Initial studies used a three-carbon tether to join the pyridinium ion and diene, revealing some aspects of the inherent selectivity of the reaction with such substrates. Much more challenging was the synthesis of related species possessing only a two-carbon tether. Nevertheless, the cycloaddition of such compounds was successful, leading directly to the ABC ring system of the alkaloid daphnicyclidin A.

Chemistry – A European Journal 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 C15H19BO2, Recommanded Product: Allyldiphenylphosphine oxide.

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

Zhang, Haoqi published the artcileSynthesis of Novel Heterocycles by Amide Activation and Umpolung Cyclization, Related Products of catalysis-chemistry, the publication is Organic Letters (2020), 22(6), 2376-2380, database is CAplus and MEDLINE.

Herein, we report a metal-free synthesis of cyclic amidines, oxazines, and an oxazinone under mild conditions by electrophilic amide activation. This strategy features an unusual Umpolung cyclization mode and enables the smooth union of ¦Á-aryl amides and diverse alkylazides, effectively rerouting our previously reported ¦Á-amination transform.

Organic Letters 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 C8H6KNO4S, Related Products of catalysis-chemistry.

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

Light, B. published the artcileEffect of triethylenetetramine dihydrochloride on the antibiotic susceptibility of Pseudomonas aeruginosa, Quality Control of 38260-01-4, the publication is Antimicrobial Agents and Chemotherapy (1978), 13(6), 979-84, database is CAplus and MEDLINE.

A chelating agent, triethylenetetramine-2HCl [38260-01-4], interacted synergistically in vitro with both gentamicin [1403-66-3] and carbenicillin [4697-36-3] against a clin. isolate of P. aeruginosa designated Ps 15. The minimal inhibitory concentrations of carbenicillin and gentamicin for Ps 15 in a 50% serum-Trypticase soy broth were 250 and 72.9 ¦Ìg/mL, resp. However, addition of triethylenetetramine-2HCl to the 50% serum-Trypticase soy broth decreased the minimal inhibitory concentrations of both antibiotics ?10-fold. A comparison of the growth of Ps 15 in 50% serum-Trypticase soy broth containing either of the antibiotics showed that a rapid decrease in the percentage of survivors only occurred when the chelating agent was present.

Antimicrobial Agents and Chemotherapy published new progress about 38260-01-4. 38260-01-4 belongs to catalysis-chemistry, auxiliary class Chelating Agents, name is N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride, and the molecular formula is C6H20Cl2N4, Quality Control of 38260-01-4.

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

Light, B. published the artcileThe effect of triethylenetetramine dihydrochloride on the in vivo susceptibility of Pseudomonas aeruginosa to gentamicin, Category: catalysis-chemistry, the publication is Journal of Antibiotics (1979), 32(8), 834-8, database is CAplus and MEDLINE.

Triethylenetetramine-2HCl (I) [38260-01-4] increased the efficacy of gentamicin [1403-66-3] in vivo against a clin. isolate of P. aeruginosa, designated Ps 15. Mice which were inoculated with 10 x LD₅₀ of Ps 15 and treated with doses of 2?16 mg of gentamicin/kg/day all died. However, treatment with 8 mg of gentamicin/kg/day plus 30 mg I/day markedly reduced the mortality. The combined therapy also reduced the number of viable organisms that accumulated in the kidney during a 24-h period post inoculation. When a dosage level of 8 mg of gentamicin was exceeded in the combined treatment regimen, all of the infected mice died, and a high concentration of endotoxin could be detected in the mouse sera by the limulus assay.

Journal of Antibiotics published new progress about 38260-01-4. 38260-01-4 belongs to catalysis-chemistry, auxiliary class Chelating Agents, name is N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride, and the molecular formula is C6H20Cl2N4, Category: catalysis-chemistry.

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

Schroth, Werner published the artcileSynthesis and chemical behavior of 6-sec-amino-1,3-thiazine-2-thiones, Application In Synthesis of 6972-05-0, the publication is Monatshefte fuer Chemie (1988), 119(4), 463-76, database is CAplus.

The title compounds I (R = H, Me, OMe, Cl, Br; NR¹R² = pyrrolidino, piperidino, morpholino) have been prepared by ring transformation reactions of the isomeric 2-sec-amino-1,3-thiazine-6-thiones II (NR³R⁴ = NMe₂, pyrrolidino, morpholino) via R²R¹NCSCH:C(C₆H₄R-4)NHCSNR³R⁴ (III) and via cyclocondensation reactions of thiocarboxamides R²R¹NCSCH:C(C₆H₄R-4)NH₂, and R²R¹N⁺:CClCH:C(C₆H₄R-4)OEt BF₄^– obtained from 4-RC₆H₄COCH:CCl₂. The pathways differ specifically in scope and limitations. On the other hand III also react with alkylating agents to give 2,6-di-sec-amino-1,3-thiazinium salts, which are also available via alkylation of I and aminolysis.

Monatshefte fuer Chemie published new progress about 6972-05-0. 6972-05-0 belongs to catalysis-chemistry, auxiliary class Thiourea,Amine,Aliphatic hydrocarbon chain,Amide, name is 1,1-Dimethylthiourea, and the molecular formula is C3H8N2S, Application In Synthesis of 6972-05-0.

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

Egetenmeyer, Simone published the artcileA 5′-cap for DNA probes binding RNA target strands, Computed Properties of 1798-04-5, the publication is Chemistry – A European Journal (2011), 17(42), 11813-11827, S11813/1-S11813/37, database is CAplus and MEDLINE.

Detecting short RNA strands with high fidelity at any of the bases of their sequence, including the termini, can be challenging, since fraying, wobbling, and refolding all compete with canonical base pairing. We performed a search for 5′-substituents of oligodeoxynucleotides that increase base pairing fidelity at the terminus of duplexes with RNA target strands. From a total of over 70 caps, differing in stacking moiety and linker, a phosphodiester-linked sequence of the residues of L-prolinol, glycine, and oxolinic acid, dubbed ogOA, was identified as a 5′-cap that stabilizes any of the four canonical base pairs, with ¦¤T_m values of up to +13.1 ¡ãC for an octamer. At the same time, the cap increases discrimination against any of the 12 possible terminal mismatches, including mismatches that are more stable than their perfectly matched counterparts in the control duplex, such as A:A. A probe with the cap also showed increased selectivity in the detection of two closely related microRNAs, let7c and let7a, with a ¦¤T_m value of 9.2 ¡ãC. Melting curves also yielded thermodn. data that shed light on the uniformity of mol. recognition in the sequence space of DNA:DNA and DNA:RNA duplexes. Hybridization probes with fidelity-enhancing caps should find applications in the individual and parallel detection of biol. active RNA species.

Chemistry – A European Journal published new progress about 1798-04-5. 1798-04-5 belongs to catalysis-chemistry, auxiliary class Carboxylic acid,Benzene,Ether, name is 2-(4-(tert-Butyl)phenoxy)acetic acid, and the molecular formula is C12H16O3, Computed Properties of 1798-04-5.

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

Habte-Tsion, H.-Michael published the artcileThe effects of fish meal substitution by clam meal on the growth and health of Florida pompano (Trachinotus carolinus), Recommanded Product: Docosahexaenoic Acid, the publication is Scientific Reports (2022), 12(1), 7696, database is CAplus and MEDLINE.

A 12-wk feeding trial was conducted to evaluate the effects of fish meal (FM) substitution by clam meal (CM, at 10%, 20% and 30% of the diet) on the growth, feed utilization, hepatic antioxidant enzymes, plasma parameters, fatty acid and amino acid composition, and gut microbiome of juvenile Florida pompano, Trachinotus carolinus. The results indicated that: (1) juveniles fed 10% and 20% CM had a significantly higher final weight than the group fed the control (0% CM); and the control group also showed significantly lower weight gain, feed intake, protein retention value, whole-body crude protein and total amino acids composition, but higher hepatosomatic index and whole-body crude fat; (2) hepatic peroxide content and superoxide dismutase activity were not significantly affected by the substitution of CM, but it did affect glutathione peroxidase activity, with higher levels found in fish fed 30% CM compared to 0% and 10% CM; (3) plasma total protein, alk. phosphatase, alanine aminotransferase, and IgM showed no significant differences among the treatments; (4) there were no significant differences among treatments in terms of fatty acids composition and microbial diversity. Overall, this study concluded that CM has comparable benefit in the diet of Florida pompano as FM does.

Scientific Reports published new progress about 6217-54-5. 6217-54-5 belongs to catalysis-chemistry, auxiliary class Alkenyl,Carboxylic acid,Aliphatic hydrocarbon chain,Metabolic Enzyme,RAR/RXR,Natural product, name is Docosahexaenoic Acid, and the molecular formula is C22H32O2, Recommanded Product: Docosahexaenoic Acid.

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

Nelson, Hope published the artcilePractical Chemoselective Acylation: Organocatalytic Chemodivergent Esterification and Amidation of Amino Alcohols with N-Carbonylimidazoles, SDS of cas: 104-03-0, the publication is Angewandte Chemie, International Edition (2021), 60(42), 22818-22825, database is CAplus and MEDLINE.

Here, the N-carbonylimidazoles enable catalytic chemodivergent aniline or alc. acylation in the presence of pyridinium ions or 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), was reported. Both acylation reactions display high and broad chemoselectivity for the target group. Unprecedented levels of chemoselectivity were observed in the DBU-catalyzed esterification: A single esterification product was obtained from a mol. containing primary aniline, alc., phenol, secondary amide, and N-H indole groups. These acylation reactions are highly practical as they involve only readily available, inexpensive, and relatively safe reagents; can be performed on a multigram scale; and can be used on carboxylic acids directly by in situ formation of the acylimidazole electrophile.

Angewandte Chemie, International Edition 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, SDS of cas: 104-03-0.

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

Lenker, Heather K. published the artcilePhospha-Michael Additions to Activated Internal Alkenes: Steric and Electronic Effects, Safety of Dimesitylphosphine oxide, the publication is Journal of Organic Chemistry (2012), 77(3), 1378-1385, database is CAplus and MEDLINE.

The addition of P(O)-H bonds to internal alkenes has been accomplished under solvent-free conditions without the addition of a catalyst or radical initiator. Using a prototypical secondary phosphine oxide, a range of substrates including cinnamates, crotonates, coumarins, sulfones, and chalcones were successfully functionalized. Highly activated acceptors such as isopropylidenemalononitrile and Et 2-cyano-3-methyl-2-butenoate underwent the phospha-Michael reaction upon simple trituration of the reagents at room temperature, whereas less activated substrates such as Et cinnamate and Me crotonate required heating (>150 ¡ãC) in a microwave reactor to achieve significant consumption of the starting alkenes. For the latter alkenes, a competing reaction involving disproportionation of the ditolylphosphine oxide into ditolylphosphinic acid and ditolylphosphine was observed at the high temperatures needed to promote the addition reaction.

Journal of Organic Chemistry published new progress about 23897-16-7. 23897-16-7 belongs to catalysis-chemistry, auxiliary class Aryl phosphine ligand,Mono-phosphine Ligands, name is Dimesitylphosphine oxide, and the molecular formula is C18H23OP, Safety of Dimesitylphosphine oxide.

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

Thomson, George published the artcileA chain model for polyelectrolytes. IX. The effects of chain length and charge on the friction constant, Recommanded Product: N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride, the publication is Journal of the American Chemical Society (1963), 85(17), 2537-44, database is CAplus.

cf. CA 58, 9671g. Measurements are reported of self-diffusion and viscosity as a function of chain length and charge for some protonated and unprotonated amines and for some disulfonate ions. It is found that the Peterlin theory of diffusion of short-chain mols. (CA 46, 8935a) is an accurate description of real systems. The P. theory of viscosity is qual. correct but quant. in error by a factor of 2. The placement of 2 charges on an ethylenimine leads to an extended mol. configuration. The possibility of H bonding between uncharged ethylenimines and the water leads to zero slip between mol. and solvent. Therefore, classical hydrodynamic conditions are satisfied and the system behaves differently (larger friction constant) from what would be expected from other studies in nonhydrogen-bonding solvents. When charges are placed on the ion the local water structure is modified, decreasing the efficacy (or even possibility) of H bonding. There is a range of variables wherein the friction constant per bead drops on going from the neutral mol. to the bolion (CA 52, 19353e), because of the change in solvent interactions. The transition from simple ion to polyion requires more than 5 charges per ion and longer chain lengths than considered herein.

Journal of the American Chemical Society published new progress about 38260-01-4. 38260-01-4 belongs to catalysis-chemistry, auxiliary class Chelating Agents, name is N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride, and the molecular formula is C14H12O2, Recommanded Product: N1,N1′-(Ethane-1,2-diyl)bis(ethane-1,2-diamine) dihydrochloride.

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