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So far, in addition to halogen atoms, other non-metallic atoms can become part of the aromatic heterocycle, and the target ring system is still aromatic.Cao, Jing-Pei; Zhao, Xiao-Yan; Morishita, Kayoko; Wei, Xian-Yong; Takarada, Takayuki researched the compound: 3-Methyl-1H-pyrrole( cas:616-43-3 ).Product Details of 616-43-3.They published the article 《Fractionation and identification of organic nitrogen species from bio-oil produced by fast pyrolysis of sewage sludge》 about this compound( cas:616-43-3 ) in Bioresource Technology. Keywords: organic nitrogen species bio oil pyrolysis sewage sludge pyrolysis. We’ll tell you more about this compound (cas:616-43-3).

Pyrolysis of sewage sludge was performed at 500° and a sweeping gas flow rate of 300 cm3/min in a drop tube furnace. Liquid fraction (i.e., bio-oil) from the sewage sludge pyrolysis was separated by silica-gel column chromatog. (SGCC) with different solvents, including mixed solvents, as eluants. Alkanenitriles (C13-C18), oleamide, alkenenitrile, fatty acid amides and aromatic nitrogen species were fractionated from the bio-oil by SGCC and analyzed with a gas chromatog./mass spectrometry (GC/MS). Most of the GC/MS-detectable organic nitrogen species (ONSs) are lactams, amides and N-heterocyclic compounds, among which acetamide is the most abundant. N-heterocyclics with 1-3 rings, including pyrrole, pyridine, indole, benzoimidazole, carbazole, norharman and harman, were observed The lactams detected include pyrrolidin-2-one, succinimide, phthalimide, glutarimide, piperidin-2-one and 3-isobutylhexahydropyrrolo[1,2-a]pyrazine-1,4-dione, all of which should be formed via decarboxylation and cyclization of γ- and δ-amino acids. Such a procedure provides an effective approach to fractionation and identification of ONSs from bio-oil produced by fast pyrolysis of sewage sludge.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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In organic chemistry, atoms other than carbon and hydrogen are generally referred to as heteroatoms. The most common heteroatoms are nitrogen, oxygen and sulfur. Now I present to you an article called Formation and pharmacokinetics of the active drug candoxatrilat in mouse, rat, rabbit, dog and man following administration of the prodrug candoxatril, published in 1997-10-31, which mentions a compound: 3685-23-2, mainly applied to candoxatril candoxatrilat pharmacokinetics species, Recommanded Product: 3685-23-2.

Candoxatrilat, an active neutral endopeptidase inhibitor, was released rapidly from the inactive prodrug candoxatril in vivo in the mouse, rat, rabbit, dog and man. Oral doses of [14C]candoxatril were cleared rapidly, mostly by ester hydrolysis to candoxatrilat, in the mouse, dog and man. A complementary i.v. study in man with [14C]candoxatrilat showed that the active drug was virtually completely renally cleared. Neither candoxatril nor candoxatrilat underwent chiral inversion in man. The systemic availability of candoxatrilat from the oral prodrug was estimated to be 88, 53, 42, 17 and 32% in the mouse, rat, rabbit, dog and man resp. Plasma clearance of candoxatril was too rapid to enable pharmacokinetic parameter calculation in mice and rabbits; for man, the apparent oral clearance was 57.9 mL/min/kg and the elimination half-life was 0.46 h. For i.v. candoxatrilat, total plasma clearance values were 32, 15, 5.5, 5.8 and 1.9 mL/min/kg for the mouse, rat, rabbit, dog and man, resp. Renal clearance values were 8.7, 7.2, 2.9 and 1.7 mL/min/kg for the mouse, rat, dog and man, resp., and these approximated the resp. glomerular filtration rates. Allometric scaling with respect to body weight across the species allowed reasonable prediction of the above 2 clearance parameters in man.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Raman spectra of pyrroles and a few derivatives》. Authors are Stern, A.; Thalmayer, K..The article about the compound:3-Methyl-1H-pyrrolecas:616-43-3,SMILESS:CC1=CNC=C1).Application of 616-43-3. Through the article, more information about this compound (cas:616-43-3) is conveyed.

Raman spectra were obtained for pyrrole and the following derivatives, 3-Me; 2,3-di-Me; 2,4-di-Et; 2-Et; 2-Me-4-Et; 2,4-di-Me-3,5-di-Et; 2,4-di-Et-3-Pr; 2,4-di-Et-3-Me. In pure pyrrole, frequencies corresponding to CC and CN double-bond vibrations and those of the methylene group were detected. These had only been found previously in substituted pyrroles. This indicates that free pyrrole also contains some of the pyrrolinene form and the earlier model of the mol. as proposed by Bonino, Manzoni-Ansidei and Pratesi (cf. C. A. 28,5336.8) must be modified.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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Most of the natural products isolated at present are heterocyclic compounds, so heterocyclic compounds occupy an important position in the research of organic chemistry. A compound: 56413-95-7, is researched, SMILESS is N#CC1=NC(Cl)=C(Cl)N=C1C#N, Molecular C6Cl2N4Journal, Journal of Porphyrins and Phthalocyanines called Syntheses of Octa(dialkylamino)azaphthalocyanines, Author is Morkved, Eva H.; Kjosen, Helge; Ossletten, Hege; Erchak, Nikolai, the main research direction is azaphthalocyanine dialkylamino copper nickel preparation; transition metal dialkylamino azaphthalocyanine preparation; pyrazine diiminoimide cyclization dialkylamino azaphthalocyanine preparation.Product Details of 56413-95-7.

Ni(II) octa(4-morpholinyl)- (11a) and Cu(II) octa(1-pyrrolidinyl)- (11b) azaphthalocyanines were prepared from the corresponding pyrazine diiminoimides (10). The precursor pyrazine dicarbonitriles (2) gave 6-cyanopyrazine-5-alkyl carboximidates (3-9) as stable intermediates when reacted with NH3 and catalytic amounts of Na alkoxide in alcs. 3-9 Were converted to the diiminoimides 10 upon reflux in PrOH or BuOH for several hours. This unusual reaction pattern was observed for pyrazine-2,3-dicarbonitriles (2) with morpholine, thiomorpholine, piperidine or pyrrolidine substituted in the 5- and 6-positions.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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Epoxy compounds usually have stronger nucleophilic ability, because the alkyl group on the oxygen atom makes the bond angle smaller, which makes the lone pair of electrons react more dissimilarly with the electron-deficient system. Compound: cis-4-Aminocyclohexane carboxylic acid, is researched, Molecular C7H13NO2, CAS is 3685-23-2, about Effects of Atractylodes Oil on Inflammatory Response and Serum Metabolites in Adjuvant Arthritis Rats.Application of 3685-23-2.

Atractylodes Rhizoma is one of two principal components in Ermiaosan, a well-known traditional Chinese medicine for the treatment of rheumatoid arthritis (RA). Atractylodes oil (AO) represents a potential alternative treatment for RA. The purpose of this study was to investigate the effect of AO in rats with Adjuvant Arthritis (AA) by exploration of changes in serum metabolites using gas chromatog.-mass spectrometry (GC-MS). Foot thickness and arthritis score, ankle joint pathol. structure, the concentrations of TNF-α, IL-1β, IL-6, IL-17 and the expression of MMPs in ankle joint tissue were measured as indicators of efficacy of treatment using AO. In addition, multivariate statistical anal. was used to identify differential production of metabolites and biomarkers, and to analyze metabolic pathways. The results demonstrate that administration of AO resulted in a good therapeutic effect in the AA rat model, with significantly improved joint swelling, reduced joint score, and inhibition of inflammation, synovial pannus hyperplasia, and bone and cartilage destruction. Furthermore, AO was found to exert its effect against rheumatoid arthritis principally by differentially affecting 11 metabolites and six metabolic pathways, predominantly related to abnormal amino acid metabolism, in addition to energy-related metabolic pathways. This study evaluated the capability of AO to effectively treat AA rats, providing a novel strategy for the treatment of RA.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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In general, if the atoms that make up the ring contain heteroatoms, such rings become heterocycles, and organic compounds containing heterocycles are called heterocyclic compounds. An article called Synthesis of mono-, di-, tri- and tetracarboxy azaphthalocyanines as potential dark quenchers, published in 2011, which mentions a compound: 56413-95-7, Name is 5,6-Dichloropyrazine-2,3-dicarbonitrile, Molecular C6Cl2N4, Formula: C6Cl2N4.

Mono-, di-, tri- and tetracarboxy-substituted metal-free azaphthalocyanines (AzaPc) were synthesized from 5,6-bis(diethylamino)pyrazine-2,3-dicarbonitrile and 6-(5,6-dicyano-3-(diethylamino)pyrazin-2-ylamino)hexanoic acid using a statistical condensation approach. AzaPc bearing eight diethylamino peripheral substituents was also isolated from the mixture Anal. of the distribution of congeners in the statistical mixture using optimized HPLC method (Phenomenex Synergy RP Fusion column, acetonitrile/tetrahydrofuran/water (pH 5.5) 50:20:30) was performed. The anal. showed optimal ratios of starting materials to be 3:1 for AAAB, 1:3 for ABBB and 1:1 for AABB/ABAB types of the congeners. The distribution of the congeners corresponded well with calculated values indicating similar reactivity of both starting materials and no steric constraint between adjacent isoindole units in the AzaPc ring. All studied AzaPc showed no fluorescence, extremely low singlet oxygen quantum yields (Φ Δ < 0.005) in monomeric form and strong absorption in a wide range from 300 nm to almost 700 nm. Such properties are highly promising for future study of these compounds as dark quenchers of fluorescence in DNA hybridization probes. In addition to the literature in the link below, there is a lot of literature about this compound(5,6-Dichloropyrazine-2,3-dicarbonitrile)Formula: C6Cl2N4, illustrating the importance and wide applicability of this compound(56413-95-7).

Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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Category: chiral-oxygen-ligands. Aromatic compounds can be divided into two categories: single heterocycles and fused heterocycles. Compound: cis-4-Aminocyclohexane carboxylic acid, is researched, Molecular C7H13NO2, CAS is 3685-23-2, about Liquid-phase hydrogenation of some aromatic acids on ruthenium catalysts. Author is Ponomarev, A. A.; Ryzhenko, L. M.; Smirnova, N. S..

Using 10% RuO2 or Ru on activated the hydrogenation was carried out at 100-20° in H2O or in aqueous alk. solutions The following compounds gave 60-99% yields of the following products (starting compound and product given): p-H2NC6H4CO2H, p-aminohexa-hydrobenzoic acid (I); p-O2NC6H4CO2H, I; m-H2NC6H4CO2H, m-aminohexahydrobenzoic acid (II), m-O2NC6H4CO2H, II; m-NaOC6H4CO2Na, m-hydroxyhexahydrobenzoic acid; disodium 2-methylterephthalate, 2-methylhexahydroterephthalic acid.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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The preparation of ester heterocycles mostly uses heteroatoms as nucleophilic sites, which are achieved by intramolecular substitution or addition reactions. Compound: 3-Methyl-1H-pyrrole( cas:616-43-3 ) is researched.Synthetic Route of C5H7N.Wei, Binqing Q.; Baase, Walter A.; Weaver, Larry H.; Matthews, Brian W.; Shoichet, Brian K. published the article 《A Model Binding Site for Testing Scoring Functions in Molecular Docking》 about this compound( cas:616-43-3 ) in Journal of Molecular Biology. Keywords: active site lysozyme binding ligand electrostatic force mol modeling. Let’s learn more about this compound (cas:616-43-3).

Prediction of interaction energies between ligands and their receptors remains a major challenge for structure-based inhibitor discovery. Much effort has been devoted to developing scoring schemes that can successfully rank the affinities of a diverse set of possible ligands to a binding site for which the structure is known. To test these scoring functions, well-characterized exptl. systems can be very useful. Here, mutation-created binding sites in T4 lysozyme were used to investigate how the quality of at. charges and solvation energies affects mol. docking. At. charges and solvation energies were calculated for 172,118 mols. in the Available Chems. Directory using a semi-empirical quantum mech. approach by the program AMSOL. The database was first screened against the apolar cavity site created by the mutation Leu99Ala (L99A). Compared to the electronegativity-based charges that are widely used, the new charges and desolvation energies improved ranking of known apolar ligands, and better distinguished them from more polar isosteres that are not observed to bind. To investigate whether the new charges had predictive value, the non-polar residue Met102, which forms part of the binding site, was changed to the polar residue glutamine. The structure of the resulting Leu99 Ala and Met102 Gln double mutant of T4 lysozyme (L99A/M102Q) was determined and the docking calculation was repeated for the new site. Seven representative polar mols. that preferentially docked to the polar vs. the apolar binding site were tested exptl. All seven bind to the polar cavity (L99A/M102Q) but do not detectably bind to the apolar cavity (L99A). Five ligand-bound structures of L99A/M102Q were determined by X-ray crystallog. Docking predictions corresponded to the crystallog. results to within 0.4 A RMSD. Improved treatment of partial at. charges and desolvation energies in database docking appears feasible and leads to better distinction of true ligands. Simple model binding sites, such as L99A and its more polar variants, may find broad use in the development and testing of docking algorithms.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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Safety of 3-Methyl-1H-pyrrole. The reaction of aromatic heterocyclic molecules with protons is called protonation. Aromatic heterocycles are more basic than benzene due to the participation of heteroatoms. Compound: 3-Methyl-1H-pyrrole, is researched, Molecular C5H7N, CAS is 616-43-3, about Computational Design and Electropolymerization of Molecularly Imprinted Poly(p-Aminobenzoic-Acid-Co-Dapsone) Using Multivariate Optimization for Tetradifon Residue Analysis. Author is Ganjeizadeh Rohani, Fatemeh; Mohadesi, Alireza; Ansari, Mehdi.

In this study, tetradifon as a non-electroactive pesticide was measured by a new gold electrode modified with electropolymerized molecularly imprinted poly(para aminobenzoic acid-co-4,4-diaminodiphenyl sulfone) (P-pABA-co-DDS). The best available monomer was selected based on computational design and then the polymer was developed in optimized condition. Screening of various factors was performed by Plackett-Burman design (PBD) and central composite design (CCD) was utilized to select optimized condition. Under the optimized condition, calibration curve of tetradifon on MIP/gold electrode was constructed with a linear range of 0.05- 2.50μM. The limit of detection (LOD) and limit of quantification (LOQ) was found to be 0.014 and 0.047μM, resp. The developed method showed good stability, repeatability, and reproducibility, sensitivity and selectivity for tetradifon. The developed method was applied to determine tetradifon in real water samples.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate

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So far, in addition to halogen atoms, other non-metallic atoms can become part of the aromatic heterocycle, and the target ring system is still aromatic.Buurman, P.; Nierop, K. G. J.; Kaal, J.; Senesi, N. researched the compound: 3-Methyl-1H-pyrrole( cas:616-43-3 ).Name: 3-Methyl-1H-pyrrole.They published the article 《Analytical pyrolysis and thermally assisted hydrolysis and methylation of EUROSOIL humic acid samples – A key to their source》 about this compound( cas:616-43-3 ) in Geoderma. Keywords: humic acid Eurosoil aliphaticity lignin. We’ll tell you more about this compound (cas:616-43-3).

Humic acids have been widely investigated by spectroscopic methods, especially NMR and FTIR, and they are known to show significant differences according to their origin. Low resolution methods such as NMR and FTIR, however cannot easily distinguish different input sources or establish relations between SOM chem. and vegetation or land use in general. High resolution methods, such as anal. pyrolysis and pyrolysis combined with methylation do offer such possibilities. Therefore, HAs from five reference soils called the Eurosoils, including a Vertic Cambisol (E1, Italy), a Rendzina (E2, Greece), a Dystic Cambisol (E3, Great Britain), an Orthic Luvisol (E4, France) and an Orthic Podzol (E5, Germany), that were previously characterized a.o. by NMR, FTIR and ESR, were also analyzed by pyrolysis-gas chromatog./mass spectrometry (Py-GC/MS) and thermally assisted hydrolysis and methylation (THM) and subsequent anal. by GC/MS. The Orthic Podzol sample showed the largest aliphaticity, and the strongest degradation of aliphatics and lignin. The Dystric Cambisol featured the least decomposed HA, which was reflected by a large content of long-chain alkanes, and little lignin degradation Both the Dystric Cambisol and the Orthic Luvisol HAs contained a significant amount of microbial organic matter. Polyaromatics, which indicate the presence of charred material, were most abundant in the Vertic Cambisol and the Podzol HAs and lowest in the Dystric Cambisol and the Rendzina HAs. THM was able to distinguish between the various vegetations/land uses. Although quantifications by NMR and py-GC/MS are essentially different, the general results largely coincided. NMR appears to underestimate aromaticity and overestimate aliphaticity, but a mol. mixing model yielded reasonable correlations between NMR and pyrolysis data. Classification by degradation state’ based on py-GC/MS largely coincided with acidity determined by titration, but FTIR data did not coincide. Py-GC/MS, with its much larger resolution, is a better tool to distinguish effects of vegetation, microbial input, and degradation HA’s produce the same variety of compounds upon pyrolysis as total SOM extracts and are therefore chem. not more simple than SOM. HA chem., however can be understood in the light of land use history and SOM dynamics.

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Reference:
Synthesis and Crystal Structure of a Chiral C3-Symmetric Oxygen Tripodal Ligand and Its Applications to Asymmetric Catalysis,
Chiral lanthanide(III) complexes of sulphur–nitrogen–oxygen ligand derived from aminothiourea and sodium D-camphor-β-sulfonate