Month: December 2022

Kaal, Joeri published the artcileFingerprinting macrophyte Blue Carbon by pyrolysis-GC-compound specific isotope analysis (Py-CSIA), Category: ethers-buliding-blocks, the publication is Science of the Total Environment (2022), 155598, database is CAplus and MEDLINE.

There is a need for tools to determine the origin of organic matter (OM) in Blue Carbon Ecosystems (BCE) and marine sediments to (1) facilitate the implementation of Blue Carbon strategies into carbon accounting and crediting schemes and (2) decipher changes in ecosystem condition over decadal to millennial time scales and thus to understand and predict the stability of BCE in a changing world. Pyrolysis-GC-compound specific isotope anal. (Py-CSIA) is applied for the first time in marine environments and BCE research. We studied Australian mangrove, tidal marsh and seagrass sediments, in addition to potential sources of OM (Avicennia, Posidonia, Zostera, Sarcocornia, Ecklonia and Ulva species and seagrass epiphytes), to identify precursors of different biomacromol. constituents (lignin, polysaccharides and aliphatic structures). Firstly, the link between bulk δ¹³C and δ¹³C reconstructed from compound-specific δ¹³C showed that the pyrolysis approach allows for the isotopic screening of a representative portion of the OM. Secondly, for all samples, the C isotope fingerprint of the carbohydrate products (plant polysaccharides) was the heaviest (¹³C enriched), followed by lignin and aliphatic products. The differences in δ¹³C among macromols. and the overlap in δ¹³C among putative sources reflect the limitations of bulk δ¹³C analyses for deciphering OM provenance. Thirdly, phanerogams specimen had the heaviest carbohydrate and lignin, confirming that seagrass-derived lignocellulose can be traced based on δ13C. Consistent differences for individual compounds were identified between seagrasses and between Avicennia and Sarcocornia using Py-CSIA. Fourth, ecosystem shifts (colonization of seagrass habitats by mangrove) on millenary time scales, hypothesized in previous studies on the basis of bulk δ13C and Py-GC-MS, were confirmed by Py-CSIA. We conclude that Py-CSIA is useful in Blue Carbon research to decipher OM sources in marine sediments, identify ecosystem transitions in palaeoenvironmental records, and to understand the role of different OM compounds in Blue Carbon storage.

Science of the Total Environment published new progress about 134-96-3. 134-96-3 belongs to ethers-buliding-blocks, auxiliary class Immunology/Inflammation,COX,Natural product, name is 4-Hydroxy-3,5-dimethoxybenzaldehyde, and the molecular formula is C9H10O4, Category: ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Vasiliev, A. D. published the artcileCrystal structure of bis(α,α’-dithio-bis(formamidinium)) bis(μ₂-chloro)hexachlorodimercurate(II), SDS of cas: 14807-75-1, the publication is Russian Journal of Inorganic Chemistry (2013), 58(11), 1298-1301, database is CAplus.

The crystal and mol. structure of bis(α,α’-dithio-bis(formamidinium)) bis(μ₂-chloro)hexachlorodimercurate(II) C₄H₁₆Hg₂Cl₈N₈S₄ (I), where α,α’-dithio-bis(formamidine) is C₂H₆N₄S₂, was solved. Crystals are monoclinic, a 8.6417(6), b 14.648(1), c 10.2111(8) Å, β 104.949(1)°, V = 1248.8(2) ų, space group P2₁/n, Z = 4. The crystal structure is built of HgCl₄^2- ions linked via inversion centers into [Hg₂Cl₈]^4- pairs and C₂H₈N₄S₂²⁺ cations. [Hg₂Cl₈]^4- anions and C₂H₈N₄S₂²⁺ cations form alternating layers linked by N-H^…Cl H bonds into a framework structure.

Russian Journal of Inorganic Chemistry published new progress about 14807-75-1. 14807-75-1 belongs to ethers-buliding-blocks, auxiliary class Salt,Thiourea,Amine,Aliphatic hydrocarbon chain, name is Formamidine disulfide dihydrochloride, and the molecular formula is C18H24N6O6S4, SDS of cas: 14807-75-1.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Koparan, Arzu published the artcileA Validated Method for Separation and Determination of Codeine Phosphate Hemihydrate Impurities in Bilayer Tablet Dosage Form of Naproxen Sodium and Codeine Phosphate by Using UHPLC, Safety of 2-Methoxynaphthalene, the publication is Current Pharmaceutical Analysis (2021), 17(6), 748-760, database is CAplus.

Apranax Plus is a new bilayer tablet dosage form, which combines two active pharmaceutical ingredients: naproxen sodium and codeine phosphate. The purpose of this work was to develop an Ultra-High-Performance Liquid Chromatog. (UHPLC) method for the separation and determination of codeine phosphate hemihydrate impurities in a bilayer tablet dosage form. The separation and determination of codeine phosphate hemihydrate and its impurities, methylcodeine, morphine, codeine dimer, 10-hydroxycodeine, 14-hydroxycodeine, thebaine and codeinone were achieved by using reversed-phase liquid chromatog. with TUV (Tunable UV Detector) and PDA (Photodiode Array Detector) detection by UHPLC. The new proposed method utilized by the Waters Acquity UHPLC TUV and PDA systems using a UHPLC column Waters Acquity, BEH, C18, 2.1×100 mm, 1.7μm particle size with a mixture of component A and acetonitrile in a gradient mode at a flow rate of 0.3mL/min, at 25°C with a load of 5μL. The detection for all eluted compounds was carried out at 245nm. The codeine phosphate hemihydrate and peaks of its impurities were adequately obtained, thus proving the stability-indicating power of the method. The developed method was validated as per the ICH guidelines with respect to parameters such as precision, accuracy, linearity, Limit of Detection (LOD), Limit of Quantification (LOQ) and robustness. It was verified as being adequate for all the mentioned impurities of codeine phosphate hemihydrate. The described method was found to be useful for routine purity testing and was also found suitable for the anal. of the stability samples of the drug product.

Current Pharmaceutical Analysis published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C11H10O, Safety of 2-Methoxynaphthalene.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Haas, Brittany C. published the artcilePredicting relative efficiency of amide bond formation using multivariate linear regression, Safety of (2-Methoxyphenyl)methanamine, the publication is Proceedings of the National Academy of Sciences of the United States of America (2022), 119(16), e2118451119, database is CAplus and MEDLINE.

Herein, the development of statistical models correlating measured rates to phys. organic descriptors to enable the prediction of reaction rates for untested carboxylic acid/amine pairs was reported. The key to the success of this endeavor was the development of an end-to-end data science-based work flow to select a set of coupling partners that were appropriately distributed in chem. space to facilitate statistical model development. By using a parameterization, dimensionality reduction, and clustering protocol, a training set was identified. Reaction rates for a range of carboxylic acid and primary alkyl amine couplings utilizing carbonyldiimidazole (CDI) as the coupling reagent were measured. The collected rates span five orders of magnitude, confirming that the designed training set encompasses a wide range of chem. space necessary for effective model development. Regressing these rates with high-level d. functional theory (DFT) descriptors allowed for identification of a statistical model wherein the mol. features of the carboxylic acid are primarily responsible for the observed rates. Finally, out-of-sample amide couplings are used to determine the limitations and effectiveness of the model.

Proceedings of the National Academy of Sciences of the United States of America published new progress about 6850-57-3. 6850-57-3 belongs to ethers-buliding-blocks, auxiliary class Amine,Benzene,Ether, name is (2-Methoxyphenyl)methanamine, and the molecular formula is C8H11NO, Safety of (2-Methoxyphenyl)methanamine.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Murthy, A. V. R. published the artcileProbing the Role of Chain Length on the Diffusion Dynamics of π-Conjugated Polymers by Fluorescence Correlation Spectroscopy, Application In Synthesis of 146370-51-6, the publication is Journal of Physical Chemistry B (2011), 115(37), 10779-10788, database is CAplus and MEDLINE.

We investigate the role of the chain length and mol. weight distribution on the diffusion dynamics of freshly synthesized MEH-PPV polymer chains. For the above purpose, a new technique based on combination of size exclusion chromatog. (SEC) with fluorescence correlation spectroscopy (FCS) is developed to probe the diffusion dynamics of a narrow mol. weight distribution of fractionated samples of 20-500 kDa. The narrow dispersed samples were characterized by absorbance, emission, and time-resolved fluorescence decay techniques. The results revealed that the properties of fractionated samples were almost uniform for a wide range of mol. weights A maximum entropy based method for FCS data anal. is employed to obtain the correct diffusion coefficients of the polymer chains with heterogeneous dynamics. The FCS experiment on the unfractionated broad mol. weight sample is not enough to establish the correlation between the mol. weight of the chains with diffusion dynamics and emphasized the need for relatively monodispersed π-conjugated polymers. FCS results show that higher mol. weight chains diffuse much faster than shorter ones. Atomic force microscopy revealed that 300 kDa polymers produced 130 nm particles, whereas 50 kDa polymer chains formed micrometer size aggregates. At higher mol. weights, the strong chain interactions promote the formation of globular (or tightly packed) particles which diffuse faster in solution The low mol. weight chains experience strong interparticle interaction; as a consequence, the diffusion of chains becomes slower. In the present investigation, we demonstrate the need for the narrow polydisperse sample for establishing the correlation between diffusion dynamics and chain length (or mol. weights) of π-conjugated polymers using a single mol. spectroscopy technique such as FCS.

Journal of Physical Chemistry B published new progress about 146370-51-6. 146370-51-6 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether, name is 1-((2-Ethylhexyl)oxy)-4-methoxybenzene, and the molecular formula is C15H24O2, Application In Synthesis of 146370-51-6.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Beyer, H. published the artcileThe formation of bisformamidine sulfides and isoureas, Category: ethers-buliding-blocks, the publication is Journal fuer Praktische Chemie (Leipzig) (1963), 20(5-6), 263-74, database is CAplus.

cf. CA 58, 2388d. RNHCSNH₂ (0.02 mole) and 0.01 mole R’₂NCN disolved in 15 ml. 5.6% absolute alc. HCl gave S[C(:NH)NHR]₂.2HCl (I) (all m.ps. with decomposition). In this way, SC(NH₂)₂ (II) with Et₂NCN (III), (CH₂:CHCH₂)₂NCN (IV), Bu₂NCN (V), PhNHCN, o-ClC₆H₄NHCN, p-MeC₆H₄NHCN, or BzNHCN (VI) gave 79, 85, 85, 47, 79, 52, or 74% I (R = H), m. 180°; MeNHCSNH₂ with III, IV, V, or MeNHCN gave 90, 90, 95, or 94% l (R = Me), m. 161°; EtNHCSNH₂ with III, IV, V, VI, or EtNHCN gave 57, 60, 69, 71, or 82% I (R = Et), m. 163°; CH₂:CHCH₂NHCSNH₂ with IV gave 55% I (R = CH₂:CHCH₂), m. 136-7°; PrNHCSNH₂ with IV gave 51% I (R = Pr), m. 156-7°; BuNHCSNH₂ with V gave 60% I (R = Bu), m. 147°; MeEtCHNHSNH₂ with IV or V gave 90% l (R = MeEtCH), m. 160-2°; PhCH₂NHCSNH₂ with IV, V, or PhCH₂NHCN gave 51, 54, or 81% I (R = PhCH₂), m. 179-81°; and PhCH₂CH₂NHCSNH₂ with IV or V gave 80 or 83% I (R = PhCH₂CH₂), m. 162-3°. (PhNH)₂CS and III in 15 ml. 5.6% alc. HCl gave 22% [PhNH(PhN:)Cl₂S.HCl, m. 248-51°; PhNHCSNH₂ and PhNHCN in 7.5 ml. 5.5% alc. HCl gave 72% [PhNH(HN:)Cl₂S.HCl, m. 147°; Et₂NCSNH₂ and III 4-5 weeks in alc. HCl gave 45% [Et₂N(HN:)Cl₂S.HCl, m. 139-40°. From the mother liquors of I from II with III, IV, or V, 31% Et₂NCSNH₂, m. 101-2°, 38% (CH₂:CHCH₂)₂NCSNH₂, or 38% Bu₂NCSNH₂, m. 58-9°, was isolated. Treating 0.02 mole VI with 0.02 mole PrOH, BuOH, MeEtCHOH, AmOH, or iso-AmOH (all containing HCl) gave 62% BzNHC(:NH)OR.HCl (VII) (R = Pr). m. 97° (free base m. 45°; picrate m. 140°], 86% VII (R = Bu) (VIII), m. 80° (free base 42°; yellow picrate m. 130-1°), 55% VII (R = MeEtCH) (IX), m. 104° (free base m. 54°; yellow picrate m. 136°), 83% VII (R = Am), m. 75° (free base m. 54°; picrate m. 131°), or 81% VII (R = iso-Am), m. 64° (yellow picrate m. 133°). Keeping a solution of 1.5 g. VI overnight in 15 ml. absolute alc. HCl gave 80% BzNHCONH₂ (X), m. 215°. Passing HCl gas into an equimol. mixture of p-MeC₆H₄CONHCN and PrOH and keeping overnight yielded 78% p-MeC₆H₁CONHCONH₂, m. 232°, and 51% PrCl. Heating 2.2 g. IX in 10 ml. 8.2% HBr in dioxane gave 91% BzNHCONH₂ and MetEtCHBr, identified via the S-isobutylisothiuronium picrate, m. 167°. Refluxing 11 g. VIII with AcOH gave 48% AcOBu, b. 125-6°. H₂NCN and Et₂NCONH₂ did not reach in the presence of HCl. VII also were split by HBr and HI, giving the corresponding alkyl halides.

Journal fuer Praktische Chemie (Leipzig) published new progress about 14807-75-1. 14807-75-1 belongs to ethers-buliding-blocks, auxiliary class Salt,Thiourea,Amine,Aliphatic hydrocarbon chain, name is Formamidine disulfide dihydrochloride, and the molecular formula is C2H8Cl2N4S2, Category: ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Montone, Carmela Maria published the artcileUntargeted analysis of contaminants in river water samples: Comparison between two different sorbents for solid-phase extraction followed by liquid chromatography-high-resolution mass spectrometry determination, SDS of cas: 91-16-7, the publication is Microchemical Journal (2022), 172(Part_A), 106979, database is CAplus.

In this work, an untargeted approach based on ultra-high performance liquid chromatog. coupled to high-resolution tandem mass spectrometry (UHPLC-HRMS/MS) was employed for the anal. of contaminants in surface water samples, possibly deriving from an ineffective removal by wastewater treatment plants or illicit release. First, solid-phase extraction (SPE) conditions for 30 target compounds were optimized for two different sorbents, namely the com. Oasis HLB and graphitized carbon black (GCB), by Box-Behnken designs of experiments Upon identification of optimal conditions, the two SPE materials yielded comparable extraction recoveries, ranging between 52 and 110% and 55-100% for Oasis HLB and GCB, resp. Thereafter, river water samples collected in five locations near Rome (Italy) were extracted using both sorbents and then analyzed by UHPLC-HRMS/MS in both pos. and neg. electrospray (ESI) ion polarities. The retrieved raw data files were submitted to Compound Discoverer software and compound identification was tentatively assigned by matching their tandem mass spectra with the mzCloud mass spectral library and manual validation, resulting in a total of 241 identified compounds (211 and 40 in pos. and neg. ESI mode, resp.), mainly belonging to pharmaceuticals.

Microchemical Journal published new progress about 91-16-7. 91-16-7 belongs to ethers-buliding-blocks, auxiliary class Benzene,Ether,Inhibitor,Inhibitor,Inhibitor, name is 1,2-Dimethoxybenzene, and the molecular formula is C8H10O2, SDS of cas: 91-16-7.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Pawar, Gaurav published the artcileCu(I)-Catalyzed Microwave-Assisted Multicomponent Reaction Towards Synthesis of Diverse Fluorescent Quinazolino[4,3-b]quinazolin-8-ones and Their Photophysical Study, Related Products of ethers-buliding-blocks, the publication is ChemistrySelect (2022), 7(14), e202200500, database is CAplus.

A novel, base- and ligand-free one pot protocol for the synthesis of fused-quinazolinone under microwave irradiation using environmentally friendly PEG-400 as a solvent has been developed. Besides benzaldehyde, various benzyl alcs. and Me arenes were used in this protocol, which extend its synthetic applicability. Photophys. study of this highly fluorescent framework was studied by fluorescent study. DFT and ESI/MS studies were carried out to justify the proposed mechanism.

ChemistrySelect published new progress about 134-96-3. 134-96-3 belongs to ethers-buliding-blocks, auxiliary class Immunology/Inflammation,COX,Natural product, name is 4-Hydroxy-3,5-dimethoxybenzaldehyde, and the molecular formula is C9H10O4, Related Products of ethers-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Mueller, Valentin published the artcileC-F Activation for C(sp²)-C(sp³) Cross-Coupling by a Secondary Phosphine Oxide (SPO)-Nickel Complex, Quality Control of 93-04-9, the publication is Organic Letters (2020), 22(17), 7034-7040, database is CAplus and MEDLINE.

A secondary phosphine oxide (SPO)-nickel catalyst allowed the activation of otherwise inert C-F bonds of unactivated arenes in terms of challenging couplings with primary and secondary alkyl Grignard reagents. The C-F activation is characterized by mild reaction conditions and high levels of branched selectivity. Electron-rich and electron-deficient arenes were suitable electrophiles for this transformation. In addition, this strategy also proved suitable to heterocycles and for the activation of C-O bonds under slightly modified conditions.

Organic Letters published new progress about 93-04-9. 93-04-9 belongs to ethers-buliding-blocks, auxiliary class Naphthalene,Ether, name is 2-Methoxynaphthalene, and the molecular formula is C11H10O, Quality Control of 93-04-9.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem

Vezina-Dawod, Simon published the artcileConvenient two-step synthesis of highly functionalized benzo-fused 1,4-diazepin-3-ones and 1,5-diazocin-4-ones by sequential Ugi and intramolecular S_NAr reactions, Application of (S)-2-((((9H-Fluoren-9-yl)methoxy)carbonyl)(methyl)amino)-3-phenylpropanoic acid, the publication is Tetrahedron (2017), 73(44), 6347-6355, database is CAplus.

A rapid and efficient two-step method was reported for synthesis of polysubstituted 1,4-benzodiazepin-3-ones I [R¹ = t-Bu, (CH₂)₅, cyclohexyl, Bn; R² = (CH₂)₃, Bn, Ph, etc.; R³ = H, Me, Bn, etc.; R⁴ = H, Me] and 1,5-benzodiazocin-4-ones II in high yields [R⁵ = H, Ph, 3-methyl-1H-indolyl] using a multicomponent condensation/cyclization. This approach used an Ugi four-component reaction to condense readily available N-Fmoc-amino acids, amines and isocyanides with a 2-fluoro-5-nitrobenzaldehyde to afford Fmoc-protected bis-amide intermediates, e.g., III followed by a one-pot Fmoc-group removal, intramol. aromatic nucleophilic substitution for ring closure and side chain deprotection.

Tetrahedron published new progress about 77128-73-5. 77128-73-5 belongs to ethers-buliding-blocks, auxiliary class Inhibitor, name is (S)-2-((((9H-Fluoren-9-yl)methoxy)carbonyl)(methyl)amino)-3-phenylpropanoic acid, and the molecular formula is C12H16BNO4, Application of (S)-2-((((9H-Fluoren-9-yl)methoxy)carbonyl)(methyl)amino)-3-phenylpropanoic acid.

Referemce:
https://en.wikipedia.org/wiki/Ether,
Ether | (C2H5)2O – PubChem