Month: December 2022

Evans, Jeffrey C. published the artcileAn electron spin resonance, ENDOR, and TRIPLE resonance study of methyl-substituted N,N’-diphenyl-4,4′-bipyridylium dichloride radical cations, COA of Formula: C22H18Cl2N2, the publication is Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) (1985), 315-18, database is CAplus.

The ESR and ENDOR spectra of the radical cations of the bipyridylium dichlorides I (R = H, Me, R¹ = R² = R³ = H; R = R² = R³ = H, R¹ = Me; R = R¹ = R³ = H, R² = Me; R = R² = R³ = Me, R¹ = H) (II–VI, resp.) in MeOH were studied over a range of temperatures Values for the hyperfine coupling constants at -40° are given. The radical cation concentrations of II–V decreased with decreasing temperature, this change being reversible, whereas that of VI did not. The reversible change with temperature is explained in terms of a monomer-dimer equilibrium, and the absence of such an equilibrium for VI is due to lack of planarity of the mol., because of steric hindrance between the Me groups and the pyridyl ortho protons. The thermodn. constants ΔG°, ΔH°, and ΔS°, obtained for the dimerization equilibrium, are reported.

Journal of the Chemical Society, Perkin Transactions 2: Physical Organic Chemistry (1972-1999) published new progress about 47369-00-6. 47369-00-6 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Benzene,Organic ligands for MOF materials,Nitrogen containing MOF ligands,Nitrogen containing MOF ligands, name is 1,1′-Diphenyl-[4,4′-bipyridine]-1,1′-diium chloride, and the molecular formula is C22H18Cl2N2, COA of Formula: C22H18Cl2N2.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Grases, F. published the artcileA kinetic fluorimetric method for determination of microamounts of platinum(IV) with 2,2′-dipyridyl ketone hydrazone, SDS of cas: 2215-33-0, the publication is Analytical Letters (1980), 13(A3), 181-9, database is CAplus.

A kinetic method for determination of traces of Pt(IV) is based on the autoxidation of the hydrazone of 2,2′-dipyridyl ketone, in which a fluorescent product (λ_ex 359 nm, λ_em = 435 nm) is formed. The reaction is followed by the measurement of the rate of appearance of the fluorescence. The proposed method suffers very few interferences.

Analytical Letters published new progress about 2215-33-0. 2215-33-0 belongs to pyridine-derivatives, auxiliary class Pyridine,Amine, name is 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, and the molecular formula is C11H10N4, SDS of cas: 2215-33-0.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Regueiro-Figueroa, Martin published the artcileUnderstanding Stability Trends along the Lanthanide Series, Application of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, the publication is Chemistry – A European Journal (2014), 20(14), 3974-3981, database is CAplus and MEDLINE.

The stability trends across the lanthanide series of complexes with the polyaminocarboxylate ligands TETA^4- (H₄TETA = 2,2′,2”,2”’-(1,4,8,11-tetraazacyclotetradecane-1,4,8,11-tetrayl)tetraacetic acid), BCAED^4- (H₄BCAED = 2,2′,2”,2”’-{[(1,4-diazepane-1,4-diyl)bis(ethane-2,1-diyl)]bis(azanetriyl)}tetraacetic acid), and BP18C6^2- (H₂BP18C6 = 6,6′-[(1,4,10,13-tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene)]dipicolinic acid) were investigated using DFT calculations Geometry optimizations performed at the TPSSh/6-31G(d,p) level, and using a 46 + 4fⁿ ECP for lanthanides, provide bond lengths of the metal coordination environments in good agreement with the exptl. values observed in the X-ray structures. The contractions of the Ln³⁺ coordination spheres follow quadratic trends, as observed previously for different isostructural series of complexes. We show here that the parameters obtained from the quant. anal. of these data can be used to rationalize the observed stability trends across the 4f period. The stability trends along the lanthanide series were also evaluated by calculating the free energy for the reaction [La(L)]^n+/-_(sol) + Ln³⁺_(sol)→[Ln(L)]^n+/-_(sol) + La³⁺_(sol). A parameterization of the Ln³⁺ radii was performed by minimizing the differences between exptl. and calculated standard hydration free energies. The calculated stability trends are in good agreement with the exptl. stability constants, which increase markedly across the series for BCAED^4- complexes, increase smoothly for the TETA^4- analogs, and decrease in the case of BP18C6^2- complexes. The resulting stability trend is the result of a subtle balance between the increased binding energies of the ligand across the lanthanide series, which contribute to an increasing complex stability, and the increase in the absolute values of hydration energies along the 4f period.

Chemistry – A European Journal published new progress about 1128304-86-8. 1128304-86-8 belongs to pyridine-derivatives, auxiliary class Pyridines, name is 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, and the molecular formula is C26H36N4O8, Application of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Ferreiros-Martinez, Raquel published the artcileMacrocyclic receptor showing extremely high Sr(II)/Ca(II) and Pb(II)/Ca(II) selectivities with potential application in chelation treatment of metal intoxication, Safety of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, the publication is Inorganic Chemistry (2011), 50(8), 3772-3784, database is CAplus and MEDLINE.

Herein the authors report a detailed study of the complexation properties of the macrocyclic decadentate receptor N,N’-Bis[(6-carboxy-2-pyridyl)methyl]-4,13-diaza-18-crown-6 (H₂bp18c6) toward different divalent metal ions [Zn(II), Cd(II), Pb(II), Sr(II), and Ca(II)] in aqueous solution This ligand is especially suited for the complexation of large metal ions such as Sr(II) and Pb(II), which results in very high Pb(II)/Ca(II) and Pb(II)/Zn(II) selectivities (in fact, higher than those found for ligands widely used for the treatment of lead poisoning such as EDTA), as well as in the highest Sr(II)/Ca(II) selectivity reported so far. These results were rationalized from the structure of the complexes. X-ray crystal diffraction, ¹H and ¹³C NMR spectroscopy, as well as theor. calculations at the d. functional theory (B3LYP) level were performed. The authors’ results indicate that for large metal ions such as Pb(II) and Sr(II) the most stable conformation is Δ(δλδ)(δλδ), while for Ca(II) the authors’ calculations predict the Δ(λδλ)(λδλ) form being the most stable one. The selectivity that bp18c6^2- shows for Sr(II) over Ca(II) can be attributed to a better fit between the large Sr(II) ions and the relatively large crown fragment of the ligand. The x-ray crystal structure of the Pb(II) complex shows that the Δ(δλδ)(δλδ) conformation observed in solution is also maintained in the solid state. The Pb(II) ion is endocyclically coordinated, being directly bound to the 10 donor atoms of the ligand. The bond distances to the donor atoms of the pendant arms (2.55-2.60 Å) are substantially shorter than those between the metal ion and the donor atoms of the crown moiety (2.92-3.04 Å). This is a typical situation observed for the so-called hemidirected compounds, in which the Pb(II) lone pair is stereochem. active. The x-ray structures of the Zn(II) and Cd(II) complexes show that these metal ions are exocyclically coordinated by the ligand, which explains the high Pb(II)/Cd(II) and Pb(II)/Zn(II) selectivities. The authors’ receptor bp18c6^2- shows promise for application in chelation treatment of metal intoxication by Pb(II) and ⁹⁰Sr(II).

Inorganic Chemistry published new progress about 1128304-86-8. 1128304-86-8 belongs to pyridine-derivatives, auxiliary class Pyridines, name is 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, and the molecular formula is C26H36N4O8, Safety of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Shalgunov, Vladimir published the artcileRadiolabeling of a polypeptide polymer for intratumoral delivery of alpha-particle emitter, ²²⁵Ac, and beta-particle emitter, ¹⁷⁷Lu, Safety of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, the publication is Nuclear Medicine and Biology (2022), 11-21, database is CAplus and MEDLINE.

Radiotherapy of cancer requires both alpha- and beta-particle emitting radionuclides, as these radionuclide types are efficient at destroying different types of tumors. Both classes of radionuclides require a vehicle, such as an antibody or a polymer, to be delivered and retained within the tumor. Polyglutamic acid (pGlu) is a polymer that has proven itself effective as a basis of drug-polymer conjugates in the clinic, while its derivatives have been used for pretargeted tumor imaging in a research setup. trans-Cyclooctene (TCO) modified pGlu is suitable for pretargeted imaging or therapy, as well as for intratumoral radionuclide therapy. In all cases, it becomes indirectly radiolabeled via the bioorthogonal click reaction with the tetrazine (Tz) mol. carrying the radionuclide. In this study, we report the radiolabeling of TCO-modified pGlu with either lutetium-177 (¹⁷⁷Lu), a beta-particle emitter, or actinium-225 (²²⁵Ac), an alpha-particle emitter, using the click reaction between TCO and Tz. A panel of Tz derivatives containing a metal ion binding chelator (DOTA or macropa) connected to the Tz moiety directly or through a polyethylene glycol (PEG) linker was synthesized and tested for their ability to chelate ¹⁷⁷Lu and ²²⁵Ac, and click to pGlu-TCO. Radiolabeled ¹⁷⁷Lu-pGlu and ²²⁵Ac-pGlu were isolated by size exclusion chromatog. The retention of ¹⁷⁷Lu or ²²⁵Ac by the obtained conjugates was investigated in vitro in human serum. All DOTA-modified Tzs efficiently chelated ¹⁷⁷Lu resulting in average radiochem. conversions (RCC) of >75. Isolated radiochem. yields (RCY) for ¹⁷⁷Lu-pGlu prepared from ¹⁷⁷Lu-Tzs ranged from 31to 55. TLC analyses detected <5unchelated ¹⁷⁷Lu for all ¹⁷⁷Lu-pGlu preparations over six days in human serum. For ²²⁵Ac chelation, optimized RCCs ranged from 61 ± 34to quant. for DOTA-Tzs and were quant. for the macropa-modified Tz (>98). Isolated radiochem. yields (RCY) for ²²⁵Ac-pGlu prepared from ²²⁵Ac-Tzs ranged from 28to 51. For 3 out of 5 ²²⁵Ac-pGlu conjugates prepared from DOTA-Tzs, the amount of unchelated ²²⁵Ac stayed below 10over six days in human serum, while ²²⁵Ac-pGlu prepared from macropa-Tz showed a steady release of up to 37²²⁵Ac. We labeled TCO-modified pGlu polymers with alpha- and beta-emitting radionuclides in acceptable RCYs. All ¹⁷⁷Lu-pGlu preparations and some ²²⁵Ac-pGlu preparations showed excellent stability in human plasma. Our work shows the potential of pGlu as a vehicle for alpha- and beta-radiotherapy of tumors and demonstrated the usefulness of Tz ligation for indirect radiolabeling.

Nuclear Medicine and Biology published new progress about 1128304-86-8. 1128304-86-8 belongs to pyridine-derivatives, auxiliary class Pyridines, name is 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid, and the molecular formula is C18H12FN, Safety of 6,6′-((1,4,10,13-Tetraoxa-7,16-diazacyclooctadecane-7,16-diyl)bis(methylene))dipicolinic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Pelczar, Elizabeth M. published the artcileUnusual Structural and Spectroscopic Features of Some PNP-Pincer Complexes of Iron, Category: pyridine-derivatives, the publication is Organometallics (2008), 27(22), 5759-5767, database is CAplus.

The authors report a structural, spectroscopic, and computational study of two ^tBuPNP (2,6-bis(di-tert-butyl-phosphinomethyl)pyridine) complexes of iron, (^tBuPNP)FeCl₂ (1) and (^tBuPNP)Fe(CO)₂ (3). Complex 1, (^tBuPNP)FeCl₂, also independently synthesized by Milstein, has unusually long iron-ligand bond distances. DFT calculations show that these are clearly attributable to its high-spin electronic structure, and in particular to occupancy of the strongly antibonding d_x²-y² orbital. The crystal structure of 3 reveals two unusual aspects: the geometry around the iron atom in 3 is much closer to square pyramidal (SQP; apical CO) than to trigonal bipyramidal (TBP), although five-coordinate Fe(0) complexes are generally expected to be TBP; also, Chirik et al. have reported that (^iPrPNP)Fe(CO)₂ has essentially a perfect TBP structure (^iPrPNP = 2,6-bis(di-isopropyl-phosphinomethyl)pyridine); and the apical carbonyl ligand in 3 deviates significantly from linearity (Fe-C-O = 171.9°). Addnl., complex 3 is intensely blue in color, which is unusual for an Fe(0) complex and also significantly different from the red color of Chirik’s (^iPrPNP)Fe(CO)₂ species. Results from DFT calculations reproduce and explain these structural and spectroscopic aspects as well as the contrast between 3 and its ^iPrPNP analog.

Organometallics published new progress about 338800-13-8. 338800-13-8 belongs to pyridine-derivatives, auxiliary class Bis-phosphine Ligands, name is 2,6-Bis((di-tert-butylphosphino)methyl)pyridine, and the molecular formula is C23H43NP2, Category: pyridine-derivatives.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Adel Madbouly, Neveen published the artcileIn vitro and in vivo impacts of nifedipine and diltiazem on praziquantel chemotherapy in murine Schistosoma mansoni, Application of Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, the publication is Experimental Parasitology (2022), 108256, database is CAplus and MEDLINE.

This study was planned to evaluate the in vitro and in vivo antischistosomal effects of the widely used antihypertensive drugs, nifedipine (NIF) and diltiazem (DTZ), and their combinations with praziquantel (PZQ) on early and late Schistosoma (S.) mansoni infections 21- and 45- days old stages. In the In vitro study, Calcium channel blockers (CCBs), NIF and DTZ were added to schistosomula and adult worm cultures in different concentrations 10, 20 and 30 mg/mL. The mortality percentage was calculated 1, 12 and 24 h after incubation. In vivo, NIF and DTZ either alone or combined with PZQ were used to treat male albino mice. The parasitol. and total Ig (Ig) G and IgM anti-soluble egg antigen (SEA) were assessed to demonstrate the disease severity. In the In vitro study, 10 mg/mL NIF induced 100% mortality percentage of both schistosomula and adult worms after 24 h incubation, while DTZ induced similar mortality percentage at 30 mg/mL concentration In vivo results showed that early or late combination of 30 mg/kg of NIF, but not DTZ, significantly (P <0.05) enhanced the reductive efficacy of PZQ based on the parasitol. data. The maximal reduction (P <0.05) of anti-SEA IgM and IgG levels was developed during NIF-PZQ administration 21- (1.12 ± 0.06 and 1.09 ± 0.04, resp.) or 45- (1.00 ± 0.03 and 0.8 ± 0.06, resp.) days post infection (PI), compared to either PZQ or NIF individual treatments. The decreased concentration of anti-SEA antibodies was correlated with the diminished granulomatous diameter and disease severity. Nifedipine improved PZQ chemotherapy targeting either early or late S. mansoni infection in mice compared to the PZQ mono-therapy. Administering NIF can be considered as a promising drug candidate for schistosomiasis chemotherapy.

Experimental Parasitology published new progress about 21829-25-4. 21829-25-4 belongs to pyridine-derivatives, auxiliary class Membrane Transporter/Ion Channel,Calcium Channel, name is Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate, and the molecular formula is C17H18N2O6, Application of Dimethyl 2,6-dimethyl-4-(2-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Al-Janabi, Ahmed S. M. published the artcileSynthesis, anti-bacterial evaluation, DFT study and molecular docking as a potential 3-chymotrypsin-like protease (3CLpro) of SARS-CoV-2 inhibitors of a novel Schiff bases, Formula: C12H9NO, the publication is Journal of Molecular Structure (2021), 129454, database is CAplus and MEDLINE.

New Schiff bases (L¹H) I (I), (L²H) II (II), (L³H) III (III) were synthesized by reaction of 2-benzoylpyridine with different amines (2-amino-6-chlorobenzothiazole, isonicotinohydrazide and N¹-(naphthalen-1-yl)ethane-1,2-diamine) and characterized by ¹H-NMR, ¹³C-NMR, IR mass spectroscopy and elemental anal. The compounds (I), (II) and (III) were assayed by the disk diffusion method for anti-bacterial against five pathogenic bacteria species (Staphylococcus aureus, Micrococcus luteus, Staphylococcus pyogenes, Bacillus subtilis, and E. coli). All prepared Schiff bases (I), (II) and (III) showed good activity compared to pos. control (streptomycin). Moreover the L³H showed the highest activity against S. aureus, and M. luteus than the other compounds and streptomycin. In addnl. mol. docking studies with 3-chymotrypsin-like protease (3CLpro), the essential enzyme for SARS-CoV-2 proliferation. The rest of compounds have shown promising results as 3CLpro inhibitors interacting with the active sites of the enzymes. Finally, DFT’s estimated electrostatic mol. potential results were used to illustrate the mol. docking findings. The DFT calculations showed that L³H has the highest dipole moment and electrophilicity index. Interestingly, L²H of the largest energy gap ΔE = 2.49 eV, there are several hydrophilic interactions that could facilitate the binding with the receptors. All of these parameters could be shared to significantly affect the protein sites of binding affinity with different extent.

Journal of Molecular Structure published new progress about 91-02-1. 91-02-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene,Ketone, name is Phenyl(pyridin-2-yl)methanone, and the molecular formula is C12H9NO, Formula: C12H9NO.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Hughes, Rebecca E. published the artcileMultiparametric High-Content Cell Painting Identifies Copper Ionophores as Selective Modulators of Esophageal Cancer Phenotypes, Synthetic Route of 54856-23-4, the publication is ACS Chemical Biology (2022), 17(7), 1876-1889, database is CAplus and MEDLINE.

Esophageal adenocarcinoma is of increasing global concern due to increasing incidence, a lack of effective treatments, and poor prognosis. Therapeutic target discovery and clin. trials have been hindered by the heterogeneity of the disease, the lack of “druggable” driver mutations, and the dominance of large-scale genomic rearrangements. We have previously undertaken a comprehensive small-mol. phenotypic screen using the high-content Cell Painting assay to quantify the morphol. response to a total of 19,555 small mols. across a panel of genetically distinct human esophageal cell lines to identify new therapeutic targets and small mols. for the treatment of esophageal adenocarcinoma. In this current study, we report for the first time the dose-response validation studies for the 72 screening hits from the target-annotated LOPAC and Prestwick FDA-approved compound libraries and the full list of 51 validated esophageal adenocarcinoma-selective small mols. (71% validation rate). We then focus on the most potent and selective hit mols., elesclomol, disulfiram, and ammonium pyrrolidinedithiocarbamate. Using a multipronged, multitechnol. approach, we uncover a unified mechanism of action and a vulnerability in esophageal adenocarcinoma toward copper-dependent cell death that could be targeted in the future.

ACS Chemical Biology published new progress about 54856-23-4. 54856-23-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Salt,Amine,Inhibitor,Inhibitor, name is N-Methyl-2-(pyridin-2-yl)ethan-1-amine dimethanesulfonate, and the molecular formula is C10H20N2O6S2, Synthetic Route of 54856-23-4.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem

Al-Sanea, Mohammad M. published the artcileSynthesis and in Vitro Screening of Phenylbipyridinylpyrazole Derivatives as Potential Antiproliferative Agents, Application of (6-Ethoxypyridin-3-yl)boronic acid, the publication is Molecules (2015), 20(1), 1031-1045, 15 pp., database is CAplus and MEDLINE.

A series of phenyl(bipyridinyl)pyrazoles I (R = F, MeS, morpholin-4-yl, etc.) were synthesized and screened at 10 μM against over 60 tumor cell lines at the U.S. National Cancer Institute (NCI). Compounds I [R = pyrrolidin-1-yl, 4-benzylpiperazin-1-yl (II)] showed a broad spectrum of activity against NCI cell lines with mean growth of 53% and 58%, resp. Compound I [R = 4-methylpiperazin-1-yl (III)] behaved differently as it showed a high degree of selectivity and potency by inhibiting 96% of growth of leukemia SR cell line at 10 μM. Standard COMPARE anal. was performed at the GI₅₀ level and the results exhibited a high correlation in the form of pairwise correlation coefficient (PCC) of more than 0.6 between three of the current compounds and three standard known anticancer agents. Compound III demonstrated a high correlation level with merbarone (NSC S336628) with a PCC value of 0.631. Compound II showed a considerably high PCC value of 0.626 with dichloroallyl lawsone, while compound I (R = benzyloxy), showed PCC values of 0.601 and 0.604 with both dichloroallyl lawsone and N,N-dibenzyldaunomycin (NSC S268242), resp. These three standard agents have anticancer activity via two major mechanism of actions, inhibition of topoisomerase II and inhibition of biosynthesis of pyrimidine nucleotides, therefore, compounds I are promising therapeutic agents for targeting different human malignancies. Prediction of drug-likeness and toxicity of the synthesized derivatives I were also considered.

Molecules published new progress about 612845-44-0. 612845-44-0 belongs to pyridine-derivatives, auxiliary class Pyridine,Boronic acid and ester,Ether,Boronic Acids,Boronic acid and ester, name is (6-Ethoxypyridin-3-yl)boronic acid, and the molecular formula is C7H10BNO3, Application of (6-Ethoxypyridin-3-yl)boronic acid.

Referemce:
https://en.wikipedia.org/wiki/Pyridine,
Pyridine | C5H5N – PubChem