Tag: M.W=150-200

Ishii, Hajime published the artcileSynthesis of sensitive pyridylhydrazone reagents and extraction-spectrophotometric determination of trace nickel with 2-pyridinecarboxaldehyde 2-(5-nitro)pyridylhydrazone, Name: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, the publication is Analytical Sciences (1987), 3(4), 347-52, database is CAplus.

Three new hydrazones, in which the hydrogen at the 5-position of the pyridine ring in the hydrazine moiety of 2-pyridinecarboxaldehyde 2-pyridylhydrazone was substituted by a Me, chloro, or nitro group, have been synthesized and their chromogenic properties, reactivities with metal ions, and extractabilities of the metal complexes were studied. The acid dissociation constants (K_a) of the synthesized hydrazones were determined spectrophotometrically. These values obeyed Hammett’s law, the inductive effect of the substituents being found to reflect the pK_a values. Of the synthesized hydrazones, 2-pyridinecarboxaldehyde 2-(5-nitro)pyridylhydrazone (PANPH), in which an electron-withdrawing nitro group was introduced, was most sensitive for metal ions. Its copper and nickel complexes showed molar absorptivities of the order of 10⁵. A highly sensitive and selective extraction-spectrophotometric method for the determination of nickel with PANPH is proposed and has been successfully applied to the determination of nickel in steel samples. The method has been further sensitized by employing analog derivative spectrophotometry.

Analytical Sciences 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, Name: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine.

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

Taya, Toshiki published the artcileComplexation behavior of heterocyclic hydrazones. II. Effects of steric factors on formation constants for nickel(II) complexes with heterocyclic hydrazones, Related Products of pyridine-derivatives, the publication is Bulletin of the Chemical Society of Japan (1994), 67(3), 710-19, database is CAplus.

The equilibrium of nickel(II) ion with thirteen nitrogen-heterocyclic hydrazones (neutral form: HL) with and without blocking group(s) have been investigated spectrophotometrically in 28% aqueous dioxane solution at 25°C and an ionic strength of 0.2 (KCl). For a series of 2-pyridinecarbaldehyde 5-substituted-2-pyridylhydrazones, the following linear free energy relationships (LFER) were derived between the overall formation constants, β₁, β₁‘, and β₂, of Ni(HL)²⁺, NiL⁺, and Ni(HL)₂²⁺ complexes, resp., and the dissociation constants, K_a1 and K_a2, of H₃L²⁺ and H₂L⁺, resp.: log β₁ = 0.95 (pK_a1 + pK_a2)/2 + 4.60, 1/2 log β₂ = 0.95 × (pK_a1 + pK_a2)/2 + 4.82, and log β₁‘ = 1.40 (pK_a1 + pK_a2)/2 + 9.73. The steric effects of the 6-Me group in pyridine and the quinolyl ring in place of pyridyl group on the complex formation were evaluated on the basis of LFER. The complex stabilization effect of the pyridyl group substituted for formyl hydrogen was also evaluated for Ni(HL)₂²⁺, Ni(HL)²⁺, and NiL⁺ complexes. These results together with LFER were discussed in conjunction with the thermodn. parameters for the formation of Ni(HL)²⁺ complex and the ligand field parameters, D_q, for Ni(HL)²⁺ and Ni(HL)₂²⁺ complexes.

Bulletin of the Chemical Society of Japan 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 C7H8BBrO3, Related Products of pyridine-derivatives.

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

Prakash, Sekar published the artcileCobalt-Catalyzed Oxidative Annulation of Nitrogen-Containing Arenes with Alkynes: An Atom-Economical Route to Heterocyclic Quaternary Ammonium Salts, Quality Control of 85237-71-4, the publication is Angewandte Chemie, International Edition (2016), 55(5), 1844-1848, database is CAplus and MEDLINE.

Four cobalt-catalyzed oxidative annulation reactions of nitrogen-containing arenes with alkynes proceeds by C-H activation, thus leading to biol. useful quaternary ammonium salts, including pyridoisoquinolinium, cinnolinium, isoquinolinium, and quinolizinium salts, in high yields. The results are comparable to those reactions catalyzed by rhodium and ruthenium complexes. The transformation of the salts into various N-heterocycles has also been demonstrated.

Angewandte Chemie, International Edition published new progress about 85237-71-4. 85237-71-4 belongs to pyridine-derivatives, auxiliary class Pyridine,Benzene, name is 5-Methyl-2-(p-tolyl)pyridine, and the molecular formula is C13H13N, Quality Control of 85237-71-4.

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

Nirmalram, Jeyaraman Selvaraj published the artcileHydrogen-bonding patterns in pyrimethaminium pyridine-3-sulfonate, Recommanded Product: Pyridine-3-sulfonic acid, the publication is Acta Crystallographica, Section E: Structure Reports Online (2010), 66(8), o2121-o2122, database is CAplus and MEDLINE.

In the asym. unit of the title salt [systematic name: 2,4-diamino-5-(4-chlorophenyl)-6-ethylpyrimidin-1-ium pyridine-3-sulfonate], C₁₂H₁₄N₄Cl⁺·C₅H₄NSO₃^–, there are two independent pyrimethaminium cations and two 3-pyridine sulfonate anions. Each sulfonate group interacts with the corresponding protonated pyrimidine ring through two N-H…O hydrogen bonds, forming a cyclic hydrogen-bonded bimol. R₂²(8) motif. Even though the primary mode of association is the same, the next higher level of supramol. architectures are different due to different hydrogen-bonded networks. In one of the independent mols. in the asym. unit, the pyrimethamine cation is paired centrosym. through N-H…N hydrogen bonds, generating an R₂²(8) ring motif. In the other mol., the pyrimethamine cation does not form any base pairs; instead it forms hydrogen bonds with the 3-pyridine sulfonate anion. The structure is further stabilized by C-H…O, C-H…N and π-π stacking [centroid-centroid distance = 3.9465 (13) Å] interactions. Crystallog. data are given.

Acta Crystallographica, Section E: Structure Reports Online published new progress about 636-73-7. 636-73-7 belongs to pyridine-derivatives, auxiliary class Pyridine,Sulfonic acid, name is Pyridine-3-sulfonic acid, and the molecular formula is C5H5NO3S, Recommanded Product: Pyridine-3-sulfonic acid.

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

Hamukwaya, Eunike published the artcileA multi-colorimetric probe to discriminate between heavy metal cations and anions in DMSO-H₂O with high selectivity for Cu²⁺ and CN^–: study of logic functions and its application in real samples, Quality Control of 91-02-1, the publication is RSC Advances (2021), 11(47), 29466-29485, database is CAplus and MEDLINE.

A ditopic multi-colorimetric probe based on the phenylpridyl-thioic moiety (EN) was synthesized via a Schiff base reaction mechanism and characterized using ¹H NMR and UV-vis spectroscopy. The colorimetric analyses carried out revealed that EN was capable of discriminating between a number of heavy metal cations via coordination induced charge transfer, as well as between anions through hydrogen bonding induced charge transfer, in DMSO-H₂O (9 : 1). In particular, the ditopic probe could spectrally and colorimetrically recognize the most toxic heavy metal cations of Cd²⁺, Pb²⁺ and Hg²⁺, among others, in DMSO-H₂O. Addnl., EN was selective and sensitive to the presence of CN^–, F^–, AcO^– and H₂PO₄^– in the same solvent system as cations. The reversibility and reproducibility studies showed that EN exhibited complementary IMP/INH logic functions, based on color and spectral switching (ON/OFF), modulated by F^–/Al³⁺. The real time application of the probe was tested on food grade products to detect the presence of F^– in toothpastes and mouthwash dissolved in water, as well as cations in underground water (normally saline), which displayed substantial responses. Thus, EN displayed an excellent scope of response and can thus be developed for real time sensing kits, which could be used instantly in on-field anal. Theor. studies were conducted to complement the exptl. work.

RSC Advances 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, Quality Control of 91-02-1.

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

Larionov, Evgeny published the artcileScope and mechanism of asymmetric C(sp³)-H/C(Ar)-X coupling reactions: computational and experimental study, Recommanded Product: 2-Bromopyridin-3-amine, the publication is Chemical Science (2013), 4(5), 1995-2005, database is CAplus.

Advances in the efficient palladium-NHC catalyzed synthesis of highly enantioenriched 2,3-trans-fused and 2-alkyl indolines by an asym. C(sp³)-H activation of an unactivated methylene/methyl group are reported. Very high asym. inductions (up to 99% ee) were achieved at reaction temperatures ranging from 120-160°. Factors influencing the efficiency of the reaction (halide, pseudohalide, N-protecting group) were investigated. The reaction pathway and enantioselection were probed by detailed d. functional theory (DFT) calculations (M06-L functional). The combined theor. and exptl. study shows that the Pd-NHC catalyzed C(sp³)-H arylation proceeds via a concerted metalation-deprotonation (CMD) mechanism. The CMD step is shown by DFT calculations and kinetic isotope effect measurements to be selectivity-determining A good agreement between exptl. enantioselectivities and calculated differences amongst diastereomeric activation barriers is observed

Chemical Science published new progress about 39856-58-1. 39856-58-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Bromide,Amine, name is 2-Bromopyridin-3-amine, and the molecular formula is C5H5BrN2, Recommanded Product: 2-Bromopyridin-3-amine.

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

Venkateshwarlu, Rapolu published the artcileUltrasound assisted one-pot synthesis of 1,2-diaryl azaindoles via Pd/C-Cu catalysis: Identification of potential cytotoxic agents, Application of 2-Bromopyridin-3-amine, the publication is Tetrahedron Letters (2019), 60(52), 151326, database is CAplus.

Ultrasound assisted one-pot and direct access to 1,2-diaryl substituted azaindole derivatives I [W = CH, N; X = CH, N; Y = CH, N; Z = CH, N; Ar¹ = Ph, 4-ClC₆H₄, 4-MeC₆H₄; Ar² = 4-CNC₆H₄, 4-MeOC₆H₄, 4-Me(SO₂)C₆H₄, etc.] was achieved via the sequential N-arylation followed by coupling-cyclization under Pd/C-Cu catalysis. The methodol. involved initial C-N bond forming reaction (step 1) between an appropriate o-bromo substituted amino pyridine and iodoarene followed by C-C and C-N bond formation (step 2) between the resulting N-aryl substituted intermediate and a terminal alkyne in the same pot. A variety of azaindoles were prepared by using this method. These compounds were assessed for their cytotoxic properties against two different metastatic breast cancer cell lines e.g. MDA-MB-231 and MCF-7. Compounds I [W = Y = Z = CH, X = N, Ar¹ = 4-MeC₆H₄, Ar² = 4-MeOC₆H₄], I [W = Y = Z = CH, X = N, Ar¹ = Ph, Ar² = 4-MeOC₆H₄] and I [W = Y = Z = CH, X = N, Ar¹ = 4-ClC₆H₄, Ar² = 3,5-di-MeOC₆H₃] showed promising growth inhibition of these cell lines and SIRT1 inhibition in vitro.

Tetrahedron Letters published new progress about 39856-58-1. 39856-58-1 belongs to pyridine-derivatives, auxiliary class Pyridine,Bromide,Amine, name is 2-Bromopyridin-3-amine, and the molecular formula is C15H24O2, Application of 2-Bromopyridin-3-amine.

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

Shapiro, Anna published the artcileIn vivo and in vitro activity by diverse chelators against Trypanosoma brucei brucei, Product Details of C11H10N4, the publication is Journal of Protozoology (1982), 29(1), 85-90, database is CAplus and MEDLINE.

A system of prescreens and a screen was developed to select chelators as potential drugs against T. brucei brucei EATRO 110. The chelators tested were nearly all com. available, low mol., and had a moderate to high affinity for Fe(III). Seventy compounds showing heme-sparing or inhibitory activity in a Crithidia fasciculata growth system having excess Fe and minimal hemin were prescreened. Of these, 45 were highly trypanocidal for suspensions of bloodstream T. brucei brucei; criteria of activity here were immobilization, lysis, and loss of infectivity. Eighteen of the chelators highly active in the suspension prescreen were tried in T. brucei brucei-infected mice. Thirteen of these chelators were curative in mice with 24-h infections, i.e., they allowed survival >30 days beyond the untreated controls, caffeic acid  [331-39-5], neocuproine  [484-11-7], and 2-pyridinecarboxaldehyde-2-pyridylhydrazone  [2215-33-0] cure 5 out of 5 mice after an i.v. dose of 100 mg/kg. salicylaldehyde thiosemicarbazone  [5351-90-6] Cured 5 of 5 mice at an i.p. dose of 500 mg/kg. Lesser activity was shown by several other chelators.

Journal of Protozoology 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 C13H18BFO2, Product Details of C11H10N4.

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

Garcia Sanchez, F. published the artcileCoupled redox and complex formation processes as a kinetic fluorometric method for the determination of cobalt, Recommanded Product: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, the publication is Fresenius’ Zeitschrift fuer Analytische Chemie (1983), 315(6), 491-5, database is CAplus.

A sensitive and relatively interference-free method for the kinetic determination of Co is described. The method is based on the slow oxidation of 2-pyridinealdehyde 2-pyridylhydrazone (PAPH) by BrO₃^– to a fluorescent product. Complexation of PAPH with Co causes a decrease in the rate of oxidation, which is related to the concentration of Co and also to the stability constant of the complex. The influence of reaction variables and the effect of foreign ions are discussed. Co 20-150 ng mL^-1 can be determined with a relative standard deviation of 4%. The absorption of the 1:2 Co PAPH complex was measured at 440 nm.

Fresenius’ Zeitschrift fuer Analytische Chemie 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, Recommanded Product: 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine.

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

Todeschini, A.R. published the artcile2-Pyridylarylhydrazone derivatives, a new class of platelet aggregation inhibitors, Safety of 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine, the publication is Brazilian Journal of Medical and Biological Research (1996), 29(3), 389-93, database is CAplus and MEDLINE.

A series of 2-pyridylarylhydrazone derivatives was synthesized and compared with a previously reported pyrazole series, i.e., 4-acylpyrazolylarylhydrazone and 5-pyrazolylarylhydrazone, which present antiplatelet aggregation activity. The structures of these pyridylarylhydrazone derivatives were designed on the basis of the known bioisosteric relation of the heteroaromatic ring. The antiplatelet aggregation activity was measured in vitro on citrated platelet-rich rabbit plasma in which aggregation was induced with 5 μM ADP, 5 μg/mL collagen and 200 μM arachidonic acid. Eighteen compounds belonging to the pyridine series were tested at 1 mM concentration and none inhibited ADP-induced rabbit platelet aggregation. 2-(2-Formylfurane)pyridylhydrazone exhibited a highly potent inhibitory activity on arachidonic acid-induced aggregation, with an IC₅₀ of 0.35 μM. These results suggest that the hydrazone unit and the 2-furyl moiety of the arylhydrazone framework are important pharmacophores for antiplatelet activity.

Brazilian Journal of Medical and Biological Research 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 C15H20O6, Safety of 2-((2-(Pyridin-2-yl)hydrazono)methyl)pyridine.

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