Day: September 20, 2022

At 25 °C pyridine has a viscosity of 0.88 mPa/s and thermal conductivity of 0.166 W·m−1·K−1. 31181-90-5, formula is C6H4BrNO, Name is 5-Bromopicolinaldehyde. The enthalpy of vaporization is 35.09 kJ·mol−1 at the boiling point and normal pressure.The enthalpy of fusion is 8.28 kJ·mol−1 at the melting point. Quality Control of 31181-90-5.

Cui, Shiqiang;Qiu, Shouyu;Lu, Ruimin;Pu, Shouzhi research published 《 A multi-functional fluorescent sensor for Zn²⁺ and HSO^–₄ based on a new diarylethene derivative》, the research content is summarized as follows. A new photochromic diarylethene derivative with a hydralazine unit was designed and synthesized. It was not only acted as a Zn²⁺ sensor with the fluorescent color change from dark blue to bright orange, but also acted as a fluorescent sensor for HSO^–₄ with the fluorescent color change from dark blue to bright blue. Also, the derivative also exhibits multi-addressable switching properties by the stimulations of lights and chem. reagents. Based on these characteristics, two combinational logic circuits were constructed with the emission intensity as the output signals, and the UV/visible lights, chem. species as the input signals.

Quality Control of 31181-90-5, 5-Bromopyridine-2-carbaldehyde is a useful research compound. Its molecular formula is C6H4BrNO and its molecular weight is 186.01 g/mol. The purity is usually 95%.

5-Bromopyridine-2-carbaldehyde is a water soluble organic molecule that has been shown to inhibit the mitochondrial respiratory chain. It is a structural analog of the natural substrate for mitochondrial cytochrome c oxidase, 5-aminolevulinic acid. This compound has been shown to be selective against cancer cells and has anti-viral properties. The photophysical properties of 5-bromopyridine-2-carbaldehyde have been studied extensively. The fluorescence quantum yield of this molecule in aqueous solution is 0.06%., 31181-90-5.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridine is diamagnetic and has a diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1.The molecular electric dipole moment is 2.2 debyes. 5315-25-3, formula is C6H6BrN, Name is 2-Bromo-6-methylpyridine. TThe standard enthalpy of formation is 100.2 kJ·mol−1 in the liquid phase and 140.4 kJ·mol−1 in the gas phase. Product Details of C6H6BrN.

Cook, Xinlan A. F.;Pantaine, Loic R. E.;Blakemore, David C.;Moses, Ian B.;Sach, Neal W.;Shavnya, Andre;Willis, Michael C. research published 《 Base-Activated Latent Heteroaromatic Sulfinates as Nucleophilic Coupling Partners in Palladium-Catalyzed Cross-Coupling Reactions》, the research content is summarized as follows. Heteroaromatic sulfinates, e.g., I, are effective nucleophilic reagents in Pd(0)-catalyzed cross-coupling reactions with aryl halides e.g., 4-methoxy-bromobenzene. However, metal sulfinate salts can be challenging to purify and solubilize in reaction media, and are not tolerant to multi-step transformations. Here base-activated, latent sulfinate reagents: β-nitrile and β-ester sulfones were introduced. It was shown that, under the cross-coupling conditions, these species generate the sulfinate salt in situ, which then undergo efficient palladium-catalyzed desulfinative cross-coupling with (hetero)aryl bromides to deliver a broad range of biaryls, e.g., II. These latent sulfinate reagents have proven to be stable through multi-step substrate elaboration, and amenable to scale-up.

Product Details of C6H6BrN, 2-Bromo-6-methylpyridine (2BMPy) is a bromopyridine derivative. It is formed when 2-chloro-6-methylpyridine is heated with bromotrimethylsilane. Its synthesis from various methods have been reported.
2-Bromo-6-methylpyridine is a building block in the preparation of nitrogen containing heterocyclic compounds.
2-Bromo-6-methylpyridine is an organic compound that belongs to the group of pyridinium halides. It is soluble in common solvents such as water, ethanol, and acetone. 2BMPy has been shown to act as a glutamate receptor antagonist and has been used in the study of glutamate receptors, including their subtypes. This chemical has also been shown to have antioxidant properties and can be used in the prevention of atherosclerosis., 5315-25-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridine is colorless, but older or impure samples can appear yellow. 5315-25-3, formula is C6H6BrN, Name is 2-Bromo-6-methylpyridine. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Historically, pyridine was produced from coal tar. Formula: C6H6BrN.

Conn, Edward L.;Perry, Matthew A.;Shi, Kecheng;Wang, Guotao;Hoy, Susan;Sach, Neal W.;Qi, Wenying;Qu, Liqiang;Gao, Yu;Xu, Yan;Schmitt, Daniel C. research published 《 Identification of parallel medicinal chemistry protocols to expand branched amine design space》, the research content is summarized as follows. Methods for the synthesis of α-branched heteroaryl amines RCH(R¹)NH(R²) (R = tert-Bu, Ph, 1-methyl-1H-imidazol-4-yl, pyridin-2-yl, etc. R¹ = 1-methyl-1H-pyrazol-5-yl, pyridin-3-yl, 1-propyl-1H-pyrazol-4-yl, 4-bromo-2-hydroxyphenyl, etc.; R² = pyridin-2-yl, Ph, 4-phenylpyridin-2-yl, pyrazin-2-yl, etc.) via aldimine addition have been evaluated for compatibility with parallel synthesis. In situ activation of aliphatic carboxylic acids RC(O)OH as redox-active esters enables Zn-mediated decarboxylative radical imine R¹CH=NR² addition to access aliphatic-branched heterobenzylic amines. In situ activation of (hetero)aryl bromides RBr via Li-halogen exchange enables heteroaryl-lithium addition to imines to access (hetero)benzhydryl amines. Condensation of heteroaryl amines RNH₂ with heteroaryl aldehydes R¹CHO provides aldimines which may be intercepted with aryl Grignard reagents to provide modular access to (hetero)benzhydryl amines. These protocols minimize synthetic step count and maximize accessible design space, enhancing access to α-branched heteroaryl amines for medicinal chem.

Formula: C6H6BrN, 2-Bromo-6-methylpyridine (2BMPy) is a bromopyridine derivative. It is formed when 2-chloro-6-methylpyridine is heated with bromotrimethylsilane. Its synthesis from various methods have been reported.
2-Bromo-6-methylpyridine is a building block in the preparation of nitrogen containing heterocyclic compounds.
2-Bromo-6-methylpyridine is an organic compound that belongs to the group of pyridinium halides. It is soluble in common solvents such as water, ethanol, and acetone. 2BMPy has been shown to act as a glutamate receptor antagonist and has been used in the study of glutamate receptors, including their subtypes. This chemical has also been shown to have antioxidant properties and can be used in the prevention of atherosclerosis., 5315-25-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridine has a conjugated system of six π electrons that are delocalized over the ring. 766-11-0, formula is C5H3BrFN, Name is 5-Bromo-2-fluoropyridine. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. Application In Synthesis of 766-11-0.

Collibee, Scott E.;Bergnes, Gustave;Chuang, Chihyuan;Ashcraft, Luke;Gardina, Jeffrey;Garard, Marc;Jamison, Chris R.;Lu, Kevin;Lu, Pu-Ping;Muci, Alexander;Romero, Antonio;Valkevich, Ellen;Wang, Wenyue;Warrington, Jeffrey;Yao, Bing;Durham, Nickie;Hartman, James;Marquez, Anna;Hinken, Aaron;Schaletzky, Julia;Xu, Donghong;Hwee, Darren T.;Morgans, David;Malik, Fady I.;Morgan, Bradley P. research published 《 Discovery of Reldesemtiv, a Fast Skeletal Muscle Troponin Activator for the Treatment of Impaired Muscle Function》, the research content is summarized as follows. Herein, the discovery of reldesemtiv I, a second-generation fast skeletal muscle troponin activator (FSTA) that increases force production at submaximal stimulation frequencies, is reported. Property-based optimization of high throughput screening hit, 4-(4-fluorobenzyl)-5-(phenethylamino)-1,2,4-thiadiazole, led to compounds with improved free exposure and in vivo muscle activation potency compared to the first-generation FSTA, tirasemtiv. The compound I demonstrated increased muscle force generation in a phase 1 clin. trial and is currently being evaluated in clin. trials for the treatment of amyotrophic lateral sclerosis.

766-11-0, 5-Bromo-2-fluoropyridine is a useful research compound. Its molecular formula is C5H3BrFN and its molecular weight is 175.99 g/mol. The purity is usually 95%.
5-Bromo-2-fluoropyridine is a boronic acid that has been shown to react with iodides and form 5-bromo-2-fluoroiodobenzene. The reaction of 5-bromo-2-fluoropyridine with benzene gives the same product as the reaction with 1,3,5-trioxane. The UV absorption of 5-bromo-2-fluoropyridine is found at 230 nm and 260 nm. It also has an absorption band in the infrared region at 1625 cm−1. Vibrational progressions have been observed for this molecule, which are due to dipole moments and electron density distributions in the molecule.
5-bromo-2-fluoropyridine is used in the synthesis of heteroaromatic and aniline derivatives of piperidines as potent ligands used for vesicular acetylcholine transport. , Application In Synthesis of 766-11-0

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one methine group (=CH−) replaced by a nitrogen atom. 5315-25-3, formula is C6H6BrN, Name is 2-Bromo-6-methylpyridine. It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish-like smell. Name: 2-Bromo-6-methylpyridine.

Clarke, Joshua J.;Maekawa, Yuuki;Nambo, Masakazu;Crudden, Cathleen M. research published 《 Borenium-Catalyzed Reduction of Pyridines Through the Combined Action of Hydrogen and Hydrosilane》, the research content is summarized as follows. Mesoionic carbene-stabilized borenium ions efficiently reduce substituted pyridines to piperidines in the presence of hydrosilane and hydrogen atm. Control experiments and deuterium labeling studies demonstrated a reversible hydrosilylation of the pyridine, enabling the full reduction of the N-heterocycle under milder conditions. Silane was a critical reaction component to prevent adduct formation between the piperidine product and the borenium catalyst.

Name: 2-Bromo-6-methylpyridine, 2-Bromo-6-methylpyridine (2BMPy) is a bromopyridine derivative. It is formed when 2-chloro-6-methylpyridine is heated with bromotrimethylsilane. Its synthesis from various methods have been reported.
2-Bromo-6-methylpyridine is a building block in the preparation of nitrogen containing heterocyclic compounds.
2-Bromo-6-methylpyridine is an organic compound that belongs to the group of pyridinium halides. It is soluble in common solvents such as water, ethanol, and acetone. 2BMPy has been shown to act as a glutamate receptor antagonist and has been used in the study of glutamate receptors, including their subtypes. This chemical has also been shown to have antioxidant properties and can be used in the prevention of atherosclerosis., 5315-25-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one methine group (=CH−) replaced by a nitrogen atom. 5315-25-3, formula is C6H6BrN, Name is 2-Bromo-6-methylpyridine. It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish-like smell. COA of Formula: C6H6BrN.

Cho, Yae In;Durgaprasad, Gummadi;Rose, Michael J. research published 《 CNS and CNP Iron(II) Mono-Iron Hydrogenase (Hmd) Mimics: Role of Deprotonated Methylene(acyl) and the trans-Acyl Site in H₂ Heterolysis》, the research content is summarized as follows. The authors report synthesis and H₂ activation involving model complexes of monoiron hydrogenase (Hmd) derived from acyl-containing pincer ligand precursors bearing thioether (CNS^Pre) or phosphine (CNP^Pre) donor sets. Both complexes feature pseudo-octahedral iron(II) dicarbonyl units. While the CNS pincer adopts the expected mer-CNS (pincer) geometry, the CNP ligand unexpectedly adopts the fac-CNP coordination geometry. Both complexes exhibit an acidic methylene C-H bond (reversibly de/protonated by a bulky phenolate), which affords a dearomatized pyridinate-bound intermediate. Notably, dearomatization of Fe-CNS also results in deligation of the thioether sulfur donor, generating an open coordination site trans from the acyl unit. In contrast, Fe-CNP maintains a CO ligand trans from the acyl site both in the parent and dearomatized complexes (-PPh₂ donor is cis to acyl). The dearomatized mer-Fe-CNS was competent for H₂ activation (5 atm D_2(g) plus phenolate as base), which is attributed to both the basic site on the ligand framework and the open coordination site trans to the acyl donor. In contrast, the dearomatized fac-Fe-CNP was not competent for H₂ activation, which is ascribed to the blocked coordination site trans from acyl (occupied by CO ligand). These results highlight the importance of both (i) the open coordination site trans to the organometallic acyl donor, and (ii) a pendant base in the enzyme active site.

5315-25-3, 2-Bromo-6-methylpyridine (2BMPy) is a bromopyridine derivative. It is formed when 2-chloro-6-methylpyridine is heated with bromotrimethylsilane. Its synthesis from various methods have been reported.
2-Bromo-6-methylpyridine is a building block in the preparation of nitrogen containing heterocyclic compounds.
2-Bromo-6-methylpyridine is an organic compound that belongs to the group of pyridinium halides. It is soluble in common solvents such as water, ethanol, and acetone. 2BMPy has been shown to act as a glutamate receptor antagonist and has been used in the study of glutamate receptors, including their subtypes. This chemical has also been shown to have antioxidant properties and can be used in the prevention of atherosclerosis., COA of Formula: C6H6BrN

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

At 25 °C pyridine has a viscosity of 0.88 mPa/s and thermal conductivity of 0.166 W·m−1·K−1. 1603-41-4, formula is C6H8N2, Name is 2-Amino-5-methylpyridine. The enthalpy of vaporization is 35.09 kJ·mol−1 at the boiling point and normal pressure.The enthalpy of fusion is 8.28 kJ·mol−1 at the melting point. Recommanded Product: 2-Amino-5-methylpyridine.

Chitrakar, Ravi;Rawat, Deepa;Sistla, Ramakrishna;Vadithe, Lakshma Nayak;Subbarayappa, Adimurthy research published 《 Design, synthesis and anticancer activity of sulfenylated imidazo-fused heterocycles》, the research content is summarized as follows. The design, synthesis and study of anticancer properties of sulfenylated 2-phenylimidazo[1,2-a]pyridines I [R = H, Me, Cl, Ph; Ar = (E)-styryl, 4-methylsulfanylphenyl, 1-naphthyl, etc.; Ar¹ = Ph, 4-ClPh, 1-naphthyl] and their analogs were prepared A set of twenty sulfenylated imidazo[1, 2-a]pyridine derivatives I were synthesized. Whereby elusive amendmented to the imidazo[1,2-a]pyridine motif confer dramatic changes in functional affinity of a novel action to modulate anticancer activity in seven different human cancer cell lines i.e.: MDA MB 231 (breast), HepG2 (liver), Hela (cervical), A549 (lung), U87MG (glioblastoma), SKMEL-28 (skin melanoma) and DU-145 (prostate) by employing MTT assay. Among the series, compounds I [R = H, Ar = 1-naphthyl, Ar¹ = Ph; R = H, Ar = (E)-styryl, Ar¹ = Ph; R = H, Ar = 4-methylsulfanylphenyl, Ar¹ = Ph] showed potent activity towards human liver cancer cells HepG2. Cell cycle anal. results revealed that these compounds I [R = H, Ar = 1-naphthyl, Ar¹ = Ph; R = H, Ar = (E)-styryl, Ar¹ = Ph; R = H, Ar = 4-methylsulfanylphenyl, Ar¹ = Ph] arrested the cell cycle at G2/M phase and induced apoptosis in human liver cancer cells HepG2. It was further confirmed by Hoechst staining, Measurement of mitochondrial membrane potential (ΔΨm) and Annexin V-FITC assay.

1603-41-4, 2-Amino-5-methylpyridine, also known as 2-Amino-5-methylpyridine, is a useful research compound. Its molecular formula is C6H8N2 and its molecular weight is 108.14 g/mol. The purity is usually 95%.
2-Amino-5-methylpyridine is a chemical compound that belongs to the group of methyl ketones. It has a nitrogen atom and an oxygen atom in its structure, which allows it to form hydrogen bonds with other molecules. 2-Amino-5-methylpyridine can be obtained by reacting hydrochloric acid and xanthone in the presence of a base. The compound is highly reactive and has been shown to have antiinflammatory properties. This can be attributed to its ability to inhibit prostaglandin synthesis. 2-Amino-5-methylpyridine also has fluorescence properties that are sensitive to pH changes and can be used as a probe for metal ions. 2-Amino-5-methylpyridine is an organic compound that contains a methyl group, two nitrogen atoms, and one oxygen atom in its chemical structure. This molecule can form hydrogen bonds with other molecules due to its nitrogen atoms and oxygen atom,, Recommanded Product: 2-Amino-5-methylpyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one methine group (=CH−) replaced by a nitrogen atom. 766-11-0, formula is C5H3BrFN, Name is 5-Bromo-2-fluoropyridine. It is a highly flammable, weakly alkaline, water-miscible liquid with a distinctive, unpleasant fish-like smell. Safety of 5-Bromo-2-fluoropyridine.

Chiotellis, Aristeidis;Ahmed, Hazem;Betzel, Thomas;Tanriver, Matthias;White, Christopher J.;Song, Haewon;Da Ros, Sara;Schibli, Roger;Bode, Jeffrey W.;Ametamey, Simon M. research published 《 Chemoselective ¹⁸F-incorporation into pyridyl acyltrifluoroborates for rapid radiolabelling of peptides and proteins at room temperature》, the research content is summarized as follows. A new prosthetic group is reported for ¹⁸F-labeling of peptides and proteins based on the chemoselective ligation of potassium acyltrifluoroborates (KATs) and hydroxylamines without any detectable ¹⁸F/¹⁹F isotope exchange at the acyltrifluoroborate moiety. The new building block is appended via a common amide bond at room temperature with no need for protecting groups which enables an effective orthogonal ¹⁸F-radiolabelling.

766-11-0, 5-Bromo-2-fluoropyridine is a useful research compound. Its molecular formula is C5H3BrFN and its molecular weight is 175.99 g/mol. The purity is usually 95%.
5-Bromo-2-fluoropyridine is a boronic acid that has been shown to react with iodides and form 5-bromo-2-fluoroiodobenzene. The reaction of 5-bromo-2-fluoropyridine with benzene gives the same product as the reaction with 1,3,5-trioxane. The UV absorption of 5-bromo-2-fluoropyridine is found at 230 nm and 260 nm. It also has an absorption band in the infrared region at 1625 cm−1. Vibrational progressions have been observed for this molecule, which are due to dipole moments and electron density distributions in the molecule.
5-bromo-2-fluoropyridine is used in the synthesis of heteroaromatic and aniline derivatives of piperidines as potent ligands used for vesicular acetylcholine transport. , Safety of 5-Bromo-2-fluoropyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. 766-11-0, formula is C5H3BrFN, Name is 5-Bromo-2-fluoropyridine. For this reason, pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ·mol−1 in pyridine vs. 150 kJ·mol−1 in benzene). Recommanded Product: 5-Bromo-2-fluoropyridine.

Cheung, Chi Wai;Hu, Xile research published 《 Stereoselective Synthesis of Trisubstituted Alkenes through Sequential Iron-Catalyzed Reductive anti-Carbozincation of Terminal Alkynes and Base-Metal-Catalyzed Negishi Cross-Coupling》, the research content is summarized as follows. The stereoselective synthesis of trisubstituted alkenes is challenging. Here, it is shown that an iron-catalyzed anti-selective carbozincation of terminal alkynes can be combined with a base-metal-catalyzed cross-coupling to prepare trisubstituted alkenes in a one-pot reaction and with high regio- and stereocontrol. Cu-, Ni-, and Co-based catalytic systems are developed for the coupling of sp-, sp²-, and sp³-hybridized carbon electrophiles, resp. The method encompasses a large substrate scope, as various alkynyl, aryl, alkenyl, acyl, and alkyl halides are suitable coupling partners. Compared with conventional carbometalation reactions of alkynes, the current method avoids pre-made organometallic reagents and has a distinct stereoselectivity.

Recommanded Product: 5-Bromo-2-fluoropyridine, 5-Bromo-2-fluoropyridine is a useful research compound. Its molecular formula is C5H3BrFN and its molecular weight is 175.99 g/mol. The purity is usually 95%.
5-Bromo-2-fluoropyridine is a boronic acid that has been shown to react with iodides and form 5-bromo-2-fluoroiodobenzene. The reaction of 5-bromo-2-fluoropyridine with benzene gives the same product as the reaction with 1,3,5-trioxane. The UV absorption of 5-bromo-2-fluoropyridine is found at 230 nm and 260 nm. It also has an absorption band in the infrared region at 1625 cm−1. Vibrational progressions have been observed for this molecule, which are due to dipole moments and electron density distributions in the molecule.
5-bromo-2-fluoropyridine is used in the synthesis of heteroaromatic and aniline derivatives of piperidines as potent ligands used for vesicular acetylcholine transport. , 766-11-0.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Pyridine is diamagnetic and has a diamagnetic susceptibility of −48.7 × 10−6 cm3·mol−1.The molecular electric dipole moment is 2.2 debyes. 5315-25-3, formula is C6H6BrN, Name is 2-Bromo-6-methylpyridine. TThe standard enthalpy of formation is 100.2 kJ·mol−1 in the liquid phase and 140.4 kJ·mol−1 in the gas phase. Application In Synthesis of 5315-25-3.

Cheruku, Srinivas;Sajith, Ayyiliath M.;Narayana, Yatheesh;Shetty, Poornima;Nagarakere, Sandhya C.;Sagar, Kunigal S.;Manikyanally, Kumara N.;Rangappa, Kanchugarkoppal Subbegowda;Mantelingu, Kempegowda research published 《 Co₂(CO)₈ as a Solid CO (g) Source for the Amino Carbonylation of (Hetero)aryl Halides with Highly Deactivated (Hetero)arylamines》, the research content is summarized as follows. Carbonylation of (hetero)aryl halides with highly deactivated 2-aminopyridines using Pd-Co(CO)₄ bimetallic catalysis was accomplished. The use of Co₂(CO)₈ as a solid CO(g) source enhanced reaction rates observed when compared to CO(g) and excellent yields highlight the versatility of the developed protocol. A wide range of electronically and sterically demanding heterocyclic amines and (hetero)aryl halides employed and resulted in excellent yields of amino carbonylated products. The developed methodol. was further extended to synthesize Trypanosome brucie and luciferase inhibitors.

Application In Synthesis of 5315-25-3, 2-Bromo-6-methylpyridine (2BMPy) is a bromopyridine derivative. It is formed when 2-chloro-6-methylpyridine is heated with bromotrimethylsilane. Its synthesis from various methods have been reported.
2-Bromo-6-methylpyridine is a building block in the preparation of nitrogen containing heterocyclic compounds.
2-Bromo-6-methylpyridine is an organic compound that belongs to the group of pyridinium halides. It is soluble in common solvents such as water, ethanol, and acetone. 2BMPy has been shown to act as a glutamate receptor antagonist and has been used in the study of glutamate receptors, including their subtypes. This chemical has also been shown to have antioxidant properties and can be used in the prevention of atherosclerosis., 5315-25-3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem