September 2022 | Page 26 of 27 | Pyridine-derivatives

Cas: 100-54-9 was involved in experiment | Angewandte Chemie, International Edition 2021

3-Cyanopyridine(cas: 100-54-9) has been shown to have a number of pharmacological effects: it inhibits the production of prostaglandin E2 and nitric oxide in congestive heart failure patients; it prevents the formation of diazonium salt from benzene and nitrogen dioxide; it inhibits the growth of tumor cell lines; and it protects mice from radiation injury by scavenging reactive oxygen species. Quality Control of 3-Cyanopyridine

Quality Control of 3-CyanopyridineIn 2021, Wang, Chang-Sheng;Sun, Qiao;Garcia, Felipe;Wang, Chen;Yoshikai, Naohiko published 《Cobalt-catalyzed intermolecular [2 + 2 + 2] cycloaddition of nitriles and alkynes: facile synthesis of polyarylpyridines and their mechanochemical cyclodehydrogenation to nitrogen-containing polyaromatics》. 《Angewandte Chemie, International Edition》published the findings. The article contains the following contents:

The transition-metal-catalyzed [2+2+2] cycloaddition of nitriles and alkynes is an established synthetic approach to pyridines; however, these cycloadditions often rely on the use of tethered diynes or cyanoalkynes as one of the reactants. Thus, examples of efficient, fully intermol. catalytic [2+2+2] pyridine synthesis, especially those employing unactivated nitriles and internal alkynes leading to pentasubstituted pyridines, remain scarce. Herein, we report on simple and inexpensive catalytic systems based on cobalt(II) iodide, 1,3-bis(diphenylphosphino)propane, and Zn that promote [2+2+2] cycloaddition of various nitriles and diarylacetylenes for the synthesis of a broad range of polyarylated pyridines. DFT studies support a reaction pathway involving oxidative coupling of two alkynes, insertion of the nitrile into a cobaltacyclopentadiene, and C-N reductive elimination. The resulting tetra- and pentaarylpyridines serve as precursors to hitherto unprecedented nitrogen-containing polycyclic aromatic hydrocarbons via mechanochem. assisted multifold reductive cyclodehydrogenation. Transition metal-catalyzed [2 + 2 + 2] cycloaddition of nitriles and alkynes has been extensively developed as a straightforward and atom-economical synthetic approach to pyridines over the last several decades using various transition metal catalysts, both precious and non-precious. Despite this long history, cycloadditions of this type have often relied on the use of tethered diyne or cyanoalkyne as one of the reactants. Thus, examples of efficient, fully intermol. catalytic [2 + 2 + 2] pyridine synthesis, especially those employing unactivated nitriles and internal alkynes leading to pentasubstituted pyridines, remain scarce. Herein, we report on simple and inexpensive catalytic systems based on cobalt(II) iodide, 1,3-bis(diphenylphosphino)propane, and Zn that promote [2 + 2 + 2] cycloaddition of various nitriles and diarylacetylenes without using a large excess of the nitrile. The present systems allow for the synthesis of broad range of polyarylated pyridines, many of which have not been previously accessed by the [2 + 2 + 2] manifold. Computational studies have supported a reaction pathway involving oxidative coupling of two alkynes, insertion of the nitrile into cobaltacyclopentadiene, and C-N reductive elimination, while shedding light on stepwise nature of the oxidative coupling and insertion processes. We also demonstrate that tetra- and pentaarylpyridines can serve as precursors to hitherto unprecedented nitrogen-containing polycyclic aromatic hydrocarbons via mechanochem. assisted multifold reductive cyclodehydrogenation. And 3-Cyanopyridine (cas: 100-54-9) was used in the research process.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Explore more uses of cas: 80-32-0 | BMC Chemistry

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) can be introduced in the drinking water to fabricate aqueous liquid formulations for combating bacterial and protozoal in animals.Formula: C10H9ClN4O2S Besides, sulfachloropyridazine associated to tripelennamine hydrocholoride has been demonstrated to function as an anti-stress agent in poultry after vaccinations.

Hajrulai-Musliu, Zehra;Uzunov, Risto;Jovanov, Stefan;Jankuloski, Dean;Stojkovski, Velimir;Pendovski, Lazo;Sasanya, James Jacob published 《A new LC-MS/MS method for multiple residues/contaminants in bovine meat》 in 2021. The article was appeared in 《BMC Chemistry》. They have made some progress in their research.Formula: C10H9ClN4O2S The article mentions the following:

A multi-class and multi-residue/contaminant method for the determination of veterinary drug and pesticide residues and mycotoxins in bovine meat has been developed and validated. The veterinary drug residues/contaminants included antimicrobials, anabolic hormones, lactones, β-agonists, mycotoxins, and pesticides. Isotopic labeled internal standards were included to compensate residual matrix effects. The calibrators used in the method demonstrated linearity with the R2 > 0.98. The decision limit (CCα) values were in the range from 0.067 to 2103.84μg/kg, while the range for detection capability (CCβ) was from 0.083 to 2482.13μg/kg. The limit of detection (LOD) and limit of quantification (LOQ) were in the range from 0.059 to 291.36μg/kg, and 0.081 to 328.13μg/kg, resp. The recovery of analytes ranged from 61.28% to 116.20%. The intra-day coefficient of variation (CV) was from 0.97 to 25.93% and the inter-day CV was 2.30-34.04%. The method has been used for the determination of 49 residues/contaminants in bovine meat. Application of the method in routine anal. in bovine samples, revealed in limited samples the presences of enrofloxacin, oxytetracycline and sulfadiazine at the concentration of 35.22μg/kg, 27.35μg/kg, and 36.20μg/kg, resp. And 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide (cas: 80-32-0) was used in the research process.

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Liu, Jing et al. published new progress in experiments with the help of cas: 80-32-0

4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide(cas: 80-32-0) is a sulfonamide antibiotic that is usually used as antibacterial anti-inflammatory drug, which has been applied in the treatment of acute urinary tract infections in childhood.Quality Control of 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamideDue to its antibiotic activity, this chemical has been selected as an ingredient to prepare antibacterial composition.

Quality Control of 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamideIn , Liu, Jing;Deng, Wen-Jing;Ying, Guang-Guo;Tsang, Eric P. K.;Hong, Hua-Chang published 《Occurrence and distribution of antibiotics in surface water》. 《Ecotoxicology》published the findings. The article contains the following contents:

The concentrations, distribution, and ecol. risks of 24 typical antibiotics in Hong Kong rivers and seawater were investigated using high-performance liquid chromatog. coupled with electrospray ionization tandem mass spectrometry (UHPLC-EI-MS/MS). The results showed that the select antibiotics were widely distributed in the study area. Among the target antibiotics, the detection rate of tetracyclines (TCs) was 100%, which indicated the widespread use of TCs in Hong Kong. The detection rates of sulfonamides (SAs) (57.1-100%), fluoroquinolones (FQs) (78.6-100%), roxithromycin (RTM) (50%) and novobiocin (NOV) (50%) were all above 50%. Compared with river water (7.9-114.26 ng/L, medium: 27.7 ng/L), concentrations of the most antibiotics in seawater (9.5-32.0 ng/L, medium: 13.3 ng/L) were lower; seawater concentrations were similar to those reported from other coastal cities, such as Guangzhou and Zhuhai in China, which implied that the source of marine antibiotic pollution may be the nearby rivers, and the vastness of the ocean causes environmental dilution of antibiotics. According to the ratio of the measured environmental concentration (MEC) to the predicted no-effect concentration (PNEC), ofloxacin (OFX) (average risk quotient: 1.94E-01) and ciprofloxacin (CFX) (average risk quotient: 3.53E-01) posed medium to high ecol. risk in most places, whereas other antibiotics posed lower risk. In Yuen Long, where there were many livestock farms nearby, the detected concentration of antibiotics was higher, indicating that livestock wastewater may be the major reason for the increase in antibiotic levels in this area. In general, the detected concentration of antibiotics in Hong Kong was lower than that in the United States, Japan, the United Kingdom, and coastal areas of China, but the long-term existence of low concentrations of antibiotics also poses great risks. According to the risk assessment, Hong Kong should pay more attention to the use of FQs (e.g., OFX and CFX) in the future. The experimental procedure involved many compounds, such as 4-Amino-N-(6-chloropyridazin-3-yl)benzenesulfonamide (cas: 80-32-0) .

Reference:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ahemed, Jakeer team published research on Journal of Photochemistry and Photobiology, A: Chemistry in 2021 | 31181-90-5

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%., Reference of 31181-90-5

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. 31181-90-5, formula is C6H4BrNO, Name is 5-Bromopicolinaldehyde. 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. Reference of 31181-90-5.

Ahemed, Jakeer;Pasha, Jakeer;Rao D, Venkateshwar;Kore, Ranjith;Gade, Ramesh;Bhongiri, Yadagiri;Chetti, Prabhakar;Pola, Someshwar research published 《 Synthesis of new Zn (II) complexes for photo decomposition of organic dye pollutants, industrial wastewater and photo-oxidation of methyl arenes under visible-light》, the research content is summarized as follows. Synthesis of new Schiff′s base Zn-complexes for photo-oxidation of Me arenes and xylenes are reported under visible light irradiation conditions. All the synthesized new ligands and Zn-complexes are thoroughly characterized with various spectral analyses and confirmed as 1:1 ratio of Zn and ligand with distorted octahedral structure. The bandgap energies of the ligands are higher than its Zn-complexes. These synthesized new Zn(II) complexes are used for the photo-fragmentation of organic dye pollutants, photodegradation of food industrial wastewater and oxidation of Me arenes which are converted into its resp. aldehydes with moderate yields under visible light irradiation The photooxidation reaction dependency on the intensity of the visible light was also studied. With the increase in the dosage of photocatalyst, the Me groups are oxidized to get aldehydes and mono acid products, which are also identified from LC-MS data. Finally, [Zn(PPMHT)Cl] is with better efficiency than [Zn(PTHMT)Cl] and [Zn(MIMHPT)Cl] for oxidation of Me arenes is reported under visible-light-driven conditions.

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%.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Acharya, Swadhin Swaraj team published research on ACS Omega in 2022 | 1603-41-4

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,, COA of Formula: C6H8N2

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. 1603-41-4, formula is C6H8N2, Name is 2-Amino-5-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. COA of Formula: C6H8N2.

Acharya, Swadhin Swaraj;Bhaumick, Prabhas;Kumar, Rohit;Choudhury, Lokman H. research published 《 Iodine-Catalyzed Multicomponent Synthesis of Highly Fluorescent Pyrimidine-Linked Imidazopyridines》, the research content is summarized as follows. Herein, we report a metal-free one-pot three-component reaction of aryl Me ketones, 2-aminopyridines, and barbituric acids for the synthesis of pyrimidine-linked imidazopyridines using a catalytic amount of mol. iodine in DMSO medium. This process involves a one-pot C-H oxidation, followed by the formation of one C-C and two C-N bonds. A wide variety of aryl Me ketones and 2-aminopyridines were found to be suitable for this methodol. The UV and fluorescence properties of the synthesized products were studied in water and DMSO media. Most of the synthesized products exhibited very good to excellent fluorescence quantum yield. Among all the products, compounds 4p (I) and 4q (II) showed the maximum fluorescence quantum yield (0.36) in water medium under basic conditions and compound 4c (III) showed the maximum fluorescence quantum yield (0.75) in DMSO medium.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Abel, A. S. team published research on Russian Chemical Bulletin in 2015 | 766-11-0

COA of Formula: C5H3BrFN, 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.

Pyridine is colorless, but older or impure samples can appear yellow. 766-11-0, formula is C5H3BrFN, Name is 5-Bromo-2-fluoropyridine. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Historically, pyridine was produced from coal tar. COA of Formula: C5H3BrFN.

Abel, A. S.;Grigorova, O. K.;Averin, A. D.;Maloshitskaya, O. A.;Popov, O. A.;Butov, G. M.;Savelyev, E. N.;Orlinson, B. S.;Novakov, I. A.;Beletskaya, I. P. research published 《 Catalyst-free amination of 2-fluoropyridine and 2-fluoro-5-halopyridines with adamantane amines》, the research content is summarized as follows. Catalyst-free reactions of 2-fluoropyridine with amines and diamines bearing the adamantyl moiety at either the N atom or in the side chain were studied. Amines, which do not contain secondary alkyl substituents at the amino group, react with an excess of 2-fluoropyridine to give N-(pyridin-2-yl) derivatives in the yields from moderate to good. 2-Fluoro-5-halopyridines were found to be more reactive than 2-fluoropyridine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Abdelsamie, Ahmed S. team published research on Journal of Medicinal Chemistry in 2019 | 16133-25-8

16133-25-8, Pyridine-3-sulfonyl chloride is a useful research compound. Its molecular formula is C5H4ClNO2S and its molecular weight is 177.61 g/mol. The purity is usually 95%.
Pyridine-3-sulfonyl chloride is a reagent used in the synthesis of pyrimidine derivatives with anti-proliferative activity against negative breast cancer cells.
Pyridine-3-sulfonyl chloride is a chemical compound that binds to the active site of cytochrome P450 enzymes. It can be used to study the effects of matrix effect on reaction solution. Pyridine-3-sulfonyl chloride has been shown to have an UV absorption spectrum with a maximum at 280 nm and a p450 activity that is proportional to the concentration of human serum. This compound has been shown to inhibit kinase domain in vitro assays, which may have clinical relevance in the treatment of obesity., Category: pyridine-derivatives

At 25 °C pyridine has a viscosity of 0.88 mPa/s and thermal conductivity of 0.166 W·m−1·K−1. 16133-25-8, formula is C5H4ClNO2S, Name is Pyridine-3-sulfonyl chloride. 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. Category: pyridine-derivatives.

Abdelsamie, Ahmed S.;Salah, Mohamed;Siebenbuerger, Lorenz;Merabet, Ahmed;Scheuer, Claudia;Frotscher, Martin;Mueller, Sebastian T.;Zierau, Oliver;Vollmer, Guenter;Menger, Michael D.;Laschke, Matthias W.;van Koppen, Chris J.;Marchais-Oberwinkler, Sandrine;Hartmann, Rolf W. research published 《 Design, Synthesis, and Biological Characterization of Orally Active 17β-Hydroxysteroid Dehydrogenase Type 2 Inhibitors Targeting the Prevention of Osteoporosis》, the research content is summarized as follows. Osteoporosis is predominantly treated with drugs that inhibit further bone resorption due to estrogen deficiency. Yet, osteoporosis drugs that not only inhibit bone resorption but also stimulate bone formation, such as potentially inhibitors of 17β-hydroxysteroid dehydrogenase type 2 (17β-HSD2), may be more efficacious in the treatment of osteoporosis. Blockade of 17β-HSD2 is thought to increase intracellular estradiol and testosterone in bone, thereby inhibiting bone resorption by osteoclasts and stimulating bone formation by osteoblasts, resp. We here describe the design, synthesis, and biol. characterization of a novel bicyclic-substituted hydroxyphenylmethanone 17β-HSD2 inhibitor (I). Compound I is a nanomolar potent inhibitor of human 17β-HSD2 (IC₅₀ of 6.1 nM) and rodent 17β-HSD2 with low in vitro cellular toxicity, devoid of detectable estrogen receptor α affinity, displays high aqueous solubility and in vitro metabolic stability, and has an excellent oral pharmacokinetic profile for testing in a rat osteoporosis model. Administration of I in a rat osteoporosis model demonstrates its bone-sparing efficacy.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Wan, Lin-Xi team published research on ACS Omega in 2021 | 5315-25-3

Application 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.

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 of C6H6BrN.

Wan, Lin-Xi;Miao, Shi-Xing;He, Zhen-Xiang;Li, Xiaohuan;Zhou, Xian-Li;Gao, Feng research published 《 Pd-Catalyzed Direct Modification of an Anti-Alzheimer’s Disease Drug: Synthesis and Biological Evaluation of α-Aryl Donepezil Analogues》, the research content is summarized as follows. Palladium/BuAd₂P catalyzed efficiently the direct α-arylation of ketone in the anti-Alzheimer’s disease drug donepezil I (Ar = H), leading to 15 aryldonepezil analogs I (Ar = 3-methylpyridin-2-yl (II), 4-chlorophenyl, naphth-1-yl, etc.) exhibiting high selective inhibition of acetylcholinesterase (AChE). The cell-based assays revealed that the 3-methylpridinyl analog (II) shows significantly lower toxicity compared to donepezil and remarkable neuroprotective activity against H₂O₂-induced damage in SH-SY5Y cells. Docking results of compound II also interpreted the possible mechanism of the selective inhibition between AChE and butyrylcholinesterase.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Lv, Jie team published research on Journal of Molecular Structure in 2022 | 31181-90-5

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%.

The critical parameters of pyridine are pressure 6.70 MPa, temperature 620 K and volume 229 cm3·mol−1. 31181-90-5, formula is C6H4BrNO, Name is 5-Bromopicolinaldehyde. In the temperature range 340–426 °C its vapor pressure p can be described with the Antoine equation.. Related Products of 31181-90-5.

Lv, Jie;Lu, Yinfu;Wang, Jinglan;Zhao, Feng;Wang, Yibo;He, Haifeng;Wu, Yaqian research published 《 Schiff base-type copper(I) complexes exhibiting high molar extinction coefficients: Synthesis, characterization and DFT studies》, the research content is summarized as follows. The three Schiff base-type Cu(I) complexes [Cu(POP)(NN̂)]PF₆, NN̂ = N,N-diphenyl-4-(6-((phenylimino)methyl)pyridin-3-yl)aniline (P1), N-((5-(4-(diphenylamino)phenyl)pyridin-2-yl)methylene)naphthalen-2-amine(P2), N-((5-(4-(diphenylamino)phenyl)pyridin-2-yl)methylene)adamantan-1-amine (P3), were prepared and characterized. The photophys. properties of these Cu(I) complexes is tuned by the addition of different substituents such as Ph, naphthyl and adamantanyl groups into the backbone of Schiff base ligand. The resulting complexes exhibit high absorption ability in the visible region with molar absorptivities of up to 3 7400 M^-1 cm^-1. The emissions in CH₂Cl₂ solution are at 551-552 nm with lower quantum yields of 1.1-2.0% and short-lived excited lifetimes of 2.78-3.09 ns for all the complexes at room temperature The photophys. properties were further explained by DFT and TDDFT methods.

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%.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kan, Chun team published research on Journal of Photochemistry and Photobiology, A: Chemistry in 2020 | 16133-25-8

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. 16133-25-8, formula is C5H4ClNO2S, Name is Pyridine-3-sulfonyl chloride. 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. Electric Literature of 16133-25-8.

Kan, Chun;Shao, Xiaotao;Wu, Linyun;Zhang, Yao;Bao, Xiaofeng;Zhu, Jing research published 《 A novel “OFF-ON-OFF” fluorescence chemosensor for hypersensitive detection and bioimaging of Al(III) in living organisms and natural water environment》, the research content is summarized as follows. High-selectivity detection of trace Al³⁺ ions in water and biol. systems by a fluorescence imaging method is not yet mature. Herein, we synthesized a novel reversible Al³⁺-specific fluorescent probe named RBLF by linking Rhodamine B and pyridine-3-sulfonyl chloride through o-phenylenediamine in several reactions. RBLF exhibited an ultra-high sensitive and excellent selective response towards Al³⁺ by fluorescence and UV-vis spectra in aqueous solutions What is more worth mentioning is that its response is fast, dual changes in color and fluorescence of the probe solution that can occur instantaneously after adding with Al³⁺. Its detection limit for Al³⁺ ions in aqueous system solutions is 14.23 nM, which is far below the maximum allowable amount of Al³⁺ in drinking water. Moreover, the probe provided an effective method for detecting low concentrations of Al³⁺ in natural water, living cells, zebrafish and plant tissues.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem