Pyridine-derivatives

Xiao, Yue; Li, Yang; Zhang, Bohan; Li, Hui; Cheng, Zehong; Shi, Jianqiao; Xiong, Jing; Bai, Yugang; Zhang, Ke published the artcile< Functionalizable, Side Chain-Immolative Poly(benzyl ether)s>, Related Products of 2127-03-9, the main research area is selfimmolative polybenzylether.

Herein, we report a poly(benzyl ether)-based self-immolative polymer (SIP) with pendant pyridine disulfide groups. Cleavage of the side-chain disulfides leads to the formation of phenolates, which initiate depolymerization from the side chain. Due to the higher d. of the disulfide groups compared to that of the chain-end-capping group, which normally is responsible for initiating depolymerization of SIPs, the side chain-immolative polymer (ScIP) can be readily degraded in the solid state where the mobility of polymer chains is substantially limited. The ScIP was also further modified through the thiol-disulfide exchange reaction to prepare ScIP-g-poly(ethylene glycol) graft polymers and organogels, which were also able to undergo complete reductive self-immolative degradation

ACS Macro Letters published new progress about Depolymerization. 2127-03-9 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2S2, Related Products of 2127-03-9.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Lu, Hongyan; Zhao, Qinfu; Wang, Xiudan; Mao, Yuling; Chen, Caishun; Gao, Yikun; Sun, Changshan; Wang, Siling published the artcile< Multi-stimuli responsive mesoporous silica-coated carbon nanoparticles for chemo-photothermal therapy of tumor>, Name: 1,2-Di(pyridin-2-yl)disulfane, the main research area is mesoporous silica carbon nanoparticle delivery chemophotothermal therapy cancer; Carbon dots; Chemo-photothermal synergistic therapy; Controlled release; Mesoporous silica-coated mesoporous carbon; Stimuli-response.

In this work, a traceable dual-porous mesoporous silica-coated mesoporous carbon nanocomposite with high drug loading capacity and high photothermal conversion efficiency (30.5%) was successfully prepared Based on the nanocomposite, a pH/redox/near IR multi-stimuli responsive drug delivery system was constructed to realize the accurate drug delivery, drug controlled release and chemo-photothermal synergistic antitumor therapy. MCN@Si was used as a vehicle to load doxorubicin with a high drug loading efficacy of 48.2% and a NIR absorbance agent for photothermal therapy and NIR thermal imaging. Carbon dots with proper size were covalently attached to the surface of MCN@Si via disulfide bonds to block the mesopores, preventing DOX premature release from DOX/MCN@Si-CDs. DOX was rapidly released at the condition of low pH and high GSH concentration due to the breakage of disulfide bonds and protonation of DOX. Moreover, the local hyperthermia generated by MCN@Si-CDs under NIR irradiation could not only directly kill cells, but also accelerate DOX release and enhance cells sensitivity and permeability. Two-dimensional cells and three-dimensional tumor spheroids assays illustrated that DOX/MCN@Si-CDs + NIR group exhibited thermochemotherapy synergistic treatment effect and combination index was 0.378. All the results demonstrated that DOX/MCN@Si-CDs is a traceable multi-stimuli responsive nanodelivery system and can achieve efficient chemo-photothermal synergistic antitumor therapy.

Colloids and Surfaces, B: Biointerfaces published new progress about Antitumor agents. 2127-03-9 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2S2, Name: 1,2-Di(pyridin-2-yl)disulfane.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

den Hertog, H. J.; Schogt, J. C. M.; de Bruyn, J.; de Klerk, A. published the artcile< Derivatives of pyridine and quinoline. LXXXIII. Chloropyridines>, Recommanded Product: 2,3,4,6-Tetrachloropyridine, the main research area is .

2,4,5-Trichloropyridine has been synthesized, 6 other chloropyridines reëxamd., and the m. ps. and b. ps. of 19 chloropyridines determined Nicotinic acid (5 g.) divided in 2 tubes was shaken 4 h. at 250-70° with 42 g. PCl5 and 20 g. POCl3; steam distillation gave an oil and a precipitate which was refluxed 1 h. with 20 mL. 80% H2SO4, diluted with H2O, made basic, and steam-distilled; various fractions m. above 65° [cf. Seyfferth, J. prakt. Chem. 34, 241(1886)], and from the last fraction 2,3,5,6-tetrachloropyridine, m. 90-0.5°, was isolated. 3-Bromo-2,4-dihydroxypyridine (I) (5 g.) and 25 mL. 48% HBr heated 3 h. at 200° in 2 sealed tubes gave, after adding H2O and allowing to stand, 0.5 g. I and from the mother liquor 3.1 g. 5-bromo-2,4-dihydroxypyridine, m. 226.5-7.5°; 1 g. heated 2 h. at 200° with 10 mL. 38% HCl gave 3-chloro-2,4-dihydroxypyridine, decompose about 310°. Et 2,4-dihydroxy-5-pyridinecarboxylate (II) (3 g.) heated 2.5 h. at 115-20° with 18 g. POCl3 gave on steam distillation 90% of the 2,4-di-Cl compound (III), m. 31.5-2°. Saponification with an equivalent amount of dilute NaOH for 0.5 h. gave 80% 2,4-dichloro-5-pyridinecarboxylic acid “”hydrate”” (IV), m. 198° after liquefying at 155° and resolidifying, which could not be dehydrated by recrystallization from EtOH, C6H6, or ligroin, or by sublimation. IV (10 g.) and 10-15 g. POCl3 warmed to 100°, treated gradually with 30 g. PCl5, heated at 140° 0.5 h., evaporated under a vacuum, and the residue dissolved in C6H6 and saturated with NH3 gave 85% 2,4-dichloro-5-pyridinecarboxylic acid, m. 152-3° (from H2O). III (1.7 g.) in 2-3 mL. EtOH with 0.45 g. (NH2)2.H2O let stand 15 min. and a few ml. H2O added gave Et 2-chloro-4-hydrazino-5-pyridinecarboxylate, m. 147-8°; 1 g. suspended in 30 mL. boiling H2O treated dropwise with 35 mL. 10% CuSO4 solution, refluxed 2.5 h., and steam-distilled gave 45-50% Et 2-chloro-5-pyridinecarboxylate (V), saponified to the acid, m. 195° (decomposition) (amide, m. 211°). V (0.25 g.) heated 4 h. at 110° in a sealed tube with 0.1 g. Na in 6 mL. MeOH, diluted with H2O, acidified, and evaporated halfway gave 2-methoxy-5-pyridinecarboxylic acid, m. 171.5-2.5° (from H2O). 2,4-Dichloro-5-pyridinecarboxylic acid (4 g.) and 2 mL. POCl3 warmed to 100°, treated with 13 g. PCl5, warmed 0.5 h. at 140°, evaporated under a vacuum, taken up in C6H6, and saturated with NH3 gave 95% nitrile, m. 136-7°; 0.5 g. with 0.5 mL. Br in 50 mL. 7% KOH at room temperature for a few hrs., then a few hrs. at 70°, acidified, made basic, and extracted with Et2O gave 30-40% 2,4-dichloro-5-aminopyridine (VI), m. 80-1° (from ligroin). VI (0.5 g.) in 10 mL. 38% HCl in an ice-salt bath treated with 1.05 g. NaNO2 in 3 mL. H2O, then with 2.2 g. Cu powder, and steam-distilled gave 40-50% 2,4,5-trichloropyridine (VII), m. 8.5-9° (from aqueous EtOH). Heating 0.1 g. VII 4 h. at 160° with 2 mL. NH4OH (d. 0.9) gave 2,5-dichloro-4-aminopyridine, m. 119-20°; 0.02 g. in 0.5 mL. 38% HCl treated with 0.08 g. H2O2 and evaporated gave 2,3,5-trichloro-4-aminopyridine, m. 147°. NaNO2 with 1 g. 2-chloro-3-aminopyridine gave 0.5 g. 2,3-dichloropyridine, m. 66.5-7°, which with concentrated NH4OH at 190° 36 h. gave 2-amino-3-chloropyridine (VIII), m. 61.5-2°. Heating 0.7 g. 2,4-dihydroxypyridine (IX) with 4 mL. POCl3 2.5 h. at 130-40° gave on making basic, steam-distilling, and extracting with Et2O 60-5% 2,4-di-Cl compound, m. -1 to 0°, b760 189-90°; 0.6 g. with 16 mL. NH4OH heated at 170-80° 4.5 h., made basic, extracted with Et2O, evaporated, and the residue fractionally extracted with 20 mL. ligroin gave 0.05 g. 2-amino-4-chloropyridine, m. 129-30° (picrate, m. 236-43°); after an addnl. extraction with 35 mL. ligroin giving 0.1 g. crystals, 0.1 g. residue remained from which 4-amino-2-chloropyridine, m. 91-1.5°, could be isolated by crystallization 4-Nitraminopyridine (1.8 g.) with 11 mL. 38% HCl heated 10 h. at 100°, made alk., and steam-distilled gave in the 1st fraction (20 mL.) a little 4-chloro- (soluble in dilute HCl), and 10% 3,4,5-trichloropyridine, m. 71.5-2.5°. The 2nd fraction (100 mL.) gave (0.4 g. 4-amino-3,5-dichloropyridine (X), m. 159.5-60.5°. Koenigs, Mields, and Gurlt (C.A. 19, 70) suggested that X was 3,4-dichloropyridine (XII). However, the structure of X was indicated by its isolation in 55-60% yield from 4-aminopyridine by chlorination with HC1 and also from 4-amino-3-chloropyridine (XI). Reduction of 4-chloro-3-nitropyridine with Fe powder and AcOH gave 70% 3-amino-4-chloropyridine, m. 59.5-60.5° (N-Ac derivative, m. 113-13.5°; picrate, m. 181-1.5°); diazotization as before gave XII, m. 23-3.5°, b760 182-3°. XII heated 10 h. at 190° with NH4OH gave XI, m. 60.5-1.5° [picrate, m. 227-9° (decomposition)]; 0.2 g. XII with 0.04 g. Na in 2 mL. EtOH heated 4 h. at 160° gave a residue of 0.175 g. oily 3-chloro-4-ethoxypyridine (picrate, m. 159.5-60°; picrolonate, m. 202-3°). II with HCl and H2O2 gave 70% Et 2,4-dihydroxy-3-chloro-5-pyridinecarboxylate,m. 257-8°; POCl3 then gave 60% Et 2,3,4-trichloro-5-pyridinecarboxylate, m. 34°, 0.07 g. of which was boiled 1.5 h. with 4 mL. 1% NaOH and the Ag salt heated to 230° in a stream of CO2 with distillation, giving 2,3,4-trichloropyridine (XIII), m. 45-6°. IX with HCl and H2O2 gave 3-chloro-2,4-dihydroxypyridine (XIV), decompose about 310°; 0.2 g. I with 5 mL. 38% HCl at 200° 3 h. also gave XIV which was converted to XIII. Et 3-bromo-2,4-dihydroxy-5-pyridinecarboxylate with HCl, then POCl3, gave XIII. 2-Amino-3-chloro-4-bromopyridine (0.14 g.) in 50 mL. EtOH with 0.1 g. NaOH and 10 mg. Pd-Norit catalyst gave impure 2-amino-3-chloropyridine (impure picrate, m. 232-3°). XIII with NH4OH gave by filtration and extraction with ligroin 2-amino-3,4-dichloropyridine, m. 93-5° (picrate, m. 234.5-7°); the crystals less soluble in ligroin were 2,3-dichloro-4-aminopyridine (XV), m. 153.5-4.5° (picrate, m. 198.5-9.5°). XV with HCl and H2O2 gave 2,3,5-trichloro-4-aminopyridine, m. 150-2°. 2,6-Dichloro-4-aminopyridine (XVI) diazotized gave 85% 2,4,6-trichloropyridine (XVII), m. 32.5-3°, b760 217.5-18.5°. XVII with NH4OH gave 2-amino-4,6-dichloro-pyridine (most soluble in ligroin), m. 112.5°, and XVI, m. 170.3°. XVII with NaOMe as before gave 70-5% 2,4,6-trimethoxypyridine, m. 47-8°, which was converted to the 3,5-di-Cl derivative, m. 95.5-6°. 2,4-Dichloro-3-nitropyridine, prepared in 75% yield from IX, was reduced with Fe and AcOH, giving 85-90% 3-amino compound (XVIII), m. 69-9.5° (N-Ac derivative, m. 161-2°). XVIII (0.75 g.) in 15 mL. AcOH saturated with HCl was mixed with 0.7 mL. 30% aqueous H2O2 in 3.3 mL. AcOH, heated 0.5 h. at 80°, and poured into NaOH and Na2SO3 in H2O, giving 3-amino-2,4,6-trichloropyridine (XIX), m. 77.5-8°, and XVIII. Diazotization of XIX gave 75% 2,3,4,6-tetrachloropyridine (XX), m. 37.5-8°, b760 248-9.5°. XVI chlorinated as for XVIII gave 4-amino-2,3,6-trichloropyridine, m. 160-0.5°, which was converted to XX. The substance m. 74-5° [Sell and Dootson, J. Chem. Soc. 73,432(1898)] obtained by the chlorination of pyridine was therefore not XX.

Recueil des Travaux Chimiques des Pays-Bas et de la Belgique published new progress about 14121-36-9. 14121-36-9 belongs to class pyridine-derivatives, and the molecular formula is C5HCl4N, Recommanded Product: 2,3,4,6-Tetrachloropyridine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Frolov, Nikita; Detusheva, Elena; Fursova, Nadezhda; Ostashevskaya, Irina; Vereshchagin, Anatoly published the artcile< Microbiological Evaluation of Novel Bis-Quaternary Ammonium Compounds: Clinical Strains, Biofilms, and Resistance Study>, Recommanded Product: 1-Hexadecylpyridin-1-ium chloride, the main research area is clin strains biofilms microbiologica novel bis quaternary ammonium compound; antibacterial activity; antibiofilm activity; antiseptics; bacterial resistance; biocides; disinfectants; pyridinium salts; quaternary ammonium compounds.

This work is devoted to the investigation of biocidal properties of quaternary ammonium compounds (QACs) based on pyridine structures with aromatic spacers, and their widely known analogs, against clin. significant microorganisms. This study is focused on investigating their antimicrobial activity (min. inhibitory concentrations (MICs) and min. bactericidal concentrations (MBCs)), antibiofilm properties (min. biofilm inhibitory concentrations (MBICs) and min. biofilm eradication concentrations (MBECs)), synergetic effect with different alcs. in antiseptic formulations, and bacterial resistance development. It was shown that all combined analog preparations had a higher level of antibacterial activity against the tested bacterial strains, with a 16- to 32-fold reduction in MICs and MBCs compared to previously used antiseptic preparations Moreover, hit-QACs demonstrated a stable effect against Gram-neg. E. coli, K. pneumoniae, and A. baumannii within a month of incubation. Overall results indicated a high level of antibacterial activity of pyridine-based QACs.

Pharmaceuticals published new progress about Acinetobacter baumannii. 123-03-5 belongs to class pyridine-derivatives, and the molecular formula is C21H38ClN, Recommanded Product: 1-Hexadecylpyridin-1-ium chloride.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Yang, Huan; Zhang, Li; Zhou, Fei-Yu; Jiao, Lei published the artcile< An umpolung approach to the hydroboration of pyridines: a novel and efficient synthesis of N-H 1,4-dihydropyridines>, Name: 3-(Methoxycarbonyl)pyridine, the main research area is diboron pyridine inverse hydroboration deuteration; dihydropyridine preparation.

The first inverse hydroboration of pyridine with a diboron compound and a proton source was realized under simple basic and catalyst-free conditions. This process consisted of a formal boryl anion addition to pyridine, which produced an N-boryl pyridyl anion complex and the subsequent protonation of the anion complex. This process enabled a simple and efficient method for the synthesis of multi-substituted N-H 1,4-dihydropyridine (1,4-DHP) derivatives that were difficult to prepare using established methods. Furthermore, this method allowed facile preparation of 4-deuterated 1,4-DHPs from an easily accessible deuterium ion source. This inverse hydroboration reaction represented a new mode for pyridine functionalization.

Chemical Science published new progress about Deuteration, regioselective. 93-60-7 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO2, Name: 3-(Methoxycarbonyl)pyridine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Allen, Jamie R.; Bahamonde, Ana; Furukawa, Yukino; Sigman, Matthew S. published the artcile< Enantioselective N-Alkylation of Indoles via an Intermolecular Aza-Wacker-Type Reaction>, SDS of cas: 1428537-19-2, the main research area is indolylalkanal chemoselective enantioselective preparation; chemoselective enantioselective aza Wacker reaction allylic homoallylic alc indole; enantioselective alkylation indole allylic homoallylic alc palladium catalyst; stereochem mechanism aza Wacker reaction deuterated allylic alc indole.

In the presence of Pd(MeCN)2(OTs)2 and a nonracemic pyridinyloxazoline, 3-substituted indoles such as 3-phenylindole underwent intermol., chemoselective, and enantioselective alkylation/aza-Wacker reactions with cis-allylic and cis-homoallylic alcs. such as (Z)-EtCH:CHCH2OH mediated by p-benzoquinone in 1,2-dichloroethane to yield nonracemic β- and γ-(1-indolyl)alkanals such as I; enamines generated under other conditions were not formed. The mechanism was studied using the reaction of a deuterium-labeled allylic alc.; the stereochem. of the product supported a syn amino-palladation mechanism for the reaction.

Journal of the American Chemical Society published new progress about Alcohols, homoallylic Role: RCT (Reactant), RACT (Reactant or Reagent). 1428537-19-2 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, SDS of cas: 1428537-19-2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Van Lommel, Ruben; Rutgeerts, Laurens A. J.; De Borggraeve, Wim M.; De Proft, Frank; Alonso, Mercedes published the artcile< Rationalising Supramolecular Hydrogelation of Bis-Urea-Based Gelators through a Multiscale Approach>, Application of C6H8N2, the main research area is urea gelator supramol hydrogelation density functional theory mol dynamics; aggregation; gels; molecular dynamics; noncovalent interactions; self-assembly.

The current approach to designing low-mol.-weight gelators relies on a laborious trial-and-error process, mainly because of the lack of an accurate description of the noncovalent interactions crucial for supramol. gelation. In this work, we report a multiscale bottom-up approach composed of several computational techniques to unravel the key interactions in a library of synthesized bis-urea-based gelators and rationalize their exptl. observed hydrogelation performance. In addition to d. functional theory calculations and mol. dynamics, the noncovalent interaction index is applied as a tool to visualise and identify the different types of noncovalent interactions. Interestingly, as well as hydrogen bonds between urea moieties, hydrogen bonds between a urea moiety and a pyridine ring were shown to play a detrimental role in the early aggregation phase. These findings enabled us to explain the hydrogelation performance observed in a library of twelve bis-urea derivatives, which were synthesized with 58-95 % yields. From this library, three compounds were discovered to effectively gel water, with the most efficient hydrogelator only requiring a concentration of 0.2 w/v%.

ChemPlusChem published new progress about Aggregation. 3731-53-1 belongs to class pyridine-derivatives, and the molecular formula is C6H8N2, Application of C6H8N2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Watanabe, Taiki; Sasabe, Hisahiro; Owada, Tsukasa; Maruyama, Tomohiro; Watanabe, Yuichiro; Katagiri, Hiroshi; Kido, Junji published the artcile< Chrysene-based Electron-transporters Realizing Highly Efficient and Stable Phosphorescent OLEDs>, Category: pyridine-derivatives, the main research area is chrysene electron transporter phosphorescence organic light emitting diode.

A series of chrysene-based electron-transporters named BnPyPCs (n = 2, 3, 4) end-capped with two 3,5-di(pyridin-n-yl)phenyl moieties with high thermal and elec. stability were successfully developed. BnPyPCs showed Tm values greater than 390°C and were used for highly efficient green phosphorescent OLEDs with maximum external quantum efficiency values greater than 20% and long operation lifetime at high brightness of approx. 11000 cd m-2 at a c.d. of 25 mA cm-2.

Chemistry Letters published new progress about Density functional theory. 329214-79-1 belongs to class pyridine-derivatives, and the molecular formula is C11H16BNO2, Category: pyridine-derivatives.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Chen, Tiffany Q.; Pedersen, P. Scott; Dow, Nathan W.; Fayad, Remi; Hauke, Cory E.; Rosko, Michael C.; Danilov, Evgeny O.; Blakemore, David C.; Dechert-Schmitt, Anne-Marie; Knauber, Thomas; Castellano, Felix N.; MacMillan, David W. C. published the artcile< Unified Approach to Decarboxylative Halogenation of (Hetero)aryl Carboxylic Acids>, Quality Control of 777931-67-6, the main research area is hetero aryl halide preparation photochem; aryl hetero carboxylic acid decarboxylative halogenation copper catalyst.

A general catalytic method for direct decarboxylative halogenation of (hetero)aryl carboxylic acids RC(O)OH (R = 4-sulfamoylphenyl, 5-methylpyridin-2-yl, isoquinolin-1-yl, etc.) via ligand-to-metal charge transfer was reported. This strategy accommodates an exceptionally broad scope of substrates. An aryl radical intermediate is leveraged toward divergent functionalization pathways: (1) atom transfer to access bromo- or iodo(hetero)arenes or (2) radical capture by copper and subsequent reductive elimination to generate chloro- or fluoro(hetero)arenes. The proposed ligand-to-metal charge transfer mechanism is supported through an array of spectroscopic studies.

Journal of the American Chemical Society published new progress about Aromatic carboxylic acids Role: RCT (Reactant), RACT (Reactant or Reagent). 777931-67-6 belongs to class pyridine-derivatives, and the molecular formula is C6H5BrClNO, Quality Control of 777931-67-6.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Watanabe, Hiroyuki; Tatsumi, Haruka; Kaide, Sho; Shimizu, Yoichi; Iikuni, Shimpei; Ono, Masahiro published the artcile< Structure-Activity Relationships of Radioiodinated 6,5,6-Tricyclic Compounds for the Development of Tau Imaging Probes>, Recommanded Product: 2-Bromo-N,N-dimethylpyridin-4-amine, the main research area is structure radioiodinated tricyclic compound Tau imaging probe.

Tau aggregate, which is the main component of the neurofibrillary tangle, is an attractive imaging target for diagnosing and monitoring the progression of Alzheimer’s disease (AD). In this study, we designed and synthesized six radioiodinated 6,5,6-tricyclic compounds to explore novel scaffolds for tau imaging probes. On in vitro autoradiog. of AD brain sections, pyridoimidazopyridine and benzimidazopyrimidine derivatives ([125I]21 and [125I]22, resp.) showed selective binding affinity for tau aggregates, whereas carbazole, pyrrolodipyridine, and pyridoimidazopyrimidine derivatives ([125I]10, [125I]12, and [125I]23, resp.) bound β-amyloid aggregates. In a biodistribution study using normal mice, [125I]21 and [125I]22 showed high initial uptakes (5.73 and 5.66% ID/g, resp., at 2 min postinjection) into and rapid washout (0.14 and 0.10% ID/g, resp., at 60 min postinjection) from the brain. Taken together, two novel scaffolds including pyridoimidazopyridine and benzimidazopyrimidine may be applied to develop useful tau imaging probes.

ACS Medicinal Chemistry Letters published new progress about Alzheimer disease (potential diagnosis). 396092-82-3 belongs to class pyridine-derivatives, and the molecular formula is C7H9BrN2, Recommanded Product: 2-Bromo-N,N-dimethylpyridin-4-amine.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem