Month: October 2022

Clark, Richard A. F. published the artcile< Oxidative Stress and ""Senescent"" Fibroblasts in Non-Healing Wounds as Potential Therapeutic Targets>, Formula: C7H5BrN2, the main research area is review oxidative stress senescent fibroblast nonhealing wound therapeutic target.

A review. In chronic wounds, fibroblast dysfunctions, such as increased apoptosis, premature senescence, senescence-like phenotype, or poor growth response in the absence of senescence markers, have been reported. Some of these differential dysfunctions may be secondary to differences in patient age or sex, ulcer size or duration, edge vs. base sampling, or culture technique. Nevertheless, the entire spectrum of fibroblast dysfunction may exist and be secondary to, or a response to, different amounts of oxidative stress. Journal of Investigative Dermatol. (2008) 128, 2361-2364. doi:10.1038/jid.2008.257.

Journal of Investigative Dermatology published new progress about Cell aging. 23612-36-4 belongs to class pyridine-derivatives, and the molecular formula is C7H5BrN2, Formula: C7H5BrN2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Ran, Wei; Liu, Xiaoyu; Chang, Lu; Cai, Ying; Zheng, Chao; Liu, Jia; Li, Yaping; Zhang, Pengcheng published the artcile< Self-assembling mertansine prodrug improves tolerability and efficacy of chemotherapy against metastatic triple-negative breast cancer>, Quality Control of 2127-03-9, the main research area is self assembling mertansine prodrug nanoparticle drug delivery system; Chemotherapy; Prodrug; Self-assembly; Supramolecular; Triple-negative breast cancer.

Metastatic triple-neg. breast cancer is one of the most devastating cancer types. Systemic chemotherapy is necessary, but its clin. performance is largely limited by severe side effects. Herein, we report a mertansine prodrug, which could self-assemble into spherical nanoparticles in water and readily convert into active mertansine at the presence of glutathione. The self-assembling mertansine prodrugs (SAMPDs) entered cancer cells via a caveolae-mediated pathway and exhibited potent cytotoxicity. The self-delivering SAMPDs did not cause hemolysis, and more importantly increased maximum tolerated dose (MTD) of mertansine by 8 folds via reducing free mertansine exposure in most of the major organs. SAMPDs improved intratumoral drug exposure and showed dose-dependent antitumor activity. When dosed at MTD, SAMPDs inhibited primary tumor growth and pulmonary metastasis by 80% and 95%, while mertansine dosed at MTD only reduced primary tumor growth and metastasis by <50% and 60%, resp. Our results reveal the mechanism of in vivo biotransformation of self-assembling prodrug and highlight the unique advantages of self-assembling prodrug strategy in improving the efficacy and safety of chemotherapy. Journal of Controlled Release published new progress about Antitumor agents. 2127-03-9 belongs to class pyridine-derivatives, and the molecular formula is C10H8N2S2, Quality Control of 2127-03-9.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Hameed P, Shahul; Raichurkar, Anandkumar; Madhavapeddi, Prashanti; Menasinakai, Sreenivasaiah; Sharma, Sreevalli; Kaur, Parvinder; Nandishaiah, Radha; Panduga, Vijender; Reddy, Jitendar; Sambandamurthy, Vasan K.; Sriram, D. published the artcile< Benzimidazoles: Novel Mycobacterial Gyrase Inhibitors from Scaffold Morphing>, Formula: C5H6FN3, the main research area is benzimidazole DNA gyrase inhibitor scaffold morphing Mycobacterium; DNA gyrase; NBTIs; Tuberculosis; aminopiperidines; benzimidazoles; type II topoisomerases.

Type II topoisomerases are well conserved across the bacterial species, and inhibition of DNA gyrase by fluoroquinolones has provided an attractive option for treatment of tuberculosis (TB). However, the emergence of fluoroquinolone-resistant strains of Mycobacterium tuberculosis (Mtb) poses a threat for its sustainability. A scaffold hopping approach using the binding mode of novel bacterial topoisomerase inhibitors (NBTIs) led to the identification of a novel class of benzimidazoles as DNA gyrase inhibitors with potent anti-TB activity. Docking of benzimidazoles to a NBTI bound crystal structure suggested that this class of compound makes key contacts in the enzyme active site similar to the reported NBTIs. This observation was further confirmed through the measurement of DNA gyrase inhibition, and activity against Mtb strains harboring mutations that confer resistance to aminopiperidines based NBTIs and Mtb strains resistant to moxifloxacin. Structure-activity relationship modification at the C-7 position of the left-hand side ring provided further avenue to improve hERG selectivity for this chem. series that has been the major challenges for NBTIs.

ACS Medicinal Chemistry Letters published new progress about DNA gyrases Role: BSU (Biological Study, Unclassified), BIOL (Biological Study) (inhibitors). 212268-13-8 belongs to class pyridine-derivatives, and the molecular formula is C5H6FN3, Formula: C5H6FN3.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Parvanak Boroujeni, Kaveh; Shojaei, Pegah published the artcile< Poly(4-vinylpyridine)-supported dual acidic ionic liquid: an environmentally friendly heterogeneous catalyst for the one-pot synthesis of 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols)>, Formula: C9H13NO3S, the main research area is sulfobutylpyridinium sulfate as catalyst Knoevenagel condensation Michael addition.

A poly(4-vinylpyridine)-supported Bronsted ionic liquid was easily prepared from its starting materials and used as a novel, highly efficient, and reusable heterogeneous catalytic system for the synthesis of 4,4′-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ol derivatives) by a condensation reaction between aromatic aldehydes and 2 equiv of 3-methyl-l-phenyl-5-pyrazolone. The synthesis of the target compound (catalyst) was achieved by a reaction of 1,2-oxathiane 2,2-dioxide (1,4-butanesultone) with 4-Vinylpyridine divinylbenzene copolymer and a subsequent anion exchange. The catalyst thus formed was a polymer-supported 1-(4-sulfobutyl)pyridinium sulfate ionic liquid The reaction products thus formed included 4,4′-(phenylmethylene)bis[3-methyl-1-phenyl-1H-pyrazol-5-ol] derivatives, a furan derivative [4,4′-[(2-furanyl)methylene]bis[3-methyl-1-phenyl-1H-pyrazolo-5-ol]], a thiophene derivative [4,4′-[(2-thienyl)methylene]bis[3-methyl-1-phenyl-1H-pyrazolo-5-ol]].

Turkish Journal of Chemistry published new progress about Addition reaction. 21876-43-7 belongs to class pyridine-derivatives, and the molecular formula is C9H13NO3S, Formula: C9H13NO3S.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

de Oliveira Silva, Juliana; Angnes, Ricardo A.; Menezes da Silva, Vitor H.; Servilha, Bruno M.; Adeel, Muhammad; Braga, Ataualpa A. C.; Aponick, Aaron; Correia, Carlos Roque D. published the artcile< Intermolecular Noncovalent Hydroxy-Directed Enantioselective Heck Desymmetrization of Cyclopentenol: Computationally Driven Synthesis of Highly Functionalized cis-4-Arylcyclopentenol Scaffolds>, SDS of cas: 1416819-91-4, the main research area is cyclopentenol aryldiazonium palladium chiral dihydrooxazole enantioselective Heck desymmetrization catalyst; arylcyclopentenol stereoselective preparation.

New computationally driven protocols for the Heck desymmetrization of 3-cyclopenten-1-ol with aryldiazonium tetrafluoroborates were developed. These new conditions furnished remarkable product selectivity originating from a resident hydroxyl group and the critical choice of the reaction solvent. Mechanistic insights gleaned from theor. calculations of the putative transition states predicted toluene as an adequate solvent choice to attain high enantioselectivity by strengthening the noncovalent interaction of the substrate hydroxyl group and the chiral cationic palladium catalyst. Laboratory experiments validated the theor. predictions, and by employing 2% MeOH/toluene as solvent, the Heck-Matsuda reaction provided exclusively the cis-4-arylcyclopentenols in good to excellent yields in enantiomeric excesses up to 99%. The performance of the new PyOx ligand (S)-4-tert-butyl-2-(3,5-dichloropyridin-2-yl)-4,5-dihydrooxazole was also successfully evaluated in the Heck-Matsuda desymmetrization of 3-cyclopenten-1-ol. The synthetic potential of these highly functionalized cis-4-arylcyclopentenols is illustrated by a gold-catalyzed synthesis of cyclopenta[b]benzofuran skeletons.

Journal of Organic Chemistry published new progress about Chiral ligands Role: CAT (Catalyst Use), SPN (Synthetic Preparation), USES (Uses), PREP (Preparation). 1416819-91-4 belongs to class pyridine-derivatives, and the molecular formula is C13H15F3N2O, SDS of cas: 1416819-91-4.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Kooyman, E. C.; Wibaut, J. P. published the artcile< Pyridine and quinoline derivatives. LX. The orientation of the CO2C2H5 group in the condensation product of malonic ester and β-aminocrotonic acid ester>, Product Details of C9H9Cl2NO2, the main research area is .

In the 2-methyl-4,6-dihydroxypyridinecarboxylate described by Knoevenagel and Fries (Ber. 31, 767(1898)), the position of the carboxylate group was unknown. The location of this group at 5 rather than at 3 was established by the following reactions: The original condensation product, heated with POCl3 at 120° in a sealed tube for 4 hrs., yielded a mixture of the acid chloride (I) and the Et ester (II) of 2-methyl-4,6-dichloro-5-pyridinecarboxylic acid, which could be separated by fractional distillation at 1 mm. The first fraction b. 97-104°, and after a 2nd distillation was obtained as a clear, colorless oil which solidified at 14.8°. The analyses agreed fairly well with C7H4ONCl3. On heating with H2O, HCl was split off, and the free acid was obtained. The compound was therefore believed to be I. The 2nd fraction b. 113-16°. It was obtained in 30% yield as white needles, m. 56° (50% EtOH), which were readily soluble in Et2O and EtOH, and sparingly soluble in H2O. It was identified as II. The free acid obtained from the ester by saponification m. 151.5° (dilute HCl) and was slightly soluble in H2O, very slightly soluble in HCl, but readily soluble in Et2O and EtOH. By catalytic reduction of II in absolute EtOH with Pd chloride and KOAc, the Cl was removed, and Et 2-methyl-5-pyridinecarboxylate (III) was obtained in 72% yield as a colorless oil b2 97° (Graf, C.A. 26, 1932). By saponification of III with KOH, preparation of the Cu salt, and decomposition with H2S, the free acid (IV) was obtained. It was purified by sublimation at 180°/35 mm. and m. 209-10°. It was identified by mixed m.p. with a sample prepared from 2-methyl-5-ethylpyridine. The amide (V), m. 196°, was prepared from III by shaking with NH3 according to the method of Graf. The picrate of the ester m. 170-1° (light yellow needles from alc. picric acid). The amide and the picrate showed no m.p. depression when mixed with the corresponding amide and picrate prepared from the ester obtained from 2-methyl-5-ethylpyridine.

Recueil des Travaux Chimiques des Pays-Bas et de la Belgique published new progress about 86129-63-7. 86129-63-7 belongs to class pyridine-derivatives, and the molecular formula is C9H9Cl2NO2, Product Details of C9H9Cl2NO2.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Maegawa, Tomohiro; Oishi, Ryohei; Maekawa, Ayumi; Segi, Kazutoshi; Hamamoto, Hiromi; Nakamura, Akira; Miki, Yasuyoshi published the artcile< The Reaction of Ketoximes with Hypervalent Iodine Reagents: Beckmann Rearrangement and Hydrolysis to Ketones>, Quality Control of 350-03-8, the main research area is ketoxime hypervalent iodine Beckmann rearrangement; amide preparation; oxime hypervalent iodine reagent hydrolysis; ketone preparation.

The reaction of ketoximes with hypervalent iodine reagents was investigated. A combination of PhI(OAc) 2 and BF3·Et2O promoted the Beckmann rearrangement of ketoximes, thus yielding the corresponding amides. From a detailed investigation of the reaction, it was determined that the Beckmann rearrangement is preceded by acetylation of the hydroxy group of the ketoxime in situ, accelerating the Beckmann rearrangement. The acetylated ketoxime undergoes the Beckmann rearrangement with BF3·Et2O was confirmed. The reaction of ketoximes with Koser’s reagent [PhI(OH)OTs] in the presence of THF results in hydrolysis, affording the corresponding ketones in high yields at room temperature

Synthesis published new progress about Amides Role: SPN (Synthetic Preparation), PREP (Preparation). 350-03-8 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO, Quality Control of 350-03-8.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Omidvar, Rose; Wu, Shijian; Mohammadigoushki, Hadi published the artcile< Detecting wormlike micellar microstructure using extensional rheology>, Name: 1-Hexadecylpyridin-1-ium chloride, the main research area is wormlike micellar microstructure rheol.

We report experiments on two series of wormlike micellar solutions that comprise octyl trimethylammonium bromide/sodium oleate (OTAB/NaOA) and cetylpyridinium chloride/sodium salicylate (CPCl/NaSal) using a capillary breakup extensional rheometer (CaBER) and a dripping onto substrate (DoS) technique. These wormlike micellar systems show a peak in zero shear viscosity or in the shear relaxation time beyond a critical surfactant or salt concentration Prior cryogenic transmission electron microscopy imaging has indicated that the system based on OTAB/NaOA experiences a transition from linear to shorter linear micelles (L-L) beyond the viscosity peak. However, the linear wormlike micelles based on CPCl/NaSal form branched networks beyond the viscosity peak (L-B). In this work, we investigate whether the extensional rheol. is sensitive to these two different microstructural transitions. In particular, we attempt to develop a criterion based on the extensional flow parameters in order to distinguish these two systems from each other. In addition, we probe the possibility of flow-induced micellar breakage imposed by capillary breakup extensional experiments Our results indicate that at a given zero shear viscosity, the branched wormlike micelles based on CPCl/NaSal exhibit a longer filament lifetime tfil than the linear wormlike micelles. However, beyond the critical concentration, the linear wormlike micelles based on OTAB/NaOA exhibit significantly shorter filament lifetimes than their linear counterparts at concentrations below the viscosity peak. More importantly, we show that the filament lifetime scales differently with zero shear viscosity η0 in these two systems. For L-B transition, tfilαη01.1 below the viscosity peak and tfilαη00.76above the viscosity peak. However, for L-L transition, this scaling remains the same for concentrations below and above the viscosity peak and reads as tfilαη00.5. These findings provide a novel criterion to distinguish these two types of microstructural transitions in wormlike micelles. On the other hand, we demonstrate that the Trouton ratio, filament lifetime, and the extensional relaxation time measured by CaBER technique are all lower than the ones obtained by DoS method. The latter result provides the first evidence for strong nonlinear effects (e.g., flow-induced micellar breakage) in capillary breakup extensional flows of wormlike micelles. (c) 2019 American Institute of Physics.

Journal of Rheology (Melville, NY, United States) published new progress about Dimensionless number, Weissenberg. 123-03-5 belongs to class pyridine-derivatives, and the molecular formula is C21H38ClN, Name: 1-Hexadecylpyridin-1-ium chloride.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Zhang, Jiang; Chen, Xu-Feng; Huang, Wei-Tao; Chen, Huan-Huan; Lai, Ning-Wei; Yang, Lin-Tong; Huang, Zeng-Rong; Guo, Jiuxin; Ye, Xin; Chen, Li-Song published the artcile< Mechanisms for increased pH-mediated amelioration of copper toxicity in Citrus sinensis leaves using physiology, transcriptomics and metabolomics>, Quality Control of 93-60-7, the main research area is copper Citrus leaf toxicity transcriptomic metabolomic.

Limited data are available on the mol. and physiol. mechanisms for increased pH-mediated amelioration of copper (Cu) toxicity in plants. Citrus sinensis seedlings were fertilized with a nutrient solution at the Cu concentration of 300 (Cu toxicity) or 0.5μM (control) and a pH of 3.0, 4.0, or 4.8 for 17 wk. Subsequently, we examined the interactive effects of low pH and Cu toxicity on transcriptomics, metabolomics, and some physiol. parameters in leaves. Our results demonstrated that increased pH reduced Cu toxicity-induced leaf Cu accumulation and oxidative damage by reducing reactive oxygen species (ROS) production and maintaining the homeostasis of sulfur (S)-containing compounds (reduced glutathione), ascorbate, and cell redox potential, thus mitigating Cu toxic effects on leaf chlorophyll biosynthesis, photosynthesis, and metabolisms of carbohydrates, lipids, amino acids, and secondary metabolites. The increased pH mitigated Cu toxicity-induced impairment of cell wall metabolism by reducing cell wall Cu concentration, thus improving leaf growth. Under low pH (pH 3.0), C. sinensis leaves also displayed some adaptive responses to Cu toxicity to meet the increased demand for the dissipation of excess light energy and the detoxification of Cu and ROS, including: (a) increased distribution of Cu in cell wall; (b) elevated photorespiration and thermal dissipation. And increased accumulation of nonstructural carbohydrates [fructose, glucose, starch, total nonstructural carbohydrates (the summation of fructose + glucose + sucrose + starch), maltotetraose and 1,1-kestotetraose] and upregulation of metabolism (glycolysis/gluconeogenesis, pyruvate metabolism and pentose phosphate pathway) related to energy production; (d) downregulation of phospholipid [LysoPC 18:3(2 n isomer)] and phosphate-containing compounds (2′-deoxycytidine-5′-monophosphate and AMP) and upregulation of -tryptophan metabolism and related amino acids (-tryptophan and 5-hydroxy–tryptophan); and (e) increased accumulation of some secondary metabolites [total phenolics, lignin, alkaloids (3-indoleacrylic acid, N-acetyl-5-hydroxytryptamine and Me nicotinate), plumerane (indole and 3-indolepropionic acid) and coumarins (isoscopoletin, scopoletin, skimming and scopolin)]. However, these adaptive responses could not protect low pH-treated leaves from Cu toxicity, as indicated by elevated malondialdehyde accumulation and electrolyte leakage and decreased photosynthesis and chlorophyll level in leaves as well as reduced leaf growth due to impaired cell metabolism Cu toxicity intensified the adverse effects of low pH on C. sinensis leaves.

Environmental and Experimental Botany published new progress about Amino acids Role: BSU (Biological Study, Unclassified), BIOL (Biological Study). 93-60-7 belongs to class pyridine-derivatives, and the molecular formula is C7H7NO2, Quality Control of 93-60-7.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Anantoju, Kishore Kumar; Tharikoppula, Giri; Eppakayala, Laxminarayana; Maringanti, Thirumala Chary published the artcile< A facile synthesis of methyl-2-(N-ethyl-N-phenylamino)naphthyridine-3-carboxylates>, Product Details of C6H6N2O, the main research area is pyridinecarboxaldehyde amino malonamide Friedlander condensation heterocyclization; naphthyridine carboxylic acid preparation esterification; phenylamino naphthyridine carboxylate preparation.

An efficient protocol for the synthesis of Me 2-(N-ethyl-N-phenylamino)naphthyridine-3-carboxylates I (X = N, Y = Z = CH; Y = N, X = Z = CH; Z = N, X = Y = CH) was developed. The methodol. is cost effective and provided an efficient alternative to existing methods for the synthesis of 2-substituted naphthyridine-3-carboxylic acids.

International Journal of Chemical and Analytical Science published new progress about Aminals Role: RCT (Reactant), RACT (Reactant or Reagent). 55279-29-3 belongs to class pyridine-derivatives, and the molecular formula is C6H6N2O, Product Details of C6H6N2O.

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem