Day: November 22, 2022

One-carbon metabolism in children with marasmus and kwashiorkor was written by May, Thaddaeus;de la Haye, Bethany;Nord, Gabrielle;Klatt, Kevin;Stephenson, Kevin;Adams, Sara;Bollinger, Lucy;Hanchard, Neil;Arning, Erland;Bottiglieri, Teodoro;Maleta, Kenneth;Manary, Mark;Jahoor, Farook. And the article was included in EBioMedicine in 2022.Application In Synthesis of (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate The following contents are mentioned in the article:

Kwashiorkor is a childhood syndrome of edematous malnutrition. Its precise nutritional precipitants remain uncertain despite nine decades of study. Remarkably, kwashiorkors disturbances resemble the effects of exptl. diets that are deficient in one-carbon nutrients. This similarity suggests that kwashiorkor may represent a nutritionally mediated syndrome of acute one-carbon metabolism dysfunction. Here we report findings from a cross-sectional exploration of serum one-carbon metabolites in Malawian children. Blood was collected from children aged 12-60 mo before nutritional rehabilitation: kwashiorkor (N = 94), marasmic-kwashiorkor (N = 43) marasmus (N = 118), moderate acute malnutrition (N = 56) and controls (N = 46). Serum concentrations of 16 one-carbon metabolites were quantified using LC/MS techniques, and then compared across participant groups. Twelve of 16 measured one-carbon metabolites differed significantly between participant groups. Measured outputs of one-carbon metabolism, asym. dimethylarginine (ADMA) and cysteine, were lower in marasmic-kwashiorkor (median μmol/L (± SD): 0·549 (± 0·217) P = 0·00045 & 90 (± 40) P < 0·0001, resp.) and kwashiorkor (0·557 (± 0·195) P < 0·0001 & 115 (± 50) P < 0·0001), relative to marasmus (0·698 (± 0·212) & 153 (± 42)). ADMA and cysteine were well correlated with methionine in both kwashiorkor and marasmic-kwashiorkor. Kwashiorkor and marasmic-kwashiorkor were distinguished by evidence of one-carbon metabolism dysfunction. Correlative observations suggest that methionine deficiency drives this dysfunction, which is implicated in the syndromes pathogenesis. The hypothesis that kwashiorkor can be prevented by fortifying low quality diets with methionine, along with nutrients that support efficient methionine use, such as choline, requires further investigation. The Hickey Family Foundation, the American College of Gastroenterol., the NICHD, and the USDA/ARS. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Application In Synthesis of (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Pyridine derivatives are also useful as small-molecule α-helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.Application In Synthesis of (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

One-carbon metabolism in children with marasmus and kwashiorkor was written by May, Thaddaeus;de la Haye, Bethany;Nord, Gabrielle;Klatt, Kevin;Stephenson, Kevin;Adams, Sara;Bollinger, Lucy;Hanchard, Neil;Arning, Erland;Bottiglieri, Teodoro;Maleta, Kenneth;Manary, Mark;Jahoor, Farook. And the article was included in EBioMedicine in 2022.Formula: C8H10NO6P The following contents are mentioned in the article:

Kwashiorkor is a childhood syndrome of edematous malnutrition. Its precise nutritional precipitants remain uncertain despite nine decades of study. Remarkably, kwashiorkors disturbances resemble the effects of exptl. diets that are deficient in one-carbon nutrients. This similarity suggests that kwashiorkor may represent a nutritionally mediated syndrome of acute one-carbon metabolism dysfunction. Here we report findings from a cross-sectional exploration of serum one-carbon metabolites in Malawian children. Blood was collected from children aged 12-60 mo before nutritional rehabilitation: kwashiorkor (N = 94), marasmic-kwashiorkor (N = 43) marasmus (N = 118), moderate acute malnutrition (N = 56) and controls (N = 46). Serum concentrations of 16 one-carbon metabolites were quantified using LC/MS techniques, and then compared across participant groups. Twelve of 16 measured one-carbon metabolites differed significantly between participant groups. Measured outputs of one-carbon metabolism, asym. dimethylarginine (ADMA) and cysteine, were lower in marasmic-kwashiorkor (median μmol/L (± SD): 0·549 (± 0·217) P = 0·00045 & 90 (± 40) P < 0·0001, resp.) and kwashiorkor (0·557 (± 0·195) P < 0·0001 & 115 (± 50) P < 0·0001), relative to marasmus (0·698 (± 0·212) & 153 (± 42)). ADMA and cysteine were well correlated with methionine in both kwashiorkor and marasmic-kwashiorkor. Kwashiorkor and marasmic-kwashiorkor were distinguished by evidence of one-carbon metabolism dysfunction. Correlative observations suggest that methionine deficiency drives this dysfunction, which is implicated in the syndromes pathogenesis. The hypothesis that kwashiorkor can be prevented by fortifying low quality diets with methionine, along with nutrients that support efficient methionine use, such as choline, requires further investigation. The Hickey Family Foundation, the American College of Gastroenterol., the NICHD, and the USDA/ARS. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Formula: C8H10NO6P).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. Pyridine groups exist in countless molecules, and their applications include catalysis, drug design, molecular recognition, and natural product synthesis.Formula: C8H10NO6P

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Associations of Serum Vitamin B6 Status and Catabolism With All-Cause Mortality in Patients With T2DM. was written by Zhang, Dandan;Li, Yilan;Lang, Xueyan;Zhang, Yao. And the article was included in The Journal of clinical endocrinology and metabolism in 2022.Application of 54-47-7 The following contents are mentioned in the article:

CONTEXT: There is little evidence regarding the association between serum vitamin B6 status and catabolism and all-cause mortality in patients with type-2 diabetes mellitus (T2DM). OBJECTIVE: We aimed to ascertain if the serum level of vitamin B6 and catabolism, including pyridoxal 5′-phosphate (PLP) and 4-pyridoxic acid (4-PA), were associated with risk of all-cause mortality in T2DM patients. METHODS: This prospective cohort study involved 2574 patients with T2DM who participated in the National Health and Nutrition Examination Survey (NHANES) from 2005 to 2010. The serum concentrations of PLP and 4-PA were used to assess the serum level of vitamin B6. Mortality status was determined by routine follow-up using the National Death Index through December 31, 2015. RESULTS: Over a median follow-up of 85 months, there were 588 deaths. The fully adjusted Cox model indicated that the highest serum PLP concentrations (> 63.6 nmol/L) were associated with a decrease in all-cause mortality (hazard ratio [HR], 0.74; 95% CI, 0.55-0.99, P trend = .035). The risk for all-cause mortality was 59% higher for participants with the highest quartile of 4-PA level compared with the lowest quartile (HR, 1.62; 95% CI, 1.12-2.35; P trend = .003). The sensitivity and specificity of the combination of PLP and 4-PA levels for the prediction of all-cause mortality were 59.5% and 60.9%, respectively (area under the receiver operating characteristic curve = 0.632). The Kaplan-Meier method was used to estimate overall survival for patients based on different combinations of PLP level and 4-PA level. Patients with PLP less than 24.3 nmol/L and 4-PA greater than or equal to 25.4 nmol/L had the worst outcomes (log-rank P < .001). CONCLUSION: Overall, our data suggest that a low serum level of PLP and high serum level of 4-PA, which represent the serum level of vitamin B6, increases the risk of all-cause mortality significantly in patients with T2DM. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Application of 54-47-7).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Application of 54-47-7

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

XAD-2-A useful alternative to Tenax TA for analysis of biogenic volatiles employing thermal desorption coupled with gas chromatography-mass spectrometry was written by Marcillo, Andrea;Jakimovska, Viktorija;Widdig, Anja;Birkemeyer, Claudia. And the article was included in Journal of Chromatography A in 2017.Application In Synthesis of 2,3,4,5,6-Perfluoropyridine The following contents are mentioned in the article:

Volatile organic compounds (VOCs) are commonly collected from gaseous samples by adsorption to materials such as the porous polymer Tenax TA. Adsorbed compounds are subsequently released from these materials by thermal desorption (TD) and separated then by gas chromatog. (GC) with flame ionization (FID) or mass spectrometry (MS) detection. Tenax TA is known to be particularly suitable for nonpolar to semipolar volatiles, however, many volatiles from environmental and biol. samples possess a rather polar character. Therefore, the authors tested if the polymer XAD-2, which so far is widely used to adsorb organic compounds from aqueous and organic solvents, could provide a broader coverage for (semi)polar VOCs during gas-phase sampling. Mixtures of volatile compounds covering a wide range of volatility (b.p. 20-256°) and different chem. classes were introduced by liquid spiking into sorbent tubes with one of the two porous polymers, Tenax TA or XAD-2, and analyzed by TD/GC-MS. At 1st, an internal standard mixture composed of 17 authentic standards was used to optimize desorption temperature with respect to sorbent degradation and loading time for calibration. Secondly, the authors tested the detectability of a complex standard mixture composed of 57 volatiles, most of them common constituents of the body odor of mammals. Also, the performance of XAD-2 compared with Tenax TA was assessed as limit of quantitation and linearity for the internal standard mixture and 33 compounds from the complex standard mixture Volatiles were analyzed in a range between 0.01-∼250 ng/tube depending on the compound and material. Lower limits of quantitation were 0.01-3 ng ± <25% relative standard deviation (R² > 0.9). The authors found different kinetics for compound adsorption with XAD-2, and a partially better sensitivity in comparison with Tenax TA. For these analytes, XAD-2 might be recommended as an alternative of Tenax TA for TD/GC-MS anal. This study involved multiple reactions and reactants, such as 2,3,4,5,6-Perfluoropyridine (cas: 700-16-3Application In Synthesis of 2,3,4,5,6-Perfluoropyridine).

2,3,4,5,6-Perfluoropyridine (cas: 700-16-3) belongs to pyridine derivatives. Pyridines are an important class of heterocycles and occur in polysubstituted forms in many naturally occurring biologically active compounds, drug molecules and chiral ligands. Many analogues of pyridine are known where N is replaced by other heteroatoms . Substitution of one C–H in pyridine with a second N gives rise to the diazine heterocycles (C4H4N2), with the names pyridazine, pyrimidine, and pyrazine.Application In Synthesis of 2,3,4,5,6-Perfluoropyridine

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Computational Analysis on the Allostery of Tryptophan Synthase: Relationship between α/β-Ligand Binding and Distal Domain Closure was written by Ito, Shingo;Yagi, Kiyoshi;Sugita, Yuji. And the article was included in Journal of Physical Chemistry B in 2022.Safety of (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate The following contents are mentioned in the article:

Tryptophan synthase (TRPS) is a bifunctional enzyme consisting of α and β-subunits and catalyzes the last two steps of L-tryptophan (L-Trp) biosynthesis, namely, cleavage of 3-indole-D-glycerol-3′-phosphate (IGP) into indole and glyceraldehyde-3-phosphate (G3P) in the α-subunit, and a pyridoxal phosphate (PLP)-dependent reaction of indole and L-serine (L-Ser) to produce L-Trp in the β-subunit. Importantly, the IGP binding at the α-subunit affects the β-subunit conformation and its ligand-binding affinity, which, in turn, enhances the enzymic reaction at the α-subunit. The intersubunit communications in TRPS have been investigated extensively for decades because of the fundamental and pharmaceutical importance, while it is still difficult to answer how TRPS allostery is regulated at the at. detail. Here, we investigate the allosteric regulation of TRPS by all-atom classical mol. dynamics (MD) simulations and analyze the potential of mean-force (PMF) along conformational changes of the α- and β-subunits. The present simulation has revealed a widely opened conformation of the β-subunit, which provides a pathway for L-Ser to enter into the β-active site. The IGP binding closes the α-subunit and induces a wide opening of the β-subunit, thereby enhancing the binding affinity of L-Ser to the β-subunit. Structural analyses have identified critical hydrogen bonds (HBs) at the interface of the two subunits (αG181-βS178, αP57-βR175, etc.) and HBs between the β-subunit (βT110 – βH115) and a complex of PLP and L-Ser (an α-aminoacrylate intermediate). The former HBs regulate the allosteric, β-subunit opening, whereas the latter HBs are essential for closing the β-subunit in a later step. The proposed mechanism for how the interdomain communication in TRPS is realized with ligand bindings is consistent with the previous exptl. data, giving a general idea to interpret the allosteric regulations in multidomain proteins. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Safety of (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Safety of (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Computational Analysis on the Allostery of Tryptophan Synthase: Relationship between α/β-Ligand Binding and Distal Domain Closure was written by Ito, Shingo;Yagi, Kiyoshi;Sugita, Yuji. And the article was included in Journal of Physical Chemistry B in 2022.Synthetic Route of C8H10NO6P The following contents are mentioned in the article:

Tryptophan synthase (TRPS) is a bifunctional enzyme consisting of α and β-subunits and catalyzes the last two steps of L-tryptophan (L-Trp) biosynthesis, namely, cleavage of 3-indole-D-glycerol-3′-phosphate (IGP) into indole and glyceraldehyde-3-phosphate (G3P) in the α-subunit, and a pyridoxal phosphate (PLP)-dependent reaction of indole and L-serine (L-Ser) to produce L-Trp in the β-subunit. Importantly, the IGP binding at the α-subunit affects the β-subunit conformation and its ligand-binding affinity, which, in turn, enhances the enzymic reaction at the α-subunit. The intersubunit communications in TRPS have been investigated extensively for decades because of the fundamental and pharmaceutical importance, while it is still difficult to answer how TRPS allostery is regulated at the at. detail. Here, we investigate the allosteric regulation of TRPS by all-atom classical mol. dynamics (MD) simulations and analyze the potential of mean-force (PMF) along conformational changes of the α- and β-subunits. The present simulation has revealed a widely opened conformation of the β-subunit, which provides a pathway for L-Ser to enter into the β-active site. The IGP binding closes the α-subunit and induces a wide opening of the β-subunit, thereby enhancing the binding affinity of L-Ser to the β-subunit. Structural analyses have identified critical hydrogen bonds (HBs) at the interface of the two subunits (αG181-βS178, αP57-βR175, etc.) and HBs between the β-subunit (βT110 – βH115) and a complex of PLP and L-Ser (an α-aminoacrylate intermediate). The former HBs regulate the allosteric, β-subunit opening, whereas the latter HBs are essential for closing the β-subunit in a later step. The proposed mechanism for how the interdomain communication in TRPS is realized with ligand bindings is consistent with the previous exptl. data, giving a general idea to interpret the allosteric regulations in multidomain proteins. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Synthetic Route of C8H10NO6P).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. The pyridine ring occurs in many important compounds, including agrochemicals, pharmaceuticals, and vitamins. Pyridine derivatives are also useful as small-molecule α-helix mimetics that inhibit protein-protein interactions, as well as functionally selective GABA ligands.Synthetic Route of C8H10NO6P

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

The identification and application of a robust ω-transaminase with high tolerance towards substrates and isopropylamine from a directed soil metagenome was written by Xie, Youyu;Wang, Jiguo;Yang, Lin;Wang, Wei;Liu, Qinghai;Wang, Hualei;Wei, Dongzhi. And the article was included in Catalysis Science & Technology in 2022.Application of 54-47-7 The following contents are mentioned in the article:

ω-Transaminase-mediated asym. amination of a ketone substrate has gained significant attention for its immense potential to synthesize chiral amine pharmaceuticals and precursors. However, few of these have been authentically applied in industry due to inherent limitations such as low catalytic efficiency, unfavorable equilibrium, and poor tolerance towards high concentrations of substrate and isopropylamine (IPA). In this study, by specially screening a metagenomic library from amidogen-enriched environments established to retrieve class III transaminases, a robust ω-transaminase, ATA1012, was identified that exhibited high industrial potential. First, it showed relative stability at 30-50 °C and even at 30 °C for 800 h with residual activity >50%, which greatly benefits a continuous industrial process operation. Second, it was capable of tolerating IPA concentrations as high as 2 M. IPA is one of the most industrially favored amine donors because it is inexpensive and achiral; however, it is not widely accepted by most ω-transaminases. Third, it also showed high substrate tolerance towards the target ketones 1-Boc-3-piperidone (2t) and 1-Boc-3-pyrrolidone (2s) at concentrations up to 750 mM, and 2 IPA equivalent were sufficient to efficiently shift the equilibrium to the desired production side with up to 100% conversion. After systematic optimization of the reaction parameters, including the substrate loading, reaction temperature, IPA dosage and pyridoxal-5′-phosphate (PLP) concentration in the amination process, up to 0.75 M 1-Boc-3-piperidone (2t) (150 g L-1) and 1-Boc-3-pyrrolidone (2s) (139 g L-1) were efficiently converted to the corresponding chiral amines with ee values of >99.9% in 12 h. The hectogram reaction process was readily scaled up, producing a green productive amination process for the efficient production of chiral amines. The mol. basis of the outstanding catalytic efficiency of ATA1012 was also elucidated by mol. docking and mol. dynamics anal. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Application of 54-47-7).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. Pyridine has a conjugated system of six π electrons that are delocalized over the ring. The molecule is planar and, thus, follows the Hückel criteria for aromatic systems. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Application of 54-47-7

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Common and novel metabolic pathways related ESTs were upregulated in three date palm cultivars to ameliorate drought stress was written by Alhajhoj, Mohammed Refdan;Munir, Muhammad;Sudhakar, Balakrishnan;Ali-Dinar, Hassan Muzzamil;Iqbal, Zafar. And the article was included in Scientific Reports in 2022.Synthetic Route of C8H10NO6P The following contents are mentioned in the article:

Date palm is an important staple crop in Saudi Arabia, and about 400 different date palm cultivars grown here, only 50-60 of them are used com. The most popular and com. consumed cultivars of these are Khalas, Reziz, and Sheshi, which are also widely cultivated across the country. Date palm is high water-demanding crop in oasis agriculture, with an inherent ability to tolerate drought stress. However, the mechanisms by which it tolerates drought stress, especially at the transcriptomic level, are still elusive. This study appraised the physiol. and mol. response of three com. date palm cultivars Khalas, Reziz, and Sheshi at two different field capacities (FC; 100% and 25%) levels. At 25% FC (drought stress), leaf relative water content, chlorophyll, photosynthesis, stomatal conductance, and transpiration were significantly reduced. However, leaf intercellular CO2 concentration and water use efficiency increased under drought stress. In comparison to cvs.Khalas and Reziz, date palm cv.Sheshi showed less tolerance to drought stress. A total of 1118 drought-responsive expressed sequence tags (ESTs) were sequenced, 345 from Khalas, 391 from Reziz, and 382 from Sheshi and subjected to functional characterization, gene ontol. classification, KEGG pathways elucidation, and enzyme codes dissemination. Three date palm cultivars deployed a multivariate approach to ameliorate drought stress by leveraging common and indigenous mol., cellular, biol., structural, transcriptional and reproductive mechanisms. Approx. 50% of the annotated ESTs were related to photosynthesis regulation, photosynthetic structure, signal transduction, auxin biosynthesis, osmoregulation, stomatal conductance, protein synthesis/turnover, active transport of solutes, and cell structure modulation. Along with the annotated ESTs, ca. 45% of ESTs were novel. Conclusively, the study provides novel clues and opens the myriads of genetic resources to understand the fine-tuned drought amelioration mechanisms in date palm. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Synthetic Route of C8H10NO6P).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. 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). Pyridine, its benzo and pyridine-based compounds play diverse roles in organic chemistry. Pyridine-based materials are valued for their optical and physical properties as well as their medical potential. Synthetic Route of C8H10NO6P

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Optically active amines. XIV. Circular dichroism of 1-(2-, 3-, and 4-pyridyl)ethylamine and some related compounds was written by Smith, Howard E.;Schaad, L. J.;Banks, R. Bruce;Wiant, Christopher J.;Jordan, Charles F.. And the article was included in Journal of the American Chemical Society in 1973.Reference of 40154-80-1 The following contents are mentioned in the article:

Resolution with tartaric acid gave (S)-(-)-1-(2-, 3-, and 4-pyridyl)ethylamine and (R)-(+)-1-(3-pyridyl)ethylamine (I). The uv (isotropic absorption) and CD spectra of (S)-(+)-N-salicylidene-1-(2-pyridyl)ethylamine and (S)-(+)-N-(5-bromosalicylidene)-1-(4-pyridyl)ethylamine were examined These are similar to those of (S)-(+)-N-salicylidene-α-phenylethylamine, indicating that the CD spectra of such Schiff base derivatives may also be used for the establishment of the absolute configurations of chiral pyridyl-substituted alkylamines. 1-(4-Pyridyl)ethylamine on storage forms N-[1-(4-pyridyl)ethylidene]-1-(4-pyridyl)ethylamine by light-catalyzed oxidative process. For this reason, the racemic and optically active amines were converted to their resp. dihydrochlorides. The uv spectrum of each amine in 0.1M KOHMeOH shows an absorption maximum near 260 nm flanked by shoulders near 255 and 265 nm. These extrema are assigned to the π → π* (1Lb) transition of the pyridyl chromophore. Corresponding to each of these uv extrema, a pos. maximum is found in the CD spectra of (S)-(-)-1-(2-pyridyl)ethylamine (II) and I. For (S)-(-)-1-(3-pyridyl)ethylamine (III), the corresponding CD maximum are neg. No CD maximum was found in the spectrum of (S)-(-)-1-(4-pyridyl)ethylamine (IV) from 240 to 300 nm. In each CD spectrum there is a maximum near 240 nm, neg. for I, II, and IV and pos. for III. No corresponding absorption maximum near 240 nm was detected in any of the uv spectra. A first-order perturbation treatment of the CD spectra indicates that the 2B2 state at 180 nm makes a significant contribution to the rotational strength of the longer wavelength transitions. The CD maximum at 260 nm is due to the 1B2 ← 1A1 (π → π*) transition; the 240 nm maximum to the elec. dipole forbidden 1A2 ← 1A1 (n → π*) transition; and the rotational strength of the allowed 1B1 ← 1A1 (n → π*) transition near 288 nm is too weak to give an observable CD maximum All CD maximum disappear when the pyridine N lone pair is protonated in strong acid. This study involved multiple reactions and reactants, such as (S)-1-(Pyridin-4-yl)ethanamine dihydrochloride (cas: 40154-80-1Reference of 40154-80-1).

(S)-1-(Pyridin-4-yl)ethanamine dihydrochloride (cas: 40154-80-1) belongs to pyridine derivatives. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. The lone pair is in an sp2 orbital, projecting outward from the ring in the same plane as the σ bonds. Reduced pyridines, namely tetrahydropyridines, dihydropyridines and piperidines, are found in numerous natural and synthetic compounds. The synthesis and reactivity of these compounds have often been driven by the fact many of these compounds have interesting and unique pharmacological properties. Reference of 40154-80-1

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem

Thiamine-dependent regulation of mammalian brain pyridoxal kinase in vitro and in vivo was written by Bunik, Victoria;Aleshin, Vasily;Nogues, Isabel;Kahne, Thilo;Parroni, Alessia;Contestabile, Roberto;Salvo, Martino Luigi;Graf, Anastasia;Tramonti, Angela. And the article was included in Journal of Neurochemistry in 2022.Category: pyridine-derivatives The following contents are mentioned in the article:

Vitamins B₁ (thiamine) and B₆ (pyridox (al/ine/amine)) are crucial for central nervous system (CNS) function and neurogenesis due to the coenzyme action of their phosphorylated derivatives in the brain metabolism of glucose and neurotransmitters. Here, the non-coenzyme action of thiamine on the major mammalian producers of pyridoxal-5′-phosphate (PLP), such as pyridoxal kinase (PdxK) and pyridoxine 5′-phosphate oxidase (PNPO), is characterized. Among the natural thiamine compounds, thiamine triphosphate (ThTP) is the best effector of recombinant human PdxK (hPdxK) in vitro, inhibiting hPdxK in the presence of Mg²⁺ but activating the Zn²⁺-dependent reaction. Inhibition of hPdxK by thiamine antagonists decreases from amprolium to pyrithiamine to oxythiamine, highlighting possible dysregulation of both the B₁– and B₆-dependent metabolism in the chem. models of thiamine deficiency. Compared with the canonical hPdxK, the D87H and V128I variants show a twofold increase in K_app of thiamine inhibition, and the V128I and H246Q variants show a fourfold and a twofold decreased K_app of thiamine diphosphate (ThDP), resp. Thiamine administration changes diurnal regulation of PdxK activity and phosphorylation at Ser213 and Ser285, expression of the PdxK-related circadian kinases/phosphatases in the rat brain, and electrocardiog. (ECG). In contrast to PdxK, PNPO is not affected by thiamine or its derivatives, either in vitro or in vivo. Dephosphorylation of the PdxK Ser285, potentially affecting mobility of the ATP-binding loop, inversely correlates with the enzyme activity. Dephosphorylation of the PdxK Ser213, which is far away from the active site, does not correlate with the activity. The correlations anal. suggests the PdxK Ser213 to be a target of kinase MAP2K1 and phosphatase Ppp1ca. Diurnal effects of thiamine administration on the metabolically linked ThDP- and PLP-dependent enzymes may support the brain homeostatic mechanisms and physiol. fitness. This study involved multiple reactions and reactants, such as (4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7Category: pyridine-derivatives).

(4-Formyl-5-hydroxy-6-methylpyridin-3-yl)methyl dihydrogen phosphate (cas: 54-47-7) belongs to pyridine derivatives. In contrast to benzene, Pyridine’s electron density is not evenly distributed over the ring, reflecting the negative inductive effect of the nitrogen atom. Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Category: pyridine-derivatives

Referemce:
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem