Month: November 2022

Chu, Te-Wei published the artcileHybrid polymeric hydrogels via peptide nucleic acid (PNA)/DNA complexation, Quality Control of 186046-81-1, the publication is Journal of Controlled Release (2015), 220(Part_B), 608-616, database is CAplus and MEDLINE.

This work presents a new concept in hybrid hydrogel design. Synthetic water-soluble N-(2-hydroxypropyl)methacrylamide (HPMA) polymers grafted with multiple peptide nucleic acids (PNAs) are crosslinked upon addition of the linker DNA. The self-assembly is mediated by the PNA-DNA complexation, which results in the formation of hydrophilic polymer networks. We show that the hydrogels can be produced through two different types of complexations. Type I hydrogel is formed via the PNA/DNA double-helix hybridization. Type II hydrogel utilizes a unique “P-form” oligonucleotide triple-helix that comprises two PNA sequences and one DNA. Microrheol. studies confirm the resp. gelation processes and disclose a higher critical gelation concentration for the type I gel when compared to the type II design. SEM reveals the interconnected microporous structure of both types of hydrogels. Type I double-helix hydrogel exhibits larger pore sizes than type II triple-helix gel. The latter apparently contains denser structure and displays greater elasticity as well. The designed hybrid hydrogels have potential as novel biomaterials for pharmaceutical and biomedical applications.

Journal of Controlled Release published new progress about 186046-81-1. 186046-81-1 belongs to pyrimidines, auxiliary class Pyrimidine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(4-(((benzhydryloxy)carbonyl)amino)-2-oxopyrimidin-1(2H)-yl)acetamido)acetic acid, and the molecular formula is C39H35N5O8, Quality Control of 186046-81-1.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Chu, Te-Wei published the artcileHybrid polymeric hydrogels via peptide nucleic acid (PNA)/DNA complexation, Related Products of pyrimidines, the publication is Journal of Controlled Release (2015), 220(Part_B), 608-616, database is CAplus and MEDLINE.

This work presents a new concept in hybrid hydrogel design. Synthetic water-soluble N-(2-hydroxypropyl)methacrylamide (HPMA) polymers grafted with multiple peptide nucleic acids (PNAs) are crosslinked upon addition of the linker DNA. The self-assembly is mediated by the PNA-DNA complexation, which results in the formation of hydrophilic polymer networks. We show that the hydrogels can be produced through two different types of complexations. Type I hydrogel is formed via the PNA/DNA double-helix hybridization. Type II hydrogel utilizes a unique “P-form” oligonucleotide triple-helix that comprises two PNA sequences and one DNA. Microrheol. studies confirm the resp. gelation processes and disclose a higher critical gelation concentration for the type I gel when compared to the type II design. SEM reveals the interconnected microporous structure of both types of hydrogels. Type I double-helix hydrogel exhibits larger pore sizes than type II triple-helix gel. The latter apparently contains denser structure and displays greater elasticity as well. The designed hybrid hydrogels have potential as novel biomaterials for pharmaceutical and biomedical applications.

Journal of Controlled Release published new progress about 169396-92-3. 169396-92-3 belongs to pyrimidines, auxiliary class Pyrimidine,Carboxylic acid,Amine,Amide,Others,PNA, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(5-methyl-2,4-dioxo-3,4-dihydropyrimidin-1(2H)-yl)acetamido)acetic acid, and the molecular formula is C26H26N4O7, Related Products of pyrimidines.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Gambacorta, Augusto published the artcileHSAB driven chemoselectivity in alkylation of uracil derivatives. A high yielding preparation of 3-alkylated and unsymmetrically 1,3-dialkylated uracils, Name: 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is Tetrahedron (1999), 55(43), 12615-12628, database is CAplus.

A qual. hardness scale (N¹<N³<O⁴) has been found for the conjugated bases of 2-methoxy-4(3H)-pyrimidinone and its 5- and 6-Me derivatives and applied to high yielding chemoselective N³ methylation, ethylation and benzylation reactions. Removal of the 2-methoxy group followed by a second alkylation affords unsym. 1,3-disubstituted uracils.

Tetrahedron published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Name: 3-Methylpyrimidine-2,4(1H,3H)-dione.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Shen, Gang published the artcilePhospholipid Conjugate for Intracellular Delivery of Peptide Nucleic Acids, SDS of cas: 186046-81-1, the publication is Bioconjugate Chemistry (2009), 20(9), 1729-1736, database is CAplus and MEDLINE.

Peptide nucleic acids (PNAs) have a number of attractive features that have made them an ideal choice for antisense and antigene-based tools, probes, and drugs, but their poor membrane permeability has limited their application as therapeutic or diagnostic agents. Herein, we report a general method for the synthesis of phospholipid-PNAs (LP-PNAs) and compare the effect of noncleavable lipids and bioreductively cleavable lipids (L and LSS) and phospholipid (LP) on the splice-correcting bioactivity of a PNA bearing the cell penetrating Arg9 group (PNA-R9). While the three constructs show similar and increasing bioactivity at 1-3 μM, the activity of LP-PNA-R9 continues to increase from 4-6 μM, while the activity of L-PNA-R9 remains constant and that of LSS-PNA-R9 decreases rapidly in parallel with their relative cytotoxicity. The activity of both LP-PNA-R9 and L-PNA-R9 dramatically increased in the presence of chloroquine, as expected for an endocytic entry mechanism. The constructs were also found to have CMC values of 1.0 and 4.5 μM, resp., in 150 mM NaCl, pH 7 water, suggesting that micelle formation may play a hitherto unrecognized role in modulating toxicity and/or facilitating endocytosis.

Bioconjugate Chemistry published new progress about 186046-81-1. 186046-81-1 belongs to pyrimidines, auxiliary class Pyrimidine,Carboxylic acid,Amine,Benzene,Amide,Others,PNA,, name is 2-(N-(2-((((9H-Fluoren-9-yl)methoxy)carbonyl)amino)ethyl)-2-(4-(((benzhydryloxy)carbonyl)amino)-2-oxopyrimidin-1(2H)-yl)acetamido)acetic acid, and the molecular formula is C6H4ClNO2, SDS of cas: 186046-81-1.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Mastryukov, Vladimir S. published the artcileThe effect of methylation on the structure of uracil, Safety of 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is Journal of Molecular Structure (1995), 173-86, database is CAplus.

Equilibrium geometries of uracil, 1-methyluracil and 3-methyluracil (in which the Me group is attached to nitrogen), 5-methyluracil (thymine) and 6-methyluracil (in which the Me group is attached to carbon), 1,3-dimethyluracil and 5,6-dimethyluracil have been determined by ab initio Hartree-Fock calculations with the split-valence 4-21G basis set. For the methylated derivatives, calculations are made for different conformations corresponding to different orientations of the Me groups. The conformational energy differences are small, indicating a very low barrier to internal rotation, except for 5- and 6-methyluracils in which there is a preference of 1-2kcalmol^-1 for the conformer with the Me C-H bond eclipsing the double bond of the ring. The structural differences between the methylated uracils and the parent mol. are analyzed. Angular deformations within the ring induced by substitution of a Me group for hydrogen follow, to a rough approximation, the trends established earlier for benzene derivatives on the basis of X-ray studies. Deviations occur due to the difference between nitrogen and carbon in the ring, with deformations being more pronounced for N- than for C-substituted uracils. The Me groups, in general, show a distinct tilt away from an adjacent carbonyl group, indicating a repulsive interaction. Mulliken population anal. shows the electroneg. Me group withdraws charge mainly from the atom to which it is attached and, to at least as great an extent, from the adjacent ring atoms. The results are compared with those obtained earlier by the semiempirical MINDO/3 method and also by different exptl. techniques including X-ray, neutron, and electron diffraction. These other studies have given much information on the structure of the compounds, but because of their nature they have not been able to analyze detailed structural variations induced by the Me group substitution.

Journal of Molecular Structure published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Safety of 3-Methylpyrimidine-2,4(1H,3H)-dione.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Gallup, Gordon A. published the artcileVibrational Feshbach resonances in dissociative electron attachment to uracil, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione, the publication is Physical Review A: Atomic, Molecular, and Optical Physics (2011), 83(1), 012706/1-012706/7, database is CAplus.

Low-energy dissociative electron attachment to uracil mols. in the gas phase is partly controlled by interaction between the lowest σ* resonance with a dipole-supported anion state. We calculate this contribution using a combination of the finite element discrete model with the resonance R-matrix theory. Deuterated uracil is investigated, also, and a strong isotope effect is found. The results agree qual. and semiquant. with exptl. data, but for a complete description of the process the interaction between a second N-H bond σ* resonance in the mol. and the second p* resonance should be included.

Physical Review A: Atomic, Molecular, and Optical Physics published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Recommanded Product: 3-Methylpyrimidine-2,4(1H,3H)-dione.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Rezk, Mamdouh R published the artcileChromatographic Methods for the Determination of Aminexil, Pyridoxine, and Niacinamide in a Novel Cosmetic Hair Preparation., SDS of cas: 74638-76-9, the publication is Journal of AOAC International (2020), 103(4), 1167-1172, database is MEDLINE.

BACKGROUND: Aminexil, a new compound patented by L’Oreal, has a stimulating effect on human keratin fibers. Pyridoxine HCl and niacinamide are added to boost the hair tonic effect of aminexil. OBJECTIVE: Two novel chromatographic methods were developed for the determination of aminexil (AX), niacinamide (NA) and pyridoxine HCl (PD) in the novel hair tonic preparation. METHODS: The developed methods were high-performance liquid chromatography (HPLC) and thin layer chromatography (TLC) with densitometric determination. Different experimental parameters were investigated and optimized to achieve complete baseline separation and well resolved peaks. The RP-HPLC separation was achieved using a Thermoscientific BDS hypersil C18 (250 × 4.6 mm, 5 µm) column using 0.005 M hexane sulfonic acid: methanol (80: 20, v/v) as a mobile phase. For the TLC method, the three analytes were partitioned between propanol: toluene: ammonia solution (40:60:2, v/v/v) and fluorescent silica plates. The two methods were validated in compliance with International Conference on Harmonization (ICH) guidelines. The obtained data were statistically analyzed to confirm the existing results. The developed methods were successfully applied for determination of the studied drugs in pure forms and in the cosmetic preparation. RESULTS: For the HPLC method, the RSDs of AX, NA and PD were 0.70, 0.88 and 1.17 respectively. For the TLC method, the RSDs of AX, NA and PD were 1.06, 1.37 and 0.73 respectively. CONCLUSIONS: The proposed chromatographic methods showed high sensitivity and selectivity for the three compounds under analysis in the laboratory prepared mixture and in the hair tonic preparation. HIGHLIGHTS: Aminexil, Pyridoxine, Niacinamide, HPLC. The present work offers two reproducible, accurate, validated, time and cost saving alternatives for the quantitative and qualitative determination of medicated hair preparation.

Journal of AOAC International published new progress about 74638-76-9. 74638-76-9 belongs to pyrimidines, auxiliary class Pyrimidine, name is 2,4-Diaminopyrimidine-3-oxide, and the molecular formula is C4H6N4O, SDS of cas: 74638-76-9.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Kratochvil, Martin published the artcileMethylated uracil dimers: potential energy and free energy surfaces, Related Products of pyrimidines, the publication is Physical Chemistry Chemical Physics (2000), 2(10), 2419-2424, database is CAplus.

Theor. anal. of the formation of 1-methyluracil, 3-methyluracil and 1,3-dimethyluracil dimers was performed. Stabilization energies of these dimers were evaluated with the Cornell et al. force field (J. Am. chem. Soc., 1995, 117, 5179). In total 16, 13 and 15 energy min. were studied for the 3 dimers. Thermodn. data were obtained with the rigid rotor-harmonic oscillator-ideal gas approximation Also, populations of various structures were determined by mol. dynamic simulations in the NVE microcanonical ensemble and numerical evaluation of the configuration integrals in the NVT canonical ensemble. The potential energy surfaces (PESs) and the free energy surfaces (FESs) of these dimers differ. The largest difference was found for the 1-methyluracil dimer where the global and 1st local min. on the PES and FES do not coincide.

Physical Chemistry Chemical Physics published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Related Products of pyrimidines.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Schultes, Sabine published the artcileCombining Quantum Mechanical Ligand Conformation Analysis and Protein Modeling to Elucidate GPCR-Ligand Binding Modes, HPLC of Formula: 56-05-3, the publication is ChemMedChem (2013), 8(1), 49-53, database is CAplus and MEDLINE.

2-Aminopyrimidine ligands with flexible and rigid side chains was synthesized to investigate the role of ligand conformation in H₄R ligand binding. The ligand binding conformations and orientations in the H₄R binding pocket was elucidated. The combined ligand- and protein-ligand modeling method can be used as a general approach to investigate the binding modes of flexible side chains of ligands with other protein targets.

ChemMedChem published new progress about 56-05-3. 56-05-3 belongs to pyrimidines, auxiliary class Pyrimidine,Chloride,Amine,API, name is 2-Amino-4,6-dichloropyrimidine, and the molecular formula is C25H29N9O3, HPLC of Formula: 56-05-3.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia

Notario, Rafael published the artcileThermochemistry of Uracils. Experimental and Computational Enthalpies of Formation of 5,6-Dimethyl-, 1,3,5-Trimethyl-, and 1,3,5,6-Tetramethyluracils, Application In Synthesis of 608-34-4, the publication is Journal of Physical Chemistry A (2013), 117(1), 244-251, database is CAplus and MEDLINE.

An exptl. and computational study of three methylated uracils, in particular, the 5,6-dimethyl-, 1,3,5-trimethyl-, and 1,3,5,6-tetra-Me derivatives are presented. The values of the standard (p⁰ = 0.1 MPa) molar enthalpies of formation in the gas phase at T = 298.15 K have been determined The energies of combustion were measured by static bomb combustion calorimetry, and from the results obtained, the standard molar enthalpies of formation in the crystalline state at T = 298.15 K were calculated The enthalpies of sublimation were determined using the transpiration method in a saturated N₂ stream. Values of -(376.2 ± 2.6), -(355.9 ± 3.0), and -(381.7 ± 2.8) kJ·mol^-1 for the gas-phase enthalpies of formation at T = 298.15 K of 5,6-dimethyluracil, 1,3,5-trimethyluracil, and 1,3,5,6-tetramethyluracil, resp., were obtained from the exptl. thermochem. study. An extended theor. study with the G3 and the G4 quantum-chem. methods has been carried out for all the possible methylated uracils. There is very good agreement between exptl. and calculated enthalpies of formation for the three derivatives studied. A Free-Wilson anal. on G4-calculated enthalpies of formation has been carried out, and the contribution of methylation in the different positions of the uracil ring has been estimated

Journal of Physical Chemistry A published new progress about 608-34-4. 608-34-4 belongs to pyrimidines, auxiliary class Pyrimidine,Amide, name is 3-Methylpyrimidine-2,4(1H,3H)-dione, and the molecular formula is C5H6N2O2, Application In Synthesis of 608-34-4.

Referemce:
https://pubchem.ncbi.nlm.nih.gov/compound/Pyrimidine,
Pyrimidine – Wikipedia