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1.
J Biopharm Stat ; : 1-16, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38860461

ABSTRACT

Physiologically based pharmacokinetic (PBPK) modeling serves as a valuable tool for determining the distribution and disposition of substances in the body of an organism. It involves a mathematical representation of the interrelationships among crucial physiological, biochemical, and physicochemical parameters. A lack of the values of pharmacokinetic parameters can be challenging in constructing a PBPK model. Herein, we propose an artificial intelligence framework to evaluate a key pharmacokinetic parameter, the intestinal effective permeability (Peff). The publicly available Peff dataset was utilized to develop regression machine learning models. The XGBoost model demonstrates the best test accuracy of R-squared (R2, coefficient of determination) of 0.68. The model is then applied to compute the Peff of asiaticoside and madecassoside, the parent compounds found in Centella asiatica. Subsequently, PBPK modeling was conducted to evaluate the biodistribution of the herbal substances following oral administration in a rat model. The simulation results were evaluated and validated, which agreed with the existing in vivo studies in rats. This in silico pipeline presents a potential approach for investigating the pharmacokinetic parameters and profiles of drugs or herbal substances, which can be used independently or integrated into other modeling systems.

2.
Chem Asian J ; 19(1): e202300808, 2024 Jan 02.
Article in English | MEDLINE | ID: mdl-37926693

ABSTRACT

Photodynamic therapy (PDT) is a photochemical-based treatment approach that involves using light to activate photosensitizers (PSs). Attractively, PDT is one of the alternative cancer treatments due to its noninvasive technique. By utilizing the heavy atom effect, this work modified a class of formazan dyes to improve intersystem crossing (ISC) to improve reactive oxygen species (ROS) generation for PDT treatment. Two methods were used to observe the ROS generation enhanced by ISC of the synthesized complexes including, (1) recording DPBF decomposition caused by the ROS, and (2) calculating the potential energy curves for photophysical mechanisms of BF2 -formazanate dyes using the DFT and nudged elastic band (NEB) methods. The photophysical properties of the dyes were studied using spectroscopic techniques and X-ray crystallography, as well as DFT calculations. The experimental and theoretical results and in vitro cellular assays confirmed the potential use of the newly synthesized iodinated BF2 -formazanate dyes in PDT.

3.
Biosensors (Basel) ; 12(11)2022 Oct 25.
Article in English | MEDLINE | ID: mdl-36354432

ABSTRACT

In this work, the two pyridylhydrazone-tethered BODIPY compounds (2 and 3) were synthesized. These compounds aimed to detect hypochlorous acid (HOCl) species via cyclic triazolopyridine formation. The open forms and the resulting cyclic forms of BODIPYs (2, 3, 4, and 5) were fully characterized by nuclear magnetic resonance, mass spectrometry, infrared spectroscopy, and single-crystal X-ray diffraction. These two probes can selectively detect HOCl through a fluorescence turn-on mechanism with the limit of detections of 0.21 µM and 0.77 µM for compounds 2 and 3, respectively. This fluorescence enhancement phenomenon could be the effect from C = N isomerization inhibition due to HOCl-triggered triazolopyridine formation. In cell imaging experiments, these compounds showed excellent biocompatibility toward RAW 264.7 murine live macrophage cells and greatly visualized endogenous HOCl in living cells stimulated with lipopolysaccharide.


Subject(s)
Fluorescent Dyes , Hypochlorous Acid , Mice , Animals , Hypochlorous Acid/analysis , Hypochlorous Acid/chemistry , Fluorescent Dyes/chemistry , Boron Compounds/chemistry , Fluorescence
4.
Molecules ; 27(19)2022 Sep 22.
Article in English | MEDLINE | ID: mdl-36234769

ABSTRACT

Autophagy is the multistep mechanism for the elimination of damaged organelles and misfolded proteins. This mechanism is preceded and may induce other program cell deaths such as apoptosis. This study unraveled the potential pharmacological effect of 24MD in inducing the autophagy of lung cancer cells. Results showed that 24MD was concomitant with autophagy induction, indicating by autophagosome staining and the induction of ATG5, ATG7 and ubiquitinated protein, p62 expression after 12-h treatment. LC3-I was strongly conversed to LC3-II, and p62 was downregulated after 24-h treatment. The apoptosis-inducing activity was found after 48-h treatment as indicated by annexin V-FITC/propidium iodide staining and the activation of caspase-3. From a mechanistic perspective, 24-h treatment of 24MD at 60 µM substantially downregulated p-mTOR. Meanwhile, p-PI3K and p-Akt were also suppressed by 24MD at concentrations of 80 and 100 µM, respectively. We further confirmed m-TOR-mediated autophagic activity by comparing the effect of 24MD with rapamycin, a potent standard mTOR1 inhibitor through Western blot and immunofluorescence assays. Although 24MD could not suppress p-mTOR as much as rapamycin, the combination of rapamycin and 24MD could increase the mTOR suppressive activity and LC3 activation. Changing the substituent groups (R groups) from dimethylphenol to ethylphenol in EMD or changing methylazanedyl to cyclohexylazanedyl in 24CD could only induce apoptosis activity but not autophagic inducing activity. We identified 24MD as a novel compound targeting autophagic cell death by affecting mTOR-mediated autophagy.


Subject(s)
Autophagic Cell Death , Lung Neoplasms , Apoptosis , Autophagy , Caspase 3/metabolism , Cell Line, Tumor , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Propidium/pharmacology , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction , Sirolimus/pharmacology , TOR Serine-Threonine Kinases/metabolism , Ubiquitinated Proteins/pharmacology , Ubiquitinated Proteins/therapeutic use , Xylenes
5.
Cancer Genomics Proteomics ; 19(5): 624-635, 2022.
Article in English | MEDLINE | ID: mdl-35985690

ABSTRACT

BACKGROUND/AIM: Metastasis negatively affects the survival of lung cancer patients, however, relatively few compounds have potential in metastasis suppression. This study investigated the molecular targets of N,N-bis (5-ethyl-2-hydroxybenzyl) methylamine (EMD) for metastatic inhibition. MATERIALS AND METHODS: Proteins were analyzed by proteomic and bioinformatic analyses. Protein-protein interaction (PPI) networks were created with the Search Tool for the Retrieval of Interacting Genes. The Kyoto Encyclopedia of Genes and Genomes database and hub genes were used to determine dominant pathways. Immunofluorescence and western blot analyses validated the proteomic results and investigated signaling pathways in NCI-H23 lung cancer cells. RESULTS: A total of 1,751 proteins were common to the control, EMD and N,N-bis(5-methoxy-2-hydroxybenzyl) methylamine (MeMD) groups; 1,980 different proteins were categorized using metastatic capacity category and analyzed for unique proteins affected by EMD. Fifteen proteins were associated with cell adhesion and six with cell migration. Nectin cell adhesion molecule 2 (NECTIN2) was expressed in the control and MeMD-treated groups but not the EMD-treated group, suggesting NECTIN2 as an EMD target. PPI network showed association of NECTIN2 with proteins regulating cancer metastasis. Kyoto Encyclopedia of Genes and Genomes pathways revealed that NECTIN2 is an upstream target of cytoskeletal regulation via SRC signaling. Western blot and immunofluorescence analyses confirmed that EMD suppressed NECTIN2, and its downstream targets, including p-SRC (Y146 and Y527) and the epithelial-to-mesenchymal transition markers tight junction protein 1, vimentin, ß-catenin, snail family transcriptional repressor 1 (SNAI1), and SNAI2, while increasing E-cadherin. CONCLUSION: EMD suppressed NECTIN2-induced activation of EMT signaling. These data support the development of EMD to prevent metastasis of lung cancer.


Subject(s)
Lung Neoplasms , Nectins , Humans , Cell Line, Tumor , Cell Movement , Epithelial-Mesenchymal Transition , Lung Neoplasms/drug therapy , Lung Neoplasms/genetics , Methylamines/pharmacology , Nectins/drug effects , Nectins/metabolism , Proteomics
6.
Chem Commun (Camb) ; 58(68): 9468-9471, 2022 Aug 23.
Article in English | MEDLINE | ID: mdl-35894790

ABSTRACT

Heptagon-embedded polycyclic aromatic dicarboximides were developed as new push-pull fluorescent dyes through palladium-catalysed [4+3] annulation followed by nucleophilic substitution. The introduction of a seven-membered ring in these push-pull systems can efficiently modulate the optical properties leading to an enhancement of the fluorescence quantum yields up to 0.93 with color tunable emission covering the visible-NIR spectrum.


Subject(s)
Fluorescent Dyes , Palladium , Catalysis , Spectrometry, Fluorescence
7.
Sci Rep ; 12(1): 11058, 2022 Jun 30.
Article in English | MEDLINE | ID: mdl-35773302

ABSTRACT

Rapid advancements in perovskite materials have led to potential applications in various optoelectronic devices, such as solar cells, light-emitting diodes, and photodetectors. Due to good photoelectric properties, perovskite enables low-cost and comparable performance in terms of responsivity, detectivity, and speed to those of the silicon counterpart. In this work, we utilized triple cation perovskite, well known for its high performance, stability, and wide absorption range, which is crucial for broadband photodetector applications. To achieve improved detectivity and faster response time, graded multilayer perovskite absorbers were our focus. Sequential spray deposition, which allows stacked perovskite architecture without disturbing lower perovskite layers, was used to generate single, double, and triple-layer perovskite photodetectors with proper energy band alignment. In this work, we achieved a record on self-powered perovskite photodetector fabricated from a scalable spray process in terms of EQE and responsivity of 65.30% and 0.30 A W-1. The multilayer devices showed faster response speed than those of single-layer perovskite photodetectors with the champion device reaching 70 µs and 88 µs for rising and falling times. The graded band structure and the internal electric field generated from perovskite heterojunction also increase specific detectivity about one magnitude higher in comparison to the single-layer with the champion device achieving 6.82 × 1012 cmHz1/2 W-1.

8.
Inorg Chem ; 61(20): 7945-7963, 2022 May 23.
Article in English | MEDLINE | ID: mdl-35537466

ABSTRACT

Two series of titanium complexes, including salicylbenzoxazole titanium complexes (1-4) and salicylbenzothiazole titanium complexes (5-8), were successfully synthesized and characterized by NMR spectroscopy, elemental analysis, and X-ray diffraction crystallography (for 2 and 5). The 1H NMR spectra of complexes 7 and 8 reveal fluxional behavior in solution at room temperature, and the activation parameters were determined by lineshape analysis of variable-temperature (VT) NMR spectra in toluene-d8: for 7, ΔH⧧ = 73.0 ± 1.8 kJ mol-1, ΔS⧧ = 22.1 ± 5.5 J mol-1 K-1; for 8, ΔH⧧ = 73.7 ± 1.2 kJ mol-1, ΔS⧧ = 20.3 ± 3.8 J mol-1 K-1. The positive values of ΔS⧧ suggested that the isomerization occurred via a dissociative mechanism. All complexes were active initiators for the ring-opening polymerization of ε-caprolactone (ε-CL) and three substituted ε-CLs: γ-methyl-ε-caprolactone (γMeCL), γ-ethyl-ε-caprolactone (γEtCL), and γ-phenyl-ε-caprolactone (γPhCL). Of all complexes, complex 5 was found to be the most active initiator in this study. The copolymerizations between ε-CL and three substituted ε-CLs produced completely random copolymers. The polymerization was proposed to proceed via a dissociative coordination-insertion mechanism. The catalytic activity of the salicylbenzoxazole titanium complex was lower than that of its closely related salicylbenzothiazole titanium congener. Additionally, DFT calculations unveiled that the ligand decoordination step and the less steric congestion at the titanium center in the salicylbenzothiazole titanium complexes were the key factors in enhancing the catalytic rate.


Subject(s)
Caproates , Titanium , Caproates/chemistry , Lactones , Ligands , Polymerization , Titanium/chemistry
9.
Molecules ; 26(17)2021 Sep 06.
Article in English | MEDLINE | ID: mdl-34500842

ABSTRACT

Among lanthanide-based compounds, cerium compounds exhibit a significant role in a variety of research fields due to their distinct tetravalency, high economic feasibility, and high stability of Ce(IV) complexes. Herein, a systematic investigation of crystallographic information, chemical properties, and mechanistic formation of the novel Ce(IV) complex synthesized from cerium(III) nitrate hexahydrate and 2,2'-(methylazanediyl)bis(methylene)bis(4-methylphenol) (MMD) ligand has been explored. According to the analysis of the crystallographic information, the obtained complex crystal consists of the Ce(IV) center coordinated with two nitrate ligands and two bidentate coordinated (N-protonated and O,O-deprotonated) MMD ligands. The fingerprint plots and the Hirshfeld surface analyses suggest that the C-H⋯O and C-H⋯π interactions significantly contribute to the crystal packing. The C-H⋯O and C-H⋯π contacts link the molecules into infinite molecular chains propagating along the [100] and [010] directions. Synchrotron powder X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) techniques have been employed to gain an understanding of the oxidative complexation of Ce(IV)-MMD complex in detail. This finding would provide the possibility to systematically control the synthetic parameters and wisely design the precursor components in order to achieve the desired properties of novel materials for specific applications.

10.
Dalton Trans ; 50(31): 10964-10981, 2021 Aug 21.
Article in English | MEDLINE | ID: mdl-34318841

ABSTRACT

A series of six-coordinate titanium complexes 1-6 supported by pyrrolylaldiminate ligands were prepared via the reaction of 2 equivalents of ligands and Ti(OiPr)4 in toluene at 70 °C. The X-ray structure of 2 revealed that the two ligands were κ2-coordinated to the titanium center with the two pyrrole nitrogen atoms in trans positions and the two imine nitrogen atoms in cis positions. All complexes were active initiators for the ring-opening polymerization (ROP) of rac-lactide (rac-LA), ε-caprolactone (ε-CL), and three substituted ε-caprolactones (γ-methyl-ε-caprolactone (γMeCL), γ-ethyl-ε-caprolactone (γEtCL), and γ-phenyl-ε-caprolactone (γPhCL)). Polymerizations of all monomers were well controlled, affording predetermined molar masses and narrow dispersity values. Complex 5 exhibited the highest polymerization activities with rac-LA and ε-CL and its performance was comparable to other highly active six-coordinate titanium complexes reported thus far. Kinetic results revealed a first-order dependency on the monomer concentration, and the rate of polymerization was greatly influenced by the substituent on the imine nitrogen. End-group analysis of the isolated PLA and PCL suggested a coordination-insertion mechanism.

11.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 8): 1239-1244, 2020 Aug 01.
Article in English | MEDLINE | ID: mdl-32844006

ABSTRACT

In the title unsymmetrical tertiary amine, C24H33NO2, which arose from the ring-opening reaction of a di-hydro-benzoxazine, two 2,4-di-methyl-phenol moieties are linked by a 6,6'-(cyclo-hexyl-aza-nedi-yl)-bis-(methyl-ene) bridge: the dihedral angle between the dimethyl-phenol rings is 72.45 (7)°. The cyclo-hexyl ring adopts a chair conformation with the exocyclic C-N bond in an equatorial orientation. One of the phenol OH groups forms an intra-molecular O-H⋯N hydrogen bond, generating an S(6) ring, and a short intra-molecular C-H⋯O contact is also present. In the crystal, O-H⋯O hydrogen bonds link the mol-ecules into C(10) chains propagating along the [100] direction. The Hirshfeld surface analysis of the title compound confirms the presence of these intra- and inter-molecular inter-actions. The corresponding fingerprint plots indicate that the most significant contacts in the crystal packing are H⋯H (76.4%), H⋯C/C⋯H (16.3%), and H⋯O/O⋯H (7.2%).

12.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 7): 1027-1032, 2020 Jul 01.
Article in English | MEDLINE | ID: mdl-32695446

ABSTRACT

The mol-ecular structure of the title compound {systematic name: 3',6'-bis(di-ethyl-amino)-2-[(2-hy-droxy-benzyl-idene)amino]-spiro-[isoindoline-1,9'-xan-then]-3-one}, C35H36N4O3 or RbSa, can be seen as being composed of two parts sharing a central quaternary carbon atom. Both the xanthene and iso-indole moieties are nearly planar: 14 atoms in the former moiety show an r.m.s. deviation of 0.0411 Šand eleven atoms in the latter moiety show an r.m.s. deviation of 0.0545 Å. These two planes are almost perpendicular to each other, the angle between the mean planes being 87.71 (2)°. The title compound appears to be in its enol form. The corresponding H atom was located and freely refined at a distance of 1.02 (3) Šfrom the O atom and 1.72 (2) Šfrom the N atom. The strong intra-molecular hydrogen bond O-H⋯N bridging the hydroxyl group and its neighboring nitro-gen atom forms an S(6) graph-set motif. Apart from the intra-molecular O-H⋯N hydrogen bond, C-H⋯O inter-actions are observed between two neighbouring RbSa mol-ecules related by an inversion center. The C-O donor-acceptor distance is 3.474 (2) Å. Moreover, C-H⋯π inter-actions are observed between the C-H bond of one of the ethyl groups and the centroid of the benzene ring of the iso-indole moiety. The C⋯centroid distance is 3.8191 (15) Å. No π-π inter-actions are observed in the crystal structure as the shortest distance between ring centroids is more than 4 Å. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H⋯H, C⋯H/H⋯C, O⋯H/H⋯O and N⋯H/H⋯N inter-actions. DFT calculations at the CAM-B3LYP/6-31 G(d) level were carried out to gain a better understanding of the relative energies and the tautomerization process between two possible conformers (keto and enol), as well as the transition state of the title compound.

13.
Mol Pharmacol ; 98(2): 130-142, 2020 08.
Article in English | MEDLINE | ID: mdl-32487733

ABSTRACT

Aberrant cellular Myc (c-Myc) is a common feature in the majority of human cancers and has been linked to oncogenic malignancies. Here, we developed a novel c-Myc-targeting compound, N, N-bis (5-ethyl-2-hydroxybenzyl) methylamine (EMD), and present evidence demonstrating its effectiveness in targeting c-Myc for degradation in human lung carcinoma. EMD exhibited strong cytotoxicity toward various human lung cancer cell lines, as well as chemotherapeutic-resistant patient-derived lung cancer cells, through apoptosis induction in comparison with chemotherapeutic drugs. The IC50 of EMD against lung cancer cells was approximately 60 µM. Mechanistically, EMD eliminated c-Myc in the cells and initiated caspase-dependent apoptosis cascade. Cycloheximide chase assay revealed that EMD tended to shorten the half-life of c-Myc by approximately half. The cotreatment of EMD with the proteasome inhibitor MG132 reversed its c-Myc-targeting effect, suggesting the involvement of ubiquitin-mediated proteasomal degradation in the process. We further verified that EMD strongly induced the ubiquitination of c-Myc and promoted protein degradation. c-Myc inhibition and apoptosis induction were additionally shown in hematologic malignant K562 cells, indicating the generality of the observed EMD effects. Altogether, we identified EMD as a novel potent compound targeting oncogenic c-Myc that may offer new opportunities for lung cancer treatment. SIGNIFICANCE STATEMENT: The deregulation of c-Myc is frequently associated with cancer progression. This study examined the effect of a new compound, N, N-bis (5-ethyl-2-hydroxybenzyl) methylamine (EMD), in targeting c-Myc in several lung cancer cell lines and drug-resistant primary lung cancer cells. EMD induced dramatic c-Myc degradation through a ubiquitin-proteasomal mechanism. The promising anticancer and c-Myc-targeted activities of EMD support its use in potential new approaches to treat c-Myc-driven cancer.


Subject(s)
Antineoplastic Agents/chemical synthesis , Lung Neoplasms/metabolism , Methylamines/chemical synthesis , Proto-Oncogene Proteins c-myc/chemistry , Proto-Oncogene Proteins c-myc/metabolism , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Cell Survival , Drug Resistance, Neoplasm/drug effects , Humans , K562 Cells , Lung Neoplasms/drug therapy , Methylamines/chemistry , Methylamines/pharmacology , Molecular Structure , Proteasome Endopeptidase Complex/metabolism , Proteolysis , Proto-Oncogene Proteins c-myc/drug effects , Ubiquitin/metabolism
14.
Anticancer Res ; 40(5): 2583-2589, 2020 May.
Article in English | MEDLINE | ID: mdl-32366403

ABSTRACT

BACKGROUND/AIM: Certain integrins including integrin ß3 facilitate movement and survival of metastatic cancer cells. We examined whether benzoxazine dimer analogue N,N-bis(5-ethyl-2-hydroxybenzyl) methylamine (HM) has anti-metastatic effects. MATERIALS AND METHODS: Cell viability was examined by the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) assay. Wound healing and phalloidin-rhodamine assays were performed to evaluate the migration and filopodia formation, respectively. Anoikis resistance was studied by anchorage-independent growth assay. The expression of proteins regulating migration were examined by western blot. RESULTS: HM treatment significantly inhibited growth and survival of detached lung cancer cells as indicated by the reduced colony number and size of anchorage-independent growth analysis. HM inhibited cell migration and suppressed filopodia formation. Protein analysis indicated that the compound dramatically decreased integrin ß3 and its related downstream proteins including active focal adhesion kinase (FAK) and active protein kinase B (AKT); however, integrin ß1 and α5 were found to be unaltered. CONCLUSION: HM shows a potential in targeting integrin ß3 and could be a good candidate for further developed as an anti-metastatic therapy.


Subject(s)
Anoikis/drug effects , Antineoplastic Agents/pharmacology , Benzoxazines/pharmacology , Cell Movement/drug effects , Integrin beta3/metabolism , Antineoplastic Agents/chemistry , Benzoxazines/chemistry , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Humans , Lung Neoplasms , Models, Biological , Wound Healing/drug effects
15.
Acta Crystallogr E Crystallogr Commun ; 76(Pt 4): 594-598, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32280511

ABSTRACT

In the title compound, C9H10ClNOS, the amide functional group -C(=O)NH- adopts a trans conformation with the four atoms nearly coplanar. This conformation promotes the formation of a C(4) hydrogen-bonded chain propagating along the [010] direction. The central part of the mol-ecule, including the six-membered ring, the S and N atoms, is fairly planar (r.m.s. deviation of 0.014). The terminal methyl group and the C(=O)CH2 group are slightly deviating out-of-plane while the terminal Cl atom is almost in-plane. Hirshfeld surface analysis of the title compound suggests that the most significant contacts in the crystal are H⋯H, H⋯Cl/Cl⋯H, H⋯C/C⋯H, H⋯O/O⋯H and H⋯S/S⋯H. π-π inter-actions between inversion-related mol-ecules also contribute to the crystal packing. DFT calculations have been performed to optimize the structure of the title compound using the CAM-B3LYP functional and the 6-311 G(d,p) basis set. The theoretical absorption spectrum of the title compound was calculated using the TD-DFT method. The analysis of frontier orbitals revealed that the π-π* electronic transition was the major contributor to the absorption peak in the electronic spectrum.

16.
Dalton Trans ; 46(33): 11013-11030, 2017 Aug 22.
Article in English | MEDLINE | ID: mdl-28782768

ABSTRACT

Two series of aluminium complexes bearing salicylbenzothiazole ligands, namely four-coordinate aluminium complexes (1a-7a) and five-coordinate aluminium complexes (1b-7b), were synthesized and characterized by NMR spectroscopy, elemental analysis and X-ray diffraction crystallography (for 5a and 1b). Their application in the ring-opening polymerisation of rac-lactide and ε-caprolactone was studied with the aim of drawing comparisons to closely related aluminium salicylbenzoxazole complexes investigated previously. In the presence of benzyl alcohol, all complexes were active initiators and polymerisations were all well controlled and living. Kinetic studies revealed first-order kinetics in the monomer. In contrast, the catalytic activity of aluminium salicylbenzothiazole complexes was lower than that of aluminium salicylbenzoxazole counterparts. Detailed DFT calculations were performed and indicated that the observed lower catalytic activity of aluminium salicylbenzothiazole complexes agreed well with the observed higher Gibbs free energy at the ring-opening transition state.


Subject(s)
Aluminum/chemistry , Benzothiazoles/chemistry , Caproates/chemistry , Dioxanes/chemistry , Lactones/chemistry , Organometallic Compounds/chemistry , Polymerization , Ligands , Quantum Theory
17.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): o3050, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-23125812

ABSTRACT

The title compound, C(24)H(33)NO(2), exhibits an intra-molecular hydrogen bond between a phenol -OH group and the N atom. In the crystal, mol-ecules are connected by pairs of O-H⋯O hydrogen bonds.

18.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1826, 2012 Jun 01.
Article in English | MEDLINE | ID: mdl-22719598

ABSTRACT

In the title compound, C(19)H(25)NO(2), the dihedral angle between the benzene rings is 53.15 (8)°. One of the -OH groups forms an intra-molecular O-H⋯N link, generating an S(6) ring. The other -OH group forms an inter-molecular O-H⋯N hydrogen bond in the crystal, generating centrosymmetric R(2) (2)(20) loops.

19.
Molecules ; 17(1): 511-26, 2012 Jan 05.
Article in English | MEDLINE | ID: mdl-22222910

ABSTRACT

A series of benzoxazine monomer supramolecules with different substituted groups on their benzene ring was prepared with a Mannich reaction and characterized by FTIR, 1H-NMR and MS. The obtained products were 3,4-dihydro-3-(2'-hydroxyethylene)-6-methyl-2H-benzoxazine (BM1), 3,4-dihydro-3-(2'-hydroxyethylene)-6-ethyl-2H-benz-oxazine (BM2), and 3,4-dihydro-3-(2'-hydroxyethylene)-6-methoxy-2H-benzoxazine (BM3). The efficiency of alkali metal ion extraction from the products was determined with Pedersen's technique, while the complexation of the Ce(III) ion was confirmed by the Job's and the mole ratio methods. The evidence of complex formation between benzoxazine monomers and Ce(III) ions was obtained with FTIR and a computational simulation. Single phase ceria (CeO2) as observed with XRD was successfully prepared by calcinating the Ce(III)-benzoxazine monomer complexes at 600 °C for 2 h. In addition, the geometry of the ceria nanoparticles confirmed by TEM is spherical, with an average diameter of 10-20 nm.


Subject(s)
Benzoxazines/chemical synthesis , Cerium/chemistry , Coordination Complexes/chemical synthesis , Metals, Alkali/chemistry , Benzoxazines/chemistry , Cerium/isolation & purification , Computer Simulation , Coordination Complexes/chemistry , Metals, Alkali/isolation & purification , Models, Chemical , Nanoparticles , Particle Size , Powder Diffraction , Spectroscopy, Fourier Transform Infrared , Thermodynamics , X-Ray Diffraction
20.
Int J Mol Sci ; 12(7): 4365-77, 2011.
Article in English | MEDLINE | ID: mdl-21845083

ABSTRACT

N,N-bis(2-hydroxybenzyl)alkylamines, benzoxazine dimers, are the major product produced from benzoxazine monomers on mono-functional phenol by the one step ring opening reaction. Due to the metal responsive property of benzoxazine dimers, in this present work, N,N-bis(5-methyl-2-hydroxybenzyl)methylamine (MMD), N,N-bis (5-ethyl-2-hydroxybenzyl)methylamine (EMD), and N,N-bis(5-methoxy-2-hydroxybenzyl) methyl amine (MeMD), are considered as novel ligands for rare earth metal ion, such as cerium(III) ion. The complex formed when the clear and colorless solutions of cerium nitrate and benzoxazine dimers were mixed, results in a brown colored solution. The metal-ligand ratios determined by the molar ratio and the Job's methods were found to be in a ratio of 1:6. To clarify the evidence of the complex formation mechanism, the interactions among protons in benzoxazine dimers both prior to and after the formation of complexes were determined by means of (1)H-NMR, 2D-NMR and a computational simulation. The single phase ceria (CeO(2)) was successfully prepared by thermal decomposition of the Ce(III)-benzoxazine dimer complexes at 600 °C for 2 h, was then characterized using XRD. In addition, the ceria powder investigated by TEM is spherical with an average diameter of 20 nm.


Subject(s)
Benzoxazines/chemistry , Cerium/chemistry , Coordination Complexes/chemistry , Nanostructures/chemistry , Dimerization , Ligands , Molecular Conformation , Particle Size , Temperature , X-Ray Diffraction
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