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1.
Chem Commun (Camb) ; 60(36): 4810-4813, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38602391

ABSTRACT

The non-canonical amino acid adamantylglycine (Ada) is introduced into peptides to allow high-affinity binding to cucurbit[7]uril (CB7). Introduction of Ada into a cell-penetrating peptide (CPP) sequence had minimal influence on the membrane transport, yet enabled up- and down-regulation of the membrane transport activity.


Subject(s)
Cell-Penetrating Peptides , Glycine , Heterocyclic Compounds, 2-Ring , Imidazolidines , Macrocyclic Compounds , Glycine/chemistry , Glycine/analogs & derivatives , Glycine/metabolism , Cell-Penetrating Peptides/chemistry , Cell-Penetrating Peptides/metabolism , Imidazoles/chemistry , Humans , Bridged-Ring Compounds/chemistry , Bridged-Ring Compounds/metabolism , Adamantane/chemistry , Adamantane/analogs & derivatives , Cell Membrane/metabolism , Cell Membrane/chemistry , Biological Transport
2.
Phys Chem Chem Phys ; 26(17): 13420-13431, 2024 May 01.
Article in English | MEDLINE | ID: mdl-38647171

ABSTRACT

Autoimmune inflammatory diseases, such as rheumatoid arthritis (RA) and ulcerative colitis, are associated with an uncontrolled production of cytokines leading to the pronounced inflammatory response of these disorders. Their therapy is currently focused on the inhibition of cytokine receptors, such as the Janus kinase (JAK) protein family. Tofacitinib and peficitinib are JAK inhibitors that have been recently approved to treat rheumatoid arthritis. In this study, an in-depth analysis was carried out through quantum biochemistry to understand the interactions involved in the complexes formed by JAK1 and tofacitinib or peficitinib. Computational analyses provided new insights into the binding mechanisms between tofacitinib or peficitinib and JAK1. The essential amino acid residues that support the complex are also identified and reported. Additionally, we report new interactions, such as van der Waals; hydrogen bonds; and alkyl, pi-alkyl, and pi-sulfur forces, that stabilize the complexes. The computational results revealed that peficitinib presents a similar affinity to JAK1 compared to tofacitinib based on their interaction energies.


Subject(s)
Adamantane/analogs & derivatives , Janus Kinase 1 , Niacinamide , Niacinamide/analogs & derivatives , Piperidines , Pyrimidines , Pyrimidines/chemistry , Pyrimidines/pharmacology , Piperidines/chemistry , Piperidines/pharmacology , Piperidines/therapeutic use , Niacinamide/chemistry , Janus Kinase 1/antagonists & inhibitors , Janus Kinase 1/metabolism , Janus Kinase 1/chemistry , Humans , Quantum Theory , Autoimmune Diseases/drug therapy , Protein Kinase Inhibitors/chemistry , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Hydrogen Bonding , Janus Kinase Inhibitors/chemistry , Janus Kinase Inhibitors/therapeutic use , Janus Kinase Inhibitors/pharmacology , Adamantane/chemistry , Pyrroles/chemistry , Pyrroles/pharmacology , Molecular Docking Simulation
3.
Bioorg Chem ; 144: 107145, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38278050

ABSTRACT

Hyperadamans A-G (1-7), seven new adamantane type polycyclic polyprenylated acylphloroglucinols (PPAPs), were isolated from Hypericum wilsonii N. Robson. Structurally, 1-4 were the first adamantanes bearing an unusual 2,7-dioxabicyclo-[2.2.1]-heptane fragment, and compound 5 was the first adamantane with a rare 1,6-dioxaspiro[4.4]nonane section. Importantly, 1-7 exhibited significant immunosuppressive activity on Con A-induced T-lymphocyte proliferation in vitro, with IC50 values ranging from 3.97 ± 0.10 to 18.12 ± 1.07 µM. Pretreatment with 1 in Con A-challenged autoimmune hepatitis mice could dramatically ameliorate the levels of hepatic injury indexes (ALT and AST) and reduce the product of proinflammatory cytokines (COX-2, IL-6, IL-1ß, IL-18, IL-23A and TNF-α). Furthermore, the protective effect of 1 on the Con A-induced liver injury was corroborated by the histological analysis and the immunohistochemistry.


Subject(s)
Adamantane , Hepatitis, Autoimmune , Mice , Animals , Concanavalin A , Hepatitis, Autoimmune/drug therapy , Hepatitis, Autoimmune/prevention & control , Adamantane/pharmacology , Adamantane/chemistry , Cytokines , Tumor Necrosis Factor-alpha , Molecular Structure
4.
Chemistry ; 29(65): e202302782, 2023 Nov 21.
Article in English | MEDLINE | ID: mdl-37749057

ABSTRACT

The fluorescence of functional dyes was generally quenched in aqueous solution, which hindered their application in water-bearing detections. In this work, a novel strategy based on host-guest interaction was provided for the purpose of fluorescence enhancement in aqueous solution and cell imaging. Three adamantane-modified fluorescent dyes (Coum-Ad, NP-Ad, NR-Ad) with coumarin, 1,8-naphthalimide and Nile Red as fluorophores were initially designed and prepared. The ((adamantan-1-yl)methyl)amino group, as the auxochrome of those dyes, complexed with methylated ß-cyclodextrin (M-ß-CD) via supramolecular interaction, and then fluorescent supramolecular nanoparticles (FSNPs) were formed by self-assembly in water. The inclusion equilibrium constant (K) could be as high as 3.94×104  M-1 . With the addition of M-ß-CD, fluorescence quantum yields of these dyes were separately improved to 69.8 %, 32.9 % and 41.3 %. Inspired by the above satisfactory results, six adamantane-modified probes organelle-NPAds with organelle-targeting capability were further obtained. As the formation of hydrogen bonds between organelle-NPAd2 and M-ß-CD verified by theoretical calculation, K of organelle-NPAd2 (5.13×104  M-1 ~4.53×105  M-1 ) with M-ß-CD was higher than that of organelle-NPAd1 (1.15×104  M-1 ~3.66×104  M-1 ) and their fluorescence quantum yields increased to 32.8 %~83.6 % in aqueous solution. In addition, fluorescence enhancement was realized in cell imaging with the addition of M-ß-CD.


Subject(s)
Adamantane , beta-Cyclodextrins , Adamantane/chemistry , beta-Cyclodextrins/chemistry , Fluorescent Dyes/chemistry , Water/chemistry
5.
J Nucl Med ; 64(8): 1203-1209, 2023 08.
Article in English | MEDLINE | ID: mdl-37024305

ABSTRACT

The goal of reducing the total-body radiation dose of macromolecule-based nuclear medicine with a 2-step pretargeting strategy has been achieved with several pretargeting methodologies in preclinical and clinical settings. However, the lack of modularity, biocompatibility, and in vivo stability in existing pretargeting agents obstructs their respective platforms' wide clinical use. We hypothesized that host-guest chemistry would provide an optimal pretargeting methodology. A cucurbit[7]uril host and an adamantane guest molecule form a high-affinity host-guest complex (association constant, ∼1014 M-1), and in this work, we explored the use of this noncovalent interaction as the basis for antibody-based pretargeted PET. Along with the straightforward modularity of these agents, cucurbit[7]uril and adamantane are recognized to have high in vivo stability and suitability for human use, which is why we proposed this methodology as the ideal approach for pretargeted nuclear medicine. Methods: Three 64Cu-labeled adamantane guest radioligands were developed, and their in vitro stability, lipophilicity, and in vivo blood half-lives were compared. The adamantane radioligands were analyzed for pretargeting using a cucurbit[7]uril-modified carcinoembryonic antigen-targeting full-length antibody, hT84.66-M5A, as the macromolecule pretargeting agent with 2 different dosing schedules. These molecules were evaluated for pretargeting in human pancreatic cancer BxPC3 and MIAPaCa-2 mouse xenografts using PET and in vivo biodistribution studies. The dosimetry of the cucurbit[7]uril-adamantane (CB7-Adma) pretargeting approach in men was calculated and compared with that of the directly 89Zr-labeled hT84.66-M5A. Results: The adamantane radioligands possessed high in vitro stability up to 24 h (>90%). Pretargeted PET with CB7-Adma methodology resulted in specific tumor uptake (P < 0.05) with low background signal. The in vivo formed CB7-Adma complex was demonstrated to be stable, with high tumor uptake up to 24 h after radioligand injection (12.0 ± 0.9 percentage injected dose/g). The total-body radiation dose of the pretargeting strategy was only 3.3% that of the directly 89Zr-labeled hT84.66-M5A. Conclusion: The CB7-Adma strategy is highly suitable for pretargeted PET. The exceptional stability of the pretargeting agents and the specific and high tumor uptake of the pretargeted adamantane radioligands provide great potential for the platform.


Subject(s)
Adamantane , Male , Humans , Animals , Mice , Adamantane/chemistry , Tissue Distribution , Heterografts , Antibodies/metabolism
6.
Macromol Rapid Commun ; 44(16): e2200869, 2023 Aug.
Article in English | MEDLINE | ID: mdl-36702804

ABSTRACT

The integration of microscopic hydrogels with high specific surface area and physically reactive groups into microfluidic systems for selective molecular interactions is attracting increasing attention. Herein, the reversible capture and release of molecules through host-guest interactions of hydrogel dots in a microfluidic device is reported, which translates the supramolecular chemistry to the microscale conditions under continuous flow. Polyacrylamide (PAAm) hydrogel arrays with grafted ß-cyclodextrin (ß-CD)  modified poly(2-methyl-2-oxazoline) (CD-PMOXA) chains are fabricated by photopolymerization and integrated into a polydimethylsiloxane (PDMS)-on-glass chip. The ß-CD/adamantane (ß-CD/Ada) host-guest complex is confirmed by two dimensional Nuclear Overhauser Effect Spectroscopy NMR (2D NOESY NMR) prior to transfer to microfluidics. Ada-modified molecules are successfully captured by host-guest interaction formed between the CD-PMOXA grafted chains in the hydrogel network and the guest molecule in the solution. Furthermore, the captured molecules are released by perfusing free ß-CD with higher binding affinity than those grafted in the hydrogel array. A small guest molecule adamantane-fluorescein-isothiocyanate (Ada-FITC) and a macromolecular guest molecule (Ada-PMOXA-Cyanine 5 (Cy5)) are separately captured and released for three times with a release ratio up to 46% and 92%, respectively. The reproducible capture and release of functional molecules with different sizes demonstrates the stability of this hydrogel system in microfluidics and will provide an opportunity for future applications.


Subject(s)
Adamantane , Cyclodextrins , Hydrogels/chemistry , Microfluidics , Cyclodextrins/chemistry , Macromolecular Substances/chemistry , Adamantane/chemistry
7.
Molecules ; 27(21)2022 Oct 31.
Article in English | MEDLINE | ID: mdl-36364230

ABSTRACT

Structural analysis and docking studies of three adamantane-linked 1,2,4-triazole N-Mannich bases (1-3) are presented. Compounds 1, 2 and 3 crystallized in the monoclinic P21/c, P21 and P21/n space groups, respectively. Crystal packing of 1 was stabilized by intermolecular C-H⋯O interactions, whereas compounds 2 and 3 were stabilized through intermolecular C-H⋯N, C-H⋯S and C-H⋯π interactions. The energy frameworks for crystal structures of 1-3 were described. The substituent effect on the intermolecular interactions and their contributions were described on the basis of Hirshfeld surface analyses. The 11ß-hydroxysteroid dehydrogenase type 1 (11ß-HSD1) inhibition potential, pharmacokinetic and toxicity profiles of compounds 1-3 were determined using in silico techniques. Molecular docking of the compounds into the 11ß-HSD1 active site showed comparable binding affinity scores (-7.50 to -8.92 kcal/mol) to the 11ß-HSD1 co-crystallized ligand 4YQ (-8.48 kcal/mol, 11ß-HSD1 IC50 = 9.9 nM). The compounds interacted with key active site residues, namely Ser170 and Tyr183, via strong hydrogen bond interactions. The predicted pharmacokinetic and toxicity profiles of the compounds were assessed, and were found to exhibit excellent ADMET potential.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1 , Adamantane , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , Adamantane/chemistry , Molecular Docking Simulation , Mannich Bases , Enzyme Inhibitors/pharmacology
8.
J Chem Inf Model ; 62(17): 4162-4174, 2022 09 12.
Article in English | MEDLINE | ID: mdl-35959540

ABSTRACT

Binding affinity prediction by means of computer simulation has been increasingly incorporated in drug discovery projects. Its wide application, however, is limited by the prediction accuracy of the free energy calculations. The main error sources are force fields used to describe molecular interactions and incomplete sampling of the configurational space. Organic host-guest systems have been used to address force field quality because they share similar interactions found in ligands and receptors, and their rigidity facilitates configurational sampling. Here, we test the binding free energy prediction accuracy for 14 guests with an aromatic or adamantane core and the CB7 host using molecular electron density derived nonbonded force field parameters. We developed a computational workflow written in Python to derive atomic charges and Lennard-Jones parameters with the Minimal Basis Iterative Stockholder method using the polarized electron density of several configurations of each guest in the bound and unbound states. The resulting nonbonded force field parameters improve binding affinity prediction, especially for guests with an adamantane core in which repulsive exchange and dispersion interactions to the host dominate.


Subject(s)
Adamantane , Electrons , Adamantane/chemistry , Computer Simulation , Ligands , Thermodynamics
9.
J Biomater Sci Polym Ed ; 33(14): 1828-1844, 2022 10.
Article in English | MEDLINE | ID: mdl-35686461

ABSTRACT

Nanomedicine has developed as a potential technique for successful cancer therapy. A simple supramolecular self-assembly process is a helpful strategy for generating carrier-free nanodrugs. Mixing photodynamic treatment with chemotherapy has been sought to obtain a high therapeutic impact. In this study, we effectively construct a nanocarrier (CD-Por-PEG: Ada-CPT-Pt(IV)) combined with Carboplatin prodrug (Ada-CPT-Pt(IV)) and photosensitizer porphyrin (CD-Por-PEG) by host-guest interactions to accomplish stimuli-response combination treatment. Supported by greater spatial control of the binding ratio among host-guest molecules, Carboplatin and porphyrin were independently altered with ß-cyclodextrin and adamantane to produce the amphiphilic host-guest combination for sequential self-assembly into therapeutic nanoparticles. The colloidal stability of the produced CD-Por-PEG: Ada-CPT-Pt(IV)-NPs was excellent, with an average hydrodynamic diameter of ∼170 nm. The microscopy images showed that CD-Por-PEG: Ada-CPT-Pt(IV) could aggregate cells and generate ROS after light irradiation (630 nm). Monotherapy had a cytotoxicity three times greater than the CD-Por-PEG: Ada-CPT-Pt(IV) nanoparticles. Studies in mice carrying SUNE1 nasopharyngeal tumours showed that nanoparticles effectively suppressed tumour development without causing systemic damage in this examination. The current self-assembly nanosystem makes precise control over the photosensitizer and drug loading possible ratio. It reduces the systemic adverse toxicity issues of drugs carrier, making this system ideal for nasopharyngeal cancer treatment.


Subject(s)
Adamantane , Nanoparticles , Nasopharyngeal Neoplasms , Porphyrins , Prodrugs , beta-Cyclodextrins , Adamantane/chemistry , Animals , Carboplatin , Cell Line, Tumor , Mice , Nanoparticles/chemistry , Nasopharyngeal Neoplasms/drug therapy , Photosensitizing Agents/pharmacology , Porphyrins/chemistry , Prodrugs/chemistry , Prodrugs/pharmacology , Reactive Oxygen Species , beta-Cyclodextrins/chemistry
10.
ACS Macro Lett ; 11(1): 135-139, 2022 01 18.
Article in English | MEDLINE | ID: mdl-35574794

ABSTRACT

The fluorescent organic 2,5,8-tris((adamantan-1-yl)-methoxy)-heptazine (HTZ-Ad) was solubilized in water by inclusion of adamantane groups into free ß-cyclodextrins or a cyclodextrin shell of glyconanoparticles. These glyconanoparticles with average diameters between 40 and 60 nm result from the self-assembly of polystyrene-block-ß-cyclodextrin copolymers. Under UV irradiation at 365 nm, the modified nanoparticles exhibit fluorescence emission in aqueous media as well as in their adsorbed state. This constitutes the first spectroscopic characterization of a trialkoxyheptazine in aqueous medium. The specific binding of the glyconanoparticles to a surface was achieved via host-guest interactions with an electrochemically generated poly(pyrrole-adamantane) film. An interdigitated microelectrode modified with poly(pyrrole-adamantane) film and glyconanoparticles was incubated in HTZ-Ad, resulting in a substrate with spatially controlled fluorescence. The same modified electrode was incubated with an aqueous suspension of glyconanoparticles previously functionalized by HTZ-Ad, resulting in a fluorescent 3D assembly.


Subject(s)
Adamantane , Cyclodextrins , Adamantane/chemistry , Cyclodextrins/chemistry , Fluorescence , Pyrroles , Water
11.
J Magn Reson ; 340: 107231, 2022 07.
Article in English | MEDLINE | ID: mdl-35605465

ABSTRACT

The 13C signals of adamantane are used as a chemical shift standard for solid-state NMR. Its chemical shifts are measured to greater accuracy than previously reported and over a temperature range from -2 to 70 °C. Combining the chemical shifts of adamantane's two NMR signals gives an accurate chemical shift over the whole temperature range without need for measuring the temperature directly. The difference between the chemical shifts gives the approximate temperature. The chemical shift of the adamantane CH signal at 25 °C is 37.777, σ = 0.003 ppm.


Subject(s)
Adamantane , Adamantane/chemistry , Magnetic Resonance Spectroscopy
12.
ChemistryOpen ; 11(10): e202200031, 2022 10.
Article in English | MEDLINE | ID: mdl-35243816

ABSTRACT

Introduction of adamantane moieties on diamondoids such as adamantane, 2-azaadamantane or diamantane by amide formation and reduction to the corresponding amine was performed in a straightforward and easy way by amidation under Schotten-Baumann conditions and reduction with BH3 ⋅ THF. The obtained amides and amines were studied in terms of structural properties towards the perspective of transformation into nanodiamonds. Crystal structure and dynamic NMR experiments of the most crowded amide obtained gave structural insights into the effect of bulkiness and steric strain on out-of-planarity of amide bonds (16.0°) and the kinetics and thermodynamics of amide bond rotation (ΔG≠ 298K =11.5-13.3 kcal ⋅ mol-1 ).


Subject(s)
Adamantane , Nanodiamonds , Adamantane/chemistry , Amides/chemistry , Amines/chemistry , Nanodiamonds/chemistry , Thermodynamics
13.
Dalton Trans ; 51(11): 4284-4296, 2022 Mar 15.
Article in English | MEDLINE | ID: mdl-35191438

ABSTRACT

4,6,10-Trihydroxy-1,4,6,10-tetraazaadamantane (TAAD) has been shown to form a stable Fe(IV) complex having a diamantane cage structure, in which the metal center is coordinated by three oxygen atoms of the deprotonated ligand. The complex was characterized by X-ray diffraction analysis, HRMS, NMR, FT-IR, Mössbauer spectroscopy and DFT calculations, which supported the d4 configuration of iron. The Fe(IV)-TAAD complex showed excellent performance in dioxygen activation under mild conditions serving as a mimetic of the thiol oxidase enzyme. The nucleophilicity of the bridgehead nitrogen atom in TAAD provides a straightforward way for the conjugation of Fe(IV)-TAAD complexes to various functional molecules. Using this approach, steroidal and peptide molecules having an iron(IV) label have been prepared for the first time. In addition, the Fe(IV)-TAAD complex was covalently bound to a polystyrene matrix and the resulting material was shown to serve as a heterogeneous catalyst for aerobic oxidation of thiols to disulfides.


Subject(s)
Adamantane/chemistry , Iron Compounds/chemistry , Oxygen/chemistry , Adamantane/chemical synthesis , Crystallography, X-Ray , Density Functional Theory , Iron Compounds/chemical synthesis , Ligands , Models, Molecular
14.
ACS Appl Mater Interfaces ; 14(2): 2564-2577, 2022 Jan 19.
Article in English | MEDLINE | ID: mdl-34981928

ABSTRACT

Supramolecular chemistry provides huge potentials and opportunities in agricultural pest management. In an attempt to develop highly bioactive, eco-friendly, and biocompatible supramolecular complexes for managing intractable plant bacterial diseases, herein, a type of interesting adamantane-functionalized 1,3,4-oxadiazole was rationally prepared to facilitate the formation of supramolecular complexes via ß-cyclodextrin-adamantane host-guest interactions. Initial antibacterial screening revealed that most of these adamantane-decorated 1,3,4-oxadiazoles were obviously bioactive against three typically destructive phytopathogens. The lowest EC50 values could reach 0.936 (III18), 0.889 (III18), and 2.10 (III19) µg/mL against the corresponding Xanthomonas oryzae pv. oryzae (Xoo), Xanthomonas axonopodis pv. citri (Xac), and Pseudomonas syringae pv. actinidiae (Psa). Next, the representative supramolecular binary complex III18@ß-CD (binding mode 1:1) was successfully fabricated and characterized by 1H nuclear magnetic resonance (NMR), isothermal titration calorimetry (ITC), high-resolution mass spectrometry (HRMS), dynamic light scattering (DLS), and transmission electron microscopy (TEM). Eventually, correlative water solubility and foliar surface wettability were significantly improved after the formation of host-guest assemblies. In vivo antibacterial evaluation found that the achieved supramolecular complex could distinctly alleviate the disease symptoms and promote the control efficiencies against rice bacterial blight (from 34.6-35.7% (III18) to 40.3-43.6% (III18@ß-CD)) and kiwi canker diseases (from 41.0-42.3% (III18) to 53.9-68.0% (III18@ß-CD)) at 200 µg/mL (active ingredient). The current study can provide a feasible platform and insight for constructing biocompatible supramolecular assemblies for managing destructive bacterial infections in agriculture.


Subject(s)
Adamantane/pharmacology , Anti-Bacterial Agents/pharmacology , Bacterial Infections/drug therapy , Biocompatible Materials/pharmacology , Oxadiazoles/pharmacology , beta-Cyclodextrins/pharmacology , Adamantane/chemistry , Anti-Bacterial Agents/chemical synthesis , Anti-Bacterial Agents/chemistry , Biocompatible Materials/chemical synthesis , Biocompatible Materials/chemistry , Materials Testing , Microbial Sensitivity Tests , Molecular Structure , Oryza/microbiology , Oxadiazoles/chemistry , Pseudomonas/drug effects , Xanthomonas/drug effects , beta-Cyclodextrins/chemistry
15.
Biochim Biophys Acta Biomembr ; 1864(1): 183793, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34655545

ABSTRACT

Mycobacterial membrane protein large 3 (Mmpl3) as a trehalose monomycolate lipid transporter contributes to cell wall biosynthesis. Inhibition of Mmpl3 can suppress cell growth and lead to mycobacterial death. SQ109 is a hydrophobic inhibitor of Mmpl3. We have devised a detergent-free strategy to characterize the SQ109/Mmpl3 interaction using the Native Cell Membrane Nanoparticles (NCMN) system, a new method for extracting membrane proteins that better retains native lipids. The homogeneity of the Mmpl3 NCMN particles was confirmed with electron microscopy. The hydrophobic protein-ligand interaction analysis shown for Mmpl3 using the NCMN system may broadly apply to other membrane proteins.


Subject(s)
Adamantane/analogs & derivatives , Bacterial Proteins/chemistry , Carrier Proteins/chemistry , Ethylenediamines/chemistry , Membrane Transport Proteins/chemistry , Mycobacterium/chemistry , Adamantane/chemistry , Bacterial Proteins/genetics , Carrier Proteins/genetics , Cell Membrane/chemistry , Lipids/chemistry , Lipids/genetics , Membrane Proteins/chemistry , Membrane Proteins/genetics , Membrane Transport Proteins/genetics , Mycobacterium/genetics , Nanoparticles/chemistry
16.
Int J Mol Sci ; 22(23)2021 Nov 24.
Article in English | MEDLINE | ID: mdl-34884480

ABSTRACT

Cyclin-dependent kinases (CDKs) play an important role in the cell-division cycle. Synthetic inhibitors of CDKs are based on 2,6,9-trisubstituted purines and are developed as potential anticancer drugs; however, they have low solubility in water. In this study, we proved that the pharmaco-chemical properties of purine-based inhibitors can be improved by appropriate substitution with the adamantane moiety. We prepared ten new purine derivatives with adamantane skeletons that were linked at position 6 using phenylene spacers of variable geometry and polarity. We demonstrated that the adamantane skeleton does not compromise the biological activity, and some of the new purines displayed even higher inhibition activity towards CDK2/cyclin E than the parental compounds. These findings were supported by a docking study, which showed an adamantane scaffold inside the binding pocket participating in the complex stabilisation with non-polar interactions. In addition, we demonstrated that ß-cyclodextrin (CD) increases the drug's solubility in water, although this is at the cost of reducing the biochemical and cellular effect. Most likely, the drug concentration, which is necessary for target engagement, was decreased by competitive drug binding within the complex with ß-CD.


Subject(s)
Adamantane/chemistry , Antineoplastic Agents/pharmacology , Cyclin-Dependent Kinase 2/antagonists & inhibitors , Protein Kinase Inhibitors/pharmacology , Purines/chemistry , beta-Cyclodextrins/chemistry , Antineoplastic Agents/chemistry , Humans , K562 Cells , MCF-7 Cells , Structure-Activity Relationship
17.
Inorg Chem ; 60(23): 17783-17796, 2021 Dec 06.
Article in English | MEDLINE | ID: mdl-34762413

ABSTRACT

PtmU3 is a newly identified nonheme diiron monooxygenase, which installs a C-5 ß-hydroxyl group into the C-19 CoA-ester intermediate involved in the biosynthesis of unique diterpene-derived scaffolds of platensimycin and platencin. PtmU3 possesses a noncanonical diiron active site architecture of a saturated six-coordinate iron center and lacks the µ-oxo bridge. Although the hydroxylation process is a simple reaction for nonheme mononuclear iron-dependent enzymes, how PtmU3 employs the diiron center to catalyze the H-abstraction and OH-rebound is still unknown. In particular, the electronic characteristic of diiron is also unclear. To understand the catalytic mechanism of PtmU3, we constructed two reactant models in which both the Fe1II-Fe2III-superoxo and Fe1II-Fe2IV═O are considered to trigger the H-abstraction and performed a series of quantum mechanics/molecular mechanics calculations. Our calculation results reveal that PtmU3 is a special monooxygenase, that is, both atoms of the dioxygen molecule can be incorporated into two molecules of the substrate by the successive reactions. In the first-round reaction, PtmU3 uses the Fe1II-Fe2III-superoxo to install a hydroxyl group into the substrate, generating the high-reactive Fe1II-Fe2IV═O complex. In the second-round reaction, the Fe1II-Fe2IV═O species is responsible for the hydroxylation of another molecule of the substrate. In the diiron center, Fe2 adopts the high spin state (S = 5/2) during the catalysis, whereas for Fe1, in addition to its structural role, it may also play an assistant role for Fe1 catalysis. In the two successive OH-installing steps, the H-abstraction is always the rate-liming step. E241 and D308 not only act as bridging ligands to connect two Fe ions but also take part in the electron reorganization. Owing to the high reactivity of Fe1II-Fe2IV═O compared to Fe1II-Fe2III-superoxo, besides the C5-hydroxylation, the C3- or C18-hydroxylation was also calculated to be feasible.


Subject(s)
Adamantane/metabolism , Aminobenzoates/metabolism , Anilides/metabolism , Density Functional Theory , Mixed Function Oxygenases/metabolism , Molecular Dynamics Simulation , Adamantane/chemistry , Aminobenzoates/chemistry , Anilides/chemistry , Biocatalysis , Hydroxylation , Molecular Structure
18.
Chem Commun (Camb) ; 57(74): 9446-9449, 2021 Sep 16.
Article in English | MEDLINE | ID: mdl-34528969

ABSTRACT

Biodegradable supramolecular micelles were prepared exploiting the host-guest interaction of cyclodextrin and adamantane. Cyclodextrin-initiated polypeptides acted as the hydrophilic corona, whereas adamantane-terminated polycaprolactones served as the hydrophobic core.


Subject(s)
Adamantane/chemistry , Cyclodextrins/chemistry , Peptides/chemistry , Polyesters/chemistry , Hydrophobic and Hydrophilic Interactions , Macromolecular Substances/chemistry , Micelles , Molecular Structure
19.
Int J Biol Macromol ; 191: 139-151, 2021 Nov 30.
Article in English | MEDLINE | ID: mdl-34543626

ABSTRACT

One way to enhance the poor mechanical properties of the self-healing hydrogels based on host-guest (HG) interaction is employing the dual cross-linking method. Here, the alginate-based hydrogels based on HG complexation were prepared through the modification of alginate (ALG) polysaccharide with beta-cyclodextrin (ßCD) and adamantane (Ad) as host and guest groups with different grafting values, respectively. The porous structure was confirmed for all ALG-CD:ALG-Ad hydrogels. The average pore size of ALG-CD1:ALG-Ad1 hydrogel cross-linked by HG interactions was 288 µm. Mechanical properties of the alginate-based HG hydrogels were improved by incorporating Ca2+ ions in their structure through dual cross-linking methodology. The maximum modulus of the porous dual-crosslinked hydrogel was reached up to 6500 Pa. The healing time of less than 5 s was obtained for the alginate-based hydrogels. The fabricated hydrogels can be used in 3D printing, tissue engineering, and drug delivery systems due to their biocompatibility and shear-thinning behavior.


Subject(s)
Alginates/chemistry , Hydrogels/chemistry , Mechanical Phenomena , Adamantane/chemistry , Calcium/chemistry , Cross-Linking Reagents/chemistry , Porosity , beta-Cyclodextrins/chemistry
20.
Molecules ; 26(17)2021 Sep 02.
Article in English | MEDLINE | ID: mdl-34500764

ABSTRACT

The solid-state structural analysis and docking studies of three adamantane-linked 1,2,4-triazole derivatives are presented. Crystal structure analyses revealed that compound 2 crystallizes in the triclinic P-1 space group, while compounds 1 and 3 crystallize in the same monoclinic P21/c space group. Since the only difference between them is the para substitution on the aryl group, the electronic nature of these NO2 and halogen groups seems to have no influence over the formation of the solid. However, a probable correlation with the size of the groups is not discarded due to the similar intermolecular disposition between the NO2/Cl substituted molecules. Despite the similarities, CE-B3LYP energy model calculations show that pairwise interaction energies vary between them, and therefore the total packing energy is affected. HOMO-LUMO calculated energies show that the NO2 group influences the reactivity properties characterizing the molecule as soft and with the best disposition to accept electrons. Further, in silico studies predicted that the compounds might be able to inhibit the 11ß-HSD1 enzyme, which is implicated in obesity and diabetes. Self- and cross-docking experiments revealed that a number of non-native 11ß-HSD1 inhibitors were able to accurately dock within the 11ß-HSD1 X-ray structure 4C7J. The molecular docking of the adamantane-linked 1,2,4-triazoles have similar predicted binding affinity scores compared to the 4C7J native ligand 4YQ. However, they were unable to form interactions with key active site residues. Based on these docking results, a series of potentially improved compounds were designed using computer aided drug design tools. The docking results of the new compounds showed similar predicted 11ß-HSD1 binding affinity scores as well as interactions to a known potent 11ß-HSD1 inhibitor.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenase Type 1/antagonists & inhibitors , Adamantane/pharmacology , Enzyme Inhibitors/pharmacology , Molecular Docking Simulation , Triazoles/pharmacology , 11-beta-Hydroxysteroid Dehydrogenase Type 1/metabolism , Adamantane/chemistry , Crystallography, X-Ray , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Humans , Molecular Structure , Triazoles/chemistry
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