scholarly journals Enhanced Stability and Bioactivity of Natural Anticancer Topoisomerase I Inhibitors through Cyclodextrin Complexation

Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1609
Author(s):  
Víctor González-Ruiz ◽  
Ángel Cores ◽  
Olmo Martín-Cámara ◽  
Karen Orellana ◽  
Víctor Cervera-Carrascón ◽  
...  
Keyword(s):  
Inclusion Complexes ◽  
Topoisomerase I ◽  
Chemical Shifts ◽  
Resonance Spectroscopy ◽  
Human Neuroblastoma ◽  
Anti Cancer ◽  
Pharmacokinetic Properties ◽  
Cyclodextrin Cavity ◽  
Luotonin A ◽  
Phase Liquid

The use of cyclodextrins as drug nano-carrier systems for drug delivery is gaining importance in the pharmaceutical industry due to the interesting pharmacokinetic properties of the resulting inclusion complexes. In the present work, complexes of the anti-cancer alkaloids camptothecin and luotonin A have been prepared with β-cyclodextrin and hydroxypropyl-β-cyclodextrin. These cyclodextrin complexes were characterized by nuclear magnetic resonance spectroscopy (NMR). The variations in the 1H-NMR and 13C-NMR chemical shifts allowed to establish the inclusion modes of the compounds into the cyclodextrin cavities, which were supported by docking and molecular dynamics studies. The efficiency of the complexation was quantified by UV-Vis spectrophotometry and spectrofluorimetry, which showed that the protonation equilibria of camptothecin and luotonin A were drastically hampered upon formation of the inclusion complexes. The stabilization of camptothecin towards hydrolysis inside the cyclodextrin cavity was verified by the quantitation of the active lactone form by reverse phase liquid chromatography fluorimetric detection, both in basic conditions and in the presence of serum albumin. The antitumor activity of luotonin A and camptothecin complexes were studied in several cancer cell lines (breast, lung, hepatic carcinoma, ovarian carcinoma and human neuroblastoma) and an enhanced activity was found compared to the free alkaloids, particularly in the case of hydroxypropyl-β-cyclodextrin derivatives. This result shows that the cyclodextrin inclusion strategy has much potential towards reaching the goal of employing luotonin A or its analogues as stable analogues of camptothecin.

scholarly journals CYCLODEXTRIN INCLUSION COMPLEXES OF PHARMACEUTICALLY ACTIVE DERIVATIVES OF THE CYTISINE ALKALOID AND THEIR HEMORHEOLOGICAL ACTIVITY

2021 ◽  
pp. 72-87
Author(s):  
G.K. Mukusheva ◽  
◽  
A.R. Zhasymbekova ◽  
Z.B. Satpaeva ◽  
Е.V. Minayeva ◽  
...  
Keyword(s):  
Inclusion Complexes ◽  
Chemical Shifts ◽  
Differential Scanning Calorimetric ◽  
Supramolecular System ◽  
Alkaloid Cytisine ◽  
Two Samples ◽  
Cyclodextrin Cavity ◽  
Cytisine Alkaloid ◽  
Derivatives Of

The alkaloid cytisine is of great importance for modern pharmacological studies. This alkaloid can be used as a component of the supramolecular system with cyclic oligosaccharides, namely β-cyclodextrins, which have a truncated cone-shaped molecule with internal protons Н3 and Н5 and external ones Н2 and Н4. The aim of the work is to obtain inclusion complexes of pharmaceutically active derivatives of the alkaloid cytisine. The inclusion complexes of cytisine alkaloid derivatives with β-CD and 2-HP-β-CD were obtained by the coprecipitation method. Thermogravimetric, differential thermal, and differential scanning calorimetric analyzes were performed. It was shown that inclusion complexes of substrate with cyclodextrin cavity of receptors were formed. The greatest change in the chemical shifts of protons during the formation of supra-molecular complexes occurs with the internal protons H-3 and H-5 of the cyclodextrin cavity. All calculated values are in good agreement with experimental data. The prepa-ration of supramolecular complexes has been proven using a variety of physicochemical methods of analysis. According to DSC data, the process of complexes destruction in the temperature range of 30-610°C was studied in comparison with the data of the initial cyclodextrin. The hemorheological effects of the investigated samples were studied in vitro. Among four samples studied, two samples showed the ability to reduce blood viscosity in vitro in the blood hyperviscosity model.

scholarly journals Physicochemical properties and structural dynamics of organic–inorganic hybrid [NH3(CH2)3NH3]ZnX4 (X = Cl and Br) crystals

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ae Ran Lim ◽  
Sun Ha Kim ◽  
Yong Lak Joo
Keyword(s):  
Structural Dynamics ◽  
Chemical Shifts ◽  
Lattice Relaxation ◽  
Magic Angle Spinning ◽  
Spin Lattice Relaxation ◽  
Resonance Spectroscopy ◽  
Magic Angle ◽  
Scanning Calorimetry ◽  
Inorganic Hybrid ◽  
Halogen Atoms

AbstractThe physical properties of the organic–inorganic hybrid crystals having the formula [NH3(CH2)3NH3]ZnX4 (X = Cl, Br) were investigated. The phase transition temperatures (TC; 268K for Cl and 272K for Br) of the two crystals bearing different halogen atoms in their skeletons were determined through differential scanning calorimetry. The thermodynamic properties of the two crystals were investigated through thermogravimetric analysis. The structural dynamics, particularly the role of the [NH3(CH2)3NH3] cation, were probed through 1H and 13C magic-angle spinning nuclear magnetic resonance spectroscopy as a function of temperature. The 1H and 13C NMR chemical shifts did not show any changes near TC. In addition, the 1H spin–lattice relaxation time (T1ρ) varied with temperature, whereas the 13C T1ρ values remained nearly constant at different temperatures. The T1ρ values of the atoms in [NH3(CH2)3NH3]ZnCl4 were higher than those in [NH3(CH2)3NH3]ZnBr4. The observed differences in the structural dynamics obtained from the chemical shifts and T1ρ values of the two compounds can be attributed to the differences in the bond lengths and halogen atoms. These findings can provide important insights or potential applications of these crystals.

Studies of specifically fluorinated carbohydrates. Part II. Nuclear magnetic resonance studies of pentopyranosyl fluoride derivatives

1969 ◽  
Vol 47 (1) ◽  
pp. 19-30 ◽  
Author(s):  
L. D. Hall ◽  
J. F. Manville
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Chemical Shifts ◽  
Coupling Constants ◽  
Resonance Spectroscopy ◽  
Magnetic Resonance Studies ◽  
Conformational Model ◽  
Nuclear Magnetic

Detailed studies, by 1H and 19F nuclear magnetic resonance spectroscopy, of a series of fully esterified pentopyranosyl fluorides, show that all such derivatives favor that conformer in which the fluorine substituent is axially oriented. This conclusion is supported by separate considerations of the vicinal and geminal19F–1H and 1H–1H coupling constants, of the long-range (4J) 1H–1H and 19F–1H coupling constants and of the 19F chemical shifts. The limitations of the above conformational model are discussed.

scholarly journals CHARACTERISATION OF INCLUSION COMPLEXES BETWEEN BIFONAZOLE AND DIFFERENT CYCLODEXTRINS IN SOLID AND SOLUTION STATE

2017 ◽  
Vol 36 (1) ◽  
pp. 81 ◽  
Author(s):  
Hajnal Kelemen ◽  
Angella Csillag ◽  
Gabriel Hancu ◽  
Blanka Székely-Szentmiklósi ◽  
Ibolya Fülöp ◽  
...  
Keyword(s):  
Inclusion Complexes ◽  
Binary Systems ◽  
Pharmaceutical Formulations ◽  
2D Nmr ◽  
Local Drug Delivery ◽  
Stable Complex ◽  
Resonance Spectroscopy ◽  
Scanning Calorimetry ◽  
2D Nmr Spectroscopy ◽  
Major Drawback

The aim of this study is to confirm the formation of inclusion complexes between bifonazole (BFZ) and different cyclodextrin (CD) derivatives. Bifonazole, an imidazole antifungal derivative,is a very hydrophobic compound, which is a major drawback in obtaining topical pharmaceutical formulations with optimal bioavailability. Cyclodextrins may increase local drug delivery by enhancing the drug release and/or permeation. The binary systems between bifonazole and cyclodextrins were prepared in two molar ratios by physical-mixture methods.The physicochemical properties of these complexes were studied by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR) methods. Results showed favourable molecular interaction between the components, in solid state and in solution. 1H NMR -CD titrations and molecular modelling study showed that the most stable complex was obtained when using γ-CD. The Job’s method and 2D NMR spectroscopy sustain the 2:1 stoichiometry of the BFZ:γ-CD complex.

scholarly journals Study of the biologically active acyclic ureas by nuclear magnetic resonance

2020 ◽  
Vol 100 (4) ◽  
pp. 60-74
Author(s):  
А.А. Bakibaev ◽  
◽  
М.Zh. Sadvakassova ◽  
V.S. Malkov ◽  
R.Sh. Еrkasov ◽  
...  
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Functional Groups ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Biologically Active ◽  
Resonance Spectroscopy ◽  
13C Nmr Spectra ◽  
Nuclear Magnetic

A wide variety of acyclic ureas comprising alkyl, arylalkyl, acyl, and aryl functional groups are investigated by nuclear magnetic resonance spectroscopy. In general, spectral characteristics of more than 130 substances based on acyclic ureas dissolved in deuterated dimethyl sulfoxide at room temperature are studied. The re-sults obtained based on the studies of 1H and 13C NMR spectra of urea and its N-alkyl-, N-arylalkyl-, N-aryl- and 1,3-diaryl derivatives are presented, and the effect of these functional groups on the chemical shifts in carbonyl and amide moieties in acyclic urea derivatives is discussed. An introduction of any type of substitu-ent (electron-withdrawing or electron-donating) into urea molecule is stated to result in a strong upfield shift in 13C NMR spectra relatively to unsubstituted urea. A strong sensitivity of NH protons to the presence of acyl and aryl groups in nuclear magnetic resonance spectra is pointed out. In some cases, qualitative depend-encies between the chemical shifts in the NMR spectra and the structure of the studied acyclic ureas are re-vealed. A summary of the results on chemical shifts in the NMR spectra of the investigated substances allows determining the ranges of chemical shift variations of the key protons and carbon atoms in acyclic ureas. The literature describing the synthesis procedures are provided. The results obtained significantly expand the methods of reliable identification of biologically active acyclic ureas and their metabolites that makes it promising to use NMR spectroscopy both in biochemistry and in clinical practice.

Synthesis and topoisomerase I inhibitory properties of luotonin A analogues

2004 ◽  
Vol 12 (23) ◽  
pp. 6287-6299 ◽  
Author(s):  
Ali Cagir ◽  
Brian M. Eisenhauer ◽  
Rong Gao ◽  
Shannon J. Thomas ◽  
Sidney M. Hecht
Keyword(s):  
Topoisomerase I ◽  
Luotonin A

scholarly journals PL1.2 Multiparametric assessment of factors influencing 2 HG accumulation in diffuse brain gliomas

2019 ◽  
Vol 21 (Supplement_3) ◽  
pp. iii1-iii2
Author(s):  
L Nichelli ◽  
F Branzoli ◽  
R Valabregue ◽  
L Capelle ◽  
C Ottolenghi ◽  
...  
Keyword(s):  
Tumor Volume ◽  
Treated Patient ◽  
Gas Chromatography Mass Spectrometry ◽  
Resonance Spectroscopy ◽  
Genetic Profile ◽  
Radiological Change ◽  
Cellular Density ◽  
Anti Cancer ◽  
Hg Accumulation

Abstract BACKGROUND 2-hydroxyglutarate (2HG) can be detected non-invasively in IDH-mutant gliomas by in vivo magnetic resonance spectroscopy (MRS). We investigated factors affecting 2 HG accumulation and explored the prognostic value of 2 HG detection in IDH mutant gliomas and 2 HG variations during anti-cancer therapies. MATERIAL AND METHODS We prospectively scanned by MEGA-PRESS 70 glioma patients (24 before surgery and 46 IDH mutant operated glioma) and measured 2HG. CRLB cut-off was 50%. We followed up 9 IDH mutant patients during radiotherapy and chemotherapy.We analyzed radiological parameters (tumor and cystic/necrotic volumes, fractions of VOI filled with tumor, spectroscopic profile, “infiltrative” versus “expansive” morphology, contrast-enhancement) and genetic profile (IDH1, IDH2, 1p19q codeletion). 2HG concentrations in plasma, urine, and surgical obtained samples were measured by gas chromatography-mass spectrometry (GC-MS). RESULTS MEGA-PRESS sequence detected 2HG with a sensitivity of 95% in untreated patients, and of 69% in pre-treated patient. Positive predictive value was 100% in both groups. 2HG was lower in pre-treated IDH mutant gliomas (1.1 versus 2.3 mM, P=0.02) and decreased rapidly during radiotherapy and chemotherapy before any radiological change. 2HG detection was positively correlated with tumor volume (P=0.02), choline measurements (r=0.58 P<0.0001), cellular density (measured by restricted diffusivity, Pearson r -0.40 P=0.01), “expansive” presentation, mutated reads/total reads ratio by NGS and was inversely correlated with Myo-inositol (Pearson R -0.29 P=0.03) and cystic/necrotic areas (P=0.04). 2HG by MRS positively correlated with urine 2HG (r=0.80 P=0.003). 2 HG was higher in IDH2 mutant (4.7 versus 2.4 Mm, P=0.02) and lower in non R132H IDH1 mutant (1.12 mM P=0.004). Among IDH mutant glioma patients, 2 HG detection was associated with longer survival (HR 0.09; 95%CI 0.018–0.52). CONCLUSION Tumor volume, cellular density, previous radio- and chemotherapy and genetic features determine 2 HG detection in IDH mutant gliomas. 2 HG detection is associated with better outcome and can be reliably monitored during anti-cancer treatments.

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