Proton nuclear magnetic resonance studies of nucleosides: hindered internal rotation in N-dimethylaminomethylene derivatives of adenosine, guanosine, and cytidine

1993 ◽  
Vol 71 (7) ◽  
pp. 1006-1009 ◽  
Author(s):  
Emmanuel Yaw Osei-Twum
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
High Resolution ◽  
Internal Rotation ◽  
Considerable Effect ◽  
Proton Nuclear Magnetic Resonance ◽  
Magnetic Resonance Studies ◽  
H Nmr ◽  
Derivatives Of ◽  
Coalescence Temperature

Studies of the internal rotation about the C—N bond of the dimethylaminomethylene (DMAM) group of DMAM-adenosine, 1, DMAM-guanosine, 2, and DMAM-cytidine, 3, was determined by high-resolution 1H NMR spectroscopy. Arrhenius plots (ln k = ln A − Ea/RT) were used to determine the barriers to internal rotation, Ea, of the compounds. They were found to be 58.0 ± 2.4 kJ mol−1, 71.2 ± 1.4 kJ mol−1, and 62.8 ± 2.4 kJ mol−1 for 1, 2, and 3, respectively. At the same time the coalescence temperatures, tc, for the compounds were determined and found to be 93.5 °C for 1, 124.7 °C for 2, and 119.6 °C for 3 in DMSO. In D2O, compound 1 was found to have a tc of 104.5 °C. The compound decomposed so rapidly at this temperature that the barrier to internal rotation could not be determined. The results indicate that the oxo function in the nucleobase has a considerable effect on the barrier to internal rotation and coalescence temperature.

Nuclear Magnetic Resonance Studies of Substituted 4-Hydroxy-5-phosphinyl-2-imidazolidinones

1982 ◽  
Vol 36 (4) ◽  
pp. 466-471 ◽  
Author(s):  
John A. Mikroyannidis ◽  
Alexandros K. Tsolis
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Nmr Spectra ◽  
Parent Compound ◽  
Proton Nuclear Magnetic Resonance ◽  
Magnetic Resonance Studies ◽  
Aqueous Sodium ◽  
H Nmr ◽  
Nuclear Magnetic

The proton nuclear magnetic resonance (NMR) spectra of some substituted 4-hydroxy-5-phosphinyl-2-imidazolidinones have been studied. The predominance of the cis stereoisomer of these compounds has been also established by 1H NMR spectroscopy. The spectral effects produced by the introduction of the phosphinyl group on the parent compound and by reaction of the substituted 4-hydroxy-5-phosphinyl-2-imidazolidinones with aqueous sodium deuteroxide are discussed. In addition, it has been established by 1H NMR that the product obtained from the reaction of 2-hydroxy-2-(diethoxyphosphinyl)ethanal with N-methylurea was a mixture of 18.2% 1-methyl- and of 81.8% 3-methyl-4-hydroxy-5-diethoxyphosphinyl-2-imidazolidinone.

Use of high-resolution proton nuclear magnetic resonance spectroscopy for rapid multi-component analysis of urine.

1984 ◽  
Vol 30 (3) ◽  
pp. 426-432 ◽  
Author(s):  
J R Bales ◽  
D P Higham ◽  
I Howe ◽  
J K Nicholson ◽  
P J Sadler
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
High Resolution ◽  
1H Nmr ◽  
1H Nmr Spectroscopy ◽  
Proton Nuclear Magnetic Resonance ◽  
Resonance Spectroscopy ◽  
Simple Method ◽  
Nuclear Magnetic

Abstract Numerous low-Mr metabolites--including creatinine, citrate, hippurate, glucose, ketone bodies, and various amino acids--have been identified in 400- and 500-MHz proton nuclear magnetic resonance (1H NMR) spectra of intact human urine. The presence of many of these was related to the specific condition of the donors: humans in different physiological states (resting, fasting, or post-exercise) and pathological conditions (e.g., diabetes mellitus, cadmium-induced renal dysfunction). We have also monitored the metabolism of simple nonendogenous compounds (methanol and ethanol) and of acetaminophen. The pH-dependencies of the NMR chemical shifts of some urine components are reported. Our studies show that high-resolution 1H NMR spectroscopy provides a fast, simple method for "fingerprint" identification of urinary compounds. In some cases, analytes can be quantified by standard additions or by comparing integrated peak areas for the metabolites with those for creatinine. Determinations of creatinine by 1H NMR spectroscopy compared well with those by an independent chemical assay based on the Jaffé reaction.

High resolution nuclear magnetic resonance studies of platinum(II) – guanosine-5′-monophosphate interactions in aqueous solutions

1981 ◽  
Vol 59 (23) ◽  
pp. 3297-3302 ◽  
Author(s):  
Moschos Polissiou ◽  
Minh Tan Phan Viet ◽  
Maurice St-Jacques ◽  
Theophile Theophanides
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
High Resolution ◽  
Aqueous Solutions ◽  
Conformational Changes ◽  
Coupling Constant ◽  
Magnetic Resonance Studies ◽  
H Nmr ◽  
Nmr Study ◽  
Ribose Moiety

A detailed 400 MHz 1H nmr study was carried out on platinum complexation products of GMP by K2PtCl4. Coupling constant values show that platination on N7 induces a conformational change on the ribose moiety: the 3E form of the ring and the gt conformer about the C(4′)—C(5′) bond are favoured upon complexation. The results are compared to the conformational changes induced by N7 protonation and methylation.

scholarly journals 1H Nuclear Magnetic Resonance: A Future Approach to the Metabolic Profiling of Psychedelics in Human Biofluids?

2021 ◽  
Vol 12 ◽  
Author(s):  
Sylvana Vilca-Melendez ◽  
Malin V. Uthaug ◽  
Julian L. Griffin
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Metabolic Profiling ◽  
Proton Nuclear Magnetic Resonance ◽  
Future Directions ◽  
H Nmr ◽  
Nuclear Magnetic ◽  
Psychedelic Research

While psychedelics may have therapeutic potential for treating mental health disorders such as depression, further research is needed to better understand their biological effects and mechanisms of action when considering the development of future novel therapy approaches. Psychedelic research could potentially benefit from the integration of metabonomics by proton nuclear magnetic resonance (1H NMR) spectroscopy which is an analytical chemistry-based approach that can measure the breakdown of drugs into their metabolites and their metabolic consequences from various biofluids. We have performed a systematic review with the primary aim of exploring published literature where 1H NMR analysed psychedelic substances including psilocin, lysergic acid diethylamide (LSD), LSD derivatives, N,N-dimethyltryptamine (DMT), 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and bufotenin. The second aim was to assess the benefits and limitations of 1H NMR spectroscopy-based metabolomics as a tool in psychedelic research and the final aim was to explore potential future directions. We found that the most current use of 1H NMR in psychedelic research has been for the structural elucidation and analytical characterisation of psychedelic molecules and that no papers used 1H NMR in the metabolic profiling of biofluids, thus exposing a current research gap and the underuse of 1H NMR. The efficacy of 1H NMR spectroscopy was also compared to mass spectrometry, where both metabonomics techniques have previously shown to be appropriate for biofluid analysis in other applications. Additionally, potential future directions for psychedelic research were identified as real-time NMR, in vivo1H nuclear magnetic resonance spectroscopy (MRS) and 1H NMR studies of the gut microbiome. Further psychedelic studies need to be conducted that incorporate the use of 1H NMR spectroscopy in the analysis of metabolites both in the peripheral biofluids and in vivo to determine whether it will be an effective future approach for clinical and naturalistic research.

Serum analysis by1H Nuclear Magnetic Resonance spectroscopy: a new tool for distinguishing neuromyelitis optica from multiple sclerosis

2013 ◽  
Vol 20 (5) ◽  
pp. 558-565 ◽  
Author(s):  
F-M Moussallieh ◽  
K Elbayed ◽  
JB Chanson ◽  
G Rudolf ◽  
M Piotto ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Nuclear Magnetic Resonance ◽  
Nmr Spectroscopy ◽  
Magnetic Resonance ◽  
Neuromyelitis Optica ◽  
Demyelinating Diseases ◽  
Proton Nuclear Magnetic Resonance ◽  
Resonance Spectroscopy ◽  
H Nmr ◽  
Nuclear Magnetic

Background:Neuromyelitis optica (NMO) and multiple sclerosis (MS), two inflammatory demyelinating diseases, are characterized by different therapeutic strategies. Currently, the only biological diagnostic tool available to distinguish NMO from MS is the specific serum autoantibody that targets aquaporin 4, but its sensitivity is low.Objective:To assess the diagnostic accuracy of metabolomic biomarker profiles in these two neurological conditions, compared to control patients.Methods:We acquired serum spectra (47 MS, 44 NMO and 42 controls) using proton nuclear magnetic resonance (1H-NMR) spectroscopy. We used multivariate pattern recognition analysis to identify disease-specific metabolic profiles.Results:The1H-NMR spectroscopic analysis evidenced two metabolites, originating probably from astrocytes, scyllo-inositol and acetate, as promising serum biomarkers of MS and NMO, respectively. In 87.8% of MS patients, scyllo-inositol increased 0.15 to 3-fold, compared to controls and in 74.3% of NMO patients, acetate increased 0.4 to 7-fold, compared to controls. Using these two metabolites simultaneously, we can discriminate MS versus NMO patients (sensitivity, 94.3%; specificity, 90.2%).Conclusion:This study demonstrates the potential of1H-NMR spectroscopy of serum as a novel, promising analytical tool to discriminate populations of patients affected by NMO or MS.

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