An Improved Synthesis Route of Molnupiravir and its Key Impurities

The use of the chromous chloride-ethylenediamine (CrCl2-en) complex to speed dechlorination and minimize side-products has been explored for heptachlor metabolites and degradation products. Five pentachloro heptachlor derivatives are synthesized, and their nuclear magnetic resonance and mass spectra are presented and discussed. Nuclear magnetic resonance data support the anti assignment of H- in the major products from CrCl2-en reduction of cyclodiene pesticides. The use of this reagent for possible development of chemical confirmatory tests for heptachlor metabolites and degradation products is also briefly discussed.

L-Prolyl-L-valine anhydride (I) was obtained from the cultured broth of Streptomyces No. K-73 as a by-product of an antibiotic No. 13-1. The structural elucidation of I were done by the determination of infrared, nuclear magnetic resonance (NMR), 13C-NMR, and mass spectra. Conformation of 2, 5-diketopiperazine group compounds was discussed from the NMR spectra.

Metabonomics is a latest developed system science after genomics and proteomics, which mainly studies changed regularity of metabolites and reveals metabolic nature of organism' vital movement.This article mainly introduces investigative methods of metabonomics such as Nuclear Magnetic Resonance (NMR) and Mass Spectrum(MS).Meanwhile reviews the application and advancement of metabonomics in clinical diagnosis, pharmaprejects, toxicology and other fields, especially emphasizes on application of meta-bonomics in diabetes mellitus, and looks forward to its developing perspective. Key words: Metabonomics; Diabetes mellitus; Nuclear Magnetic Resonance; Mass Spectrum

8, 2'-Anhydro-8-mercapto- 9-β-D-arabinofuranosyladenine (I), 8, 3'-anhydro-8-mercapto-9-β-D-xylofuranosyladenine (II) and 8, 5'-anhydro-8-mercapto-9-β-D-ribofuranosyladenine (III) were deaminated with barium nitrite in acetic acid to give the corresponding S-cycloinosines (IV-VI). These cyclonucleosides had characteristic properties in ultraviolet (UV), nuclear magnetic resonance (NMR), circular dichroism (CD) and mass spectra, which were as expected from those of adenosine cyclonucleosides. Compounds IV-VI were benzoylated on sugar OH groups and subjected to thiolation reaction using phosphorus pentasulfide in pyridine containing water. Deprotection either with sodium methoxide or ammonia in methanol gave 8, 2'-anhydro-6, 8-dimercapto-9-β-D-arabinofuranosylpurine (XVI), 8, 3'-anhydro-6, 8-dimercapto-9-β-D-xylofuranosylpurine (XVII) and 8, 5'-anhydro-6, 8-dimercapto-9-β-D-ribofuranosylpurine (XVIII), respectively. The structure of these cyclonucleosides was confirmed by their characteristic UV, CD, NMR and mass spectra. 6-Mercaptopurine cyclonucleosides were easily oxidized to form disulfides by air oxidation or iodine treatment.

In vitro and in vivo antileishmanial activity of parthenin a sesquiterpene lactone obtained from Parthenium hysterophorous

In vitro incubation of all-trans-retinol (atROL) with kidney homogenate from vitamin A-deficient and retinoic acid-supplemented (VAD-RAS) female rats produces a new retinol metabolite. Reverse-phase (RP) and normal-phase (NP) high-performance liquid chromatography (HPLC) analysis showed that this metabolite coelutes with the unknown all-trans-retinol (atROL) metabolite previously found in the day 10 conceptus and kidneys of vitamin A-deficient rats maintained on all-trans-retinoic acid (VAD-RA) and given 2 microg of [3H]atROL. Normal-phase (NP) HPLC purification of the metabolite collected from a RP HPLC column further separated the radiolabeled material into two components. The two isolated compounds have identical or very similar spectroscopic properties. Their nuclear magnetic resonance (1H NMR) and mass spectra (MS) indicated that they are isomers. Spectroscopic studies of the metabolites and their derivatives showed that they are nine-carbon fragments resulting from an oxidative cleavage of the side chain of atROL. The cleavage occurs at C-9, and the product is then oxidized to a keto group. The primary hydroxy group from atROL is preserved in the metabolite. A sulfide bridge is formed between C-11 and C-14, which interrupts the conjugation. The formation of the new metabolites, possessing a 2,5-dihydrothiophene ring, is catalyzed by an enzyme(s) located in the cytosolic fraction of kidneys. The process represents a new retinol metabolic pathway; however, its biological significance is unknown.

Ethyl 2-cyano 3-(4-dimethylaminophenyl) acrylate crystals were grown by slow cooling method by the condensation reaction of 4-dimethylaminobenzaldehyde and methyl cyanoacetate. The molecular structure of the crystal was confirmed by single crystal X-ray diffraction, 1H Nuclear Magnetic Resonance (1H NMR), 13C Nuclear Magnetic Resonance (13C NMR) and Mass spectrum. The single crystal X-ray diffraction study revealed that the crystal belongs to the triclinic crystal system with space group P. The functional groups of the crystal were confirmed by Fourier transform infrared spectrum. The absorption properties of the crystal were analysed by Ultraviolet–Visible absorption spectrum. The Molar extinction coefficient of the crystal was also calculated using Beer Lamberts law. The emission behaviour of the compound was analysed by Photoluminescence spectrum. Cyclic voltammetry of the compound was analysed through three electrode system at the scan rate of 100 mV/s and HOMO-LUMO of the crystal was calculated by cyclic voltammetry. The thermal behaviour of the crystal was analysed by Thermal gravimetric and differential thermal analysis (TG-DTA). The photo conductivity of the crystal was measured and the result shows that the crystal exhibits positive conductivity.

Written as a quick reference to the many different concepts and ideas encountered in chemistry, Basic Chemical Concepts and Tables presents important subjects in a concise format that makes it a practical resource for any reader. The author covers multiple subjects including general chemistry, inorganic chemistry, organic chemistry, and spectral analysis. Separate chapters offer physical constants and unit measurements commonly encountered and mathematical concepts needed when reviewing or working with basic chemistry concepts. Other features include: Tables that are useful as for the interpretation of ultra-violet (UV), infra-red (IR), nuclear magnetic resonance (NMR) and mass spectroscopy (MS) spectra. Physical constants and unit measurements that are commonly encountered throughout the application of chemistry. Sections devoted to the concept of isomers and polymer structures. Graduate and undergraduate chemistry students, professionals, or instructors looking to refresh their understanding of a chemistry topic will find this ready reference indispensable in their daily work. Written as a quick reference to the many different concepts and ideas encountered in chemistry, Basic Chemical Concepts and Tables presents important subjects in a concise format that makes it a practical resource for any reader. The author covers multiple subjects including general chemistry, inorganic chemistry, organic chemistry, and spectral analysis. Separate chapters offer physical constants and unit measurements commonly encountered and mathematical concepts needed when reviewing or working with basic chemistry concepts. Other features include: Tables that are useful as for the interpretation of ultra-violet (UV), infra-red (IR), nuclear magnetic resonance (NMR) and mass spectroscopy (MS) spectra. Physical constants and unit measurements that are commonly encountered throughout the application of chemistry. Sections devoted to the concept of isomers and polymer structures. Graduate and undergraduate chemistry students, professionals, or instructors looking to refresh their understanding of a chemistry topic will find this ready reference indispensable in their daily work.

A series of new phenyl esters based on a 5,16-pregnadiene-20-one skeleton, namely 3β-benzoyloxy-5,16-pregnadiene-20-ones, which may be good inhibitors of 17α-hydroxylase and 5α-reductase enzyme or useful intermediates for producing steroidal drugs, were synthesized starting from diosgenin. The structures of the steroids were characterized by 1H nuclear magnetic resonance (NMR), 13C NMR, infrared (IR), and mass spectra.

In the present work series of small molecules (5a–5m, 6a–6j) were schematically designed and synthesized using simple chemical procedures. Their structures were confirmed based upon findings from infrared, 1H nuclear magnetic resonance (NMR), 13C NMR, and mass spectra. The derivatives were evaluated for their in vitro malonyl CoA decarboxylase inhibition activity by using fluorimetric assay. Pyrazol-1-yl-1, 3-thaizol-4(5H)-one derivative (5a–5m) showed better activity than pyrazol-1-yl-1-ethanone derivatives (6a–6j). Compounds 5e, 5j, and 6f showed an excellent in vitro malonyl CoA decarboxylase inhibition activity with IC50 value 0.10, 0.27, and 0.26 μM, respectively. These most active compounds 5e, 5j, and 6f were docked into malonyl-CoA decarboxylase (HsMCD, PDB ID: 2YGW) to study ligand–protein interaction.

An automated multi-order phase correction routine for processing ultra-wideline NMR spectra

Objective: The present investigation is designed to synthesize some new isomeric series of quinazoline-4-one/4-thione derivatives, depending upon on the pharmacophoric model of in-vivo anticancer activity by modifying the structures retaining the fundamental structural features for the activity and screened for their antitumor properties. Methods: A new series of 7-chloro-3-[substituted (amino/phenyl amino)]-2-phenyl quinazolin-4 (3H)-one/thione derivatives and 1-(7-chloro-4-oxo/-2-phenylquinazoline-3 (4H-yl)) substituted urea derivatives were synthesized. The reaction scheme proceeds through 7-chloro-2-phenyl-4H-benzo [d] [1, 3] oxazin-4-one which is the intermediate one. The structures of the newly synthesized compounds were characterised from infrared (IR), H 1 nuclear magnetic resonance (NMR) and mass spectra (m/z) and elemental analysis. The in-vivo antitumor activity was evaluated by body weight analysis, mean survival time and percentage increase in life span methods in Swiss albino mice bearing Ehrilich ascites carcinoma (EAC). Result: The physico-chemical and spectroscopic data established the synthesis of quinazoline derivatives with a common pharmacophore. The synthesized compounds were evaluated for their antitumor properties. Among the newly quinazoline derivatives screened, six compounds (IIh, IIi, IIj, IIIh, IIIi, IIIj)) have shown significant antitumor activity. Conclusion: The quinazoline derivatives obtained from the present study indicates that the amino group at 3 rd position and urea/thiourea group in phenyl hydrazine ring at 3 rd position of quinzoline skeleton are essential for antitumor activity. Compounds IIh, IIi, IIj, IIIh, IIIi and IIIj were found to be biologically active which may be useful as potential resource for the discovery of anti-tumor compound having common quinazoline pharmacophore with lesser toxic effects.

This study presents the multivariable analysis of high resolution nuclear magnetic resonance (NMR) spectra in discrete Fourier transform (DFT) domain. Influences of external environment usually cause random shift that jeopardizes the predictive accuracy of NMR spectra to a certain extent. This study, firstly, theoretically proves that the random shift of NMR spectra could be restrained effectively in the DFT domain. Then, simulated and experimental data were employed to verify the restraining ability of the proposed method. Recognition analysis of NMR spectra dataset for the classification of rapeseed oil and regression analyses of NMR spectra dataset for predicting three critical properties of fish oil was considered in the experimental data analyses. Finally, according to the distribution characteristic of DFT coefficients, the compression of NMR spectra in DFT domain was discussed. Compared with original NMR spectra obtained from DFT of free induction decay (FID) and traditional equal interval integral (EII) method which is usually used to restrain random shift of NMR spectra, the proposed method was proved to be more powerful not only in improving the accuracy of the multivariable analysis of NMR spectra, but also in compressing the high dimensionality of NMR spectra.

IntroductionAccuracy of feature annotation and metabolite identification in biological samples is a key element in metabolomics research. However, the annotation process is often hampered by the lack of spectral reference data in experimental conditions, as well as logistical difficulties in the spectral data management and exchange of annotations between laboratories.ObjectivesTo design an open-source infrastructure allowing hosting both nuclear magnetic resonance (NMR) and mass spectra (MS), with an ergonomic Web interface and Web services to support metabolite annotation and laboratory data management.MethodsWe developed the PeakForest infrastructure, an open-source Java tool with automatic programming interfaces that can be deployed locally to organize spectral data for metabolome annotation in laboratories. Standardized operating procedures and formats were included to ensure data quality and interoperability, in line with international recommendations and FAIR principles.ResultsPeakForest is able to capture and store experimental spectral MS and NMR metadata as well as collect and display signal annotations. This modular system provides a structured database with inbuilt tools to curate information, browse and reuse spectral information in data treatment. PeakForest offers data formalization and centralization at the laboratory level, facilitating shared spectral data across laboratories and integration into public databases.ConclusionPeakForest is a comprehensive resource which addresses a technical bottleneck, namely large-scale spectral data annotation and metabolite identification for metabolomics laboratories with multiple instruments. PeakForest databases can be used in conjunction with bespoke data analysis pipelines in the Galaxy environment, offering the opportunity to meet the evolving needs of metabolomics research. Developed and tested by the French metabolomics community, PeakForest is freely-available at https://github.com/peakforest.

Principle component analysis (PCA) was used to extract components from the solid-state nuclear magnetic resonance (NMR) spectra of bacterial cellulose (BC). Polymers such as cellulose have several domain structures, and their structure and dynamics are reflected in the variety of solid-state spectra derived from different parameters. The complexity of the obtained spectra makes the analysis of spectra from relaxation measurements difficult. Multivariate analysis, such as PCA, has been suggested as an option to improve NMR spectral analyses. In this study, we attempted to extract peak components from cross polarization (CP) experiment data from the variable contact time spectra of BC by using PCA. The extracted peaks were annotated according to previous reports, and the existence of crystalline Iα was clearly recognized. The important components of the BC structure (that is, crystalline Iα, amorphous form and mobility) were separated in the PCA-loading plot and CP curve. A multivariate analysis was used to extract components in solid-state nuclear magnetic resonance (NMR) spectra from bacterial cellulose (BC). Polymers such as cellulose have several domain structures, and their structure and dynamics are reflected in the variety of solid-state spectra derived from different parameters. Multivariate analysis, such as principle component analysis (PCA), is suggested as an option to improve analyses of complex NMR spectra from relaxation measurements. In this study we demonstrate the extraction of peak components using PCA from cross polarization experiment data with variable contact time spectra of BC.