scholarly journals DP4-AI automated NMR data analysis: straight from spectrometer to structure

2020 ◽  
Vol 11 (17) ◽  
pp. 4351-4359 ◽  
Author(s):  
Alexander Howarth ◽  
Kristaps Ermanis ◽  
Jonathan M. Goodman
Keyword(s):  
Data Analysis ◽  
Structure Elucidation ◽  
Organic Molecule ◽  
Automatic Processing ◽  
Molecule Structure ◽  
H Nmr ◽  
Nmr Data ◽  
Robust System

A robust system for automatic processing and assignment of raw 13C and 1H NMR data DP4-AI has been developed and integrated into our computational organic molecule structure elucidation workflow.

Inhibited rotation of amide group around C N bond of nicotinamide in different solvents by 1 H NMR data

2017 ◽  
Vol 231 ◽  
pp. 238-241 ◽  
Author(s):  
G.A. Gamov ◽  
V.V. Aleksandriiskii ◽  
V.A. Sharnin
Keyword(s):  
Amide Group ◽  
H Nmr ◽  
Nmr Data

scholarly journals DP4-AI Automated NMR Data Analysis: Straight from Spectrometer to Structure

2020 ◽  
Author(s):  
Alexander Howarth ◽  
Kristaps Ermanis ◽  
Jonathan Goodman
Keyword(s):  
1H Nmr ◽  
Open Source Software ◽  
Processing Speed ◽  
Structure Elucidation ◽  
Structural Information ◽  
Fold Increase ◽  
Structural Uncertainty ◽  
Large Sets ◽  
Nmr Data ◽  
Objective Model

<div> <p>A robust system for automatic processing and assignment of raw 13C and 1H NMR data DP4-AI has been developed and integrated into our computational organic molecule structure elucidation workflow. Starting from a molecular structure with undefined stereochemistry or other structural uncertainty, this system allows for completely automated structure elucidation. Methods for NMR peak picking using objective model selection and algorithms for matching the calculated 13C and 1H NMR shifts to peaks in noisy experimental NMR data were developed. DP4-AI achieved a 60-fold increase in processing speed, and near-elimination of the need for scientist time, when rigorously evaluated used a challenging test set of molecules. DP4-AI represents a leap forward in NMR structure elucidation and a step-change in the functionality of DP4. It enables high-throughput analyses of databases and large sets of molecules, which were previously impossible, and paves the way for the discovery of new structural information through machine learning. This new functionality has been coupled with an intuitive GUI and is available as open-source software at https://github.com/KristapsE/DP4-AI.</p> </div> <br>

scholarly journals Chemical constituents of Chaenomeles sinensis twigs and their biological activity

2020 ◽  
Vol 16 ◽  
pp. 3078-3085
Author(s):  
Joon Min Cha ◽  
Dong Hyun Kim ◽  
Lalita Subedi ◽  
Zahra Khan ◽  
Sang Un Choi ◽  
...  
Keyword(s):  
Biological Activity ◽  
Data Analysis ◽  
Cell Lines ◽  
Chemical Structure ◽  
Biological Effects ◽  
Chemical Constituents ◽  
2D Nmr ◽  
Nmr Data ◽  
Chaenomeles Sinensis ◽  
Modified Mosher’S Method

A new megastigmane-type norsesquiterpenoid glycoside, chaemeloside (1), was isolated from the twigs of Chaenomeles sinensis together with 11 known phytochemicals through chromatographic methods. The chemical structure of the new isolate 1 was determined by conventional 1D and 2D NMR data analysis, ECD experiment, hydrolysis followed by a modified Mosher’s method, and LC–MS analysis. The characterized compounds’ biological effects including cytotoxicity against cancer cell lines, antineuroinflammatory activity, and potential neurotrophic effect were evaluated.

scholarly journals STUDY OF CONFORMATIONAL PREFERENCES OF ERYTHRO-CAROLIGNAN E ASSESSED BY THE COUPLING BETWEEN H7'-H8' IN DIFFERENT NMR SOLVENTS

2016 ◽  
Vol 11 (1) ◽  
pp. 1
Author(s):  
Rudiyansyah Rudiyansyah ◽  
Ajuk Sapar ◽  
Masriani Masriani
Keyword(s):  
Ethanol Extract ◽  
Coupling Constant ◽  
Relative Configuration ◽  
H Nmr ◽  
Nmr Data ◽  
Conformational Preferences ◽  
Wood Bark

<p><em>Erythro</em>-carolignan E (<strong>1</strong>) has been obtained from the ethanol extract of the wood bark of <em>Durio affinis</em> Becc. This research was conducted in order to prove that conformational preferences of compound <strong>1</strong> were solvent dependent. On the basis of <sup>1</sup>H-NMR data, the relative configuration of compound <strong>1</strong> was characterized by a coupling constant (<sup>3</sup><em>J</em><sub>HH</sub>) value of 3.3 Hz at H-7' in CDCl<sub>3</sub>. The coupling constant (<sup>3</sup><em>J</em><sub>HH</sub>) values of H-7' in compound <strong>1</strong> has changed to 4.1 Hz and 5.3 Hz in pyridine-<em>d</em><sub>5</sub> and acetonitrile-<em>d</em><sub>3</sub> respectively. As a result, the conformation of compound <strong>1</strong> at C7'-C8' has changed in different NMR solvents.  In conclusion, structure of<em>erythro</em>-carolignan E that contains a dihydroxy group at C7'-C8' is able to change in different NMR solvent.</p>

scholarly journals Structure-oriented methods for protein NMR data analysis

2010 ◽  
Vol 56 (4) ◽  
pp. 311-328 ◽  
Author(s):  
Guillermo A. Bermejo ◽  
Miguel Llinás
Keyword(s):  
Data Analysis ◽  
Protein Nmr ◽  
Nmr Data

scholarly journals Synthesis of Some Novel Fused Imidazo [2, 1-b] [1, 3] Thiazole and Imidazo [2, 1-b] Thiazolo [5, 4-d] Isoxazole Derivatives

2012 ◽  
Vol 9 (3) ◽  
pp. 1518-1525 ◽  
Author(s):  
Hamid Reza Jaberi ◽  
Hadi Noorizadeh
Keyword(s):  
Acetic Acid ◽  
Sodium Acetate ◽  
Carbon Disulphide ◽  
Thiazole Derivatives ◽  
H Nmr ◽  
Nmr Data ◽  
Elemental Analyses ◽  
New Compounds ◽  
Isoxazole Derivatives ◽  
C Nmr

In this work we describe the synthesis of some novel fused imidazo [2, 1-b] [1, 3] thiazole derivatives. The reaction of 1, 2-diaminoethane 1 with carbon disulphide in H2O/ETOH as solvent furnishes 4, 5-dihydro-1H-imidazol-2-thiol 2 under reflux condition. the reaction of 4,5-dihydro-1H-imidazol-2-thiol on treatment with ethylchloro acetate and aromatic aldehyde in presence of anhydrous sodium acetate and acetic acid as solvent to give (Z)-2-(arylidene)-5,6-dihydroimidazo [2,1-b] [1,3] thiazol-3(2H)-one 3a-j. Compounds 3a-j was condensed with hydroxylamine to give 3-(aryl)-2, 3, 6, 7-tetrahydroimidazo [2, 1-b] [1,3] thiazolo [5, 4-d] isoxazole 4a-j. The structures of the new compounds were established by elemental analyses, IR,1H NMR and13C NMR data.

scholarly journals Caffeoyl-β-d-glucopyranoside and 1,3-dihydroxy-2-tetracosanoylamino-4-(E)-nonadecene isolated from Ranunculus muricatus exhibit antioxidant activity

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Farooq Azam ◽  
Bashir Ahmad Chaudhry ◽  
Hira Ijaz ◽  
Muhammad Imran Qadir
Keyword(s):  
Antioxidant Activity ◽  
Structure Elucidation ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Scavenging Activity ◽  
Dpph Radical ◽  
Compound A ◽  
Spectral Techniques ◽  
H Nmr ◽  
Aerial Parts

Abstract This study evaluates the antioxidant activity of Ranunculus muricatus and isolation and structure elucidation of the active constituents. The aerial parts of the plants were shade dried at room temperature and powdered and extracted with methanol. The free radical scavenging activity was evaluated by 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay. The percentage scavenging activity was determined based on the percentage of DPPH radical scavenged. Column chromatography was used in order to isolate the active compounds. Spectral techniques UV, IR, 1H NMR, 13CNMR and HREI-MS were used for the structure elucidation of the isolated compounds. Two isolated compounds, A (caffeoyl-β-d-glucopyranoside) and B (1,3-dihydroxy-2-tetracosanoylamino-4-(E)-nonadecene), exibited a significant antioxidant activity as showed by DPPH radical scavenging method. Percentage inhibition for compound A (at 0.5 mM) was 82.67 ± 0.19 with IC50 of 93.25 ± 0.12 (μM), and for compound B (at 0.5 mM) was 69.23 ± 0.19 with IC50 of 183.34 ± 0.13 (μM). Quercetin was used as standard control. It was conclued from the present study that caffeoyl-β-d-glucopyranoside and 1,3-dihydroxy-2-tetracosanoylamino-4-(E)-nonadecene isolated from methanol extract of aerial parts of Ranunculus muricatus posses antioxidant activity.

Sign in / Sign up

Export Citation Format

Share Document