scholarly journals Tropane alkaloids from a Brazilian bark traded as "Catuaba"

2003 ◽  
Vol 71 (2) ◽  
pp. 113-119
Author(s):  
Sabine Glasl ◽  
Armin Presser ◽  
Ingrid Werner ◽  
Ernst Haslinger ◽  
Johann Jurenitsch

Dichloromethane extracts of a Brazilian bark assigned as Anemopaegma mirandum contained four tropane alkaloids. MS-, UV-, IR-, 1H NMR-data and specific optical rotation allowed the identification of catuabin C and its 7-exo-hydroxy-20-methyl-derivative. As no alkaloids are described for Anemopaegma these results indicate heterogeneity for the investigated drug and require a further review.

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiaoyan Pang ◽  
Weihao Chen ◽  
Xin Wang ◽  
Xuefeng Zhou ◽  
Bin Yang ◽  
...  

Three new tetramic acid derivatives (1–3) and a new polyketide (4) along with eight known compounds (5–12) were isolated from cultures of the deep-sea-derived fungus Penicillium sp. SCSIO06868. Four new structures were elucidated by analysis of one-dimensional/two-dimensional nuclear magnetic resonance (NMR) data and high-resolution electrospray ionization mass spectrometry. Their absolute configurations were established by X-ray crystallography analysis and comparison of the experimental and reported electronic circular dichroism (ECD) values or specific optical rotation. Compound 3 exhibited potent, selective inhibitory activities against Staphylococcus aureus and methicillin-resistant S. aureus with minimum inhibitory concentration values of both 2.5 μg/ml. Also, compound 3 showed weak antiviral activity against severe acute respiratory syndrome coronavirus 2 main protease, which was responsible for the coronavirus disease 2019 pandemic.


Planta Medica ◽  
2016 ◽  
Vol 81 (S 01) ◽  
pp. S1-S381
Author(s):  
SF Ullrich ◽  
A Rothauer ◽  
O Kayser

2008 ◽  
Vol 59 (10) ◽  
Author(s):  
Paul Ionut Dron ◽  
Neculai Doru Miron ◽  
Gheorghe Surpateanu

The paper presents the synthesis of cyclo (bis-paraquat p-phenylene p-phenylene-carbonyl) tetrakis (hexafluorophosphate), named �CETOBOX�, and the closely related structural determinations. This compound exists in three tautomeric forms. These forms were evidentiated by NMR-data (1H-NMR, TOCSY, COSY, NOESY), UV-Vis spectra coupled with pH measurements and by synthesis. As the �CETOBOX� gives �in situ� only the corresponding monoylide, the synthesis of a new fluorescent indolizine cyclophane has been performed by a 3+2 cycloaddition. All structures of the new compounds presented herein have been established by NMR spectroscopy. Also, theoretical methods (MM3, AM1, AM1-COSMO and B88LYPDFT) have been used to determine the most stable conformer structures.


Marine Drugs ◽  
2021 ◽  
Vol 19 (2) ◽  
pp. 65
Author(s):  
Byeoung-Kyu Choi ◽  
Duk-Yeon Cho ◽  
Dong-Kug Choi ◽  
Phan Thi Hoai Trinh ◽  
Hee Jae Shin

Two new phomaligols, deketo-phomaligol A (1) and phomaligol E (2), together with six known compounds (3–8) were isolated from the culture broth of the marine-derived fungus Aspergillus flocculosus. Compound 1 was first isolated as a phomaligol derivative possessing a five-membered ring. The structures and absolute configurations of the new phomaligols were determined by detailed analyses of mass spectrometry (MS), nuclear magnetic resonance (NMR) data, optical rotation values and electronic circular dichroism (ECD). In addition, the absolute configurations of the known compounds 3 and 4 were confirmed by chemical oxidation and comparison of optical rotation values. Isolated compounds at a concentration of 100 μM were screened for inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-induced BV-2 microglial cells. Among the compounds, 4 showed moderate anti-neuroinflammatory effects with an IC50 value of 56.6 μM by suppressing the production of pro-inflammatory mediators in activated microglial cells without cytotoxicity.


2012 ◽  
Vol 518-523 ◽  
pp. 3989-3992 ◽  
Author(s):  
Yang Zhang ◽  
Xiao Hua Tu ◽  
Cheng Ping Miao ◽  
Jian Yi Wu

A novel CIL of N-butyl-N-methyl imidazolium-D-(-)-tartrate has been designed and synthesized by neutralization reaction. Its structure was characterized by 1H-NMR and 13C-NMR spectra, the optical rotation was characterized by polarimeter with the value of-15.0º, and the purity was characterized by ion chromatography with the value of 98.4%.


2021 ◽  
pp. 1-9
Author(s):  
Chuanqi Duan ◽  
Weiyuan Liu ◽  
Liang Chen ◽  
Jing Pan ◽  
Yubin Liu ◽  
...  
Keyword(s):  
1H Nmr ◽  

1976 ◽  
Vol 143 (2) ◽  
pp. 422-436 ◽  
Author(s):  
M E Pereira ◽  
E A Kabat

The purified lectins from Lotus tetragonolobus and Dolichos biflorus were coupled to Sepharose 2B to make insoluble adsorbents for purification and fractionation of blood group A and H active glycoproteins. With both adsorbents, hog gastric mucin A + H blood substance (HGM), purified by phenol-ethanol precipitation, yielded fractions showing only A, only H, or AH activities. The AH fraction was obtained when the adsorbent column was overloaded with HGM and its A and H specificities seem to be carried on the same molecules since they were not separable by chromatography on either column. However A and H specificities of blood group substance from the stomach of a presumably heterozygous individual hog were both on the same molecules as they too could not be fractionated on either column. Analytical properties of the isolated fractions were generally similar to those of the unfractionated material, the purfied A substances had a higher galactosamine/fucose ratio than did the H substances. Although the original A + H showed very little specific optical rotation, the separated A and H substances rotated positively and negatively, respectively. The lectin-Sepharose adsorbents have also proven useful in isolating A or H substances directly from the crude commercial hog gastric mucin. Blood group A2 substance from a human ovarian cyst yielded two fractions on the Lotus-Sepharose column; the effluent did not interact with the Lotus lectin but precipitated the Ulex and Dolichos lectins and anti-A, and appears to contain type 1 H determinants. The other fraction reacted with Lotus and Ulex lectin as well as with Dolichos and anti-A.


2020 ◽  
Author(s):  
Alexander Howarth ◽  
Kristaps Ermanis ◽  
Jonathan Goodman

<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>


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