Litoralimycins A and B, New Cytotoxic Thiopeptides from Streptomonospora sp. M2

Streptomonospora sp. M2 has been isolated from a soil sample collected at the Wadden Sea beach in our ongoing program aimed at the isolation of rare Actinobacteria, ultimately targeting the discovery of new antibiotics. Because crude extracts derived from cultures of this strain showed inhibitory activity against the indicator organism Bacillus subtilis, it was selected for further analysis. HPLC–MS analysis of its culture broth revealed the presence of lipophilic metabolites. The two major metabolites of those were isolated by preparative reversed-phase HPLC and preparative TLC. Their planar structures were elucidated using high-resolution electrospray ionization mass spectrometry (HRESIMS), 1D and 2D NMR data as new thiopeptide antibiotics and named litoralimycin A (1) and B (2). Although rotating frame nuclear Overhauser effect spectroscopy (ROESY) data established a Z configuration of the Δ21,26 double bond, the stereochemistry of C-5 and C-15 were assigned as S by Marfey’s method after ozonolysis. The biological activity spectrum of 1 and 2 is highly uncommon for thiopeptide antibiotics, since they showed only insignificant antibacterial activity, but 1 showed strong cytotoxic effects.

Download Full-text

A New Thiopeptide Antibiotic, Micrococcin P3, from a Marine-Derived Strain of the Bacterium Bacillus stratosphericus

Molecules ◽

10.3390/molecules25194383 ◽

2020 ◽

Vol 25 (19) ◽

pp. 4383

Author(s):

Weihong Wang ◽

Kyu-Hyung Park ◽

Jusung Lee ◽

Eunseok Oh ◽

Chanyoon Park ◽

...

Keyword(s):

Mass Spectrometry ◽

High Resolution Mass Spectrometry ◽

2D Nmr ◽

Antibacterial Activities ◽

Culture Broth ◽

Gram Positive ◽

Gram Positive Bacteria ◽

New Antibiotics ◽

Thiopeptide Antibiotics ◽

Bacterium Bacillus

A new thiopeptide (micrococcin P3, 1) and a known one (micrococcin P1, 2) were isolated from the culture broth of a marine-derived strain of Bacillus stratosphericus. The structures of both compounds were elucidated using spectroscopic methods, including extensive 1D and 2D NMR analysis, high resolution mass spectrometry (HRMS), and tandem mass spectrometry. Both compounds exhibited potent antibacterial activities against Gram-positive strains with minimum inhibitory concentration (MIC) values of 0.05−0.8 μg/mL and did not show cytotoxicity in the MTT assay up to a concentration of 10 μM. This study adds a new promising member, micrococcin P3, to the family of thiopeptide antibiotics, which shows potential for the development of new antibiotics targeting Gram-positive bacteria.

Download Full-text

Benderamide A, a Cyclic Depsipeptide from a Singapore Collection of Marine Cyanobacterium cf. Lyngbya sp.

Marine Drugs ◽

10.3390/md16110409 ◽

2018 ◽

Vol 16 (11) ◽

pp. 409 ◽

Cited By ~ 3

Author(s):

Chi Ding ◽

Ji Ong ◽

Hui Goh ◽

Cynthia Coffill ◽

Lik Tan

Keyword(s):

Breast Cancer Cells ◽

Nuclear Overhauser Effect ◽

2D Nmr ◽

Marine Cyanobacterium ◽

One Dimensional ◽

Mechanistic Pathway ◽

Overhauser Effect ◽

Cyclic Depsipeptide ◽

Nuclear Overhauser ◽

Related Compounds

Benderamide A (1), a (S)-2,2-dimethyl-3-hydroxy-7-octynoic acid (S-Dhoya)-containing cyclic depsipeptide that belongs to the kulolide superfamily, was isolated from a Singapore collection of cf. Lyngbya sp. marine cyanobacterium using a bioassay-guided approach. While the planar structure of 1 was elucidated using a combination of 1D and 2D NMR experiments and MS analysis, the absolute configuration was subsequently achieved using the results obtained from Marfey’s analysis, comparative analysis of nuclear overhauser effect spectroscopy (NOESY) with the known compound 3, and one dimensional-nuclear overhauser effect (1D-NOE). Although 1 did not display antiproliferative activity against MCF7 breast cancer cells, the presence of an Ala instead of Gly suggests a possible mechanistic pathway to explain the consequential decrease in cytotoxicity compared to the closely related 2. In addition, results obtained from an LC–MS/MS-based molecular networking algorithm revealed two other closely related compounds encouraging further identification and isolation from the same marine cyanobacterium extract.

Download Full-text

Microstructural study of cetyltrimethylammonium bromide / 1-butanol / salt / water system — SANS and 2D-NOESY analysis

Canadian Journal of Chemistry ◽

10.1139/v11-155 ◽

2012 ◽

Vol 90 (3) ◽

pp. 314-320 ◽

Cited By ~ 4

Author(s):

K. Kuperkar ◽

A. Patriati ◽

E.G.R. Putra ◽

K. Singh ◽

D.G. Marangoni ◽

...

Keyword(s):

Cetyltrimethylammonium Bromide ◽

Nuclear Overhauser Effect ◽

Salt Water ◽

Total Concentration ◽

Water System ◽

2D Nmr ◽

Spectral Shift ◽

Micellar Aggregates ◽

2D Noesy ◽

Nuclear Overhauser

Interaction of 1-butanol (BuOH) with a cationic surfactant, cetyltrimethylammonium bromide (CTAB) aggregate, in water and salt solution has been studied by viscometry, small-angle neutron scattering (SANS), and 2D-NMR techniques. The experimental results are interpreted in terms of a possible micellar growth occurring in the presence of added alcohol and salt. It was observed that the addition of BuOH strongly influences the viscosity of the CTAB/salt micellar system, reaching a peak viscosity at about 0.5% w/v of BuOH over a range of salt concentrations. Scattering measurements support the idea of a structural transformation by the observation of a spectral shift (broadening) as the total concentration of surfactant varies, indicating a decrease in the intermicellar distance and narrow size distribution. The chemical shift from 1H NMR measurements gave complementary data on the solubilization of BuOH in CTAB micelles, whereas the expected locus (site) of the additive added to the surfactant including the dynamics of the molecules in micellar aggregates were successfully correlated by significant and positive cross peaks obtained from two-dimensional nuclear Overhauser effect spectroscopy (2D-NOESY).

Download Full-text

The isolation and structural elucidation of a new iridoid glycoside from Cymbaria dahurica L.

Zeitschrift für Naturforschung B ◽

10.1515/znb-2017-0205 ◽

2018 ◽

Vol 73 (6) ◽

pp. 377-379 ◽

Cited By ~ 1

Author(s):

Cui-Lan Bai ◽

Qing-Hu Wang ◽

Yan-Hua Xu ◽

Jun-Sheng Han ◽

Yin-Ping Bao

Keyword(s):

Quantum Coherence ◽

Nuclear Overhauser Effect ◽

Multiple Bond ◽

2D Nmr ◽

Iridoid Glycoside ◽

Correlation Spectroscopy ◽

Etoac Extract ◽

Overhauser Effect ◽

Nuclear Overhauser ◽

C Nmr

AbstractA new iridoid glycoside, namely, cymdahoside A (1), together with two known ones, 2 and 3, were isolated from the EtOAc extract of Cymbaria dahurica. The structure elucidation of 1 was carried out by one-dimensional (1D) NMR (1H and 13C NMR) and 2D NMR (correlation spectroscopy, heteronuclear single-quantum coherence, heteronuclear multiple-bond correlation and nuclear Overhauser effect spectroscopy) spectral analyses.

Download Full-text

Comparison of Regular, Pure Shift, and Fast 2D NMR Experiments for Determination of the Geographical Origin of Walnuts

Metabolites ◽

10.3390/metabo11010039 ◽

2021 ◽

Vol 11 (1) ◽

pp. 39

Author(s):

Stephanie Watermann ◽

Caroline Schmitt ◽

Tobias Schneider ◽

Thomas Hackl

Keyword(s):

Statistical Analysis ◽

1H Nmr ◽

Nmr Spectra ◽

Geographical Origin ◽

Nuclear Overhauser Effect ◽

Juglans Regia ◽

2D Nmr ◽

Support Vector ◽

Nuclear Overhauser ◽

The One

1H NMR spectroscopy, in combination with chemometric methods, was used to analyze the methanol/acetonitrile (1:1) extract of walnut (Juglans Regia L.) regarding the geographical origin of 128 authentic samples from different countries (France, Germany, China) and harvest years (2016–2019). Due to the large number of different metabolites within the acetonitrile/methanol extract, the one-dimensional (1D) 1H NOESY (nuclear Overhauser effect spectroscopy) spectra suffer from strongly overlapping signals. The identification of specific metabolites and statistical analysis are complicated. The use of pure shift 1H NMR spectra such as PSYCHE (pure shift yielded by chirp excitation) or two-dimensional ASAP-HSQC (acceleration by sharing adjacent polarization-heteronuclear single quantum correlation) spectra for multivariate analysis to determine the geographical origin of foods may be a promising method. Different types of NMR spectra (1D 1H NOESY, PSYCHE, and ASAP-HSQC) were acquired for each of the 128 walnut samples and the results of the statistical analysis were compared. A support vector machine classifier was applied for differentiation of samples from Germany/China, France/Germany, and France/China. The models obtained by conduction of a repeated nested cross-validation showed accuracies from 58.9% (±1.3%) to 95.9% (±0.8%). The potential of the 1H-13C HSQC as a 2D NMR experiment for metabolomics studies was shown.

Download Full-text

New Antifungal Metabolites from the Mariana Trench Sediment-Associated Actinomycete Streptomyces sp. SY1965

Marine Drugs ◽

10.3390/md18080385 ◽

2020 ◽

Vol 18 (8) ◽

pp. 385 ◽

Cited By ~ 1

Author(s):

Wenwen Yi ◽

Le Qin ◽

Xiao-Yuan Lian ◽

Zhizhen Zhang

Keyword(s):

High Performance ◽

Nuclear Overhauser Effect ◽

Ionization Mass ◽

Mariana Trench ◽

Streptomyces Sp ◽

Antifungal Metabolites ◽

Ionization Mass Spectroscopy ◽

Noesy Experiment ◽

Nuclear Overhauser ◽

New Compounds

New streptothiazolidine A (1), streptodiketopiperazines A (2) and B (3), and (S)-1-(3-ethylphenyl)-1,2-ethanediol (4), together with eight known compounds (5–12), were isolated from the Mariana Trench sediment-associated actinomycete Streptomyces sp. SY1965. The racemic mixtures of (±)-streptodiketopiperazine (2 and 3) and (±)-1-(3-ethylphenyl)-1,2-ethanediol (4 and 5) were separated on a chiral high-performance liquid chromatography (HPLC) column. Structures of the new compounds were elucidated by their high-resolution electrospray ionization mass spectroscopy (HRESIMS) data and extensive nuclear magnetic resonance (NMR) spectroscopic analyses. Streptothiazolidine A is a novel salicylamide analogue with a unique thiazolidine-contained side chain and its absolute configuration was established by a combination of nuclear Overhauser effect spectroscopy (NOESY) experiment, electronic circular dichroism (ECD) and 13C NMR calculations. New streptothiazolidine A (1) and streptodiketopiperazines A (2) and B (3) showed antifungal activity against Candida albicans with MIC values of 47, 42, and 42 g/mL, respectively.

Download Full-text

Sesquiterpenes from the Saudi Red Sea: Litophyton arboreum with their cytotoxic and antimicrobial activities

Zeitschrift für Naturforschung C ◽

10.1515/znc-2017-0037 ◽

2018 ◽

Vol 73 (1-2) ◽

pp. 9-14 ◽

Cited By ~ 3

Author(s):

Lamia T. Abou El-Kassem ◽

Usama W. Hawas ◽

Samy K. El-Desouky ◽

Radwan Al-Farawati

Keyword(s):

Red Sea ◽

Quantum Coherence ◽

Nuclear Overhauser Effect ◽

Multiple Bond ◽

Cancer Cell Line ◽

2D Nmr ◽

Antimicrobial Activities ◽

Correlation Spectroscopy ◽

Coherence Spectroscopy ◽

Nuclear Overhauser

AbstractA new pseudoguaiane-type sesquiterpene named litopharbol (1) was isolated from the methanolic extract of the Red Sea soft coralLitophyton arboreum, along with known sesquiterpenoids alismol (2), alismorientol B (3), teuhetenone A (4), and calamusin I (5); steroid, 24-methyl-cholesta-5,24(28)-diene-3β-ol (6), alkyl glyceryl ether, chimyl alcohol (7); sphingolipid, erythro-N-dodecanoyl-docosasphinga-(4E,8E)-dienine (8); and nitrogenous bases, thymine (9) and thymidine (10). The structures were determined on the basis of nuclear magnetic resonance (NMR) spectroscopic (1D and 2D NMR data including heteronuclear single quantum coherence spectroscopy, heteronuclear multiple-bond correlation spectroscopy, and nuclear Overhauser effect spectroscopy) and mass spectrometric analyses. Compounds1–5were explored for antimicrobial activity and cancer cell line sensitivity tests. Compound1exhibited antibacterial activity againstBacillus cereuswith a minimum inhibition concentration of 1.8 μg/mL, whereas compound3showed significant potent cytotoxic effect against MCF-7 (breast cancer cells) with IC504.32 μM.

Download Full-text

Synthesis and 2D NMR characterization of Ni(II), Pd(II), and Cu(II) complexes with H2cdsalen (methyl-2{N-[2-(2′-hydroxyphenyl)methylidenenitrilo]ethyl}amino-1-cyclopentenedithiocarboxylate)

Canadian Journal of Chemistry ◽

10.1139/v11-153 ◽

2012 ◽

Vol 90 (3) ◽

pp. 237-242

Author(s):

T.J. Morales-Juárez ◽

M.C. Sánchez-López ◽

R.M. Gómez-Espinosa ◽

I. García-Orozco ◽

D. Corona-Becerril

Keyword(s):

Nuclear Overhauser Effect ◽

2D Nmr ◽

Conformational Studies ◽

Overhauser Effect ◽

Nmr Characterization ◽

Nuclear Overhauser ◽

2D Roesy

In this study we report on the preparation of Ni(II), Pd(II), Co(II), and Cu(II) complexes with H2cdsalen (methyl-2{N-[2-(2′-hydroxyphenyl)methylidenenitrilo]ethyl}amino-1-cyclopentenedithiocarboxylate)salicylaldehyde. The products were characterized using 1D NMR (1H and 13C) and 2D NMR (COSY, NOESY, and ROESY) techniques. The conformational studies of the complexes with Ni and Pd in solution have been performed with help of the nuclear Overhauser effect (NOE) and 2D ROESY experiments.

Download Full-text

Chemical constituents and anti Helicobacter pylori effect of ethyl acetate fraction from Sanchezia nobilis Hook.F

International Journal of Research in Pharmaceutical Sciences ◽

10.26452/ijrps.v11i3.2760 ◽

2020 ◽

Vol 11 (3) ◽

pp. 4715-4721

Author(s):

Xuan Bui Thi ◽

Loi Vu Duc ◽

Duong Le Hong ◽

Ngoc Tran Minh

Keyword(s):

Helicobacter Pylori ◽

Ethyl Acetate ◽

Chemical Constituents ◽

Ethyl Acetate Fraction ◽

2D Nmr ◽

Inhibitory Effect ◽

Reversed Phase ◽

Ionization Mass ◽

Concentration Method ◽

First Time

The leaves of Sanchezia Nobilis Hook. F grown in Vietnam are extracted with ethanol then distilled for ethanol retrievement under low pressure. The ethanol concentrate was shaken with n-hexane, then stirred with ethyl acetate and concentrated fractions were obtained. From the high ethyl acetate fraction, four compounds were isolated by normal phase and reversed-phase column chromatography. Their structures were determined by spectral analysis, including 1D and 2D NMR techniques (1H, 13C, DEPT, COZY, HSQC, HMBC and NOESY), High Resolution - Electrochewmical Ionization - Mass Spectroscopy (HR-ESI-MS), and identified by comparing with the recorded data. Among the isolated compounds, compound 2 (13-O-acetylfawcettimine) was first time isolated from nature; and mixture 1 (Fawcettidin), 3 (Apigenin) and 4 (Kaempferol) were first time isolated from the Sanchezia genus. The high ethyl acetate fraction of Sanchezia Nobilis Hook. F leaves were then evaluated for the anti-Helicobacter pylori (anti-HP) effect by determining the minimum inhibitory concentration method (MIC), which showed a good inhibitory, dose−dependent effect on Helicobacter pylori. The ethyl acetate fraction at 1/8 dilution showed a complete inhibitory effect on Helicobacter pylori for as long as 24 hours. At 1/128 dilution, the fraction only showed good results on inhibition after 24 hours.

Download Full-text

1H NMR studies of [N-MeAib1, Tyr(Me)4]ANGII and [N-MeAib1, Tyr(Me)4, Ile8]ANGII in dimethylsulfoxide by nuclear Overhauser effect (NOE) enhancement spectroscopy: cis-trans Isomerism of the His-Pro bond

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19901106 ◽

1990 ◽

Vol 55 (4) ◽

pp. 1106-1111 ◽

Cited By ~ 1

Author(s):

John Matsoukas ◽

Paul Cordopatis ◽

Raghav Yamdagni ◽

Graham J. Moore

Keyword(s):

1H Nmr ◽

Nuclear Overhauser Effect ◽

Nmr Studies ◽

Restricted Rotation ◽

Overhauser Effect ◽

Major Isomer ◽

Conformational Properties ◽

Nuclear Overhauser

The conformational properties of the Sarmesin analogues [N-MeAib1, Tyr(Me)4]ANGII and [N-MeAib1, Tyr(Me)4, Ile8]ANGII in hexadeutero-dimethysulfoxide were investigated by Nuclear Overhauser Effect (NOE) Enhancement Studies. Cis-trans isomers (ratio 1 : 6) due to restricted rotation of the His-Pro bond were observed. Interresidue interactions between the His Cα proton and the two Pro Cδ protons revealed that the major isomer was the trans.

Download Full-text