A novel approach to correlation spectroscopy (COSY), exclusive correlation spectroscopy (ECOSY), total correlation spectroscopy (TOCSY), incredible natural–abundance double–quantum transfer experiment (INADEQUATE), heteronuclear single–quantum correlation spectroscopy (HSQC), heteronuclear multiple–bond correlation spectroscopy (HMBC), nuclear overhauser effect spectroscopy (NOESY) and rotating frame nuclear overhauser effect spectroscopy (ROESY) comparative study on malignant and benign human cancer cells and tissues under synchrotron radiation

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.

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Revised structure of a delta-aminolevulinic acid derivative

Clinical Chemistry ◽

10.1093/clinchem/39.9.1867 ◽

1993 ◽

Vol 39 (9) ◽

pp. 1867-1871 ◽

Cited By ~ 5

Author(s):

M Kajiwara ◽

K Hara ◽

K Takatori ◽

K Matsumoto

Keyword(s):

Aminolevulinic Acid ◽

Nuclear Overhauser Effect ◽

Correlation Spectroscopy ◽

Molecular Formula ◽

X Ray ◽

Overhauser Effect ◽

13C Nuclear Magnetic Resonance ◽

Relative Arrangement ◽

Effect Difference ◽

Nuclear Overhauser

Abstract The structure of the fluorescent derivative formed in the method of Okayama et al. (Clin Chem 1990; 36:1494-7) for determining delta-aminolevulinic acid (ALA) concentrations was reinvestigated after esterification. The molecular ion peak at m/z 303.1473 corresponded to the molecular formula of C17H21NO4 (calcd 303.1470). The infrared spectrum showed the presence of carbonyl and carboxyl groups. This compound contained two acetyl groups, two methyl groups, and one methoxycarbonylethyl group, as revealed by 1H and 13C nuclear magnetic resonance and 13C-1H shift-correlated spectroscopy. Experiments with correlation spectroscopy via long-range coupling indicated that the main skeleton is 3H-pyrrolizine. The relative arrangement of functional groups was determined by means of nuclear Overhauser effect difference experiments. We were led to the conclusion that the methyl ester of the derivative is 2,6-diacetyl-1,5-dimethyl-7-(2-methoxycarbonylethyl)-3H-pyrrolizine. This structure was unequivocally confirmed by x-ray analysis; therefore, the structure of the derivative itself is 2,6-diacetyl-1,5-dimethyl-7-(2-carboxyethyl)-3H-pyrrolizine.

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Synthesis, NMR Characterization, and Antileukemic Activity of N-Nonanoylpiperazinyl-5α-Androstane-3α,17β-Diol A-Ring Derivatives

Magnetochemistry ◽

10.3390/magnetochemistry7010003 ◽

2020 ◽

Vol 7 (1) ◽

pp. 3

Author(s):

Donald Poirier ◽

Imad Raad ◽

Jenny Roy ◽

René Maltais

Keyword(s):

Multiple Bond ◽

Correlation Spectroscopy ◽

Heteronuclear Multiple Bond Correlation ◽

Steroid Nucleus ◽

New Family ◽

Overhauser Effect ◽

Nmr Characterization ◽

Crucial Information ◽

Heteronuclear Single Quantum Correlation ◽

The Impact

The combination of an androstane-3,17-diol nucleus and a 2β-N-alkylamidopiperazino sidechain is important for the anticancer activity of a new family of steroid derivatives. As the structure-activity relationship studies have so far been limited to the beta orientation of the substituent at position 2 of the steroid nucleus, a series of analogs (compounds 1–4) were synthesized to investigate the impact on biological activity of A-ring substitution. Nuclear magnetic resonance (NMR) analysis, especially using a series of 2D experiments, such as correlation spectroscopy (COSY), homonuclear Overhauser effect spectroscopy (NOESY), heteronuclear single-quantum correlation (HSQC), and heteronuclear multiple-bond correlation (HMBC) provided crucial information that was found essential in confirming the sidechain position and orientation of compounds 1–4. Assessment of their antiproliferative activity on leukemia HL-60 cells confirmed the best efficiency of the 2β-sidechain/3α-OH orientation (compound 1) compared to the other configurations tested (compounds 2–4).

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1H-n.m.r. investigation of naturally occurring and chemically oversulphated dermatan sulphates. Identification of minor monosaccharide residues

Biochemical Journal ◽

10.1042/bj2670625 ◽

1990 ◽

Vol 267 (3) ◽

pp. 625-630 ◽

Cited By ~ 30

Author(s):

V Bossennec ◽

M Petitou ◽

B Perly

Keyword(s):

Glucuronic Acid ◽

Nuclear Overhauser Effect ◽

Double Quantum ◽

Dermatan Sulphate ◽

Proton Proton ◽

Pig Skin ◽

Overhauser Effect ◽

Naturally Occurring ◽

Iduronic Acid ◽

Nuclear Overhauser

The 1H-n.m.r. spectra of various dermatan sulphate preparations present, besides the major signals of the basic disaccharide unit, several other minor signals. We have assigned most of them by n.m.r., using two-dimensional proton-proton double-quantum-correlation and nuclear-Overhauser-effect spectroscopy experiments. This allowed us to identify 2-O-sulphated L-iduronic acid and D-glucuronic acid residues as well as 6-sulphated N-acetylgalactosamine (presumably 4-O-sulphated as well). 2-O-Sulphated iduronic acid was present to similar extents (6-10% of total uronic acids) in pig skin dermatan sulphate and pig intestine dermatan sulphate, whereas glucuronic acid represented 17% of the uronic acid of pig skin dermatan sulphate and was virtually absent (1%) from the other preparation. 6-O-Sulphated N-acetylgalactosamine was present in minor amounts in pig intestine dermatan sulphate only. The influence of sulphation of iduronic acid units on their conformation was assessed by using chemically oversulphated pig intestine dermatan sulphate. Introduction of sulphate groups in this unit in dermatan sulphate tends to shift the conformational equilibrium towards the 1C4 conformer.

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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.

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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.

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Cylindromicin from Arctic-Derived Fungus Tolypocladium sp. SCSIO 40433

Molecules ◽

10.3390/molecules26041080 ◽

2021 ◽

Vol 26 (4) ◽

pp. 1080

Author(s):

Imran Khan ◽

Jing Peng ◽

Zhuangjie Fang ◽

Wei Liu ◽

Wenjun Zhang ◽

...

Keyword(s):

Secondary Metabolites ◽

Nuclear Overhauser Effect ◽

Inhibition Activity ◽

Tyrosinase Inhibition ◽

Bioactive Natural Products ◽

Chemical Structures ◽

Overhauser Effect ◽

Spectroscopic Analyses ◽

Potential Resource ◽

Nuclear Overhauser

The fungus strain SCSIO 40433 was isolated from an Arctic-derived glacier sediment sample and characterized as Tolypocladium cylindrosporum. A new compound, cylindromicin (1), and seven known secondary metabolites (2–8) were isolated from this strain. The chemical structures of these compounds were elucidated by comprehensive spectroscopic analyses. Cylindromicin (1) featured a 3,4-dihydro-2H-pyran skeleton. The absolute configuration of compound 1 was assigned via interpretation of key Nuclear Overhauser Effect Spectroscopy (NOESY) correlations and Electronic Circular Dichroism (ECD) calculation. Cylindromicin (1) exhibited significant tyrosinase inhibition activity. This study highlights Polar fungi as a potential resource for new bioactive natural products.

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