Natural occurrence of archaetidic acid and caldarchaetidic acid (di- and tetra-ether analogues of phosphatidic acid) in the archaebacterium Methanohacterium thermautotrophicum

1990 ◽  
Vol 68 (1) ◽  
pp. 91-95 ◽  
Author(s):  
Masateru Nishihara ◽  
Yosuke Koga
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Mass Spectra ◽  
Fast Atom Bombardment ◽  
Ether Lipid ◽  
Natural Occurrence ◽  
Phospholipid Biosynthesis ◽  
Nuclear Magnetic Resonance Spectra ◽  
Minor Phospholipid ◽  
A Minor

A minor phospholipid designated as PL5, assumed to be a precursor of phospholipid biosynthesis, was isolated from Methanohacterium thermautotrophicum. The structures of this lipid and another closely related phospholipid (PL4) were elucidated by infrared spectra, fast atom bombardment mass spectra, 31P-nuclear magnetic resonance spectra, and chemical and enzymatic analyses. These lipids were identified as archaetidic acid (PL5) and caldarchaetidic acid (PL4) (diether and tetraether analogues of phosphatatidic acid, respectively).Key words: archaetidic acid, caldarchaetidic acid, Methanohacterium thermautotrophicum, archaebacterium, ether lipid.

scholarly journals Spectrometric Study of the Nitrile-Ketenimine Tautomerism

2009 ◽  
Vol 2009 ◽  
pp. 1-18 ◽  
Author(s):  
Hebe Saraví Cisneros ◽  
Sergio Laurella ◽  
Danila L. Ruiz ◽  
Agustín Ponzinibbio ◽  
Patricia E. Allegretti ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Mass Spectrum ◽  
Magnetic Resonance ◽  
Mass Spectra ◽  
Spectrometric Study ◽  
Mass Spectral ◽  
Ion Fragmentation ◽  
Nuclear Magnetic Resonance Spectra ◽  
Amination Product

Mass spectrometry is used to evaluate the occurrence of the nitrile-ketenimine tautomerism. Mass spectra of two differently substituted nitriles, ethyl-4,4-dicyano-3-methyl-3-butenoate and diethyl-2-cyano-3-methyl-2-pentenodiate are examined looking for common mass spectral behaviors. Ion fragmentation assignments for specific tautomers allow to predict the presence of the corresponding structures. Additionally, the mass spectrum and nuclear magnetic resonance spectra of ethyl-4,4-dicyano-2,2-diethyl-3-methyl-3-butenoate and that of the corresponding amination product support the occurrence of the ketenimine tautomer in the equilibrium.

The Nematocidal Principles of Tagetes Roots

1963 ◽  
Vol 16 (3) ◽  
pp. 475 ◽  
Author(s):  
DHS Horn ◽  
JA Lamberton
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Mass Spectra ◽  
Nuclear Magnetic Resonance Spectra ◽  
Magnetic Resonance Spectra ◽  
Nuclear Magnetic

The structure assigned to the liquid nematocidal principle of Tagetes roots 5-(3-buten-1-ynyl)-2,2'-bithienyl (II), by Uhlenbroek and Bijloo, has been confirmed by studying the mass spectra and nuclear magnetic resonance spectra of (II) and its hydrogenation products. α-Terthienyl (I) and (II) have also been isolated from fresh roots of T. minuta (T. glandulifera).

Metabolites of Lachnellula fuscosanguinea (Rehm). Part 2. The structure of lachnellulone

1988 ◽  
Vol 66 (3) ◽  
pp. 506-512 ◽  
Author(s):  
William A. Ayer ◽  
J. Daniel Figueroa Villar ◽  
Barbara S. Migaj
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Absolute Configuration ◽  
Mass Spectra ◽  
Antifungal Metabolite ◽  
X Ray ◽  
Crystallographic Study ◽  
Nuclear Magnetic Resonance Spectra ◽  
The Absolute ◽  
Nuclear Magnetic

Lachnellulone, an antifungal metabolite produced by Lachnellula fuscosanguinea (Rehm) Dennis is shown to possess structure 8. The structure was determined by consideration of the ultraviolet, infrared, 1H and 13C nuclear magnetic resonance, and mass spectra of 8 and its derivatives and was confirmed by an X-ray crystallographic study of lachnellulone p-nitrobenzoate. In solution lachnellulone undergoes facile isomerization to isolachnellulone (9a), which explains the observed mutarotation of 8. The 13C nuclear magnetic resonance spectra of lachnellulone and the related lachnelluloic acid (1) are discussed in some detail. The absolute configuration of lachnellulone has not been determined.

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