ChemInform Abstract: ALKALI ISOMERIZATION OF METHYL 9,12,15-OCTADECATRIENOATE GEOMETRICAL ISOMERS

1984 ◽  
Vol 15 (37) ◽  
Author(s):  
S. KORITALA
Keyword(s):  
Alkali Isomerization ◽  
Geometrical Isomers

1H, 13C and 15N NMR Spectra of Coupling Products of Benzenediazonium Salts with Aliphatic Nitro Compounds and Study of Their E/Z Isomerism

1996 ◽  
Vol 61 (4) ◽  
pp. 589-596 ◽  
Author(s):  
Antonín Lyčka
Keyword(s):  
Dimethyl Sulfoxide ◽  
Nmr Spectra ◽  
Chemical Shifts ◽  
Nitro Compounds ◽  
Coupling Constants ◽  
15N Nmr ◽  
Geometrical Isomers ◽  
Sodium Salts ◽  
Aliphatic Nitro Compounds ◽  
Tautomeric Forms

The 1H, 13C and 15N NMR spectra have been measured of coupling products of benzenediazonium salts with nitromethane, nitroethane, 1-nitropropane, 2-nitroethanol and of their sodium salts, and the chemical shifts have been unambiguously assigned. The coupling products have been found to exist only in their hydrazone tautomeric forms. Stereospecific behaviour of the coupling constants 2J(15N,1H) and 2J(15N,13C) in the 15N isotopomers and NOESY have been used to differentiate between the E and Z geometrical isomers. The above-mentioned compounds exist as Z isomers in deuteriochloroform and predominantly (>95%) as E isomers in dimethyl sulfoxide, while the sodium salts are present only as E isomers in dimethyl sulfoxide.

Biological activity of the two geometrical isomers of methomyl on maize mitochondria

1983 ◽  
Vol 22 (11) ◽  
pp. 2431-2435 ◽  
Author(s):  
G. Aranda ◽  
C. Gauvrit ◽  
M. Cesario ◽  
J. Guilhem ◽  
C. Pascard ◽  
...  
Keyword(s):  
Biological Activity ◽  
Geometrical Isomers

A simple HPLC method for the comprehensive analysis of cis/trans (Z/E) geometrical isomers of carotenoids for nutritional studies

2013 ◽  
Vol 138 (2-3) ◽  
pp. 1341-1350 ◽  
Author(s):  
Antonio J. Melendez-Martinez ◽  
Carla M. Stinco ◽  
Chun Liu ◽  
Xiang-Dong Wang
Keyword(s):  
Hplc Method ◽  
Comprehensive Analysis ◽  
Geometrical Isomers ◽  
Nutritional Studies

scholarly journals Kinetic study of the photochemical changes of (ZZ)-bilirubin IX α bound to human serum albumin. Demonstration of (EZ)-bilirubin IX α as an intermediate in photochemical changes from (ZZ)-bilirubin IX α to (EZ)-cyclobilirubin IX α

1985 ◽  
Vol 226 (1) ◽  
pp. 251-258 ◽  
Author(s):  
S Itoh ◽  
S Onishi
Keyword(s):  
Human Serum Albumin ◽  
Serum Albumin ◽  
Kinetic Study ◽  
Human Serum ◽  
Photochemical Reaction ◽  
Relative Rate ◽  
Significant Preference ◽  
Geometrical Isomers ◽  
Relative Rate Constants

The present study was performed to elucidate why the photochemical reaction of (ZZ)-bilirubin bound to human serum albumin is singularly selective, and only one of the two (EZ)- and (ZE)-bilirubins, the (ZE)-isomer, is produced. In a kinetic study of the photochemical reaction in vitro, the sum of the relative rate constants of photochemical transformation of (EZ)-bilirubin into both (EZ)-cyclobilirubin and (ZZ)-bilirubin, with a significant preference for the former, was proved to be considerably larger than that of the transformation of (ZZ)-bilirubin into (EZ)-bilirubin. Therefore only one of the geometrical isomers, namely (ZE)-bilirubin, is apparently formed. It was concluded that (EZ)-bilirubin photochemically undergoes (EZ)-cyclization, i.e. structural photoisomerization, while bound to its high-affinity site on human serum albumin, and is an intermediate in the transformation of (ZZ)-bilirubin into (EZ)-cyclobilirubin.

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