ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The reaction of all-trans-retinal and 5-(2,6,6-trimethylcyclohexeyl)-3-methyl-2,4-pentadienal with amino acids, amino esters and their salts was studied. The structure of the polyenic imines and iminium salts thus prepared was elucidated with the aid of 1H-and 13C-NMR spectroscopy. The condensation results in an equilibrium between the imine and its zwitterionic form as shown by variable-temperature 13C-NM measurements. Addition of an inorganic salt (LiClO4) favours the zwitterionic form. Comparison of the 13C chemical shifts of these species with those obtained from the protonation of the corresponding imino-ester gave the percentage of the two forms. The species prepared from the amino acids constitute model compounds, and rhodopsin and bacteriorhodopsin are believed to exhibit similar behaviour.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19840670512
