Synthesis of Retinals Fluorinated at Odd-Numbered Side-Chain Positions and of the Corresponding Fluorobacteriorhodopsins

Autor:	Alvarez R, Susana López, de Lera Ar, Andrés Francesch
Rok vydání:	1997
Předmět:	chemistry.chemical_compound chemistry Stereochemistry mental disorders Organic Chemistry Wittig reaction Side chain Retinal
Zdroj:	Scopus-Elsevier
ISSN:	1520-6904 0022-3263
DOI:	10.1021/jo961355x
Popis:	Conventional Horner-Wadsworth-Emmons and Wittig condensations were used to fluorinate the odd-numbered positions of the retinal side chain past C(7). The stereochemically labile cis-fluororetinals were easily converted into the most stable trans-fluororetinals, which were incubated with bacterio-opsin. Contrary to expectations, the fluorinated retinals provided artificial pigments with near normal absorption properties, showing that any electrostatic interactions between the fluorine atoms and protein groups were insufficient to prevent normal binding. The new artificial pigments had smaller opsin shifts than did native bacteriorhodopsin, which is interpreted as due either to greater electrostatic interaction between the protonated imine and its counterion, or to local interactions between the fluorine substituents and nearby polar protein groups.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::0c03a29c2518671df3eb387cf9896bb9 https://doi.org/10.1021/jo961355x Zobrazit plný text záznamu