FLUORINATED PHENYLRHODOPSIN ANALOGS - BINDING SELECTIVITY, RESTRICTEDROTATION AND F-19-NMR STUDIES

Results from interactions of the 11-cis and 9-cis isomers of eleven fl uorinated phenylretinal analogs, prepared from fluorinated benzaldehyd es, with bovine opsin have been examined. Five of these (2',6'-bis-CF3 , 2',4',6'-tris-CF3, 2'-CF3-6'-F, 2'-CF3-7-methyl and 2'-CF3,6'-F,8-F) formed pigments in moderate to high yields, thus allowing recording o f their F-19-NMR spectra which revealed inhibited conformational equil ibration when protein bound. Possible causes for binding selectivity a nd fluorine chemical shifts are discussed.