title: The conformational analysis and photoisomerization of retinochrome analogs with polyenals.
abstract: 3,7-Dimethyl-2,4,6,8,10-dodecapentaenal was synthesized for reconstitution of the retinochrome analog. Its opsin shift was 1000 cm-1 smaller than that of native retinochrome, whose chromophore contains the same number of double bonds. The conformational change from 6-s-trans to 6-s-cis, as figured in a retinal molecule, plays an important role in the formation of the retinochrome analog, based on the estimation of opsin shifts for retinal analogs locked in the 6-s conformation. Thus the conformation of the 6-7 single bond in the native retinochrome was suggested to be 6-s-cis. Analysis of the circular dichroic spectra of retinochrome analogs revealed that the 6-s conformation is independent of the appearance of the beta-band. The stereoselectivity in the photoisomerization of the retinal analogs by a retinochrome template depends on the hydrophobic binding in the region of the beta-ionone ring.
authors.affiliation: Department of Applied Physics and Chemistry, University of Electro-Communications, Tokyo, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kinumi
authors.forename: K
authors.initials: K
authors.lastname: Tsujimoto
authors.forename: M
authors.initials: M
authors.lastname: Ohashi
authors.forename: R
authors.initials: R
authors.lastname: Hara
authors.forename: T
authors.initials: T
authors.lastname: Hara
authors.forename: K
authors.initials: K
authors.lastname: Ozaki
authors.forename: M
authors.initials: M
authors.lastname: Sakai
authors.forename: Y
authors.initials: Y
authors.lastname: Katsuta
authors.forename: A
authors.initials: A
authors.lastname: Wada
authors.forename: M
authors.initials: M
authors.lastname: Ito
mesh_terms: D002942:Circular Dichroism; D008968:Molecular Conformation; D010777:Photochemistry; D012168:Retinal Pigments / Q000737:chemistry*; D012172:Retinaldehyde / Q000031:analogs & derivatives / Q000737:chemistry; D017299:Rod Opsins / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet
chemical_list: D012168:Retinal Pigments; D017299:Rod Opsins; C023421:retinochrome; D012172:Retinaldehyde