Extrinsic circular dichroic effects in retinoates
Abstract
(–)-1-Phenylethyl retinoate shows a Cotton effect with c.d. bands at 360, 245, and 215 nm, whereas (+)-octan-2-yl retinoate has no such band in the 220–450 nm region. This can be explained either in terms of a dipole–dipole interaction between the phenyl and retinylidene moieties or in terms of the dissymmetric environment of the polyene. The results are pertinent to the origin of c.d. in rhodopsins.