Circular dichroism (CD) spectra of the 2, 2′-binaphthyl ester derived from Δ5-sterols showed not bisignate CD but diagnostic CD bands at around 210 and 240nm. These bands might be attributable to an interaction between an olefinic chromophore and a binaphthyl one. Various types of unsaturated sterols were thus derivatized followed by complete hydrogenation, to give saturated sterols. As a result, CD spectra of the binaphthyl ...