Novel approach to determining the absolute configurations at the C3-positions of various types of sterols based on an induced circular dichroism

作者：Fujiwara Toshio; Taniguchi Yuka; Katsumoto Yukiteru; Tanaka Takeyuki; Ozeki Minoru; Iwasaki Hiroki; Node Manabu; Yamashita Masayuki^*; Hosoi Shinzo

来源：Steroids, 2012, 77(12): 1198-1204.

DOI：10.1016/j.steroids.2012.07.006

• Induced circular dichroism
• Absolute configuration
• Binaphthyl esters
• Exciton chirality
• Bisignate curves

Circular dichroism (CD) spectra of the 2,2%26apos;-binaphthyl ester derived from Delta(5)-sterols showed not bisignate CD but diagnostic CD bands at around 210 and 240 nm. 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 derivatives of the saturated sterols showed bisignate curves centered at 240 nm (3S(beta): positive chirality; 3R(alpha): negative one). This suggested a straightforward and practical method for discriminating the absolute stereogenic center at the C-3 positions of sterols based on an induced CD. This finding should contribute significantly to the analysis of metabolites of various types of sterols.

• 出版日期2012-10