Stereoselective reactions. XII Synthesis of antitumor-active steganacin analogs, picrosteganol and epipicrosteganol, by selective isomerization.
作者:KIYOSHI TOMIOKA、TSUNEO ISHIGURO、YOICHI IITAKA、KENJI KOGA
DOI:10.1248/cpb.34.1501
日期:——
New steganacin analogs with definite absolute configurations, (-)-picro- and (-)-epipicrosteganol, were synthesized by isomerization of (-)-steganol and (-)-episteganol, respectively, at the α-position to the lactone carbonyl. The structure of (-)-epipicrosteganol was confirmed by X-ray crystallographic analysis. Selective epimerization at the C-4 benzylic position was observed upon acidic treatment of (-)-steganacin, giving (-)-episteganacin.