Mechanism for conversion of spirosolane derivative into pregnane
Toshihiro Nohara1, Kahori Okamoto, Sayaka Matsushita
1Faculty of Pharmaceutical Sciences, Sojo University, Kumamoto, Japan. none@ph.sojo-u.ac.jp
Abstract:
Previously, we reported an interesting reaction by which esculeogenin A [(5alpha,22S,23S,25S)-3beta,23,27-trihydroxyspirosolane], a sapogenol of tomato-saponin, esculeoside A, was easily converted into a pregnane derivative, 5alpha-pregn-16-en-3beta-ol-20-one, merely by refluxing with pyridine and water. Its chemical mechanism including air oxidation is here described.
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