Conversion of spirostane and solanidane into pregnane (1)introduction of oxygen function into C-23.
A spirosolane derivative possessing a hydroxyl group at C-23, esculeogenin A, a sapogenol of tomato saponin, was found to be easily converted into the corresponding pregnane derivative by refluxing with aqueous pyridine. Therefore, introduction of a hydroxyl group into the C-23 of diosgenin (as representative of spirostane derivatives) and solasodine (as representative of spirosolane derivatives) was attempted by the reaction of NaNO(2)-BF(3) · Et(2)O. In diosgenin, the objective compound was obtained by the reaction in AcOH. However, in solasodine, we obtained a 23-nitroso derivative by the reaction in AcOH and 23,24-bisnorcholanic acid 22-16 lactone, or vespertilin, in AcOH and CHCl(3).
Faculty of Medical and Pharmaceutical Scieces, Sojo University, 4-22-1 Ikeda, Kumamoto 860-0082, Japan.
Nodoka
N
Nakata
Asami
A
Tokudome
Hiroyuki
H
Yanai
Toshihiro
T
Nohara
D018551:Solanum lycopersicum / Q000737:chemistry; D010100:Oxygen / Q000737:chemistry*; D011278:Pregnanes / Q000138:chemical synthesis / Q000737:chemistry*; D012502:Sapogenins / Q000737:chemistry; D012991:Solanaceous Alkaloids / Q000737:chemistry*; D013150:Spirostans / Q000737:chemistry*
D011278:Pregnanes; D012502:Sapogenins; D012991:Solanaceous Alkaloids; D013150:Spirostans; C505181:isoesculeogenin A; C012037:solasodine; D010100:Oxygen