NMR spectra and stereochemistry ofN-acetyl andN-benzoyl derivatives of solasodine
作者:Asmita V. Patel、Gerald Blunden、Trevor A. Crabb
DOI:10.1002/mrc.1260290809
日期:1991.8
N-Acetylation of solasodine gives only one rotameric N-acetyl derivative compared with N-acetyl-3-methylpiperidine, which exists in solution as two equally populated rotamers. The 1H and 13C NMR spectra (CDCl3) of O,N-diacetyl- and O-acetyl-N-benzoylsolasodine indicate significant deviations from F-ring chair geometry. Opening of the F ring of these derivatives in CDCl3 solution at 25°C, to give the corresponding furosta-5,20(22)-diene derivatives, was ascertained by NMR spectroscopy.
与 N-乙酰基-3-甲基哌啶相比,索拉索定的 N-乙酰化反应只产生一种 N-乙酰基转子衍生物,而 N-乙酰基-3-甲基哌啶在溶液中存在两个同样多的转子。O,N-二乙酰基和 O-乙酰基-N-苯甲酰基拉索定的 1H 和 13C NMR 光谱(CDCl3)表明,它们明显偏离了 F 环椅几何形状。通过核磁共振光谱,可以确定这些衍生物的 F 环在 25°C 的 CDCl3 溶液中打开,生成相应的呋喃甾-5,20(22)-二烯衍生物。