Previously (1962), the authors have separated a new 4-methyl sterol, named “gramisterol”, from the unsaponifiables of wheat germ oil by column chromatography. Its structure was presumed to be 4α-methyl-Δ
7, 24 (28) -ergostadien-3β-ol. Later (1964 and 1965), Schreiber
et al. reported the presence of 24-methylene lophenol in potato leaf and sugar cane.
The 24-methylene lophenol might be considered to be identical with gramisterol, because the former has the structure of 4α-methyl-Δ
7, 24 (28) -ergostadien-3β-ol, that was given for the latter.
Since the 24-methylene lophenol in those plants has not been isolated in a pure state, authors attempted in this study to isolate gramisterol (24-methylene lophenol) in a high state of purity from the unsaponifiables of wheat germ oil by preparative thin-layer chromatography, and confirmed by TLC, IR, NMR and MS that the previously supposed structure for gramisterol was correct.
Purified gramisterol showed mp 162163°C, [α]
D+2.9°, and its acetate, mp 132134°C, [α]
D+24.3°.
Formerly separated gramisterol was found to contain citrostadienol as impurity.
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