It has now been shown that Acetate A
1) previously obtained by isomerizing ilexol acetate is nothing other than urs-13 (18)-en-3β-yl acetate prepared
2) from α-amyrin, furnishing conclusive evidence for its conversion into one of the compounds of the ursane series.
Isoilexol, oxidized with chromium trioxide at room temperature, afforded a ketone named isoilexone, C
30H
48O, m.p. 194-195°, [α]_??_+75.90° (c, 0.527), and oxidized with the same oxidant at 70-80°C, another ketone named isoilexenedione, C
30H
46O
2, m.p. 221-223°, [α]_??_+16.28° (c, 0.307).
Huang-Milon reduction of these ketones afforded one and the same deoxy compound named isoilexene, C
30H
50, m.p. 183-185°, [α]_??_+48.34° (c, 0.290), which might well be assumed to constitute a pair of optical antipodes with olean-13 (18)-ene, C
30H
50, m.p. 184-185°, [α]_??_-48.50° (c, 0.545).
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