Shionanes

The conversion of shionone into dihydrobaccharis oxide (80) has been reported.59 3/3,4/3-Epoxyshionane (81), on treatment with boron trifluoride etherate, afforded (80) and bacchar-12-en-3j8-ol (82). The high-resolution mass spectral fragmentation patterns of a number of shionane and friedelane derivatives have been examined.60... 

The second group contains oleananes (644), ursanes (649), friede-lanes (647), danunaranes (636), shionanes (639) and others. They are derived from squalene (627) in the chair-chair-chair-boat conformation... 

Taraxeranes, Multiflorane, Glutinanes, Friedelanes, Isoursane, Phyllanthane, Bauerane, and Shionanes... 

When the dehydration of diol monoacetate (395) was carried out in deuterioacetic acid, all rearrangement products were formed free of deuterium, indicating that no elimination-reprotonation takes place under the reaction conditions (487). The backbone rearrangement of cholesterol (396) in the presence of hydrofluoric acid is combined with expansion of the D ring and 1,5-hydrogen transfer from the side-chain to give the shionane-like product (397) (488). 

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