Lupane-3β,28-diol, lupan-3β-ol, and friedelan-3β-ol were treated with m-chloroperbenzoic acid (mCPBA) in refluxing chloroform to afford corresponding lactones in one step, while lupane-3β,28-diyl diacetate, lupan-3β-yl acetate, and friedelan-3β-yl acetate to give hydroxylated or keto derivatives. Similar reaction of dendropanoxide with mCPBA yielded 6β-, 7β-, 21α-, and 22β-hydroxylated compounds.
Dry ozonation of friedelane afforded 18β,19β-epoxyfriedelane, 19-oxofriedelane, 16-oxofriedelane, 21-oxofriedelane, friedelin, and a new compound, 15-oxofriedelane. Friedelin, on dry ozonation, gave 3,16-dioxofriedelane, 3,19-dioxofriedelane, and new compounds, 18β,19β-epoxyfriedelan-3-one and 3,15-dioxofriedelane. It was shown that the oxidation occurred at D and E rings regioselectively in the dry ozonation.
木屑烷的干臭氧化得到 18β,19β-环氧木屑烷、19-氧代木屑烷、16-氧代木屑烷、21-氧代木屑烷、木屑烷和新化合物 15-氧代木屑烷。 Friedelin 通过干臭氧化,得到 3,16-二氧弗里德兰、3,19-二氧弗里德兰和新化合物 18β,19β-环氧弗里德兰-3-酮和 3,15-二氧弗里德兰。结果表明,在干臭氧氧化中,氧化区域选择性地发生在 D 环和 E 环处。