| Abstrakt: |
The conversion of a lanostane skeleton into a cucurbitane (C‐9β‐Me) has been explored. Several derivatives with an oxirane ring in the appropriate location to induce a methyl migration (while having an adjacent oxygen function as required in the cucurbitacins) have been treated with SnCl4. The reaction took however, a different course and the products have been analysed and identified. During treatment with SnCl4of the epoxy‐lanostane derivative having a diosphenol system in ring A, an acid stable organo‐tin complex was observed to be formed. Base hydrolysis of this complex produced compounds similar to those obtained in the previous examples. |
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