Synthesis of a novel brassinosteroid type with an annelated dioxonane side chain

Abstract

In studies directed towards the synthesis of 25-hydroxybrassinolide 1 we found, that upon reaction of intermediate 7 with trimethylaluminium–n-butyllithium an alkylating fission of the epoxide ring and rearrangement of the tetrahydropyranyl unit takes place to afford after deprotection the new dioxonane-annelated brassinosteroid 9.

References

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